Blood pressure variability on antihypertensive therapy in acute intracerebral hemorrhage: the Stroke Acute Management with Urgent Risk-factor Assessment and Improvement-intracerebral hemorrhage study

Background and purpose: The associations between early blood pressure (BP) variability and clinical outcomes in patients with intracerebral hemorrhage after antihypertensive therapy, recently clarified by a post hoc analysis of Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial 2 (INTERACT2), were confirmed using the Stroke Acute Management with Urgent Risk-factor Assessment and Improvement (SAMURAI)-intracerebral hemorrhage study cohort.

Methods: Patients with hyperacute (<3 hours from onset) intracerebral hemorrhage with initial systolic BP (SBP) >180 mm Hg were registered in a prospective, multicenter, observational study. All patients received antihypertensive therapy based on a predefined standardized protocol to lower and maintain SBP between 120 and 160 mm Hg using intravenous nicardipine. BPs were measured hourly during the initial 24 hours. BP variability was determined as SD and successive variation. The associations between BP variability and hematoma expansion (>33%), neurological deterioration within 72 hours, and unfavorable outcome (modified Rankin Scale, 4-6) at 3 months were assessed.

Results: Of the 205 patients, 33 (16%) showed hematoma expansion, 14 (7%) showed neurological deterioration, and 81 (39%) had unfavorable outcomes. The SD and successive variation of SBP were 13.8 (interquartile range, 11.5-16.8) and 14.9 (11.7-17.7) mm Hg, respectively, and those of diastolic BP were 9.4 (7.5-11.2) and 13.1 (11.2-15.9) mm Hg, respectively. On multivariate regression analyses, neurological deterioration was associated with the SD of SBP (odds ratio, 2.75; 95% confidence interval, 1.45-6.12 per quartile) and the successive variation of SBP (2.37; 1.32-4.83), and unfavorable outcome was associated with successive variation of SBP (1.42; 1.04-1.97). Hematoma expansion was not associated with any BP variability.

Conclusions: SBP variability during the initial 24 hours of acute intracerebral hemorrhage was independently associated with neurological deterioration and unfavorable outcomes. Stability of antihypertensive therapy may improve clinical outcomes.