The outcomes of statin therapy in patients with acute ischemic stroke in Taiwan: a nationwide epidemiologic study

Abstract

Summary Background Acute stroke is the third leading cause of death in Taiwan. Although statin therapy is widely recommended for stroke prevention, little is known about the epidemiology of statin therapy after acute ischemic stroke (AIS) in Taiwan. To investigate the effects of statin therapy on recurrent stroke, intracranial hemorrhage (ICH), coronary artery disease (CAD), cost of hospitalization and mortality, we conducted a nationwide population-based epidemiologic study. Methods Cases of AIS were identified from the annual hospitalization discharge diagnoses of the National Health Insurance Research Database with the corresponding International Classification of Diseases, ninth revision codes from January 2001 to December 2010. We divided the AIS patients into three groups: non-statin, pre-stroke statin and post-stroke statin. Results A total of 422 671 patients with AIS (including 365 419 cases in the non-statin group, 22 716 cases in the pre-stroke statin group and 34 536 cases in the post-stroke statin group) were identified. When compared to the non-statin group, both statin groups had a lower recurrent stroke risk [pre-stroke statin: odds ratio (OR) = 0.84; 95% confidence interval (CI) = 0.82–0.87; P < 0.0001; post-stroke statin: OR = 0.89; 95% CI = 0.86–0.91; P < 0.0001], lower ICH risk (pre-statin: OR = 0.75; 95% CI = 0.69–0.82; P < 0.0001; post-stroke statin: OR = 0.75; 95% CI = 0.71–0.81; P < 0.0001), and a lower mortality rate (pre-stroke statin: OR = 0.56; 95% CI = 0.53–0.59; P < 0.0001; post-stroke statin: OR = 0.51; 95% CI = 0.48–0.53; P < 0.0001). In terms of CAD, only the post-statin group had a lower risk (OR = 0.81; 95% CI = 0.79–0.84; P < 0.0001) than the non-statin group. The post-statin group had the lowest 1-year medical costs after index discharge among the three groups. Conclusions Statin therapy reduced the risks of recurrent stroke, CAD, ICH and the first year mortality in patients after AIS. Treatment with statin therapy after AIS is a cost-effective strategy in Taiwan.