Comparative effects of intensive-blood pressure versus standard-blood pressure-lowering treatment in patients with severe ischemic stroke in the ENCHANTED trial.

OBJECTIVE

Limited data exist on the optimum level of SBP in thrombolyzed patients with acute ischemic stroke (AIS). We aimed to determine the effects of intensive blood pressure (BP) lowering, specifically in patients with severe AIS who participated in the international, Enhanced Control of Hypertension and Thrombolysis Stroke Study.

METHODS

Prespecificed subgroup analyzes of the BP arm of Enhanced Control of Hypertension and Thrombolysis Stroke Study, a multicenter, partial-factorial, open, blinded outcome assessed trial, in which 2227 thrombolysis-eligible and treated AIS patients with elevated SBP (>150 mmHg) were randomized to intensive (target 130-140 mmHg) or guideline-recommended (<180 mmHg) BP management. Severe stroke was defined by computed tomography or magnetic resonance angiogram confirmation of large-vessel occlusion, receipt of endovascular therapy, final diagnosis of large artery atheromatous disease, or high (>10) baseline neurological scores on the National Institutes of Health Stroke Scale. The primary efficacy outcome was death or any disability (modified Rankin scale scores 2-6). The key safety outcome was intracranial hemorrhage (ICH). Treatment effects estimated in logistic regression models are reported as odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

There were 1311 patients [mean age 67 years; 37% female; median baseline National Institutes of Health Stroke Scale of 11 (range 6.0-15.0)] with severe AIS. Overall, there was no significant difference in the primary outcome of death or disability. However, intensive BP lowering significantly increased mortality (OR 1.52, 95% CI 1.09-2.13; P = 0.014) compared with guideline BP lowering, despite significantly lowering clinician-reported ICH (OR 0.63, 95% CI 0.43-0.92; P = 0.016).

CONCLUSION

Intensive BP lowering is associated with increased mortality in patients with severe AIS despite lowering the risk of ICH. Further randomized trials are required to provide reliable evidence over the optimum SBP target in the most serious type of AIS.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01422616.