Intensive versus guideline-recommended blood pressure reduction in acute lacunar stroke with intravenous thrombolysis therapy: the ENCHANTED trial

Background and purpose: This was an investigation of the differential effects of early intensive versus guideline-recommended blood pressure (BP) lowering between lacunar and non-lacunar acute ischaemic stroke (AIS) in the BP arm of the Enhanced Control of Hypertension and Thrombolysis Stroke Study (ENCHANTED). Methods: In 1,632 participants classified as having definite or probable lacunar (n = 454 [27.8%]) or non-lacunar AIS according to pre-specified definitions based upon clinical and adjudicated imaging findings, mean BP changes over days 0–7 were plotted, and systolic BP differences by treatment between subgroups were estimated in generalized linear models. Logistic regression models were used to estimate the BP treatment effects on 90-day outcomes (primary, an ordinal shift of modified Rankin scale scores) across lacunar and non-lacunar AIS after adjustment for baseline covariables. Results: Most baseline characteristics, acute BP and other management differed between lacunar and non-lacunar AIS, but mean systolic BP differences by treatment were comparable at each time point (all p_interaction > 0.12) and over 24 h post-randomization (−5.5, 95% CI −6.5, −4.4 mmHg in lacunar AIS vs. −5.6, 95% CI −6.3, −4.8 mmHg in non-lacunar AIS, p_interaction = 0.93). The neutral effect of intensive BP lowering on functional outcome and the beneficial effect on intracranial haemorrhage were similar for the two subgroups (all p_interaction > 0.19). Conclusions: There were no differences in the treatment effect of early intensive versus guideline-recommended BP lowering across lacunar and non-lacunar AIS.