Background: Intensive blood pressure (BP) reduction is recommended after intracerebral hemorrhage (ICH); however, treatment effects were modest across trials. Untreated chronic hypertension (HTN) impairs cerebral autoregulation, and cerebral hypoperfusion may limit the benefit of intensive BP reduction in the setting of impaired autoregulation. We hypothesized that untreated HTN treatment reduced the benefit of BP reduction on early neurologic decline (END). Methods: This secondary analysis of the Antihypertensive Treatment of Acute Cerebral Hemorrhage-2 trial included patients with a history of HTN and BP medication adherence within 30 days prior to ICH. Patients were randomized to a standard (<180 mmHg) or intensive (<140 mmHg) BP target, and highest Glasgow coma scale (GCS) was recorded hourly over the first 24 hours. Patients receiving sedation were excluded. The primary outcome was the mean change in GCS relative to baseline (deltaGCS). Multivariable mixed-effects regression modelled the association between repeated measures of deltaGCS over 24 hours with BP target, HTN treatment and their interaction with adjustment for demographics, ICH severity, initial BP, and hematoma expansion. Results: From 694 patients, 280 had treated and 414 had untreated HTN. Patients with untreated HTN were younger (59.0 vs 66.8 years) with more males (65.7% vs 55.0%), higher initial systolic BP (204.9 mmHg vs 194.2 mmHg) , less cardiovascular comorbidities, and more non-lobar ICH (92.3% vs 83.6%). Baseline GCS, ICH volume, and assigned BP targets were similar (Table 1). In the primary analysis, intensive BP reduction was associated with 0.30 points (95% CI 0.02, 0.58; p=0.034) higher GCS compared to standard BP reduction, and the benefit was limited to patients with treated HTN (interaction: p=0.046) (Table 2, Figure 1). The association was similar in sensitivity analyses accounting for alternative definitions of END, BP reduction speed, and undiagnosed HTN. Conclusion: In this post-hoc subgroup analysis of ATACH-2, we found chronic HTN treatment modified the effect of intensive BP reduction on END. Further development of personalized BP targets should be explored.
Ridha et al. (Thu,) studied this question.