Ten-year trends in sex differences in cardiovascular risk factors, in-hospital management, and outcomes of ischemic stroke in China: Analyses of a nationwide serial cross-sectional survey from 2005 to 2015

Abstract

Background: Women with stroke differ from men in terms of risk factors, treatment, and outcomes. However, previous inconsistent results in China hampered the development of tailored sex-specific strategies for ischemic stroke management. We performed a nationwide serial cross-sectional survey to obtain national-level estimates to assess the 10-year trends in sex differences in cardiovascular risk factors, in-hospital management, and outcomes in China from 2005 to 2015. Methods: We used a two-stage random sampling design, economic-geographical region-stratified random sampling for hospitals first and then systematic sampling for patients, to obtain a nationally representative sample of ischemic strokes in China in 2005, 2010, and 2015. We extracted data on clinical characteristics, management measures (diagnostic tests, interventions, and secondary prevention treatments), in-hospital outcomes (all-cause in-hospital mortality, discharge against medical advice [DAMA], and a composite outcome of in-hospital death and DAMA), and comorbidities. We applied weights proportional to the inverse sampling fraction of hospitals within each stratum and the inverse sampling fraction of patients within each hospital. Results: A total of 26,900 ischemic stroke admissions were analyzed. Compared to men, women had a much lower prevalence of current smokers and a slightly higher prevalence of hypertension, diabetes, dyslipidemia, and atrial fibrillation at admission. Prevalence differences between sex in these cardiovascular risk factors were stable except for atrial fibrillation (decreased from 3.7% [95% CI: 1.8% to 5.7%] to 1.3% [95% CI: 0.5% to 2.0%]) and current smoker (increased from −18.0 [95% CI: –20.2% to –15.9%] to –25.6% [95% CI: –26.6% to –24.6%]). From 2005 to 2015, in-hospital management and outcomes were improved both for women and men, and sex differences in cerebrovascular assessment, cervical vessels assessment, and transthoracic echocardiography/transesophageal echocardiography were improved as well. However, women increased more slowly than men in the administration of clopidogrel (from 0.3% [95% CI: −0.9% to 1.4%) to −7.3% [95% CI: −8.7% to −6.0%]) and aspirin plus clopidogrel (0.3% [95% CI: −5.0% to 1.1%] to −5.0% [95% CI: −6.2% to −3.9%]). Conclusion: Compared to men, women patients with ischemic stroke had a steadily higher prevalence of cardiovascular risk factors, a slower increase rate in the administration of key secondary prevention drugs, and comparable in-hospital outcomes. More effort should be paid to the treatment and control of cardiovascular risk factors and also to the prescription of antiplatelets at discharge for women.