To examine sex differences in early stroke deaths according to cause of death.
We investigated 30-day deaths in patients with acute ischemic stroke enrolled in a multicenter stroke registry between 2007 and 2019 in Fukuoka, Japan. We estimated the multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of cause-specific deaths for women vs men using Cox proportional hazards models and competing risk models. The risk of acute infections during hospitalization and the associated case fatality rates were also compared between the sexes.
Among 17,956 patients with acute ischemic stroke (women: 41.3%), the crude 30-day death rate after stroke was higher in women than men. However, adjusting for age and stroke severity resulted in a lower risk of death among women (HR [95% CI]: 0.76 [0.62–0.92]). Analyses using competing risk models revealed that women were less likely to die of acute infections (subdistribution HR [95% CI]: 0.33 [0.20–0.54]). Further analyses showed that women were associated with a lower risk of acute infections during hospitalization (OR [95% CI]: 0.62 [0.52–0.74]) and a lower risk of death due to these infections (subdistribution HR [95% CI]: 052 [0.33–0.83]).
When adjusting for confounders, the female sex was associated with a lower risk of 30-day death after stroke, which could be explained by a female survival advantage in poststroke infections. Sex-specific strategies are needed to reduce early stroke deaths.
Classification of Evidence
This is a Class I prognostic study because it is a prospective population-based cohort with objective outcomes. Female sex appears to be protective against early stroke deaths and post stroke infections.