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.

Keywords: drug therapy; mild cognitive impairment; prevention & control; stroke; vascular dementia.