Background: There is no specific recommendation on statin therapy for cardioembolic stroke (CES) patients in current stroke guidelines. We evaluated the effect of statin on major vascular events following acute ischemic stroke in patients with CES and no other indications for statin.
Methods: Using a prospective multicenter stroke registry database, we identified acute ischemic stroke patients who were hospitalized between 2008 and 2015 and were categorized into CES according to the Trial of Org 10172 in Acute Stroke Treatment classification. Patients who had established indications for statin in accordance with the recent stroke guidelines were excluded. Primary outcome measure was a major vascular event, a composite of stroke recurrence, myocardial infarction and vascular death; and secondary outcome measures were stroke recurrence and all-cause death. We performed frailty model analysis to estimate hazard ratios (HRs) of statin therapy on outcomes accounting for variation in quality of care among centers. Stabilized inverse probability of treatment weighting method with propensity scores was used to remove baseline imbalances between statin users and non-users.
Results: Of the 6124 CES patients, 2987 patients (male, 52%; mean age, 73±12 years) met the eligibility criteria; and 2125 (71%) of 2987 patients were on statin at discharge. Compared to the non-users, the statin users were more likely to arrive at hospitals later, have milder neurologic deficits at presentation, be on stain prior to index stroke and have hyperlipidemia and were less likely to have atrial fibrillation and occlusion of relevant cerebral arteries. During the median follow-up of 364 days, major vascular events were observed in 118 patients (5.6%) among the statin users and 177 patients (20.5%) among the non-users, respectively (p<0.001 on log rank test); the adjusted HR of statin therapy was 0.35 (95% confidence interval, 0.27-0.46). The adjusted HRs of statin therapy were 0.71 (0.49-1.04) for stroke recurrence and 0.55 (0.46-0.66) for all-cause death, respectively.
Conclusion: This study suggests that statin therapy may reduce major vascular events and all-cause death in cardioembolic stroke patients without definite indications for statin.