Abstract MP86: Effects of Immediate Blood Pressure Reduction on Death and Major Disability in Acute Ischemic Stroke Patients by History of Hypertension and Use of Antihypertensive Medications

Abstract

Introduction: The effects of blood pressure (BP) reduction on clinical outcomes among acute stroke patient remain uncertain. Hypothesis: We tested the effects of immediate BP reduction on death and major disability at 14 days or hospital discharge and 3-month follow-up in acute ischemic stroke patients with and without a previous history of hypertension or use of antihypertensive medications. Methods: The China Antihypertensive Trial in Acute Ischemic Stroke (CATIS) randomly assigned patients with ischemic stroke within 48 hours of onset and elevated systolic BP (SBP) to receive antihypertensive treatment (N=2,038) or to discontinue all antihypertensive medications (N=2,033) during hospitalization. Randomization was stratified by participating hospitals and use of antihypertensive medications. Study outcomes were assessed at 14 days or hospital discharge and 3-month post-treatment follow-up. The primary outcome was death and major disability (modified Rankin Scale score≥3), and secondary outcomes included recurrent stroke and vascular events. Results: Mean SBP was reduced 12.7% in the treatment group and 7.2% in the control group within 24 hours after randomization (P<0.001). Mean SBP was 137.3 mmHg in the treatment group and 146.5 in the control group at day 7 after randomization (P<0.001). At 14 days or hospital discharge, the primary and secondary outcomes were not significantly different between the treatment and control groups by subgroups. At the 3-month follow-up, recurrent stroke was significantly reduced in the antihypertensive treatment group among patients with a history of hypertension (odds ratio 0.43, 95% CI 0.24-0.75, P=0.003) and among patients with a history of use of antihypertensive medications (odds ratio 0.41, 95% CI 0.20-0.84, P=0.01). All-cause mortality (odds ratio 2.84, 95% CI 1.11-7.27, P=0.03) was increased among patients without a history of hypertension. Conclusion: Immediate BP reduction lowers recurrent stroke among acute ischemic stroke patients with a previous history of hypertension or use of antihypertensive medications at 3 months. On the other hand, BP reduction increases all-cause mortality among patients without a history of hypertension.