Findings from observational studies on the associations between vitamin E intake and stroke risk remain controversial, and the dose–response relationship between vitamin E intake and risk of stroke remains to be determined. We conducted a meta-analysis of prospective studies aiming to clarify the relationships between vitamin E intake and risk of stroke. Relevant studies were identified by searching online databases through to June 2018. We computed summary relative risks (RR) with corresponding 95 % CI. Among 3156 articles retrieved from online databases and relevant bibliographies, nine studies involving 3284 events and 220 371 participants were included in the final analyses. High dietary vitamin E intake was inversely associated with the risk of overall stroke (RR=0·83, 95 % CI 0·73, 0·94), and with the risk of stroke for individuals who were followed-up for <10 (RR=0·84, 95 % CI 0·72, 0·91). There was a non-linear association between dietary vitamin E intake and stroke risk (P=0·0249). Omission of any single study did not alter the summary result. In conclusion, this meta-analysis suggests that there is a significant inverse relationship between dietary vitamin E intake and stroke risk. This meta-analysis provides evidence that a higher dietary vitamin E intake is associated with a lower stroke risk.

Wide-ranging conceptual and diagnostic approaches to defining mild cognitive impairment (MCI) have led to highly variable prevalence and progression rates. We sought to examine whether bilateral hippocampal volumes and cerebrovascular risk factors in individuals characterized by two different neuropsychological definitions of MCI subtypes would also differ. Participants were 65 nondemented, community-dwelling, older adults, ages 62–91 years, drawn from a larger group of individuals enrolled in a longitudinal study of normal aging. A comprehensive neuropsychological definition of MCI that required the presence of more than one impaired score in a cognitive domain resulted in expected anatomical results; hippocampal volumes were significantly smaller in the aMCI group as compared to cognitively normal or nonamnestic MCI participants. However, a typical definitional scheme for classifying MCI based only on the presence of one impaired score within a cognitive domain did not result in hippocampal differences between groups. Global stroke risk factors did not differ between the two definitional schemes, although the relationship between stroke risk variables and neuropsychological performance did vary by diagnostic approach. The comprehensive approach demonstrated associations between stroke risk and cognition, whereas the typical approach did not. Use of more sophisticated clinical decision-making and diagnostic approaches that incorporate comprehensive neuropsychological assessment techniques is supported by this convergence of neuropsychological, neuropathological, and stroke risk findings. (JINS, 2009, 15, 890–897.)

Introduction:No epidemiological data exist concerning the influence of an earthquake on the risk of stroke. Whether the incidence of cerebrovascular stroke increased after the 1995 Hanshin-Awaji earthquake (EQ) in Japan and whether seismic intensity affected stroke risk dose-dependently was examined.

Methods:A retrospective cohort study was conducted among residents, who were living in two towns on the island of Awaji and were participants of the National Health Insurance (NHI) program. The two towns were divided into 11 districts and their respective damage and socioeconomic states were investigated. Reviewing the NHI documents issued before and after the EQ, people who had strokes (9th International Classification of Diseases, codes 430–431 or 433–434.9) were identified. Risk of stroke in relation to the seismic intensities, was assessed with the Cox proportional hazard model.

Results:Among subjects aged 40 to 99 years, 45 of 8,758 (0.514%) had a stroke the year before the EQ, 72 of 8,893 (0.810%) had a stroke in the first year following the EQ, and 49 of 8,710 (0.566%) had a stroke in the second year following the EQ. In districts where the earthquake's intensity was ≤9.5 on the modified Mercalli intensity (MMI), compared with the year prior to the EQ, the relative risk (RR) of stroke was 2.4 (95% confidence interval (CI) 1.1, 5.0) in the first year following the EQ, after adjusting for age, gender, and income. In that year, compared with MMI of <8.5–9.0, RRs for 9.0–9.5 and ≥9.5 were 1.6 (CI 0.9, 2.1) and 2.0 (CI 1.1, 3.7), respectively (p for trend 0.02). No trend for the RR was observed in the year before the EQ or in the second year following the EQ.

Conclusion Stroke increased in the first year following the EQ. The increase was associated with seismic intensity in a dose-response manner. Results suggest a potential threshold for RR of >2.0 in areas near 9.5 on the MMI scale.