Cerebral microbleeds (CMBs), or small cerebral hemorrhages at the level of capillaries and arterioles, are not associated with greater hematoma expansion, death, or disability at 3 months in patients with intracerebral hemorrhage (ICH) compared with patients with ICH without CMBs, as reported in a study published in JAMA Neurology. In addition, CMBs do not significantly affect response to intensive blood pressure (BP) lowering therapy in these patients.
Investigators performed a preplanned secondary analysis of the open-label, randomized Antihypertensive Treatment of Acute Cerebral Hemorrhage 2 (ATACH-2) study, specifically on the magnetic resonance images obtained during the intensive BP lowering portion of the trial. In this trial, a total of 1000 eligible participants with ICH volumes <60 mL and a Glasgow Coma Scale score ≥5 at baseline were randomly assigned (1:1) to a systolic BP target of 110 to 139 mm Hg (intensive treatment) vs a BP target of 140 to 179 mm Hg (standard treatment) with intravenous nicardipine hydrochloride.
A total of 167 participants with CMBs (n = 120) and no CMBs (n = 47) were included in this secondary analysis. Death or disability at 3 months comprised the primary outcome, whereas the secondary outcome included a ≥33% expansion in hematoma volume, as assessed by a computed tomography scan.
The primary outcome of death or disability (modified Rankin Scale score ≥4) was observed in 46 (29.3%) of 157 patients during the mean follow-up of 92.3 days. The same proportion of patients with CMBs and without CMBs experienced the primary outcome during follow-up (29.3% vs 29.3%, respectively). An analysis that adjusted for treatment group, baseline Glasgow Coma Scale score, age, and other covariates found that patients with CMBs did not have an increased risk for death or disability (adjusted relative risk [aRR], 0.83; 95% CI, 0.40-1.71; P =.61). In addition, patients with CMBs did not demonstrate a significantly lower risk for hematoma volume expansion (RR, 1.00; 95% CI, 0.42-2.39; P =.99).
The risk for the primary outcome was also similar among participants with CMBs who were randomly assigned to intensive vs standard acute BP lowering therapy (crude RR, 1.19; 95% CI, 0.61-2.33; P =.61), with no significant difference observed among non-CMB patients (crude RR, 1.42; 95% CI, 0.43-4.70; P =.57). Hematoma volume expansion rates were also similar among CMB (crude RR, 0.54; 95% CI, 0.22-1.34; P =.18) and non-CMB (crude RR, 1.00; 95% CI, 0.24-4.18; P =1.00) participants assigned to intensive BP lowering.
In patients with probable cerebral amyloid angiopathy, a crude analysis identified a significantly higher rate of hematoma volume expansion compared with patients without CMBs (55.6% vs 20.0%, respectively; RR, 2.78; 95% CI, 1.19-6.51; P =.04). After adjustment for several covariates, investigators found no significant difference between the groups (aRR, 1.79; 95% CI, 0.44-7.31; P =.42).
The lack of all magnetic resonance imaging sequences in ATACH-2 trial participants as well as the strict eligibility criteria represent 2 limitations of the analysis.
“Underlying vascular disease and particularly [cerebral small vessel disease] may have confounded the previously reported associations with mortality” and CMB, according to the investigators.
Shoamanesh A, Morotti A, Romero JM, et al. Cerebral microbleeds and the effect of intensive blood pressure reduction on hematoma expansion and functional outcomes: a secondary analysis of the ATACH-2 randomized clinical trial [published online April 16, 2018]. JAMA Neurol. doi:10.1001/jamaneurol.2018.0454