Graduation date: 1953

Self-reported psychological distress is quite common in the Swedish elderly population. Feelings of psychological distress may have devastating consequences. The overall aim of this study was to explore associations between socioeconomic position and work complexity during midlife with psychological distress in old age. Ordered logistic regression was used to investigate the associations between, (I) socioeconomic position during midlife and psychological distress in old age, (II) work complexity during midlife and psychological distress in old age, (III) the association between socioeconomic position and psychological distress independent of work complexity, and (IV) the association between work complexity and psychological distress independent of socioeconomic position. The results show that (I) higher socioeconomic position during midlife is associated with less psychological distress in old age (II) higher work complexity during midlife is associated with less psychological distress in old age, and that (III) higher work complexity is associated to less psychological distress independent of socioeconomic position, (IV) but the association between socioeconomic position and psychological distress diminishes adjusting for work complexity. The main conclusion from this study is that individuals with high socioeconomic position benefits from both their position in society and from their working conditions while individuals of lower socioeconomic position are more likely to also suffer the drawbacks of disadvantageous working conditions in relation to late life psychological distress.

Thesis (Ph. D.)--University of California, San Diego and San Diego State University, 2002. / Vita. Includes bibliographical references (leaves 128-135).

Thesis (Ph.D.) -- University of Texas at Arlington, 2008.

Thesis (Ph. D.)--University of Oregon, 2003. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 157-170). Also available for download via the World Wide Web; free to University of Oregon users.

Thesis (Ph. D.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains viii, 90 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 54-67).

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

published_or_final_version / Public Health / Master / Master of Public Health

Background: Prior studies regarding the risk factors of mild cognitive impairment (MCI), such as physical activity (PA) and sleep related factors in older Chinese populations are scarce, and the findings have not been consistent. Objectives: 1. To cross-sectionally and longitudinally examine the dose-response association between PA and cognitive function by Delayed Word Recall Test (DWRT) or Mini-mental State Examination (MMSE). 2. To cross-sectionally and prospectively examine the association of sleep related factors, including sleep duration, daytime napping, morning tiredness and insomnia, with cognitive function. Design: Cross-sectional and longitudinal analysis using both baseline and follow-up data from the GBCS. Methods Baseline data from 8,451 men and 22,067 women aged 50 years or above were used for the cross-sectional analysis. Among them, 4,214 men and 11,284 women participating in the second examination were included in the longitudinal analysis. Information on demographic, socioeconomic and lifestyle factors, and personal disease history was collected. Cognitive function was assessed by MMSE and DWRT under standardized protocols. Results 1. Significant dose-response relations across quintiles of metabolic equivalent value (METs) with DWRT score in participants with or without good self-rated health were found in cross-sectional analysis (all P for trend <0.001). 2. Prospectively, compared to those who were physically active, those with moderate activity or inactivity had increased risk for MCI. Regarding daily walking time, subjects with walking of 0.5 to 1 h, or ≥1 h had significantly reduced risk of MCI by 25% and 31% respectively compared with those who walked < 0.5 h per day. Subjects with low PA level at both baseline and follow-up had a significantly higher risk of MCI than those reporting PA at both baseline and follow-up. 3. Cross-sectionally, after adjustment for a range of potential confounders, an inverted U-shaped association between sleep duration and DWRT score was found, with 7 to 8 h of habitual sleep duration showing the highest score (P-values for trend from 3 to 7 h and from 7 to ≥10 h were all ≤0.001). Subjects with daily napping, morning tiredness, or insomnia had lower DWRT score than those without (P ranged from <0.001 to 0.01). 4. Prospectively, after adjustment for multiple risk factors, compared to sleep duration of 7 hours per day, those with sleep duration of 5 hours or less had increased risk for MCI by 43%. The adjusted P value for the linear trend from sleep duration of 3 hours to 7 hours per day was 0.01. The association remained after excluding those with poor health status. No significant associations of daytime napping, morning tiredness and insomnia with MCI were found. Conclusions In summary, we found a significant dose response association between PA and cognitive function in both cross-sectional and longitudinal analysis. One hour of daily walking is recommended for older Chinese people to delay or prevent cognitive decline. Short or long sleep duration may also be an important predictor of mild cognitive impairment. Sleep duration of less than 6 hours per day may indicate an increase risk of cognitive impairment in older people. / published_or_final_version / Community Medicine / Doctoral / Doctor of Philosophy