Objectives To evaluate whether mid-life marital status is related to cognitive function in later life. Design Prospective population based study with an average follow-up of 21 years. Setting Kuopio and Joensuu regions in eastern Finland. Participants Participants were derived from random, population based samples previously investigated in 1972, 1977, 1982, or 1987; 1449 individuals (73%), aged 65-79, underwent re-examination in 1998. Main outcome measures Alzheimer’s disease and mild cognitive impairment. Results People cohabiting with a partner in mid-life (mean age 50.4) were less likely than all other categories (single, separated, or widowed) to show cognitive impairment later in life at ages 65-79. Those widowed or divorced in mid-life and still so at follow-up had three times the risk compared with married or cohabiting people. Those widowed both at mid-life and later life had an odds ratio of 7.67 (1.6 to 40.0) for Alzheimer’s disease compared with married or cohabiting people. The highest increased risk for Alzheimer’s disease was in carriers of the apolipoprotein E e4 allele who lost their partner before mid-life and were still widowed or divorced at follow-up. The progressive entering of several adjustment variables from mid-life did not alter these associations. Conclusions Living in a relationship with a partner might imply cognitive and social challenges that have a protective effect against cognitive impairment later in life, consistent with the brain reserve hypothesis. The specific increased risk for widowed and divorced people compared with single people indicates that other factors are needed to explain parts of the results. A sociogenetic disease model might explain the dramatic increase in risk of Alzheimer’s disease for widowed apolipoprotein E e4 carriers.

Brain-derived neurotrophic factor (BDNF) has a central role in brain plasticity by mediating changes in cortical thickness and synaptic density in response to physical activity and environmental enrichment. Previous studies suggest that physical exer

Aims: To examine the association between marital status and cognitive impairment among community-dwelling Chinese older adults. Methods: We analyzed data from 2,498 Chinese aged 55 and older from the Singapore Longitudinal Aging Study cohort. Cognitive impairment was defined as a Mini-Mental State Examination total score of 23 or below. Odds ratios of associations were reported and adjusted for potential confounders in logistic regression models. Results: The prevalence of cognitive impairment was 12.2% (n = 306). Being single was associated with about 2.5 times increased odds of cognitive impairment compared to being married (adjusted OR = 2.53, 95% CI: 1.41-4.55). The association between marital status and cognitive impairment was much stronger in men compared to that in women, and was indeed statistically significant only for men. Among the single and widowed persons social engagement was associated with a lower risk of cognitive impairment. Compared with subjects in the lowest tertile of social engagement scores, the odds of having cognitive impairment was lowered by 50% for subjects in the second and the third tertile. Conclusion: Being single or widowed was associated with higher odds of cognitive impairment compared to being married in a cohort of older Chinese men but not women.

To investigate the associations between midlife work-related stress and mild cognitive impairment (MCI), dementia, and Alzheimer’s disease later in life, in a large representative population. Cardiovascular Risk Factors, Aging and Dementia (CAIDE) study participants were randomly selected from independent population-based surveys (mean age 50 years). A random sample of 2,000 individuals was invited for two reexaminations including cognitive tests (at mean age 71 and mean age 78), and 1,511 subjects participated in at least one reexamination (mean follow-up 28.5 years). Work-related stress was measured using two questions on work demands that were administered in midlife. Analyses adjusted for important confounders. Higher levels of midlife work-related stress were associated with higher risk of MCI (odds ratio [OR], 1.38; 95% confidence interval [CI], 1.08–1.76), dementia (OR, 1.53; CI, 1.13–2.07), and Alzheimer’s disease (OR, 1.55; CI, 1.19–2.36) at the first follow-up among the CAIDE participants. Results remained significant after adjusting for several possible confounders. Work-related stress was not associated with MCI and dementia during the extended follow-up. Midlife work-related stress increases the risk for MCI, dementia, and Alzheimer’s disease in later life. The association was not seen after the extended follow-up possibly reflecting selective survival/participation, heterogeneity in dementia among the oldest old, and a critical time window for the effects of midlife stress.

Several studies have found depression and depressive feelings to be associated with subsequent dementia. As dementias typically have a long preclinical development phase, it has been difficult to determine whether depression and depressive feelings reflect a concurrent underlying dementia disease, rather than playing a causative role. Our aim was to investigate hopelessness, one dimension of depressive feelings, and evaluate the likelihood of a prodromal versus a causative role of hopelessness feelings in dementia development. We invited a random sample of 2000 survivors from a representative population in Eastern Finland, originally investigated in midlife between 1972 and 1987, for re-examination an average of 21 years later. The age of the 1449 persons who accepted the invitation was between 39 and 64 years (mean 50.4 years) in midlife and between 65 and 80 (mean 71.3) at follow-up. To measure feelings of hopelessness in midlife and at follow-up, the participants indicated their level of agreement to two statements about their own possible future. We used logistic regression to investigate the association between the combined scores from these two items and cognitive health at follow-up, while adjusting for several health and life-style variables from midlife and for apolipoprotein E4 (ApoE4) status, depression and hopelessness feelings at follow-up. We compared the associations with late-life cognitive health when feelings of hopelessness were either measured in midlife or at the follow-up. In addition we analyzed the changes in hopelessness scores from midlife to follow-up in participants who were either cognitively healthy or impaired at follow-up. We found higher levels of hopelessness in midlife, but not at follow-up, to be associated with cognitive impairment at follow-up; the adjusted odds ratio for each step of the five-level hopelessness scale was 1.30 (95% confidence interval 1.11–1.51) for any cognitive impairment and 1.37 (1.05–1.78) for Alzheimer’s disease. These associations remained significant also after the final adjustments for depressive feelings and for hopelessness at follow-up. The individual changes in hopelessness scores between midlife and follow-up were not systematically related to cognitive health at the follow-up. Our results suggest that feelings of hopelessness already in midlife may have long-term implications for cognitive health and increase the risk of Alzheimer’s disease in later life.