No abstract

Women are reported to have greater mortality in the short term after stroke than men. In a review of 31 populationbased studies of short-term mortality after stroke, Appelros et al 1 reported that women had a 25% greater risk of 1-month crude mortality than men. It remains unclear what accounts for this disparity and whether these differences persist into the Background-Women are reported to have greater mortality after stroke than men, but the reasons are uncertain. We examined sex differences in mortality at 1 and 5 years after stroke and identified factors contributing to these differences. Methods and Results-Individual participant data for incident strokes were obtained from 13 population-based incidence studies conducted in Europe, Australasia, South America, and the Caribbean between 1987 and 2013. Data on sociodemographics, stroke-related factors, prestroke health, and 1-and 5-year survival were obtained. Poisson modeling was used to estimate the mortality rate ratio (MRR) for women compared with men at 1 year (13 studies) and 5 years (8 studies) after stroke. Studyspecific adjusted MRRs were pooled to create a summary estimate using random-effects meta-analysis. Overall, 16 957 participants with first-ever stroke followed up at 1 year and 13 216 followed up to 5 years were included. Crude pooled mortality was greater for women than men at 1 year (MRR 1.35; 95% confidence interval, 1.24-1.47) and 5 years (MRR 1.24; 95% confidence interval, 1.12-1.38). However, these pooled sex differences were reversed after adjustment for confounding factors (1 year MRR, 0.81; 95% confidence interval, 0.72-0.92 and 5-year MRR, 0.76; 95% confidence interval, 0.65-0.89).Confounding factors included age, prestroke functional limitations, stroke severity, and history of atrial fibrillation. Conclusions-Greater mortality in women is mostly because of age but also stroke severity, atrial fibrillation, and prestroke functional limitations. Lower survival after stroke among the elderly is inevitable, but there may be opportunities for intervention, including better access to evidence-based care for cardiovascular and general health. There have been no studies specifically designed to examine sex differences in long-term mortality after stroke. Identifying factors that explain the sex differences in mortality is important because better understanding could lead to interventions to reduce the disparities.2 In an Australian study, the 36% greater risk of death at 28 days for women compared with men was explained by age, prestroke health, stroke severity, and use of anticoagulants at discharge. 3 After adjustment in that study, women had a 17% lower short-term mortality than men. It is unknown whether these same factors account for the relative sex differences in other geographical regions or in long-term mortality.Our aims were to quantify the relative sex difference in long-term mortality and to identify factors that contribute to the greater mortality of women after stroke using a meta-analysis of pooled individual participant...