Auswahl der wissenschaftlichen Literatur zum Thema „Light design. Light for bipolar disease. Circadian light“

Evidence for behavior modification for improved health outcomes was evaluated for nutrition, physical activity (PA), and indoor environmental quality (IEQ). The databases searched included LISTA, PubMed, and Web of Science, with articles rated using an a priori baseline score of 70/100 to establish inclusion. The initial search produced 52,847 articles, 63 of which were included in the qualitative synthesis. Thirteen articles met inclusion for nutrition: cafeteria interventions, single interventions, and vending interventions. Seventeen articles on physical activity were included: stair use, walking, and adjustable desks. For IEQ, 33 articles met inclusion: circadian disruption, view and natural light, and artificial light. A narrative synthesis was used to find meaningful connections across interventions with evidence contributing to health improvements. Commonalities throughout the nutrition studies included choice architecture, increasing the availability of healthy food items, and point-of-purchase food labeling. Interventions that promoted PA included stair use, sit/stand furniture, workplace exercise facilities and walking. Exposure to natural light and views of natural elements were found to increase PA and improve sleep quality. Overexposure to artificial light may cause circadian disruption, suppressing melatonin and increasing risks of cancers. Overall, design that encourages healthy behaviors may lower risks associated with chronic disease.

Background: Alzheimer's Disease (AD) is often accompanied by severe sleep problems and circadian rhythm disturbances which may to some extent be attributed to a dysfunction in the biological clock. The 24-h light/dark cycle is the strongest Zeitgeber for the biological clock. People with AD, however, often live in environments with inappropriate photic Zeitgebers. Timed bright light exposure may help to consolidate sleep- and circadian rest/activity rhythm problems in AD, and may be a low-risk alternative to pharmacological treatment. Objective & Method: In the present review, experts from several research disciplines summarized the results of twenty-seven light intervention studies which used wrist actigraphy to measure sleep and circadian activity in AD patients. Results: Taken together, the findings remain inconclusive with regard to beneficial light effects. However, the considered studies varied substantially with respect to the utilized light intervention, study design, and usage of actigraphy. The paper provides a comprehensive critical discussion of these issues. Conclusion: Fusing knowledge across complementary research disciplines has the potential to critically advance our understanding of the biological input of light on health and may contribute to architectural lighting designs in hospitals, as well as our homes and work environments.

Conservation of the energy equilibrium can be considered a dynamic process and variations of one component (energy intake or energy expenditure) cause biological and/or behavioral compensatory changes in the other part of the system. The interplay between energy demand and caloric intake appears designed to guarantee an adequate food supply in variable life contexts. The circadian rhythm plays a major role in systemic homeostasis by acting as “timekeeper” of the human body, under the control of central and peripheral clocks that regulate many physiological functions such as sleep, hunger and body temperature. Clock-associated biological processes anticipate the daily demands imposed by the environment, being synchronized under ideal physiologic conditions. Factors that interfere with the expected demand, including daily distribution of macronutrients, physical activity and light exposure, may disrupt the physiologic harmony between predicted and actual behavior. Such a desynchronization may favor the development of a wide range of disease-related processes, including obesity and its comorbidities. Evidence has been provided that the main components of 24-h EE may be affected by disruption of the circadian rhythm. The sleep pattern, meal timing and meal composition could mediate these effects. An increased understanding of the crosstalk between disruption of the circadian rhythm and energy balance may shed light on the pathophysiologic mechanisms underlying weight gain, which may eventually lead to design effective strategies to fight the obesity pandemic.

Abstract Introduction Sleep disturbances are common in elderly patients and may contribute to disease progression in certain populations (e.g., Alzheimer’s Disease). Light therapy is a simple and cost-effective intervention to improve sleep. Primary barriers to light therapy are 1) poor acceptability to use of devices and 2) inflexibility of current devices to deliver beyond a fixed spectrum and throughout the entirety of the day. However, dynamic, tunable lighting integrated into the native home lighting system can maximize short-wavelength light in the morning and minimize short-wavelength light in the evening, thus entraining circadian rhythms and treating sleep disturbances, and overcome these limitations. We determined the feasibility of implementing a whole-home tunable lighting system as a potential sleep intervention. Methods Tunable LED lights were installed throughout the homes of healthy older adults already enrolled in an existing study with embedded home assessment platforms (ORCATECH study; n=4 subjects in n=3 homes). In ORCATECH, continuous data on room location, activity, sleep, and general health parameters are collected at minute-to-minute resolution over months to years of participation. This single arm longitudinal design collected participants’ light usage in addition to ORCATECH outcome measures. Primary outcomes for this pilot study included the feasibility and patient acceptability. Exploratory outcomes were sleep metrics (sleep time, latency, efficiency), mobility (room transitions and actigraphy), and overall health indices (weekly body weight, self-report general health questionnaires) both pre- and post-intervention. Results Two subjects terminated the study citing technical difficulties with the lights and a preference for brighter illumination. Of the remaining 2 participants, sleep metrics were explored over a 12-month period spanning pre- and post-installation of lights. Nightly duration in bed was compared with minute-to-minute room entry data and actigraphy with high inter-measure reliability. Conclusion These data support that tunable whole-home lighting systems are reasonably acceptable and feasibly implemented using an automated platform for continuous data collection. Quantification of sleep over long periods of time is robust and reliable in the home environment of elderly subjects. These results will inform implementation of future large-scale lighting intervention studies in patients at risk for developing Alzheimer’s Disease. Support (if any) Hartford Gerontological Center Interprofessional Award, Pacific Northwest National Laboratory, OHSU ORCATECH

Abstract Background Visible light, predominantly in the blue range, affects mood and circadian rhythm partly by activation of the melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs). The light-induced responses of these ganglion cells can be evaluated by pupillometry. The study aimed to assess the blue light induced pupil constriction in patients with bipolar disorder (BD). Methods We investigated the pupillary responses to blue light by chromatic pupillometry in 31 patients with newly diagnosed bipolar disorder, 22 of their unaffected relatives and 35 healthy controls. Mood state was evaluated by interview-based ratings of depressive symptoms (Hamilton Depression Rating Scale) and (hypo-)manic symptoms (Young Mania Rating Scale). Results The ipRGC-mediated pupillary responses did not differ across the three groups, but subgroup analyses showed that patients in remission had reduced ipRGC-mediated responses compared with controls (9%, p = 0.04). Longer illness duration was associated with more pronounced ipRGC-responses (7% increase/10-year illness duration, p = 0.02). Conclusions The ipRGC-mediated pupil response to blue light was reduced in euthymic patients compared with controls and increased with longer disease duration. Longitudinal studies are needed to corroborate these potential associations with illness state and/or progression.

Chronopharmaceutical drug delivery systems release drug at a rhythm that ideally matches the biological requirement of a given disease therapy or prevention. The sound knowledge of the biological processes and their functions utilized in biomedical and pharmaceutical sciences is necessary for effective design and evaluation of pharmaceutical dosage forms. Circadian phase master the circadian clock of the body, the supra chiasmatic nucleus is known to regulate the endogenous circadian rhythms present inside the human body and the peak evidences of some diseases are reported as per circadian rhythm. The secretion of melatonin, a hormone, released by the pineal gland during darkness, help to reset the internal clock, which regulates the timing of different body functions. In certain diseases like asthma, airway resistance increases progressively in early morning, also release of adrenaline and noradrenaline in the morning causes rise in the blood pressure. In hypercholesterolemia, cholesterol synthesis is higher during the night time than day light; in diabetes mellitus blood sugar level is higher in the day time; myocardial insufficiency occurs early in the morning, and many others. The present review addresses the approaches to chronopharmaceuticals, identifies existing technologies, and study of recent chronopharmaceutical drug delivery systems for management of various chronic diseases like diabetes, hypertension and various types of cancers according to the circadian rhythms of diseases in order to optimize therapeutic outcomes and reduce side effects. Recently chronopharmaceutical drug delivery systems are attaining huge importance in the field of pharmaceutical technology for product development because they are proved to reduce dosing frequency, toxicity and also they deliver the drug in particular disease as and when required considering the peak time of the disease, offering better patient compliance.

Background and Hypothesis: Life on Earth has adapted to a 24-hour cycle of light and darkness. Circadian physiology coordinates temporal metabolism, hormone cycling, and sleep using clock genes. It is documented that dysregulation of clock gene expression is a key factor in the pathogenesis of diabetic retinopathy. Our goal was to explore the relationship between clock genes and the retina in diabetic milieu, and we hypothesized that disrupting downstream insulin signaling in a manner similar to diabetes in the retina would also affect the circadian clock. Experimental Design or Project Methods: In this mouse study, we used a Per2::Luc fusion protein to perform real-time bioluminescent recording of circadian rhythms. We used SecinH3 to inhibit Insulin Receptor Signaling (IRS-1). In isolated retinas, we modulated IRS-1 to mimic the diabetic condition of impaired insulin signaling; this allowed us to directly quantify circadian rhythms in the retina. Results: Our results show that IRS-1 inhibition by SecinH3 altered the gene expression of Per2, a clock regulatory gene, over the controls. There was an increase in the period and an apparent phase shift in the presence of 100uM SecinH3. Conclusion and Potential Impact: Our findings can help us understand the role of insulin signaling on circadian rhythms of the retina and provide another temporal dimension to view diabetic retinopathy disease progression. Ultimately, further studies and a closer understanding of the roles of molecular clocks and insulin signaling may help to develop novel therapeutics for treating some of the harmful effects of diabetes.

Research has showed that different light scenarios have a profound effect on hospitalized bipolar patients. Different light situations decrease the hospital stay for patients during both manic and depressive episodes. Nevertheless, a field study carried out during this thesis work of two arbitrary patient rooms in Swedish behavioral health clinics showed no incorporation of this knowledge in the light design of the rooms. Both patient rooms had insufficient light levels both in terms of circadian recommendations and perceived brightness. Hence this thesis suggests an improved light design for patient rooms housing bipolar patients. The basis of the improved design is to incorporate a dynamic, circadian lighting that varies depending on the patient's need and diagnosed episode.