Antihypertensive therapy in atherothrombotic stroke survivors with or without reduced acetazolamide reactivity. A long-term prospective study

It remains controversial how to manage hypertension in stroke survivors. Some studies have indicated that antihypertensive therapy can effectively reduce stroke recurrence. Based on other observations, however, even a mild reduction of systemic blood pressure brought about TIA or ischemic stroke in patients with a reduced vasodilatory capacity in the brain. Employing single photon emission computed tomography (SPECT) with acetazolamide (ACZ) challenge, we examined 107 consecutive patients with severe stenosis (≥75% in diameter) or occlusion of the internal carotid artery or middle cerebral artery. who demonstrated no or minimal hypodensity on CT. The patients were divided into two groups: normal (negative ACZ, n=50) or reduced ACZ reactivity (positive ACZ, n=57), according to the criteria reported earlier. They were examined prospectively at regular intervals for 2.7 years. Stroke recurred in 15 patients: 6 with normal and 9 with reduced ACZ reactivities. Multivariate analysis with a Cox's proportional hazards model demonstrated that antihypertensive therapy significantly reduced stroke recurrence (coefficient=0.21, hazard ratio=0.071, 95% CI: 0.007 to 0.689, p=0.02). However, no other variables, including the ACZ reactivity. affected the stroke recurrence rate. Three of 4 patients with probable hemodynamic recurrence had a reduced ACZ reactivity at entry. Stroke recurred ipsilaterally to the arterial stenosis/occlusion in patients with positive ACZ who were given antihypertensive medication. The present findings indicate that antihypertensive therapy can effectively stroke reduce recurrence, particularly in patients with a normal ACZ reactivity. However, antihypertensive medication may have a danger of inducing ''hemodynamic'' stroke recurrence in some patients with a reduced ACZ reactivity. (author)