Effect of acetazolamide reactivity and long-term outcome in patients with major cerebral artery occlusive diseases

Abstract

Background and Purpose - It remains unclear whether hemodynamic insufficiency plays a major role in ischemic events. We performed a prospective follow-up study in ischemic stroke patients with occlusive large- artery diseases to determine whether stroke recurrence is related to reduced vasodilatory capacity, judged with single-photon emission CT and acetazolamide (ACZ) challenge. Methods - During the period from 1987 to 1995, we examined cerebral vasodilatory capacity with single-photon emission CT and an ACZ challenge in 105 consecutive stroke patients with severe stenosis (>75% in diameter) or occlusion of the internal carotid artery or the trunk of the middle cerebral artery who had no or minimal infarcts on CT. According to criteria reported earlier, the patients were divided into two groups: normal (negative ACZ, n=50) or reduced ACZ reactivity (positive ACZ, n = 55). They were prospectively followed at regular intervals for a median period of 2.7 years. Results - The Kaplan-Meier analysis revealed no difference in cumulative recurrence-free survival rate between the two groups. The multivariate analysis with Cox proportional hazards model demonstrated that a high systolic blood pressure at entry into the study significantly increased stroke recurrence (coefficient =.0466; hazard ratio=1.0477; 95% confidence interval=1.0017 to 1.0957; P=.04), whereas antihypertensive medication significantly reduced stroke recurrence (coefficient=-1.527; hazard ratio=0.217; 95% confidence interval=0.0612 to 0.771; P=.02), but no other variables including ACZ reactivity affected stroke recurrence rate. Conclusions - The present results demonstrate that reduced vasodilatory capacity does not play a major role in stroke recurrence. Antihypertensive therapy appears to reduce stroke recurrence even in patients with hemodynamically significant arterial diseases.