Utilization of statins beyond the initial period after stroke and 1-year risk of recurrent stroke

Background--In-hospital discontinuation of statins has been linked to poorer early stroke outcomes, but the consequences of postdischarge discontinuation or dose reduction of statin treatment are unknown. The objective of this study was to explore the effects of statin discontinuation or statin dose reduction on recurrent stroke risk. Methods and Results--We conducted a nationwide cohort study using the data from the Taiwan National Health Insurance Research Database. Our source population comprised all patients who were prescribed a statin within 90 days of discharge after an ischemic stroke between 2001 and 2012. Patients were categorized into 3 groups: statin-discontinued, statin-reduced, and statin-maintained. Cox proportional hazard models were used to estimate the hazard ratios and 95%CIs of recurrent stroke during 1-year follow-up in the groups who discontinued statins or reduced statin dose compared with the group who maintained statins as the reference. Among the 45 151 ischemic stroke patients meeting criteria, during the day-90 to day-180 period, 7.0% were on reduced statin therapy, and 18.5% were not on any statin therapy. Compared with maintained-statin intensity therapy, discontinuation of statins was associated with an increased hazard of recurrent stroke (adjusted hazard ratio 1.42, 95%CI 1.28-1.57), whereas reduced-statin dose was not associated with an additional risk (adjusted hazard ratio 0.94, 95%CI 0.78-1.12). Propensity-matching analysis obtained similar results. Conclusions--Discontinuation of statin therapy between 3 and 6 months after an index ischemic stroke was associated with a higher risk of recurrent stroke within 1 year after statin discontinuation.