Rozprawy doktorskie na temat „Alcohol use”

Alcohol use (AU) and alcohol use disorder (AUD) are leading causes of morbidity, premature death, and economic burden. They are also associated with high levels of disability and many other negative outcomes. Twin and family studies have consistently shown that AU and AUD are complex traits influenced by both genetic and environmental factors. Although much has been learned about the genetic and environmental etiology of AU and AUD, significant gaps remain. These include the need for a more comprehensive understanding of the roles of risk and protective factors, and the nature of developmental trajectories underpinning the progression from AU to AUD. The aims of this dissertation are: (1) to examine the roles of resilience and personality disorders in the etiology of AU and AUD; (2) to investigate the nature of longitudinal changes in genetic and environmental risk factors responsible for individual differences in AU; and (3) to determine the moderating roles of key environmental risk factors on the impact of aggregate molecular, or polygenic, risk for AU during adolescence. Using both biometrical behavioral genetic and molecular genetic methodologies, five key findings were observed: (1) Resilience is strongly associated with a reduction in risk for AUD, and this relationship appears to be the result of overlapping genetic and shared environmental influences; (2) Borderline and antisocial personality disorders are the strongest and most stable personality pathology predictors of the phenotypic and genotypic liability to AU and AUD across time; (3) Genetic influences on the development of AUD from early adulthood to mid-adulthood are dynamic, whereby two sets of genetic risk factors contribute to AUD risk; (4) The specific genetic influences on AU follow an unfolding pattern of growth over time, whereas unique environmental risk factors are consistent with an accumulation of environmental impacts and risks across time; and (5) High peer group deviance and low parental monitoring are associated with increased AU, while early parental monitoring moderates the polygenic risk for AU at age 20. The implications of these results with regard to prevention and intervention efforts are discussed.

Many studies have explored the relationship of one's alcohol use both to family environment and to the drinking behavior of the parents. However, most of these studies have used clinical samples. The participants in this study were from a non-clinical, college undergraduate sample (N = 206). The sample included 69% females and 31% males who were primarily Caucasian.A causal path model was used to assess the relationships between familial alcohol use, the perceptions of family environment, propensity for substance use, and actual alcohol use. Participants completed the Michigan Alcoholism Screening Test (MAST) for themselves, their parents, and one sibling. Family environment measures completed by participants included: the Children of Alcoholics Screening Test (CAST) to measure the "experience" of family alcohol use; the Family of Origin Scale (FOS) as a measure of the family affectional environment; and the Family Adaptability and Cohesion Scales (FACES Ill) as a measure of family structural and relational factors. The MacAndrew Scale (MAC) was completed to assess the propensity for substance use.A path analysis of the proposed model indicated that family alcohol use did not exert a significant direct effect on propensity for or actual use of alcohol, nor did it exert any significant effect on the family affectional environment. Each of these is a rather surprising result and contrary to results of previous studies. However, family alcohol use significantly affected the "experience" of living in such a family environment, especially when alcohol use became more problematic. Family alcohol use, mediated by this "experience," had significant effects on family structural components of leadership and control, as measured by FACES III. The "experience" of family alcohol use was significantly and negatively related to the affectional environment of the family. The indirect effects of this "experience" were significant only through the control component of family structure and direct effects this "experience" were significant only for actual use of alcohol. Propensity for use and actual use were also significantly related as was expected.Nearly 50% of the sample indicated a propensity for use (MAC > 24), actual problematic use of alcohol (MAST > 5), or both, when using the standard cutoff scores of these instruments. It appears that further analysis of family influences on these behaviors, especially those behaviors that create difficulties in life, is warranted. Treatment approaches have typically maintained that improved family affective and relational environments are primary treatment goals. That the affectional environment of the family was not significantly affected by familial use of alcohol was another unexpected outcome and also warrants further study.
Department of Counseling Psychology and Guidance Services

Background. We examined the association between parental alcohol use disorders and patterns of alcohol consumption and DSM-IV alcohol use disorders in their offspring in a community-based sample of young adults. Methods. Data are based on baseline and 4-year follow-up data of 2427 respondents aged 14–24 at baseline. Alcohol use and disorders in respondents were assessed using the Munich-Composite-International-Diagnostic-Interview with DSM-IV algorithms. Diagnostic information about parents was collected by family history information from the respondents, and by direct interview with one parent (cohort aged 14 to 17 years only). Results. Although the association between maternal and paternal alcohol use disorders and non-problematical drinking in offspring was minimal, there was a strong effect for the transition to hazardous use and for alcohol abuse and dependence; the effect of parental concordance for transition into hazardous use was particularly striking. Maternal history was associated with a higher probability of progression from occasional to regular use, whereas paternal history was associated with progression from regular to hazardous use. Parental alcoholism increased the risk for first onset of hazardous use and alcohol dependence between the ages of 14–17, and for an earlier onset of the alcohol outcomes in offspring. The impact of parental alcohol use disorders was comparable for male and female offspring. Conclusions. Parental alcoholism predicts escalation of alcohol use, development of alcohol use disorders and onset of alcohol outcomes in offspring.

Background. We examined the association between parental alcohol use disorders and patterns of alcohol consumption and DSM-IV alcohol use disorders in their offspring in a community-based sample of young adults. Methods. Data are based on baseline and 4-year follow-up data of 2427 respondents aged 14–24 at baseline. Alcohol use and disorders in respondents were assessed using the Munich-Composite-International-Diagnostic-Interview with DSM-IV algorithms. Diagnostic information about parents was collected by family history information from the respondents, and by direct interview with one parent (cohort aged 14 to 17 years only). Results. Although the association between maternal and paternal alcohol use disorders and non-problematical drinking in offspring was minimal, there was a strong effect for the transition to hazardous use and for alcohol abuse and dependence; the effect of parental concordance for transition into hazardous use was particularly striking. Maternal history was associated with a higher probability of progression from occasional to regular use, whereas paternal history was associated with progression from regular to hazardous use. Parental alcoholism increased the risk for first onset of hazardous use and alcohol dependence between the ages of 14–17, and for an earlier onset of the alcohol outcomes in offspring. The impact of parental alcohol use disorders was comparable for male and female offspring. Conclusions. Parental alcoholism predicts escalation of alcohol use, development of alcohol use disorders and onset of alcohol outcomes in offspring.

Els enzims presenten una sèrie d’avantatges catalítiques respecte als catalitzadors químics emprats en síntesis química clàssica: especificitat, selectivitat i la possibilitat de treballar en condicions suaus de temperatura i pressió. No obstant, també presenten una sèrie de limitacions com són la baixa estabilitat i les baixes productivitats. En el present treball es combinen dues tècniques per tractar d’optimitzar les reaccions d’interès seleccionades: la immobilització i l’enginyeria de reacció. Les reaccions objectiu d’aquest treball són reaccions d’oxidoreducció centrades en la biosíntesis de molècules, de mitjà i alt valor afegit, d’alt interès industrial. En la primera part de la tesis s’ha utilitzat una alcohol deshidrogenasa (ADH99) per a la oxidació de l’alcohol chlorolactol a chlorolactona i una NAD(P)H oxidasa (NOX) com a sistema de regeneració del cofactor. La chlorolactona és un precursor per a la síntesis d’estatines les quals són fàrmacs utilitzats per a la reducció del LDL-colesterol ja que inhibeixen l’enzim encarregat de la seva biosíntesis. Ambdós enzims van ser immobilitzats eficientment en diferents suports, dels quals es van seleccionar els tres que van mostrar major activitat retinguda. Seguidament es va estudiar l’estabilitat dels derivats immobilitzats en condicions de reacció i es va determinar la càrrega enzimàtica màxim per a cada enzim. Es va descartar l’ús de la NOX immobilitzada ja que no es va millorar l’estabilitat amb cap suport. Posteriorment es van optimitzar les condicions de reacció amb un disseny experimental (DoE) amb l’ADH99 soluble però utilitzant la quantitat màxima d’ADH99 que es pot afegir a la reacció quan es fa servir el l’ADH99 immobilitzada en epoxy-agarosa-UAB M2. Finalment es va estudiar la capacitat de reutilització del derivat immobilitzat, on es va poder millorar 1.5 vegades tant el producte obtingut com el rendiment del biocatalitzador. No obstant, la millor configuració va resultar ser la utilització dels dos enzims en forma soluble. La segona part d’aquesta tesis es va centrar en la reacció d’oxidació de l’alcohol vainillínic a vanil·lina biocatalitzada per l’eugenol oxidasa (EUGO). La vanil·lina és la molècula que dona les propietats organolèptiques a la vainilla, el segon aromatitzant més car del món. La síntesi de vanil·lina via biotecnològica és d’un gran interès industrial ja que pot etiquetar-se com a natural. L’EUGO va ser immobilitzada eficientment en diferents suports dels que es van seleccionar els tres que van retenir més activitat i se’n van estudiar els mateixos paràmetres de l’apartat anterior. En aquest cas els tres derivats immobilitzats van ser utilitzats per a realitzar la reacció de síntesi, amb l’objectiu de seleccionar el més estable operacionalment. Tots els derivats van permetre ser reutilitzats 5 vegades conservant una elevada conversió en l’últim cicle. L’epoxy-agarosa-UAB M2 va ser el suport que millor estabilitat va mostrar. Els bons resultats obtinguts en el segon apartat d’aquest treball van permetre aprofundir en aquesta reacció. Pel que, en el tercer apartat, es va realitzar una optimització de les condicions de reacció des del punt de vista de millorar les mètriques del procés i també amb l’objectiu de fer el procés més sostenible ambientalment. A l’hora d’escollir les noves condicions de reacció es van tenir en compte l’activitat de la EUGO i la seva estabilitat. Ambdues condicions van ser testades en la reacció objectiu amb l’EUGO soluble i immobilitzada. En les noves condicions es va poder millorar la productivitat volumètrica 5.7 i 6.6 vegades respectivament, en comparació a les condicions prèvies. Finalment, en el reciclatge de l’enzim immobilitzat es van poder realitzar 5 cicles de reacció en les primeres condicions i 18 cicles de reacció en les noves condicions on es va poder millorar el rendiment del biocatalitzador 3.9 i 12.4 vegades respectivament.
Las enzimas presentan una serie de ventajas catalíticas respecto a los catalizadores químicos empleados en síntesis química clásica: especificidad, selectividad y la posibilidad de trabajar en condiciones suaves de temperatura y presión. No obstante, también presentan una serie de limitaciones como son la baja estabilidad y las bajas productividades. En el presente trabajo se combinan dos técnicas para tratar de optimizar las reacciones de interés seleccionadas: la inmovilización y la ingeniería de reacción. Las reacciones objetivo de este trabajo son reacciones de oxidoreducción centradas en la biosíntesis de moléculas, de medio y alto valor añadido, de alto interés industrial. En la primera parte de la tesis se ha utilizado una alcohol deshidrogenasa (ADH99) para la oxidación del alcohol chlorolactol a chlorolactona y una NAD(P)H oxidasa (NOX) como sistema de regeneración del cofactor. La chlorolactona es un precursor para la síntesis de estatinas las cuales son fármacos utilizados para la reducción del LDL-colesterol puesto que inhiben la enzima encargada de su biosíntesis. Ambas enzimas fueron inmovilizados eficientemente en diferentes soportes, de los cuales se seleccionaron los tres que mostraron mayor actividad retenida. Seguidamente se estudió la estabilidad de los derivados inmovilizados en condiciones de reacción y se determinó la carga enzimática máximo para cada enzima. Se descartó el uso de la NOX inmovilizada puesto que no se mejoró la estabilidad con ningún apoyo. Posteriormente se optimizaron las condiciones de reacción con un diseño experimental (DoE) con la ADH99 soluble pero utilizando la cantidad máxima de ADH99 que se puede añadir a la reacción cuando se usa la ADH99 inmovilizada en epoxy-agarosa-UAB M2. Finalmente se estudió la capacidad de reutilización del derivado inmovilizado, donde se pudo mejorar 1.5 veces tanto el producto obtenido como el rendimiento del biocatalizador. No obstante, la mejor configuración resultó ser la utilización de las dos enzimas en forma soluble. La segunda parte de esta tesis se centró en la reacción de oxidación del alcohol vanillínico a vanillina biocatalizada por la eugenol oxidasa (EUGO). La vanillina es la molécula que da las propiedades organolépticas a la vainilla, el segundo aromatizante más caro del mundo. La síntesis de vainillina vía biotecnológica es de un gran interés industrial puesto que puede etiquetarse como natural. La EUGO fue inmovilizada eficientemente en diferentes soportes de los que se seleccionaron los tres que retuvieron más actividad y se estudiaron los mismos parámetros que en el apartado anterior. En este caso los tres derivados inmovilizados fueron utilizados para realizar la reacción de síntesis, con el objetivo de seleccionar el más estable operacionalmente. Todos los derivados permitieron ser reutilizados 5 veces conservando una elevada conversión en el último ciclo. La epoxy-agarosa-UAB M2 fue el soporte que mejor estabilidad mostró. Los buenos resultados obtenidos en el segundo apartado de este trabajo permitieron profundizar en esta reacción. Por lo que, en el tercer apartado, se realizó una optimización de las condiciones de reacción desde el punto de vista de mejorar las métricas del proceso y también con el objetivo de hacer el proceso más sostenible ambientalmente. A la hora de escoger las nuevas condiciones de reacción se tuvieron en cuenta la actividad de la EUGO y su estabilidad. Ambas condiciones fueron testadas en la reacción diana con lo EUGO soluble e inmovilizada. En las nuevas condiciones se pudo mejorar la productividad volumétrica 5.7 y 6.6 veces respectivamente, en comparación a las condiciones previas. Finalmente, en el reciclaje de la enzima inmovilizada se pudieron realizar 5 ciclos de reacción en las primeras condiciones y 18 ciclos de reacción en las nuevas condiciones donde se pudo mejorar el rendimiento del biocatalitzador 3.9 y 12.4 veces respectivamente.
Enzymes have some catalytic advantages over chemical catalysts used in classical chemical synthesis: specificity, selectivity and the possibility to work under mild conditions of temperature and pressure. However, they also have some limitations such as low stability and low productivity. This work combines two techniques aiming to optimise the target reactions: immobilisation and reaction engineering. The target reactions of this work are redox reactions focused on the biosynthesis of molecules, of medium-high value, of industrial interest. In the first part of the thesis, an alcohol dehydrogenase (ADH99) was used, with an NAD(P)H oxidase (NOX) as a cofactor regeneration system, to oxidise a chlorolactol to chlorolactone. Chlorolactone is a precursor for the synthesis of statins which are drugs used to lower LDL-cholesterol by inhibiting the enzyme responsible for its biosynthesis. Both enzymes were efficiently immobilised on different supports, selecting the three that showed the highest retained activity. The stability of the immobilised derivatives under reaction conditions was studied and the maximum enzyme load for each enzyme also was determined. The use of immobilised NOX was discarded because no stability improvements were achieved with any support. The reaction conditions were optimised by design of experiments (DoE), using soluble ADH99 added at maximum loading onto an epoxy-agarose support. Finally, the reusability of the immobilised enzyme was studied, where both the total product obtained and the biocatalyst yield could be improved 1.5-fold. However, the best configuration resulted from the use of the two enzymes in soluble form. The second part of this thesis was focused on the oxidation reaction of vanillyl alcohol to vanillin catalysed by eugenol oxidase (EUGO). Vanillin is the molecule that gives vanilla its organoleptic properties. Vanillin biotechnological synthesis is of high interest industrially because it is the second most expensive flavouring in the world and the product can be labelled as natural. Similar to the previous section, EUGO was efficiently immobilised onto different supports, selecting the three that retained most activity. These supports were used to study the stability of the immobilised enzyme and the maximum EUGO load that can be immobilised. In this case, the three immobilised derivatives were used to perform the target reaction, in order to select the most stable operationally. All immobilised derivatives could be reused 5 times maintaining a high conversion in the last cycle. Epoxy-agarose-UAB M2 was the support that showed the best stability, improving the biocatalyst yield 3-fold. The encouraging results obtained in the second section of this work allowed us to deepen the study of this reaction. Therefore, in the third section, an optimisation of the reaction conditions was carried out to improve the process metrics and also aiming to make the process more environmentally sustainable. The EUGO activity and its stability were taken into account to choose the reaction conditions. Both conditions, maximum activity and maximum stability, were tested in the target reaction with soluble and immobilised EUGO. Using the new conditions, it was possible to improve the volumetric productivity 5.7 and 6.6-fold respectively, compared to the previous conditions. Finally, the reusability of the immobilised EUGO allowed us to perform 5 reaction cycles and 18 reaction cycles, with unoptimised and optimised reaction conditions respectively. This resulted in an improvement of the biocatalyst yield of 3.9 and 12.4-fold, respectively, compared to reactions with soluble enzyme under the same conditions.
Universitat Autònoma de Barcelona. Programa de Doctorat en Biotecnologia

Background: Many western observational studies suggest moderate alcohol use is associated with better health including lower risk of cardiovascular diseases, diabetes and cognitive decline. However, the apparent benefit is susceptible to confounding by healthier attributes in moderate users. Randomized controlled trials of moderate alcohol use are infeasible. To assess the validity of these association for causal inference, I examined these associations in a setting (Southern China) with a different social patterning of alcohol use from more commonly studied western populations and using a Mendelian randomization design. Objectives: This thesis utilized two large Southern Chinese cohorts, the Guangzhou Biobank Cohort Study (GBCS) (n=30,499) and the Elderly Health Centre (EHC) Cohort (n=64,353) to examine sex-specific association of moderate alcohol use with cognitive function using observational designs. I also examined systematic differences between alcohol users and the credibility of alcohol-metabolizing genes as instruments for Mendelian randomization in GBCS. Mendelian randomization was used to examine the effect of alcohol use on cognitive function and cardiovascular risk factors and morbidity among men in GBCS. Methods: I used multivariable linear regression to examine the adjusted association of alcohol use categories (never, occasional, social weekly (EHC only), moderate, heavy and former) with cognitive function, measured by delayed 10-word recall test (phases 1-3 of GBCS), Mini-Mental State Examination (phase 3 of GBCS) and Abbreviated Mental Test (EHC), stratified by sex and age. I used multinomial logistic regression to examine the sex-specific systematic difference by alcohol category in GBCS. I used multivariable linear regression to examine the genetic association of ALDH2 with different cardiovascular risk factors and morbidities, cognitive outcomes and liver enzymes and to assess if alcohol phenotypes mediated any apparent genetic association in men. I used 2 stage least squares (2SLS) regression to examine the association of alcohol units (10g ethanol/day) with cognitive function and cardiovascular risk factors (blood pressure, lipids and fasting glucose) and morbidities (self reported cardiovascular disease and ischemic heart disease) in men in GBCS. Results: Occasional alcohol use, rather than moderate alcohol use, was consistently associated with higher cognitive function in both studies. Systematic differences among alcohol users were present. Occasional alcohol users had better health attributes while moderate users had slightly poorer attributes compared to never users. Aldehyde dehydrogenase 2 (ALDH2) was a credible instrument for Mendelian randomization. From Mendelian randomization, low to moderate alcohol use was not associated with cognitive function in men. However, it was positively associated with HDL cholesterol and diastolic blood pressure but not with fasting glucose or cardiovascular morbidity in men. Conclusions: Moderate alcohol use was not associated with cognitive function, suggesting that previous positive studies could be confounded by better health attributes in moderate users. The lack of association of alcohol use with cardiovascular morbidity despite raising HDL cholesterol is consistent with non-observational studies showing the non-causal role of HDL cholesterol in cardiovascular disease. These may suggest the apparent cardioprotection of alcohol is confounded although it remains possible that cardioprotection is population-specific via pathways other than HDL cholesterol, which require further investigations.
published_or_final_version
Community Medicine
Doctoral
Doctor of Philosophy

Most institutions of higher education have recognized the detrimental impact of high-risk alcohol use on college students? success and it has been strongly recommended that prevention practitioners incorporate faculty members in prevention efforts in order to reduce college student alcohol use. Despite the large body of literature that has established faculty members are influential in college student success, the impact and influence faculty members have on college student alcohol use has not been thoroughly researched. The purpose of this research was to begin to understand if faculty members impact college student alcohol use. Specifically, exploring what students recall about faculty communication related to alcohol use, and the value students place on faculty expectations and communication related to their alcohol use. The findings were generated through adding five additional questions to an already existing survey instrument that was utilized on a biennial basis to collect alcohol and other drug perception and use data from students at 11 different campuses in a statewide higher education system. Findings indicated that most students never or rarely recall faculty communicating about alcohol. Men at two-year institutions were more likely to report having heard faculty communicate about alcohol use and were also more likely to report instructors? expectations as an effective way to limit or control their alcohol use. The more drinks students report per week the less effective they report faculty expectations as a way to limit or control their alcohol use; also an increase in the number of drinks per week decreased the likelihood they would change their behavior based on instructors? expectations. This study provides evidence that engaging faculty members in prevention efforts by relying on them to communicate expectations and low-risk drinking messages to students may not be as effective as suggested. There is some promise with enlisting the help of faculty with prevention efforts at smaller institutions or within cohort-based academic programs, where the same students and faculty members interact frequently. Focused training with faculty members at these smaller institutions could possibly enhance the positive impact.

Prenatal alcohol exposure (PAE) can lead to fetal alcohol spectrum disorder (FASD). FASD refers to a range of lifelong conditions caused by PAE, characterised by a distinctive facial phenotype, growth deficiencies and/or neurobehavioural impairments. This thesis presents four studies that I conducted to address knowledge gaps relevant to the epidemiology of PAE and FASD. First, objective measures of PAE are essential for identifying children at risk of adverse outcomes. Biomarkers have been advocated for use in universal PAE screening programs but their validity had not been comprehensively evaluated. I conducted a systematic review and found that biomarker test performance varied widely across studies. The quality of published studies was low, resulting in insufficient evidence to support the use of objective measures of PAE in practice. Second, the prevalence of FASD in the UK was unknown. Active case ascertainment studies have not been possible due to funding and ethical issues. To overcome these issues, I developed an algorithm to estimate FASD prevalence using existing data from a population-based birth cohort in England (ALSPAC). Up to 17% of children met criteria for FASD, indicating that it is a significant public health concern. Third, although PAE is the sole necessary cause of FASD, it is not always sufficient. Understanding risk factors for FASD is important for informing prevention strategies. However, existing studies have mostly been limited to discussion of association, rather than causation. I produced a causal diagram to depict hypothesised causal pathways to FASD. I used this diagram to guide analyses in a FASD risk factor study, reported below. Finally, I investigated FASD risk factors using multivariable logistic regression within the ALSPAC cohort. Prenatal stress, smoking and mental health problems increased the odds of FASD. Social support and folic acid supplementation were protective. These results indicate novel potential targets for FASD intervention.

Peer crowd affiliation (PCA) has been linked to alcohol use in adolescents, with patterns varying by crowd. However, a comprehensive examination of how peers influence college students’ behaviors, especially with regards to PCA, is lacking. The current study seeks to replicate and extend findings from Barber, Eccles, and Stone (2001) by examining whether high school PCA is associated with average weekly drinking and problematic drinking in a sample of college freshman, including friends’ drinking as a potential mediator and susceptibility to peer influence as a potential moderator. As existing research has found that close friends’ drinking predicts own drinking, peer influence may be the mechanism by which PCA is associated with alcohol use and problems in college. College students (N = 490) completed questionnaires assessing high school PCA, problematic drinking, and alcohol use habits among 3 close college friends, as well as a life history calendar of alcohol use. Hypotheses were tested using Preacher & Hayes bootstrapping mediation approach and Structural Equation Modeling (SEM). Results indicated positive associations between affiliation with Popular or Jock crowds and weekly and problematic drinking in college, and negative associations for affiliation with the Brain crowd. Support for mediation by friends’ alcohol use was found.

Excessive alcohol use is a significant public health problem globally. Alcohol use typically begins in adolescence or early adult life, and effective prevention strategies focused on this age group are needed to avoid initiation of harmful drinking. The aims of this PhD are to understand the epidemiology of alcohol use and alcohol use disorders (AUD) in East Africa, to validate self-reported alcohol use among young people in Tanzania, and to use the findings to recommend strategies for the prevention or reduction of harmful alcohol use among young people. Specific objectives include (1) to systematically review the evidence on alcohol use among young people in eastern Africa; (2) to estimate the prevalence of alcohol use, AUD and associated risk factors among different groups of young-people in northern Tanzania; (3) to assess the validity of self-reported alcohol use against the blood biomarker phosphatidylethanol (PEth); and (4) to assess the validity of the Mini International Neuropsychiatric Interview questionnaire (MINI) for the diagnosis of alcohol dependence against PEth, in Mwanza (northern Tanzania). The main findings are a high prevalence of reported alcohol use among diverse groups of young people in eastern Africa, especially among university students and sex workers, but that few studies used standardised alcohol screening questionnaires. In our survey of almost 2000 young people in northern Tanzania, the prevalence of reported alcohol use was higher among males (20-45% for current use) than females (12-47% for current use). Alcohol use was also associated with being in a relationship, greater disposable income, and a higher number of sexual partners. There were significant positive correlations between reported total alcohol intake and PEth concentration in males (Spearman correlation (rs)=0.65 among college students and rs=0.57 among casual labourers; p < 0.001). Self-reported alcohol use in the past month was also a sensitive marker of having a positive PEth result (overall sensitivity 89%, 95%CI 81-94%), and was similar in all groups. The MINI dependence criteria (positive responses to ≥3 questions) were met by 79/202 (39%) casual workers and college students. The high prevalence was mainly due to two non-specific questions (on tolerance and compulsion to drink). Both sensitivity and specificity of the MINI were low when compared to PEth, raising questions about the validity of the tool for this population. This thesis finds that alcohol use is a significant problem among young people in northern Tanzania, and the Timeline Followback calendar (TLFB) and Alcohol Use Disorders Identification Test (AUDIT) are sensitive measures of alcohol use. Most affected groups are college students and casual labourers. These two groups need urgent interventions addressing both individual and societal risks to reduce hazardous/harmful alcohol use.

Altering alcohol expectancies has reduced alcohol use among college students and may lead to successful prevention of alcohol use among high school students. We randomly assigned 379 12th-grade students to an expectancy challenge, traditional alcohol information, or control condition, and used Individual Differences Scaling to map expectancies into memory network format with Preference Mapping to model likely paths of association. After expectancy and traditional alcohol interventions, higher drinking male participants exhibited a greater likelihood to associate alcohol use with negative and sedating consequences and a decreased likelihood to associate alcohol with positive and arousing consequences. Drinking decreases paralleled the magnitude of changes in their likely path of expectancy activation. Children and adults who emphasize negative and sedating effects have been found to be less likely to use alcohol. Therefore, expectancy challenge interventions that have been successful at modifying expectancies and subsequently decreasing alcohol consumption among heavy drinking college students may be useful in the development of prevention curricula for high school students.
Ph.D.
Department of Psychology
Sciences
Psychology

Objective: To examine health services use on the basis of alcohol consumption. Material and Methods: A cross-sectional study was carried out on patients visiting the Primary Health Care (PHC) settings in Catalonia during 2011 and 2012; these patients had a history of alcohol consumption. Information about outpatient visits in the PHC setting, hospitalizations, specialists’ visits and emergency room visits for the year 2013 was obtained from 2 databases (the Information System for the Development of Research in PHC and the Catalan Health Surveillance System). Risky drinkers were defined as those who consumed more than 280 g per week for men or more than 170 g per week for women, or any amount of alcohol while being involved in a high risk work activity, or taking medication that significantly interferes with alcohol or when being pregnant. Binge drinkers (>60 g in men or >50 g in women in a short amount of time more than once a month) were also considered risky drinkers. Results: A total of 606,948 patients reported consuming alcohol (of which 10.5% were risky drinkers). Risky drinkers were more likely to be admitted to hospitals or emergency departments (range of ORs 1.08–1.18) compared to light drinkers. Male risky drinkers used fewer PHC services than male light drinkers (OR 0.89, 95% CI 0.87–0.92). In general, risky alcohol users used services more and had longer hospital stays. When stratifying by socioeconomic level of the residential area, we found that risky drinking failed significance, while current or past cigarette smoking was associated with higher healthcare use. Conclusions: Risky drinkers use more expensive services, such as hospitals and emergency rooms, but not PHC services, which may suggest that prevention strategies and alcohol interventions should also be implemented in those settings.

The thesis explores influences of the alcohol-specific (e.g. alcohol use, attitudes) and nonalcohol-specific (e.g. relationship quality) family environment on similarity and differences in adolescent siblings' alcohol use. Previous research has shown the importance of siblings for adolescent adjustment (Plomin & Daniels, 1987; Rowe & Gulley, 1992). However, research exploring family influences on siblings' alcohol use is scarce in the UK. Using a variety of theoretical perspectives, this thesis attempts to make a comprehensive account of family influence. Social learning principles (Bandura, 1977) such as modelling-imitation and reinforcement (via attitudes, norms) are considered as alcohol-specific mechanisms within families, accounting for similarity in parent-child dyads and sibling pairs. Regarding the influence of the non-alcohol-specific family environment, it is drawn on family systems theory (Minuchin, 1985), stresses and strains on parenting, and differential parenting approaches. This explores interrelations between marital, parent-child, and sibling relationships, and adolescent alcohol use (Hetherington et ah, 1999) within which models of siblings' differential intrafamilial experiences are integrated. Particular attention is given to the role of gender throughout this thesis. The study reported here used a cross-sectional design. It included 116 intact families, applying a multiple informant approach. During home visits, each parent and two siblings (younger siblings: 11-15 years, older siblings: 14-19 years) completed standardised questionnaires on demographics, alcohol/substance use, attitudes, family relationships, and other aspects of adolescents' life, combining self-reports and perceptions of others. The analysis is divided into three results sections and employs a variety of statistical methods (descriptive statistics, correlational and regression analyses, analysis of variance). Descriptive results (Chapter 5) of the level of family members' alcohol/substance use indicate that both parental and adolescents' use was lower than national surveys suggest. Differences in individual family members' self-reports and perceptions of the family environment support the use of self-reports of alcohol use and repeated analysis employing parent and child reports of family relationships. Findings on the alcohol-specific environment (Chapter 6) confirmed social learning processes. Male adolescents' alcohol use was related to parental and brothers' modelling, with parental norms being influential for older males' consumption. No such associations emerged for females regarding their parents or sisters. Older siblings' supply of alcohol was significantly associated with younger siblings' (excessive) alcohol use, but only among same-sex siblings. Neither parental alcohol norms nor perceived sanctions of adolescent alcohol use varied as a function of sibling gender similarity, but same-sex siblings experienced stricter parental alcohol norms than mixed-sex pairs. In relation to the non-alcohol-specific family environment (Chapter 7), parental alcohol use showed few disruptive effects on parenting behaviour. Marital quality affected the parent-child relationships of both siblings which in turn predicted sibling relationship quality, suggesting congruence in the quality among these family subsystems. Parenting toward each adolescent influenced this child's alcohol involvement. Younger adolescents showed lower alcohol use when their older sibling was exposed to marital discord. Generally, receiving the more favourable treatment relative to one's sibling resulted in lower alcohol involvement relative to this sibling. Sibling gender similarity moderated the siblings' level of monitoring and associations within the difference score models. Overall, the findings demonstrate the importance of the wider family environment for siblings' alcohol use and the role of gender in processes of social influence. Both parents and siblings provide opportunities for social learning of alcohol use. Child-specific experiences were the best predictors of adolescent alcohol use. However, the similarity in the climate of various family relationships reflects the importance of shared, family-level influences. Implications for alcohol education and prevention and recommendations for further research are discussed.

Of growing interest in the study of sexual minority experiences is the concept of community connectedness. Community connectedness reflects the cognitive and affective components of being affiliated with a particular community of similar others. Within the limited work that has been done, lesbian, gay, bisexual, and transgender (LGBT) community connectedness has typically been looked at as a predictor of positive outcomes, such as increased psychological well-being. However, there is limited evidence that LGBT community connectedness may be related to higher levels of substance use. This study aimed to explore the relationship that LGBT community connectedness has with alcohol use, taking into account a variety of potential confounding variables, including race, socioeconomic status, religiosity, and positive feelings towards one's sexual orientation. A total of 243 sexual minority participants (19.8% asexual, 29.2% bisexual, 22.2% gay/lesbian, 16.0% pansexual, and 12.8% other) were gathered through the use of targeted online social media advertising. A directed acyclic graph (DAG) was created to identify implications regarding variable covariance. Following the creation of the DAG, the implications were tested using bivariate correlations and the DAG was adjusted based on significant statistical relationships between variables. After the testing of the implications, we tested the hypothesis that LGBT community connectedness would predict alcohol use by regressing alcohol use on community connectedness controlling for the confounding variables identified using the DAG (age, LGB positive identity, race, religiosity, SES, and sexual orientation). The variables accounted for 11.37% variance in alcohol use, and higher community connectedness predicted more alcohol use (b=0.81, SEB=0.33, p=0.01). While connection to the LGBT community is typically explored as a positive form of social support, the current work found positive relationship between community connectedness and alcohol use for sexual minorities. The relationship between LGBT community connectedness and alcohol use should be explored in more depth to understand the pathways between a sense of connection and alcohol use. The work may indicate the need for non-alcohol based LGBT spaces to be more prevalent, so that community connection is not reliant on the use of alcohol-based spaces such as gay bars.

Context: There are two ways that digital media may influence alcohol use. The first is commercial alcohol marketing. The second is user-created alcohol promotion, defined as content distributed through new media that promotes consumption, but independent of commercial marketing. This thesis explores how both types of content promote alcohol, what association there is between exposure and alcohol-related attitudes and behaviour, and the differences between marketing and user-created promotion. Method: A mixed method design was employed, divided into two studies. The first was a content analysis of the design features, topical references, and messages suggested about alcohol in digital marketing and user-created promotion on Facebook, Twitter, and YouTube. The second was a cross-sectional survey with young adults (n = 405). This measured awareness of, and participation with, digital marketing and user-created promotion, and the association with consumption, higher-risk drinking, brand recall, expectancies, and drinking motives. Results: The content analysis found that digital marketing had personalised designs which contained subtle and positive messages about consumption, whereas user-created promotion had simpler designs, displayed little ethical practice, and contained overt messages about higher-risk drinking. The cross-sectional survey found that young adults were aware of, and participating with, both digital marketing and user-created promotion, with exposure greater for the latter. Exposure to both types of content was positively associated with alcohol use, higher-risk consumption, and drinking intentions. User-created promotion had a stronger association with all outcomes than marketing. The association between exposure and consumption, for both types of content, was mediated through drinking motives and expectancies. Conclusion: Young adults are aware of, and participating with, a range of digital marketing and user-created promotion. That such exposure is associated with alcohol-related attitudes and behaviour highlights the potential of new media to influence alcohol consumption. Further research is required to better understand young people’s experience with digital media and the challenges of addressing online health risk messages.

Alcohol use among community dwelling older adults is fast becoming a major health concern in Canada. It is fast becoming a major precursor for social dysfunction as many have experienced destructive relationships, financial despair, and social isolation. This population often falls victim to ageist views held by health care providers, delaying recognition and assistance in relation to alcohol misuse. Perhaps the most important gap is the lack of qualitative research that will study the experience of alcohol misuse in older adults from their perspective and try to understand their readiness for change. This critical ethnography explored the attitudes, beliefs, behaviours, and experiences of alcohol use among community dwelling older adults within their social, cultural, or political context with an aim to elicit a change during the process. Data were collected through semi-structured interviews with a total of eighteen individuals; 1) study participants (N=11) that were older adults and dwelled in an urban center in the Interior of British Columbia, and who used alcohol, and 2) key informants (N=7) who had extensive experience with substance use issues working in a variety of fields within the community. Audio-taped interviews were transcribed and analyzed. Using Carspecken’s framework of analysis, three main themes and thirteen subthemes were identified. This study examined the role of environmental factors early in older adults’ life and their influence in forming beliefs, attitudes, and behaviours, related to alcohol use later in life. It examined the older adults’ drinking patterns, consequences of alcohol use, additional substance use, and barriers to seeking assistance. Findings in this study indicated that early adverse life experiences increase the chances of alcohol misuse later in life. Adjunct use of other substances indicated the changing characteristics of this population and the potential increase in health care costs as baby boomers become a predominant faction of the older adult population. Results of the study indicated improved access to nursing services at the primary health care level, a change of physicians’ attitudes, increased resources, and community support would encourage this population to seek out help. These themes have implications for nursing practice, education, nursing administration, and further research.
Applied Science, Faculty of
Nursing, School of
Graduate

Alcohol use among college students is often in the news. Some scholars argue, with literature to support it, that problem drinking in college is just a media-driven myth (Lederman et al. 2004). Yet it is clear that college students do drink, some to excess. Various reasons are cited from alcohol availability to the "freedom" associated with this stage of life. However, very few researchers have attempted to determine whether religiosity affects alcohol use among college students. The purpose of this study was to further examine the combined issues of religiosity and alcohol use among college students. Is excessive use of alcohol during this time of life simply an adult transition issue, as Jackson et al. (2005) contend, or is there more to it? Research seems to point to the fact that religiosity plays a role. The primary hypothesis tested was that students who valued religious activities as part of their college experience would use alcohol less, including binge drinking, than those who did not. The second hypothesis tested was that students who valued parties and Greek life would use alcohol and binge more than students who did not. The data set used was constructed by the Harvard School of Public Health and included data from 120 four-year colleges and universities from throughout the United States. The analysis supported the hypothesis that religiosity was a factor in reduced alcohol use by college students. College students who valued religious activities drank less than those who did not. The study also supported the hypothesis that students who valued parties and Greek life drank more. The heaviest drinkers were those who valued parties. These results are highly significant given the size of the sample. No other study that looked at religiosity and alcohol use among college students used a sample this large. These results help us to better understand the negative association between religiosity and alcohol use among college students as well as the positive association between parties and alcohol use. They especially help us to formulate strategies that might be considered to alleviate problem drinking during this stage of life.

The proposed study examined whether negative urgency and positive urgency are dynamic traits that hold bi-directional relationships with binge and prolonged alcohol use across time. Individuals between the ages of 18-30 were recruited from Amazon Mechanical Turk (MTurk; n = 179) and university student (n = 66) pools. Participants completed three batteries of self-report assessments approximately 30 days apart, each containing measures assessing negative and positive urgency, as well as drinking frequency and binge behavior during the prior month. Latent variable cross-lagged panel models examined the effects of alcohol use from the previous month on negative and positive urgency while controlling for concurrent and autoregressive effects. Results of the current study indicated that for the full sample, there was not an effect for the influence of binge/prolonged drinking on either negative or positive urgency during the subsequent month. However, when examined separately by sample (Turkers vs. university) and gender (male vs. female), significant effects were found more for individuals who were Turkers, male, and/or heavy drinkers, suggesting that increases in positive and negative urgency at Time 2 could be partially explained by variance in drinking patterns at Time 1 for these individuals. However, these relationships were not replicated again between Time 2 and Time 3 due to a decrease in all drinking behaviors during these times. Lastly, the study found that while urgency scores were related to psychosocial problems and dependence symptoms associated with drinking, there was no evidence to support that urgency scores had substantial relationships to specific frequency and/or bingeing behavior across the overall sample, although positive urgency had support for a relationship with bingeing, particularly among heavily drinking men. Thus, while the primary findings did not indicate any effects for a general sample of young adults, the effects observed among heavy male drinkers in the present study add to a growing body of literature indicating potential for interactive effects among personality, environmental, and sociobiological factors across the trajectory of the human lifespan. Future research that continues to examine urgency and how it relates to alcohol use in longitudinal contexts, utilizing diverse samples, is warranted.

Like adolescents, young adults are at risk of initiating tobacco use and escalating to daily use and tobacco dependence. However, not every young adult who uses cigarettes intermittently becomes tobacco dependent, and the time-course of those who transition to daily use varies widely. Individual differences likely contribute to the variability observed in patterns of tobacco use. This dissertation uses a multi-modal research approach to examine dimensions of impulsivity and alcohol use that are associated with vulnerability for escalation of cigarette smoking, and whether alcohol’s effects on behavioral disinhibition impact cigarette consumption. Study 1 investigated the associations between dimensions of trait impulsivity, alcohol use, and smoking behavior in a cross-sectional sample of young adults who varied in frequency of cigarette smoking. Study 2 expanded on the results of Study 1 by examining the separate and combined effects of impulsivity and alcohol use on escalation of tobacco use in a longitudinal study of young adults in their first three years of college to determine whether alcohol use and dimensions of impulsivity influenced trajectories of smoking behavior, and whether alcohol use and behavioral impulsivity changed across time as a function of tobacco use trajectories. Study 3 utilized a randomized, within-subject, placebo controlled design to examine whether alcohol-induced impairments in behavioral inhibition mediated the relationship between acute alcohol administration and ad-libitum cigarette consumption. Results from studies 1 and 2 indicated that alcohol use was associated with smoking frequency, and that dimensions of impulsivity (i.e. sensation seeking, lack of premeditation, and urgency) differentiated smoking groups. Study 3 found that acute alcohol increased smoking behavior, but alcohol impairment of inhibitory control did not mediate the relationship between alcohol and smoking consumption. Taken together, the results of these studies demonstrate that alcohol use and impulsivity play a significant role in tobacco use escalation, though more research is needed to determine the mechanism(s) that drive alcohol-induced increases in cigarette consumption.

Extensive documentation exists which firmly establishes the high use rates and disastrous consequences of alcohol consumption by university students. Use rates for this population have been linked to attitudes toward alcohol consumption, especially alcohol expectancies. Research to date on alcohol expectancies has shown differences in expectancies among various groups. However much of this research has been conducted without a theoretical basis, accomplishing little in explaining how beliefs and drinking behavior are related. The investigation was designed to explore the relationships among and between early recollections and alcohol expectancies and to explore how the contents of early recollections function in relation to expectancies in terms of alcohol consumption patterns among three groups of college males (student-athletes, fraternity men, and independents). The content of individuals' early recollections was analyzed and compared to expectancies and consumption rates for each of the three groups. The study addressed seven hypotheses regarding alcohol consumption rate comparisons, comparisons of consequences experienced as a result of alcohol consumption, comparisons of alcohol expectancies, and comparisons of reported content of early recollections. Multiple regression analysis was utilized to test the extent to which select early recollections and alcohol expectancy scores contributed to the explained variance in alcohol consumption patterns.

Alcohol is frequently co-administered with other psychotropic substances, yet little is known about patterns of alcohol use in a simultaneous polysubstance context. In the present dissertation concomitant alcohol-drug administration is examined with an emphasis on delineating patterns of alcohol use when it is co-administered with psychostimulant drugs known to interact with neural mechanisms believed to be involved in mediating alcohol's ascending limb reinforcing effects: midbrain dopamine transmission.
In two retrospective self-report studies polysubstance users reported on their simultaneous use of drugs and alcohol. Results revealed that alcohol was commonly co-administered with various abused substances, particularly with psychostimulant drugs that are known to increase dopamine neurotransmission, and there was an identifiable pattern of administration that was characterized by initial alcohol consumption preceding repeated intermingled alcohol-psychostimulant administrations which resulted in alcohol dose escalation.
In a third study, the effects of administering the psychostimulant drug nicotine on alcohol intake was directly examined using a double-blind placebo controlled self-administration procedure. Nicotine was found to significantly increase alcohol ingestion.
In a final study we examined the effect of decreasing dopamine neurotransmission on alcohol self-administration by using a dietary manipulation that depletes the nutritional precursors to dopamine. This procedure was found to decrease alcohol consumption, an effect that was especially evident in a subset of drinkers thought to be hypersensitive alcohol's ascending limb dopamine effects. Overall findings suggest that alcohol co-administration with psychostimulant drugs affects patterns of alcohol intake and that this may be the result of an interaction involving dopamine neurotransmission.

Thesis (Ph. D.)--Dept. of Psychology. University of Missouri--Kansas City, 2004.
"A dissertation in health psychology and psychology." Advisor: C. Keith Haddock. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed Feb. 28, 2006. Includes bibliographical references (leaves 129-135). Online version of the print edition.

Although alcohol plays an important role in psychiatric morbidity, there is a general lack of strategies within psychiatric care to intervene at alcohol problems in an early stage (secondary prevention). The aim of this thesis was to increase knowledge of adequate forms of secondary alcohol prevention in psychiatric care.   The capacity of three brief screening instruments was investigated in a psychiatric outpatient sample (n=1811). The results indicate that the HED (heavy episodic drinking) screener, strongly recommended for health care settings, is not sufficiently sensitive in a psychiatric setting. Instead, the full AUDIT (Alcohol Use Disorders Identification Test) is recommended. The knowledge and attitudes of psychiatric staff members to problem-drinking patients were studied and the effects of a three-hour training course were investigated. Confidence in self-perceived capacity to intervene in more severe alcohol problems was raised among all staff after training. Awareness of early signs of problem drinking was raised among psychologists and social workers. The therapeutic attitude of the psychiatric staff was higher when compared with primary care staff. Two forms of brief intervention were delivered by clinical psychiatric staff. At 12 months, 29% of all participants had improved their drinking habits, moving from hazardous to non-hazardous level (21%) or from harmful to hazardous level (8%). In the improved group, mean AUDIT score was reduced from 11.0 points at baseline to 5.5 points. Differences in outcome between the two interventions could not be identified. Nine high-risk drinking young female psychiatric patients were interviewed, focusing on reasons for excessive drinking and factors facilitating a change in drinking habits. Alcohol played an important role in the lives of the young women. It made them feel social and helped them deal with unbearable emotions. It was also used as a means of self-harm, representing the first stage in an escalating self-harm process. They expressed a need for help from their caregivers in addressing the underlying reasons for drinking. Secondary alcohol prevention strategies including appropriate screening methods, staff training and the elaboration of tailored interventions are urgently needed in psychiatric care. The findings of this thesis can be used when forming such strategies.

Alcohol use disorder (AUD) is a widespread mental disease denoted by chronic alcohol use despite significant negative consequences for a person’s life. It affected more than 14 million persons in Europe alone and accounted for more than 5% of deaths worldwide in 2011-2012. Understanding the psychological and neurobiological mechanisms driving the development and maintenance of pathological alcohol use is key to conceptualizing new programs for prevention and therapy of AUD. There has been a variety of etiological models trying to describe and relate these mechanisms. Lately, the view of AUD as a disorder of learning and decision making has received much support proposing dual systems to be at work in AUD – one system being deliberate, forward-planning, and goal-directed and the other one reflexive, automatic, and habitual. Both systems supposedly work in parallel in a framework of value-based decision making and their balance can be flexibly adjusted in healthy agents, while a progressive imbalance favoring habitual over goal-directed choice strategies is assumed in AUD. This imbalance has been theoretically associated to neural adaptations to chronic alcohol use in corticostriatal pathways involved in reward processing, especially in ventral striatum. However, these theoretical models are grounded strongly on animal research while empirical research in the human domain remains rather sparse and inconclusive. Furthermore, alterations in value-based decision-making processes and their neural implementation might not only result from prolonged alcohol misuse but may also represent premorbid interindividual differences posing a risk factor for the development of AUD. Therefore, I here present three studies investigating the relation of alcohol use with the balance between goal-directed and habitual decision systems and with parameters modulating option valuation processes of these systems, namely delay, risk, and valence of option outcomes. To separate the investigation of these decision processes as predisposing risk for or consequence of alcohol use, two samples were examined: one sample of 201 eighteen-year-old men being neither abstinent from nor dependent on alcohol as well as one sample of 114 AUD patients in detoxification treatment and 98 control participants matched for age, sex, educational background, and smoking status. Both samples had a baseline assessment of several behavioral tasks, questionnaires, and neuropsychological testing and were followed-up over one year to examine drinking trajectories in the sample of young men and relapse in detoxified patients. The behavioral tasks included a sequential choice task using model-free and model-based reinforcement learning as operationalization of habitual and goal-directed decision making, respectively, during functional magnetic resonance imaging and four tasks probing participants’ delay discounting, probability discounting for gains and losses, and loss aversion. Study 1 presents the cross-sectional analysis of the sequential choice task in relation to baseline drinking behavior of the young-adult sample. These analyses did not reveal an association between non-pathological alcohol use and habitual and goal-directed control on neither a behavioral nor neural level except for one exploratory finding of increased BOLD responses to model-free habitual learning signals in participants with earlier onset of drinking. Study 2 examined the same task in AUD patients compared to control participants showing no difference in behavioral control or neural correlates between those groups. However, prospectively relapsing AUD patients showed lower BOLD responses associated to model-based goal-directed control than abstaining patients and control participants. Additionally, the interaction of goal-directed control and positive expectancies of alcohol effects discriminated subsequently relapsing and abstaining patients revealing an increased risk of relapse for those patients who showed higher levels of goal-directed control and low alcohol expectancies or low levels of goal-directedness and high expectancies. Study 3 examined modulating features of goal-directed and habitual option valuation – delay, risk, and valence of options – in association to alcohol use in the young-adult sample and AUD status in the sample of patients and matched control participants on a cross-sectional as well as longitudinal level. This study revealed no relation of delay, risk, and loss aversion with current alcohol use and consumption one year later in the young men. In contrast, AUD patients showed systematically more impulsive choice behavior than control participants in all four tasks: a higher preference for immediate rewards, more risky choices when facing gains and less when facing losses, and lower loss aversion. Furthermore, a general tendency to overestimate the probability of uncertain losses could predict relapse risk over the following year in AUD patients. Taken together, these results do not support the hypothesis that mechanisms of value-based decision making might be predisposing risk factors for alcohol consumption. The findings for patients already suffering from AUD are mixed: while choice biases regarding delays, risks, and valence of option outcomes seem to be altered systematically in AUD, there was no indication of an imbalance of habitual and goal-directed control. These findings challenge the assumption of a generalized outcome-unspecific shift of behavioral control from goal-directed to habitual strategies during the development of AUD and point towards several possible future avenues of research to modify or extend the theoretical model.

How do professional men experience alcohol? It is the intention in this thesis to explore professional men’s experiences of alcohol. Twelve professional men aged between forty and fifty who drink at a minimum of one occasion per week were interviewed. Their narratives were then analysed qualitatively using the Grounded Theory approach from a social constructionist perspective. Six categories emerged from the data including the Core Category: Learning to Maintain the Equilibrium: Experiencing Alcohol through a Process of Maturation. Maintaining the Equilibrium represents the balance between the positive and negative attributes of alcohol, where the individual weighs up the costs and benefits of drinking in the light of experience. Implicit within the core category is the concept of the Tipping Point. Professional men recognise this as representing the significant point where the benefits of alcohol tip over into the costs. Learning is the process that continues throughout the lifespan, and achieving this balance is realised through a process of Maturation. Maturation refers to the process of growing older at the same time as gaining knowledge, insight and wisdom from experience. This core category incorporates the other significant categories. These are as follows: Learning: this represents the on-going process by which individuals learn about alcohol through the early experiences of the family, teenage drinking, past and present drinking occasions; Appraising captures the cognitive processes that individuals employ to evaluate the benefits and disadvantages of drinking; Balancing highlights the decision-making process where participants weigh up the costs and benefits of drinking; Regulating encapsulates participants’ strategies and personal rules which they employ to regulate their alcohol use; and finally Personal Attributes examines the internal and external assets that individuals possess which both motivate and enable professional men to moderate their drinking. The current literature on alcohol studies is primarily focussed on problem-drinking and gives little insight into normative drinking. Accordingly, it fails to provide a detailed understanding of professional men’s experiences of alcohol and the reinforcing mechanisms which enable professional men to moderate their alcohol use. Therefore, this in-depth qualitative study aims to redress this imbalance. The findings of this study are discussed in terms of the existing theories on alcohol use and misuse, and can be been to expand on the current research literature on alcohol and the modifying variables which impact on drinking behaviour.

Alcohol use among university students is a worldwide social and clinical reality. Understanding and addressing this phenomena is an imperative recognised by the government of South Africa and its Higher Education institutions, where student drinking has a plethora of negative consequences. This study builds on the work of Young and de Klerk (2012) with Rhodes University students by adding drinking motives to their findings of demographic correlates. The motivational model of alcohol use (Cox & Klinger, 1988) posits that drinking motives are a proximal predictor of alcohol use. The model further delineates four drinking motives (social, enhancement, coping, and conformity) which are hypothesized to lead to phenomenological distinct patterns of alcohol use. An online survey method was utilized to collect data and a representative sample of 501 students participated. Descriptive and inferential statistics were computed to address five research questions: (1) to establishing the current alcohol use trend; (2) to investigate the demographic factors associated with alcohol use; (3) to describe students‘ drinking motives; (4) to explore the correlates of drinking motives; and, finally, the primary aim was (5) to investigate whether students‘ drinking motives predicted alcohol use when controlling for the effects of descriptive drinking norms and demographic variables. The results indicate that 68.5% of participants currently consume alcohol, and 51.0 % of these drinking students consume five or more drinks during a drinking session. 20.7 % of the drinking students used alcohol at the harmful or alcohol dependent levels. Increased alcohol use was associated more with males, undergraduates, early onset drinkers, more disposable income, and students‘ perceptions of their peers‘ drinking. Students endorsed enhancement motives marginally more than social motives, followed by coping and conformity motives. Males, early onset drinkers, black students, and at risk (of alcohol use disorders) students endorsed more motives, especially social and enhancement motives. Of primary concern was the role of drinking motives on alcohol use after controlling for the effects of descriptive drinking norms. The four block hierarchical regression model which was run explained 38% of the variance in alcohol use. Drinking motives, particularly enhancement motives, displayed a statistically significant impact on alcohol use adding 11% to the variance. Additionally, age of alcohol use onset, monthly pocket money, age, and gender predicted alcohol use separately. The results of this study indicate that alcohol use has multi-factorial influences. Of note, the results confirmed the motivational model of alcohol use by indicating that alcohol use is partially motivational and that drinking behaviour is not a unitary phenomenon but instead it represents heterogeneity based on the affective change individuals anticipate to gain by drinking. The high binging rate (51%) among this sample may speak to the greater endorsement of enhancement motives, which have been shown in previous studies to be associated with heavy drinking. Enhancement motives are attempts to attain positive affect which, due to the psychoactive properties of alcohol, require greater consumption and intoxication. Additionally, as a result of the greater quantities of alcohol, individuals who drink for enhancement motives would be more prone to alcohol consequences. The results suggest that a multi-level intervention framework targeting individual students, the university community, and the surrounding community, is indicated. Furthermore, intervention may be tailored-made to address specific drinking motives.

The purpose of the thesis is twofold (a) to review the relationship between alcohol use and emotion regulation, and (b) to develop and evaluate a newly designed questionnaire calIed the Brief Aspirations and Concerns in Life Inventory (BACLI) for measuring the structure of an individuals motivation for obtaining their life goals. First, this thesis presents a review of alcohol's roles in regulating emotions. This review paper proposes an integration of Cox and Klinger's (1988, 1990,2004) motivational model of alcohol use and Gross and Thompson's (2007) model of emotion regulation strategies. It aims to further the understanding of alcohol's role in regulating emotions. Tentative conclusions are made that alcohol can be used to enhance some emotion regulation strategies, albeit in many cases maladaptively. The empirical paper compares the outcomes and relationships between the BACLI questionnaire and a well-established and comprehensive Personal Concerns Inventory (PCI; Cox & Klinger, 2000). It also examines the relationship between other motivational and emotional variables and alcohol use and problems. The BACLI provided a good alternative to the PCI. In line with previous research, motivational variables were predictive of alcohol use and problems. Difficulties with emotion regulation also predicted greater drinking problems. Finally, these papers are discussed in terms of their implications for clinical psychology.

This study examined the effect of the experience of a loss on alcohol use and drinking motives in a college sample. Participants for this study were drawn from the “Spit for Science” project (Dick et al., 2014). The sample included 3,013 students (31.8% men, 68.2% women; 44.3% White, 21.1% Black, 19.6% Asian, 6.0% Latinx; mean age = 18.96; 16.2% bereaved) from Virginia Commonwealth University. Data were collected from participants’ freshman spring and sophomore spring time points on the Life Events Checklist, Alcohol Consumption items, and Drinking Motives Questionnaire-Revised. Participants who were bereaved between the freshman and sophomore timepoint did not significantly differ in their alcohol consumption, coping drinking motives, or conformity drinking motives compared to their non-bereaved counterparts. Limitations and future directions for research are reviewed.

All human beings experience emotion. However a number of individuals have difficulties recognizing, processing and regulating their emotions. This set of emotional "deficits' is classified as alexithymia, a multifaceted personality construct consisting of difficulties identifying feelings (DIF), difficulties describing feelings (DDF) and externally oriented thinking (EOT). The prevalence rate of alexithymia in alcohol use disorders is between 45 to 67%. A number of hypotheses related to the role of alexithymia in alcohol-dependence have been proposed, and it has been hypothesised that those with alexithymia use alcohol as a coping mechanism for stress, to become more assertive or improve interpersonal functioning. Yet, few research studies have comprehensively investigated alexithymia in alcohol­dependence. A lack of a theoretical framework examining alexithymia and alcohol is also apparent. Attachment theory and particularly parental bonding is considered a critical factor in the aetiology and development of alexithymia, but this hypothesis has not been thoroughly investigated. Thus, the purpose of Study 1 using meta-analysis was to explore, clarify and report the strength of the relationship between parenting style and alexithymia. The evidence indicated moderate to strong relationships of maternal care with overall alexithymia score, DDF and DIF. Moderate relationships were reported for maternal overprotection with DDF and overall alexithymia score. Moderate associations between paternal overprotection, DDF and total alexithymia score were also found. The findings of Study 1 confirmed an important association between maternal care and key elements of alexithymia, and highlighted the potential of attachment as a theoretical :framework for further research on alexithymia and alcohol-dependence. The objective of Study 2 was to explore the factorial validity of the Toronto Alexithymia Scale (TAS-20), the most commonly used assessment tool for alexithymia, in a sample of210 alcohol-dependent individuals. This group of participants had an alcohol use disorder diagnosis and were attending a Cognitive Behavioral Treatment (CBT) outpatient program. Data from this sample was used in Studies 2, 3, 4 and 5 with minor variations in the actual number of participants in each of these studies. Confirmatory factor analyses were conducted using Structural Equation Modelling to evaluate the factor structure of the TAS-20. Based on previously reported factor structures, both a two-factor and a three-factor model were examined, using maximum likelihood estimation. Four of the five fit indices and a chi-square difference test indicated a superior fit for the three-factor model compared to the two-factor model. Taken together these findings demonstrated that the original three-factor model of the TAS-20 was a more plausible fit to the data than the two­factor model. Given alexithymia's high prevalence in alcohol use disorders, valid assessment tools are critical. Study 2 confirmed the factorial validity of a self-report measure of alexithymia, the TAS-20. An objective assessment, the Observer Alexithymia Scale (OAS), has also been recommended to increase the validity of data collected. The objective of Study 3 was therefore to assess the validity and reliability of the Observer Alexithymia Scale (OAS) and the TAS-20. Data from the same 210 alcohol-dependent participants was used for Study 3. These participants were administered the TAS-20 at assessment and upon treatment completion at 12 weeks. Clinical psychologists provided observer assessment data for a subsample of 159 patients. The findings confirmed acceptable internal consistency, test-retest reliability and scale homogeneity for both the OAS and TAS-20. The TAS-20 was more strongly associated with alcohol-dependence than the OAS and also provided stronger predictive utility towards alcohol-dependence. Problems with the discriminant and convergent validity of the OAS were evident. These findings suggest that the T AS-20 was a more psychometrically robust instrument to measure alexithymia in alcohol use disorder outpatients compared to the OAS. A number of studies have examined alexithymia in relation to alcohol use disorders, yet there has been a lack of a theoretical framework to explore essential mechanisms in the link between alexithymia and alcohol-dependence. Study 4 introduced an integrative framework of attachment and expectancy theory, and examined theoretical relationships between attachment, alexithymia, alcohol expectancies and alcohol-dependence, in the same sample of 230 alcohol-dependent participants. Path analyses were conducted via Hierarchical Regression Analyses (for observed variables) and Structural Equation Modelling (for latent variables). Attachment was a significant predictor of alexithymia, but not for alcohol-dependence. There was also a significant prediction of DIF for the alcohol expectancy domain Assertion. The relationship between DIF and alcohol-dependence was partially mediated through the alcohol expectancy Affective Change, a key mechanism that contributes to our understanding of the link between DIF and alcohol-dependence. Taken together, these findings confirmed the importance of Affective Change in elucidating the highly rewarding effects of alcohol in those with combined alexithymia and alcohol-­dependence. Given that alexithymia may have an impact on the adherence and efficacy of psychological treatments, Study 5 examined potential differences on sociodemographic variables, alexithymia, attachment, alcohol expectancies, mood, craving and measures of alcohol-dependence between those who completed treatment and non-completers. The relationship between alexithymia and craving was also examined at baseline and at 12 week follow-up. Two hundred and eighty six consecutively treated participants diagnosed with an alcohol use disorder in an outpatient CBT program were included in the present study. There were significant differences between completers and non-completers on age, alcohol problem severity, dependent attachment, overall alexithymia score and DIF. This indicated more severe alcohol-dependence and attachment issues as well as higher levels of alexithymia in non-completers. Significant correlations between alexithymia, DIF and craving were evident as well as a significant relationship between DDF at baseline and craving at 12-week follow-up. To date, this is the first study to investigate alexithymia in relation to craving among those with alcohol-dependence, and suggests that a lack of emotional insight and confusion about feelings are associated with a stronger desire to drink alcohol. These findings highlight the potential importance of alexithymia in relation to treatment completion, and further research is needed to elucidate the role of alexithymia in relation to more standardised treatment outcome variables among those with alcohol use disorders. The developmental social-cognitive model presented partially integrates expectancy theory within attachment theory and for the first time provides a unified model to examine alexithymia in alcohol use disorders. The theoretical and clinical implications of this model are discussed in relation to a theoretical extension, molecular genetic factors, treatment approaches and future prevention of alcohol­dependence.

The enzyme ADH-A and one of its mutants ADH-A C1B1 from ​ Rhodococcus ruber,​ have in previous studies been proved to act as proper biocatalysts, fully capable of performing redox reactions. Two redox reactions were studied during this project, were those enzymes act as catalysts. For that matter, ADH-A wild type and ADH-A C1B1 genes were expressed in ​ E. coli​ and the encoded enzymes were purified and used for kinetic studies with a final goal on studying the kinetic isotope effect that is generated between them and the molecules that contain deuterium. HPLC analysis on these products showed that the reactions were not thermodynamically favored and conclusions on the best reaction conditions for both enzymes as well as for further improvements are discussed.

PSYCHOLOGICAL CORRELATES OF TOBACCO, ALCOHOL AND DRUG USE AMONG ADOLESCENTS KarakaS, Ö
zge M.S., Department of Psychology Supervisor: Assoc. Prof. Belgin AyvaSik July 2006, 130 pages The aim of the present study was to identify sociodemographic and psychological correlates of adolescent tobacco, alcohol and drug use. Participants were 854 high school students (485 girls, 369 boys) aged between 14-18. Participants were administered a Demographic Information Form, Arnett Inventory of Sensation Seeking, seven subscales of Drug Use Screening Inventory (DUSI) and Tobacco, Alcohol and Drug Use Questionnaire. Twelve point two percent of the students reported cigarette use, 23.5 % reported alcohol use and 2.3 % reported illicit drug use at least once in their lives. Independent Samples t-test Analysis revealed that smokers received higher scores than non-smokers on sensation seeking, psychiatric disorder, behavior patterns, school performance / adjustment, peer relations, family system and leisure subscales of DUSI but there was not a significant difference between smokers and non-smokers in terms of social competency. Also, it was found that both alcohol users scored higher than non-users on sensation seeking, psychiatric disorder, behavior patterns, school performance / adjustment, peer relations, family system but there was not a significant difference between alcohol users and non-users in terms of scores on leisure and social competency. Drug users scored significantly higher than randomly selected non-users on sensation seeking, behavior patterns and peer relations scales. Logistic regression analysis revealed that adolescent smoking was predicted by gender, age, G.P.A., place of birth, peer smoking, behavior patterns, social competency, school problems and family relations. Besides, alcohol use was predicted by gender, age, number of siblings, maternal education, peer smoking, peer alcohol use, social competency, school performance / adjustment and family relations. Findings are discussed within the context of the relevant literature.