Statin adherence after ischemic stroke or transient ischemic attack is associated with clinical outcome

Background: Statin therapy is beneficial for ischemic stroke patients, but little is known about whether statin adherence affects clinical outcome. We therefore evaluated the effect of statin adherence in patients with ischemic stroke or transient ischemic attack (TIA). Methods and Results: From Taiwan Bureau of National Health Insurance database, we enrolled patients with no prior statin therapy admitted for ischemic stroke or TIA between January 2002 and December 2005. Patients were grouped based on statin adherence according to medication possession ratio (MPR): good adherence (MPR >80%; n=2,274), intermittent adherence (MPR=40–80%; n=3,710), and poor adherence (MPR <40%; n=9,424). The study endpoint was the composite outcome of recurrent ischemic stroke, hemorrhagic stroke, and acute coronary event 1 year after statin initiation. Follow-up data were obtained through December 2010. During follow-up, composite endpoints occurred in 5,354 patients (34.7%): good adherence, 798 patients (35.1%); intermittent adherence, 1,338 patients (36.1%); and poor adherence, 3,218 patients (34.1%). Compared with the good adherence group, patients in the poor adherence group and intermittent adherence group had higher risk of worse clinical outcome (adjusted HR, 1.26 and 1.16, respectively; 95% CI: 1.17–1.37 and 1.07–1.27, respectively). Conclusions: Good statin adherence was associated with better clinical outcome in patients with acute ischemic stroke or TIA.