Objectives To estimate 10 year decline in cognitive function from longitudinal data in a middle aged cohort and to examine whether age cohorts can be compared with cross sectional data to infer the effect of age on cognitive decline.Design Prospective cohort study. At study inception in 1985-8, there were 10 308 participants, representing a recruitment rate of 73%.Setting Civil service departments in London, United Kingdom.Participants 5198 men and 2192 women, aged 45-70 at the beginning of cognitive testing in 1997-9.Main outcome measure Tests of memory, reasoning, vocabulary, and phonemic and semantic fluency, assessed three times over 10 years.Results All cognitive scores, except vocabulary, declined in all five age categories (age 45-49, 50-54, 55-59, 60-64, and 65-70 at baseline), with evidence of faster decline in older people. In men, the 10 year decline, shown as change/range of test×100, in reasoning was −3.6% (95% confidence interval −4.1% to −3.0%) in those aged 45-49 at baseline and −9.6% (−10.6% to −8.6%) in those aged 65-70. In women, the corresponding decline was −3.6% (−4.6% to −2.7%) and −7.4% (−9.1% to −5.7%). Comparisons of longitudinal and cross sectional effects of age suggest that the latter overestimate decline in women because of cohort differences in education. For example, in women aged 45-49 the longitudinal analysis showed reasoning to have declined by −3.6% (−4.5% to −2.8%) but the cross sectional effects suggested a decline of −11.4% (−14.0% to −8.9%). ConclusionsCognitive decline is already evident in middle age (age 45-49).

Objective To evaluate the association between migraine and cognitive decline among women.Design Prospective cohort study. Setting Women's Health Study, United States.Participants 6349 women aged 65 or older enrolled in the Women's Health Study who provided information about migraine status at baseline and participated in cognitive testing during follow-up. Participants were classified into four groups: no history of migraine, migraine with aura, migraine without aura, and past history of migraine (reports of migraine history but no migraine in the year prior to baseline). Main outcome measuresCognitive testing was carried out at two year intervals up to three times using the telephone interview for cognitive status, immediate and delayed recall trials of the east Boston memory test, delayed recall trial of the telephone interview for cognitive status 10 word list, and a category fluency test. All tests were combined into a global cognitive score, and tests assessing verbal memory were combined to create a verbal memory score. ResultsOf the 6349 women, 853 (13.4%) reported any migraine; of these, 195 (22.9%) reported migraine with aura, 248 (29.1%) migraine without aura, and 410 (48.1%) a past history of migraine. Compared with women with no history of migraine, those who experienced migraine with or without aura or had a past history of migraine did not have significantly different rates of cognitive decline in any of the cognitive scores: values for the rate of change of the global cognitive score between baseline and the last observation ranged from −0.01 (SE 0.04) for past history of migraine to 0.08 (SE 0.04) for migraine with aura when compared with women without any history of migraine. Women who experienced migraine were also not at increased risk of substantial cognitive decline (worst 10% of the distribution of decline). When compared with women without a history of migraine, the relative risks for the global score ranged from 0.77 (95% confidence interval 0.46 to 1.28) for women with migraine without aura to 1.17 (0.84 to 1.63) for women with a past history of migraine. ConclusionIn this prospective cohort of women, migraine status was not associated with faster rates of cognitive decline.

Rationale Higher social integration is associated with lower cardiovascular mortality; however, whether it is associated with incident coronary heart disease (CHD), especially in women, and if associations differ by case fatality is unclear. Objectives This study sought to examine the associations between social integration and risk of incident CHD in a large female prospective cohort. Methods and Results 76,362 women in the Nurses’ Health Study (NHS), free of CHD and stroke at baseline (1992), were followed until 2014. Social integration was assessed by a simplified Berkman-Syme Social Network Index every 4 years. Endpoints included nonfatal myocardial infarction (MI) and fatal CHD. 2,372 incident CHD events occurred throughout follow-up. Adjusting for demographic, health/medical risk factors and depressive symptoms, being socially integrated was significantly associated with lower CHD risk, particularly fatal CHD. The most socially integrated women had a hazard ratio of 0.55 (95% confidence interval, 0.41–0.73) of developing fatal CHD compared to those least socially integrated (p-for-trend < 0.0001). When additionally adjusting for lifestyle behaviors, findings for fatal CHD were maintained but attenuated (p-for-trend = 0.02) whereas the significant associations no longer remained for nonfatal MI. The inverse associations between social integration and nonfatal MI risk were largely explained by health-promoting behaviors, particularly through differences in cigarette smoking; however, the association with fatal CHD risk remained after accounting for these behaviors and thus may involve more direct biological mechanisms. Conclusions Social integration is inversely associated with CHD incidence in women, but is largely explained by lifestyle/behavioral pathways.