Systolic Blood Pressure Trajectory and Outcomes in Acute Intracerebral Hemorrhage: Pooled Analysis of the 4 INTERACT and ATACH-II Clinical Trials

Clinical Snapshot

Key Findings

• P Value: p = 0.04 for trend across groups

• Effect Size: Progressive increase in odds of poor outcome across trajectory groups

• Primary Outcome: Poor functional outcome (mRS 3-6) at 90 days

• Nnt Or Sensitivity: High-to-moderate trajectory group showed 90% increased odds of poor outcome compared to low trajectory group

• Confidence Interval: Adjusted OR for severe hypertensive group: 1.90 (95% CI 1.32-2.73)

Clinical Application

Requires continuous BP monitoring and trajectory assessment over 24 hours, feasible in stroke units and intensive care settings Relevant to Australian stroke units following National Stroke Foundation guidelines. Supports individualized BP management strategies rather than uniform targets. May inform TGA-approved antihypertensive protocols in acute stroke care. Adults presenting with acute intracerebral hemorrhage requiring blood pressure management

Abstract

BACKGROUND AND OBJECTIVES: While moderate and rapid systolic blood pressure (SBP) lowering was associated with better functional outcomes after intracerebral hemorrhage (ICH), large reductions in SBP within 1 hour, for example, reductions from >200 to <140 mm Hg, diminished or even reversed these beneficial effects. We aimed to define the optimal trajectory of SBP control in relation to favorable functional outcomes after acute ICH. METHODS: We conducted a pooled analysis of individual patient-level data from all 4 Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT) and second Antihypertensive Treatment of Acute Cerebral Hemorrhage (ATACH-II) trials, which were international, randomized, open-label, blinded, end point-assessed, controlled trials that determined the effectiveness of early intensive SBP control in acute ICH. Latent class analysis grouped SBP trajectories over the first 24 hours (9 measurements) into defined clusters. The primary outcome was functional recovery at 90 days after randomization, defined as modified Rankin Scale (mRS) scores of 3-6. Logistic regression models with adjustment for baseline covariates and trial were used to determine associations between SBP cluster trajectories and outcomes in INTERACT, with validation in ATACH-II. RESULTS: A total of 11,269 patients (INTERACT n = 10,269; ATACH-II n = 1,000; mean age 62.4 years; female 36.4%) with at least 1 postrandomization SBP reading were included. Six SBP trajectories were identified: low, moderate-to-low, moderate, high, high-to-moderate, and high-to-low. Compared with the low SBP group, associations with poor functional outcome (mRS scores 3-6) increased progressively across other groups in INTERACT (p = 0.04 for trend). Adjusted odds ratios (95% CI) for groups 2 to 6 were 1.16 (0.98-1.37), 1.44 (1.18-1.75), 1.46 (1.15-1.87), 1.90 (1.32-2.73), and 1.28 (1.02-1.60), respectively. A similar albeit nonsignificant trend was observed in ATACH-II due to limited power. DISCUSSION: Distinct SBP trajectories over 24 hours defined prognosis after ICH, with a severe hypertensive group having the highest odds of death or disability, regardless of the BP-lowering strategy used. These findings highlight the importance of well-controlled but tailored SBP management strategies after ICH. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that distinct SBP trajectories over 24 hours are associated with prognosis after acute ICH, with a severe hypertensive group having the highest odds of poor functional outcome, regardless of the BP-lowering strategy used. TRIAL REGISTRATION INFORMATION: (INTERACT1 NCT00226096; INTERACT2 NCT00716079; INTERACT3 NCT03209258; INTERACT4 NCT03790800; ATACH-2 NCT01176565).

References

1. 1.Wang, X., Phan, T. G., Ren, X., Ma, H. H., Li, Q., Ouyang, M., Delcourt, C., Chen, X., Wang, J., Robinson, T. G., Arima, H., Ma, L., Hu, X., You, C., Liu, L., Venturelli, P. M., Martins, S. C., Pontes-Neto, O. M., Chalmers, J. P., Song, L., Qureshi, A. I., & Anderson, C. (2026). Systolic Blood Pressure Trajectory and Outcomes in Acute Intracerebral Hemorrhage: Pooled Analysis of the 4 INTERACT and ATACH-II Clinical Trials. Neurology. https://doi.org/10.1136/bmj.d5888