Importance: Clinical trials have generally shown a neutral effect of early blood pressure (BP) decreases on clinical outcomes after acute ischemic stroke. Whether the effect of early antihypertensive therapy differs for patients with ischemic stroke with or without prior hypertension is unclear.
Objective: To investigate the association between immediate antihypertensive treatment and patient outcomes according to the presence or absence of hypertension before stroke onset.
Design, setting, and participants: This study was a prespecified subgroup analysis of the China Antihypertensive Trial in Acute Ischemic Stroke (CATIS), a multicenter, single-blind, blinded end-points randomized clinical trial of 4071 patients with acute ischemic stroke and elevated systolic BP. Patients were recruited from August 2009 to May 2013, and this statistical analysis was performed using the intention-to-treat population from January to October 2018.
Interventions: Participants were randomly assigned to receive antihypertensive treatment (aimed at decreasing systolic BP by 10%-25% within the first 24 hours after randomization, achieving systolic BP <140 mm Hg and diastolic BP <90 mm Hg within 7 days, and maintaining this level during hospitalization) or to the control arm (discontinued all antihypertensive medications).
Main outcomes and measures: Primary outcome was a combination of death and major disability (modified Rankin Scale score ≥3; range 0-6, with higher values indicating greater disability) at 14 days or hospital discharge.
Results: In total, 2038 patients were randomized to receive antihypertensive treatment, and 2033 patients were randomized to the control group. The mean (SD) age was 62.0 (10.9) years, and 2604 participants (64.0%) were men. At day 14 or hospital discharge, the primary outcome was not different between the treatment and control groups among patients with or without prior hypertension (P = .97 for homogeneity): odds ratios (ORs) associated with treatment were 1.00 (95% CI, 0.87-1.16) for patients with prior hypertension and 1.00 (95% CI, 0.75-1.32) for patients without. Early antihypertensive treatment was associated with different rates of 3-month recurrent stroke (patients with hypertension: OR, 0.44; 95% CI, 0.25-0.77 vs without hypertension: OR, 3.43; 95% CI, 0.94-12.55; P = .005 for homogeneity) and vascular events (patients with hypertension: OR, 0.66; 95% CI, 0.43-1.02 vs those without hypertension: OR, 1.91; 95% CI, 0.75-4.83; P = .04 for homogeneity) by hypertension history.
Conclusions and relevance: Among patients with acute ischemic stroke, early antihypertensive treatment was not associated with different death and major disability outcomes by hypertension history. However, early antihypertension therapy was associated with a decreased rate of recurrent stroke among patients with a history of hypertension and may inform future studies in the optimal approach to hypertension management in the setting of acute ischemic stroke.
Trial registration: ClinicalTrials.gov identifier: NCT01840072.