Sex Differences in the Incidence of Hemorrhagic and Ischemic Stroke among Diabetics in Taiwan

Background: Diabetes mellitus is an important risk factor for stroke, but whether there is differential gender-specific risk has not been fully elucidated. We aimed to explore the impact of gender on incidence and relative risks of hemorrhagic and ischemic stroke among the diabetic population in Taiwan. Methods: In this study, 500,868 diabetic patients and 500,248 age matched and-sex-matched nondiabetic individuals were linked to inpatient claims (1997-2002) to identify hospitalizations for nontraumatic hemorrhagic and ischemic stroke. Incidence density was calculated with the Poisson assumption, and Kaplan-Meier analysis was used to assess the cumulative incidence over a 6-year follow-up period. We also evaluated the relative hazards of stroke in relation to diabetes with the Cox proportional hazard model, adjusted with demographics and geographic regions. Results: The incidence of hemorrhagic stroke in diabetic women was less than that in diabetic men except in those aged >= 85, but the difference between male and female diabetic patients was less pronounced with ischemic stroke. The hazard ratios (HRs) of hemorrhagic and ischemic stroke among diabetic women were increased by a magnitude of 1.2 and 1.32, respectively, which were significantly higher than those of diabetic men. Further age-stratified analysis indicated that young and middle-aged diabetic women tended to have higher HRs and that diabetic women aged < 35 suffered from particularly high HRs (HR 7.69, 95% confidence interval [CI] 1.81-32.75 for hemorrhagic stroke, and HR 8.46, 95% CI 4.28-16.75 for ischemic stroke). Conclusions: There was a significant gender-diabetes interactive effect on the incidence of hemorrhagic and ischemic stroke. Additionally, young Taiwanese diabetic patients were most vulnerable to an increased relative risk of hemorrhagic and ischemic stroke. Comprehensive diabetic care with stroke prevention measures should be emphasized in young diabetic people in order to prevent premature disability.