Long-Term Effects of Secondary Prevention on Cognitive Function in Stroke Patients

Abstract

Background— Limited long-term follow-up data exist on the impact of appropriate secondary prevention therapies on cognitive function in patients after first-ever stroke. The aim of this study is to determine the effect of secondary prevention of vascular events on cognitive function after stroke. Methods and Results— Data were collected between 1995 and 2011 (n=4413) from the community-based South London Stroke Register covering an inner-city multiethnic source population of 271 817 inhabitants. Modified Poisson regression models were constructed to adjust for cognitive function status at 3 months, demographic and socioeconomic characteristics, case mix, stroke subtype, vascular risk factors, disability, and stroke recurrence. In patients with ischemic strokes without a history of atrial fibrillation (AF), there was a reduced risk of cognitive impairment associated with the use of different prevention treatments: (1) antihypertensives (relative risk, 0.7 [95% confidence interval, 0.57–0.82] for diuretics; relative risk, 0.8 [95% confidence interval, 0.64–0.98] for angiotensin-converting enzyme inhibitors; and relative risk, 0.7 [95% confidence interval, 0.55–0.81] for their combination), (2) a combination of aspirin and dipyridamole (relative risk, 0.8 [95% confidence interval, 0.68–1.01]), and (3) statin (relative risk, 0.9 [95% confidence interval, 0.76–1.06]) when clinically indicated. Protective effects against cognitive impairment were also observed in patients on the combination of antihypertensives, antithrombotic agents, and lipid-lowering drugs (relative risk, 0.55 [95% confidence interval, 0.40–0.77]). No significant associations were noted between poststroke cognitive impairment and antihypertensives among hemorrhagic stroke patients. Conclusions— Appropriate vascular risk management was associated with a long-term reduced risk of cognitive impairment. Focus on optimal preventive drug therapy of vascular risk factors and management should be supported.