Дисертації з теми "Asthma Australia"

Includes CD-ROM inside back cover of volume 2. Bibliography: p. 178-222. Aims to identify current risk factors for asthma and to determine which of these factors, at the population level, is associated with asthma prevalence in children in South Australia. In addition, modelling techniques are used to determine which factors are significant predictors of asthma prevalence in 4 to 5 year old children in S.A. Study results show that at the population level, 9 risk factors are significantly associated with lifetime prevalence and 24 factors with period prevalence. Study findings are generally consistent with existing literature.

Doctor of Philosophy
Excerpt Chapter 2 - A review of the literature has revealed that asthma management practices in the Australian community are currently suboptimal resulting in significant morbidity and mortality. In adolescent asthma there are added challenges, with problems of self-image, denial and non-adherence to therapy where self-management skills assume a greater importance (Forero et al 1996, Price 1996, Brook and Tepper 1997, Buston and Wood 2000, Kyngäs et al 2000). In rural and remote areas in Australia, asthma management practices have been shown to be poorer and mortality rates from asthma are considerably higher compared to metropolitan areas (AIHW ACAM 2005, AIHW 2006). Limited access and chronic shortages of specialist services in rural areas are shifting the burden more and more towards the primary sector (AIHW 2006). It becomes paramount that people with asthma in rural settings become involved in self-management of their asthma and that community based health care providers be more proactive in facilitating these self-management behaviours by appropriate education and counselling. Health promotion activities, which are a broad range of activities including health education, have been acknowledged as having the potential to improve the health status of rural populations (National Rural Health Alliance 2002). Community pharmacy settings have been shown to be effective sites for the delivery of health promotion, screening and education programs (Anderson 2000, Elliott et al 2002, Cote et al 2003, Hourihan et al 2003, Watson et al 2003, Boyle et al 2004, Goode et al 2004, Paluck et al 2004, Sunderland et al 2004, Chambers et al 2005, Saini et al 2006). In the case of asthma, outreach programs have been shown to have beneficial effects in terms of reducing hospital admissions and emergency visits and improved asthma outcomes (Greineder et al 1995, Stout et al 1998, Kelly et al 2000, Legorreta et al 2000, Lin et al 2004). We proposed to extend the role of the community pharmacist beyond the traditional realm of the “pharmacy” into the community in rural Australia with the first asthma outreach programs designed for community pharmacy. The outreach programs were designed to include two health promotion strategies, the first targeting adolescents in high schools and the second targeting the general community. The project aimed firstly, to assess the feasibility of using community pharmacists to deliver two asthma outreach programs, one targeting adolescents and one for the wider community in a rural area and secondly, to assess the programs’ impact on adolescent asthma knowledge and requests for information at the community pharmacy. Excerpt Chapter 3 - Patient education is one of the six critical elements to successful long-term asthma management included in international and national asthma management guidelines, which have emphasised education as a process underpinning the understanding associated with appropriate medication use, the need for regular review, and self-management on the part of the person with asthma (Boulet et al 1999, National Asthma Council 2002, National Asthma Education and Prevention Program 2002, British Thoracic Society 2003, NHLBI/WHO 2005). The ongoing process of asthma education is considered necessary for helping people with asthma gain the knowledge, skills, confidence and motivation to control their own asthma. Since most health care professionals are key providers of asthma education, their knowledge of asthma and asthma management practices often needs to be updated through continuing education. This is to ensure that the education provided to the patient conforms to best practice guidelines. Moreover, health care professionals need to tailor this education to the patients’ needs and determine if the education provided results in an improvement in asthma knowledge. A review of the literature has revealed that a number of questionnaires have been developed that assess the asthma knowledge of parents of children with asthma (Parcel et al 1980, Fitzclarence and Henry 1990, Brook et al 1993, Moosa and Henley 1997, Ho et al 2003), adults with asthma (Wigal et al 1993, Allen and Jones 1998, Allen et al 2000, Bertolotti et al 2001), children with asthma (Parcel et al 1980, Wade et al 1997), or the general public (Grant et al 1999). However, the existing asthma knowledge questionnaires have several limitations. The only validated asthma knowledge questionnaire was developed in 1990 and hence, out of date with current asthma management guidelines (Fitzclarence and Henry 1990). The shortcomings of the other knowledge questionnaires relate to the lack of evidence of the validity (Wade et al 1997, Grant et al 1999, Bertolotti et al 2001), being outdated 81 with current concepts of asthma (Parcel et al 1980) or having been tested on small or inadequately characterised subject samples e.g. subject samples consisting of mainly middle class and well educated parents (Brook et al 1993, Wigal et al 1993, Moosa and Henley 1997, Allen and Jones 1998, Allen et al 2000, Ho et al 2003). Furthermore, most of the published asthma knowledge questionnaires have been designed to assess the asthma knowledge of the consumer (i.e. a lay person with asthma or a parent/carer of a person with asthma). There is no questionnaire specifically developed to assess the asthma knowledge of health care professionals, who are key providers of asthma education. It is hence important to have a reliable and validated instrument to be able to assess education needs and to measure the impact of training programs on asthma knowledge of health care professionals as well. An asthma knowledge questionnaire for health care professionals might also be used to gauge how successful dissemination and implementation of guidelines have been. Excerpt Chapter 4 - Asthma self-management education for adults that includes information about asthma and self-management, self-monitoring, a written action plan and regular medical review has been shown to be effective in improving asthma outcomes (Gibson et al 1999). These interventions have been delivered mostly in a hospital setting and have utilised individual and/or group formats. Fewer interventions have been delivered in a primary care setting, usually by qualified practice nurses and/or general practitioners or asthma educators and, to date, their success has not been established (Fay et al 2002, Gibson et al 2003). Community pharmacy provides a strategic venue for the provision of patient education about asthma. Traditionally, patient education provided by community pharmacists has been individualised. However, group education has been shown to be as effective as individualised education with the added benefits of being simpler, more cost effective and better received by patients and educators (Wilson et al 1993, Wilson 1997). While small group education has been shown to improve asthma outcomes (Snyder et al 1987, Bailey et al 1990, Wilson et al 1993, Yoon et al 1993, Allen et al 1995, Kotses et al 1995, Berg et al 1997, de Oliveira et al 1999, Marabini et al 2002), to date, no small-group asthma education provided by pharmacists in the community pharmacy setting has been implemented and evaluated.

[Truncated abstract] In Australia, asthma is a common chronic illness, which often requires complex treatment regimens. This study used an anthropological perspective to explore the experience of people living with asthma, with the specific aim of contributing to the health care programs offered to people living with asthma. The study was conducted in an Australian city (Perth, Western Australia). The foci of the study were Australian lay people, from the general community, living with asthma, and a small number of non- English speaking Vietnamese-Australian migrants. Some spouses of the Australians and biomedical practitioners were also included. Questionnaires, and particularly indepth interviews, were used to explore the explanatory models of asthma for doctors and lay people with the condition. The explanatory models of the doctors focused primarily on assessing and treating the physiological dimension of asthma, and educating patients. The explanatory models for lay people with asthma reflected their everyday reality: in addition to its impact on their physical health, asthma affected their daily life, social roles and participation, and their personal identity. Placing the experience of asthma in this wider perspective showed that the Australians used practical reasoning to make a trade-off between using medication, such that they felt safe from `attacks? and could `do all they wanted to do?, and minimising their `dependence? on potentially harmful medications. Responding to acute episodes involved a risk assessment in which people weighing the health risk of waiting against the social risk of seeking help unnecessarily. For the Vietnamese- Australians, caring for asthma was strongly shaped by their social position as non- English speaking migrants. They lacked access to information about asthma and to specialist care. They had sufficient medication, but were ill-informed about how to use their medicines effectively and safely: in general, the Vietnamese people were overmedicated but under-serviced in the care of their asthma. Beyond explanatory models, the Australian participants (lay people and doctors) shared a cultural model of asthma as a chronic illness. This Australian cultural model shaped the experience and care of asthma. It included concepts such as framing the past as an adjustment process, and the present as `living normally? with asthma. Taking care of asthma was expressed as `taking control? of asthma, so a person could minimise the illness and still be healthy. The Vietnamese-Australians did not share this cultural model of asthma as a chronic illness, as reflected in their expression of the hardship asthma created in limiting their ability to work hard for their family, and how they expected a cure for their condition from biomedicine. The Australians also shared a cultural model of health that was derived, in part, from the health promotion messages that are targeted at lay people. These promotional messages were the basis of a morality in health: people shared an implicit understanding that a person deserved health, and assistance when ill, when he/she displayed the required self-discipline in performing health behaviours.

[Truncated abstract] Background: Genetic epidemiology draws on the mechanisms of heredity and the reproductive characteristics of populations to formulate methods to investigate the role of genetic factors and their interaction with the environment in disease aetiology. Asthma and atopy are complex genetic disorders and are among the most common diseases to affect the developed world. Twin studies provide an elegant means of disentangling genetic and environmental contributions to the aetiology of conditions that have a significant impact on the health of the general population in ways that cannot be achieved by any other study design, by comparing disease frequency in monozygotic (MZ) or identical twins, who share 100% of their genes with that in dizygotic (DZ) or non-identical twins who share, on average, 50% of their genes. Twin-family studies allow the complete partitioning of phenotypic variation into components representing additive genetic, dominance, shared environment and non-shared environment. ... For twin family data, the best fitting model was the one which included additive genetic effects and either genetic dominance or shared sibling environment, and that shared family environment was not important. With respect to asthma in WA twin families, there are no reasons to conclude that the EEA is not valid. Conclusions: The WA Twin Register is the first population-based register of childhood multiples to be established in Australia, and the WATCH study is one of only a few population-based twin-family studies in the world. Families who participated in the WATCH study were no different from non-participants with respect to social class and there was no difference in the prevalence of DDA in WATCH study twins and either their singleton siblings or the general population of WA children. Results from the GEE models replicate those found in numerous studies from many different countries. The BUGS models developed have been shown to produce consistent results with both simulated and real data sets and offer alternative methods of analyzing twin and twin-family data. By including an extra term in the partitioning of the variance to account for the environment effect of being a MZ twin, a numerical value is calculated for the difference in MZ and DZ correlation with respect to the phenotype examined, which allows the validity of the EEA to be directly assessed.

[Truncated abstract] This thesis describes the epidemiology and outcome of acute asthma managed by ambulance paramedics, in the metropolitan area of Perth, Western Australia, for the period of 1990 to 2001. The primary aim of this thesis was to determine demographic, socio-economic and clinical trends for ambulance transported patients with asthma, their outcomes and how they have changed over time. The Perth metropolitan area, located in the south-western corner of Western Australia (WA), accounts for 72% of the state’s population, which was approximately 1.3 million people at Census 2001. This thesis was structured around the analysis of twelve years of St John Ambulance (WA) data. Ambulance data was linked using probabilistic matching techniques to the Western Australian Data Linkage System, custodian of links to thirty five years of morbidity and mortality data of the state’s population . . . Unique geography, a monopolistic ambulance service and access to extensive linked data provided ideal conditions for this population-based epidemiological study of patients with asthma who were transported by ambulance. Observed trends in age and gender characteristics of patients, ambulance codes and temporal variables appear to be consistent over time. Monitoring trends in the use of ventilation procedures recorded in hospital data provided useful indicators for describing the epidemiology of severe, lifethreatening asthma in the prehospital setting. Findings from this study were found to be consistent with published literature.

This thesis provides supporting evidence for the role of the microbiome in asthma and allergy in the context of contrasting environments, Eastern/developing versus Westernised/developed environment. The Westernised environment has reshaped the microbial composition profile of human microbiomes, and these altered microbiomes are more likely to contribute to the increased rates of asthma and allergy.

[Truncated abstract] Asthma is a chronic and complex disorder and despite our increase in the understanding of the genetics, pathology and mechanisms underlying asthma a gold standard definition of asthma does not exist. A criterion for recognising and diagnosing asthma in epidemiological studies is crucial in order to determine risk factors for disease. Prospective longitudinal birth cohort studies have increased our understanding of the natural history and risk factors for asthma, yet we are still not able to accurately predict which children will go on to have asthma as adults. It is during the transition from childhood to adolescence where factors underlying asthma change and the prevalence of asthma shifts between the sexes. There are inconsistencies regarding risk factors for the development and persistence of disease during this transitional period. Risk factors predicting the development and persistence of asthma and intermediate phenotypes (BHR, airway inflammation and atopy) may be influenced by gender and risk factors predicting disease may differ between childhood and adolescence. Aims 1. To identify risk factors for Asthma, BHR and Atopy at 14yrs of age. 2. To determine risk factors for persistence of asthma between 6 and 14 years. 3. To examine the influence of gender on risk factors during adolescence. Method The West Australian Pregnancy Cohort is a longitudinal birth cohort. The cohort initially consisted of 2868 live births with follow-ups at 1, 2, 3, 6, 8, 10 and 14 years of V age. ... Strong associations were seen with BHR and new diagnosis of wheeze and asthma in VI teenagers. Interestingly having either a cat or dog inside was protective for persistence of disease; in particular stronger associations were seen in teenage girls not in boys. During this transitional period the risk factors for asthma and intermediate phenotypes differ between the sexes. Different mechanisms are likely to be involved in determining asthma in boys and girls during adolescence and shed new light on the recognised switch in the gender balance in asthma prevalence from the male predominance in childhood to the female predominance in adult life. Our understanding of the natural course of disease from the prenatal period to adulthood and the identification of the various asthma phenotypes has the potential to change prognosis and planning of therapeutic strategies. Identifying those at high risk for persistence of disease in the early stages of life will allow therapeutic interventions to be more appropriately targeted.

In rural inland, south-eastern Australia, allergy to the fungus Alternaria is prevalent and an important risk factor for asthma. The aim of the thesis was to investigate the distribution and factors influencing allergens of Alternaria in the air. As airborne allergenic spores were thought to arise from harvesting of nearby crops, two towns with different agricultural practices were studied. Moree has two crop harvesting periods in summer and autumn whilst Wagga Wagga has one harvesting period in summer. Over two years, air was sampled daily in Wagga Wagga and Moree using Burkard traps. The reliability of measurements from a single site to represent the distribution of airborne concentrations of spores across each town was examined using data from three traps simultaneously, sited 2.0 to 4.9 km apart, over four weeks. Substantial intra-class correlation coefficients (ICC) were observed between the three sampling sites across both towns (ICC=0.52, 95% CI 0.30-0.71 to 0.76, 95% CI 0.61-0.87) when counts of Alternaria spores were relatively high. The correlation was poor when counts were low. Of more than 365 trap tapes examined, the two microscopic traverses strongly correlated for counts of Alternaria spores (ICC=0.95, 95% CI 0.94-0.96). Alternaria was detected in both towns throughout the two year period with peaks in spore concentrations reflecting the season of crop harvesting in each region. Individual exposure to spores was examined. Thirty three subjects (adults and children from nine families) wore nasal air samplers and personal air samplers both inside and outside their homes. The effects of activity, location, age on the inhalation of Alternaria spores and variation between individuals in the same environment were determined. Every subject inhaled Alternaria spores. Personal exposure to Alternaria in the home environment varied substantially between subjects. Levels of fungal spores inhaled were higher during periods of activity than during rest, and higher while subjects were outdoors than indoors. During outdoor activity, the number of Alternaria spores inhaled ranged from 4 to 794 (median 11) spores/hr. Sources of airborne spores was investigated by sampling air above wheat and cotton crops near the towns during harvesting and non-harvesting periods, in a grain and cotton seed storage shed, and a cotton gin. Substantially higher concentrations were detected above crops during harvesting periods compared to non-harvesting periods. Peaks were associated with harvesting and other activities where plants were manipulated. By regression analysis spore concentrations in both towns were modelled against those detected above crops and with weather variables. Only one crop sampling period (cotton harvest) independently correlated with concentrations in town. Analysis combining all data showed concentrations of spores above crops correlated with spore concentrations in the town when lagged by one day. Variables of rainfall and maximum temperature influenced concentrations in both towns, and wind direction in Wagga Wagga alone. Parents of asthmatic children were asked by questionnaire in which locations symptoms were provoked. Asthma was reported to be exacerbated at grain farms and with disturbance of local vegetation in town and home gardens. Nasal sampling confirmed that activities that disturbed dust or vegetation increased the inhalation of spores. The factors that release allergen from spores were determined in a modified Halogen immunoassay. Approximately 60% of spores released allergen, and the proportion was influenced by isolate, nutrient availability, viability, and not influenced by sunlight or culture age up to 21 days. Germinating the spores significantly increased the proportion that released total allergen and Alt a 1 (p<0.0001). Alt a 1 appears to be a minor contributor to the total allergen released from spores except when spores have germinated. Conclusions: People living in inland rural regions of Australia are exposed to substantial quantities of allergenic spores of Alternaria. Exposure is a highly personal event and is largely determined by disturbance of local vegetation releasing spores such as from nearby crops by wind, harvesting, slashing, transport and processing of produce, and from within town and home gardens. Most spores inhaled are likely to be allergenic, with potency potentially increasing with viability.

Although morbidity and mortality from asthma decreased in recent years, the burden of the disease remains considerable. The fetal origins of adult disease hypothesis claims that exposure at critical periods in fetal life may alter susceptibility to disease later in life. Numerous studies examined the association between maternal diet and pregnancy outcomes or child atopic disease with often conflicting results. This phenomenon may be due to considerable variation in study populations, sample size, study design, confounding control, and other methodological issues. Dietary influences on disease may also differ for different subgroups of atopic sensitization. This Thesis investigates the later issue in a novel way. Further, no previous study has investigated whether the effect of maternal diet on child asthma is mediated through or independent of the infant anthropometric status or non-milk fluids are associated with asthma. Methods: The 1988-89 Tasmanian Infant Health Survey (initially designed to study Sudden Infant Death Syndrome) provided data on the maternal diet during pregnancy and infant anthropometric measures. A semi-quantitative food frequency questionnaire collected data on maternal intake of protein, fat, carbohydrate, calcium, iron, magnesium, zinc, vitamin A, vitamin C, {u03C9}-3 and {u03C9}-6 polyunsaturated fatty acids, and dietary supplements. The anthropometric variables of interest included birthweight, birth length, head circumference, placental weight and derived indices. Childhood questionnaires administered during the 1995 Childhood Asthma Survey and 1997 Childhood Asthma and Respiratory Health Study collected information on atopic outcomes of wheezing, asthma, eczema, and hay fever. House dust mite (HDM) and ryegrass sensitization were defined by skin prick testing. Adjusted odds ratios (AORs) and their 95% confidence intervals (CIs) were derived from logistic regression models, and adjusted relative risks (ARRs) and their 95% CIs - from generalised linear models with log link function and binomial error structure. Associations between continuous dependent and independent variables were examined by multiple linear regression. The contribution of infant anthropometric status to the change in the magnitude of association between a nutritional risk factor and child asthma was calculated by the proportionate decline in the excess risk. Reliability of maternal recall was measured by kappa (k) and weighted kappa (kw). Results: This study found that an increase of 10g of absolute maternal protein intake per day was associated with a reduction in birthweight of 17.8g (95% CI: -32.7, -3.0, p = 0.02). Protein intake was also associated negatively with ponderal index ({u00DF} = -0.01, 95% CI: -0.02, -0.00, p = 0.01) and positively with relative head circumference ({u00DF} = 0.05, 95% CI: 0.01, 0.10, p = 0.02). A greater risk of asthma was found in infants who were heavier (AOR: 1.34, 95% CI: 1.10, 1.62), longer (AOR: 1.36, 95% CI: 1.12, 1.66) or fatter (AOR: 1.24, 95% CI: 1.02, 1.52) at birth as measured by standard deviation scores of these anthropometric variables. An increased risk of asthma was also associated with intakes of protein (AOR: 1.83, 95% CI: 1.13, 2.95), zinc (AOR: 1.08, 95% CI: 1.01, 1.15), {u03C9}-3 polyunsaturated fatty acids (AOR 1.6, 95% CI: 1.1, 2.4) and nuts (AOR: 2.04, 95% CI: 1.04, 4.00). Higher vitamin C intake decreased the risk of asthma hospitalization (AOR: 0.28; 95% CI: 0.08, 0.98). Birth length, head circumference and placental weight substantially ({u2265}10%) altered the magnitude of associations between selected nutrients and recent wheeze, any atopic sensitization, HDM sensitization, and, to a lesser extent, ryegrass sensitization. The findings suggest that different dietary factors may influence sensitization to different allergens differently. Specifically, a significant association between child fish intake and ryegrass-pure (AOR: 0.37; 95% CI: 0.15, 0.90) but not HDM-pure sensitization (AOR: 0.87, 95% CI: 0.36, 2.13) was found. In contrast, breastfeeding appeared to be protective against HDM (ARR: 0.71, 95% CI: 0.51, 0.99) but not ryegrass (ARR: 0.63, 95% CI: 0.28, 1.46) sensitization. Furthermore, breastfeeding was protective against asthma linked to HDM (ARR: 0.25, 95% CI: 0.07, 0.85) but not ryegrass (ARR: 0.81, 95% CI: 0.46, 1.43) sensitisation. None of the non-milk fluids appeared to be a significant predictor of asthma. When reliability of recalled infant nutrition was analysed, breastfeeding duration was recalled better (kw = 0.86) than the age of solids introduction (kw = 0.36-0.46). Presence of asthma and related conditions altered the reproducibility of recalling solids but not breastfeeding. Conclusions: This study raised the possibility that the effect of high protein in altering infant anthropometry at birth may involve changes in body composition. Examined for the first time, non-milk fluids did not appear to be significant predictors of asthma. Another important contribution from this Thesis was demonstration of the differential effect of diet for sensitization to different aeroallergens. Lastly, the Thesis showed poor agreement between prospective and retrospective reports of the age of solids introduction. The modest effect of maternal nutrition on the pregnancy outcome and child asthma found here is not surprising because associations in nutritional epidemiology are often of small magnitude and are susceptible to confounding bias and misclassification of dietary intake and disease outcome. Difficulty in separating maternal factors from environmental influences during pregnancy and the multifactorial aetiology of asthma may also play a role. Understanding what maternal nutrition constitutes optimal will help refine dietary recommendations. Due to ethical and practical difficulties, observational cohort studies, as reported here, will remain an important source of new knowledge. Greater understanding of molecular and genetic mechanisms involved in asthma should also be a considerable part of future research.

Masters Research - Masters of Philosophy (Midwifery)
Asthma continues to be one of the most common potentially serious conditions that can complicate pregnancy. At least 12% of pregnant women in Australia are affected by asthma. Many studies have examined the link between poorly controlled asthma and increased exacerbations during pregnancy with increased foetal and maternal morbidity. Despite asthma management guidelines advocating a collaborative approach to antenatal asthma management among health professionals, the role of the midwife in antenatal asthma management has not previously been examined. This study set out to explore what midwives currently know about asthma in pregnancy and their perceived role in antenatal asthma management. A qualitative descriptive design was used and data were collected via face-to-face interviews with 13 midwives who consented to participate in the study. Data collected from these interviews were digitally recorded, transcribed and analysed using qualitative content analysis. The findings from these data are as follows: that midwives’ current knowledge about asthma in pregnancy varies among the sample group with some participants having an awareness of possible changes in asthma symptoms during pregnancy but few participants knowing the range of potential consequences of poor asthma management for both mother and baby. The perceived role of midwives in antenatal asthma management also varies with some midwives stating that they feel their role is to educate women regarding their asthma and others stating that their role is to refer women to other health professionals. Barriers to providing antenatal asthma management were also identified by the midwives. Participants also offered suggested solutions to the barriers that were identified. Overall, there was found to be no uniform approach to the antenatal asthma management being undertaken in the facility in which this study took place. The development of an antenatal asthma clinical pathway could help to change current clinical practice regarding asthma management of pregnant women, and make that process more uniform. Increasing opportunities for asthma education for those who provide antenatal asthma management could also help determine the role of the midwife when caring for a pregnant woman with asthma. The findings of this study also have implications for further research into the role of the midwives working with women who have complex needs during the antenatal period.

Research Doctorate - Doctor of Philosophy (PhD)
‘Population ageing’ raises many challenges for governments, such as continued and prolonged workforce participation of men and women over their life course. This research aimed to i) identify and compare workforce participation patterns of men and women over the life course; ii) investigate the associations between workforce participation patterns, early life factors and adult life factors over the life course; iii) explore longitudinal associations between chronic diseases and workforce patterns, while considering the influence of various health and socio-demographic factors. Three different data sources – the ‘45 and Up Study’, the Australian ‘Life History and Health Survey’ and the ‘Australian Longitudinal Study on Women’s Health’ were used. Latent class analysis (LCA), LCA with classify-analyse approach, logistic regression and multinomial regression were used in five different studies to identify and explore patterns of workforce participation and its different associations over the life course, with a gendered perspective. Findings from the studies indicate that workforce participation patterns over the life course are very different for men and women. While men were found to be mostly engaged in full time paid work, women were more likely to work part time. Also, many men may decrease work after age 55, and many women had lower workforce participation over the life course. The work patterns of young women without children were very similar to men – majority working full time. Chronic diseases (diabetes, asthma, depression and arthritis) and other early and adult life factors were associated with work patterns. However, these associations varied by gender and also dependent on how men and women responded to their long term health issues and various circumstances affecting them over the life course. Therefore, it is important to consider the role of gender in shaping workforce patterns and their association with chronic diseases over the life course.

Research Doctorate - Doctor of Philosophy (PhD)
Asthma Prevalence is higher in Australia Compared with global rates with older women having the highest frequency of the disease. In older people asthma is found to be a different phenotype with more severe symptoms resulting in worse outcomes and higher mortality rates. Given that there is an increasing trend in global ageing which is associated with elevated prevalence of chronic diseases including asthma and ageing of baby boomers in Australia, there is need for research on asthma in older population especially older women. This thesis aimed to I) investigate the impact of asthma on mortality for older women while considering confounding factors; II) examine self-reported health service use for older women according to asthma status; III) investigate cross sectional and longitudinal associations between asthma groups and self-reported health service use, adjusting for predisposing, enabling and needs factors; IV) examine Medicare records for health service use by older women according to asthma status; and V) investigate cross sectional and longitudinal associations between asthma groups and Medicare for health service use while also considering predisposing factors, enabling factors and needs. Data from 1921-26 and 1946-51 cohorts of the Australian Longitudinal study on women's health linked with Medicare records were used in analyses of this thesis. Women were categorised into five mutually exclusive groups according to their asthma status (percentages shown for 1921-26 and 1946-51 cohorts respectively): 1) past asthma (4.2% and 6.4%); 2) prevalent asthma (8.5% and 10.2%); 3) incident asthma (5.3% and 8.9%); 4) bronchitis/emphysema (17.6% and 15.2%); and 5) never asthma (64.4% and 59.3%). Logistic regression and multinomial regressions were used to investigate the cross sectional associations between asthma groups and both Self-reported and administrative health service use taking into account the effect of predisposing, enabling and needs factors. Longitudinal analyses were conducted to investigate the association of asthma groups with health service use by older women over time adjusting for repeated measures of predisposing, enabling and needs factors. Findings from the studies showed that asthma was associated with higher mortality rates in older women from the 1921-26 cohort even after taking into account the effect of confounding factors. Larger proportions of women with asthma in both cohorts had comorbidities including heart diseases, diabetes, anxiety and depression. Women with asthma were more likely to have reported visits to their GPs/family doctors in a year compared with women without asthma even after adjusting for predisposing, enabling and needs factors. This finding was corroborated by results from the Medicare records, showing that asthma was associated with more frequent and longer visits even after taking into account the effect of predisposing, enabling and needs factors. Asthma was also associated with higher number of claims for specialist visits, after-hours GP visits, Chronic Disease Management (CDM) and Asthma Cycle of Care (ACC) items. After adjusting for asthma group, the use of these services, were mostly driven by possessing private health insurance and comorbidities. Although women with asthma had higher levels of health service use, the uptake of enhanced primary care items including assessments, CDM and ACC were low. Potentially, the better uptake and application of services subsidised by these items could improve the impact of asthma on older women’s quality of life and reduce asthma mortality rates in older women.