Association of Hemispheric Laterality With Neurosurgical Intervention in Intracerebral Hemorrhage: A Posthoc Bayesian Analysis of ATACH-2 and ERICH

BACKGROUND: Hemispheric laterality influences clinical management in stroke. Given the increasing enthusiasm for surgical management of intracerebral hemorrhage (ICH), we evaluated the association of hemispheric laterality with the likelihood of receiving neurosurgical intervention and subsequent 90-day functional outcomes. METHODS: This post hoc analysis included 3477 patients with supratentorial ICH from 2 prospective studies: the ATACH-2 trial (Antihypertensive Treatment of Acute Cerebral Hemorrhage II), conducted at 110 sites in the United States, Japan, China, Taiwan, South Korea, and Germany (2011–2015), and the ERICH study (Ethnic/Racial Variations of Intracerebral Hemorrhage), conducted across 19 centers in the United States (2010–2015). The primary outcome was neurosurgical intervention (hematoma evacuation, decompressive craniectomy, or other craniotomy). Secondary outcomes included external ventricular drain placement, 90-day modified Rankin Scale score, and EuroQOL domains. Hierarchical Bayesian regression models estimating the association between ICH laterality and outcomes were adjusted for age, admission Glasgow Coma Scale, ICH location, ICH volume, and intraventricular hemorrhage. RESULTS: Of 3477 patients, right hemispheric ICH was associated with a higher likelihood of receiving neurosurgical intervention (adjusted odds ratio, 1.65 [95% credible interval, 1.28–2.14]) and external ventricular drain placement (adjusted odds ratio, 1.22 [95% credible interval, 1.04–1.44]) compared with left hemispheric ICH. This association was directionally consistent across ICH locations, study cohorts, and prior specifications. Despite the lower rates of surgical intervention in left hemispheric ICH, there was no meaningful difference in 90-day functional outcomes in patients with left and right hemispheric ICH. CONCLUSIONS: Right hemispheric ICH is associated with a higher likelihood of neurosurgical intervention compared with left hemispheric ICH, though 90-day functional outcomes remain similar between groups. Although these findings highlight a potential laterality-associated variation in neurosurgical intervention, residual confounding from unmeasured anatomic severity and family preferences cannot be excluded. Prospective studies are needed to delineate the explicit clinical and prognostic drivers of surgical decision-making to optimize treatment allocation in ICH. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01176565 and NCT01202864.