After index intracerebral hemorrhage (ICH), risk of recurrent ICH, ischemic stroke, and all serious vascular events differed by ICH location and whether atrial fibrillation (AFib) was present, data from two population-based studies showed.
Lobar ICH was associated with higher risk of recurrent ICH (HR 3.2, 95% CI 1.6-6.3, P=0.001) than non-lobar location, but no higher risk of ischemic stroke (HR 1.1, 95% CI 0.5-2.8), reported Rustam Al-Shahi Salman, FRCP of University of Edinburgh, U.K., and co-authors in Lancet Neurology.
Patients with AFib had higher risk of ischemic stroke than those without AFib (HR 8.2, 95% CI 3.3-20.3, P<0.0001), but no higher recurrent ICH risk (HR 0.9, 95% CI 0.4–2.1).
“Lobar ICH location can be used to stratify patients according to their risk of recurrent ICH, and comorbid AFib can be used to stratify risk of ischemic stroke and all serious vascular events after ICH,” Salman and colleagues wrote.
“Given the apparent benefit of blood pressure lowering in reducing the risk of recurrent lobar ICH, the high frequency of recurrent ICH after lobar ICH should encourage greater use of blood pressure lowering therapy,” they added. “Further research is needed to achieve larger sample sizes to explore risk stratification with greater precision and develop prognostic models.”
The researchers combined data from two prospectively followed, population-based cohort studies of patients with first-ever ICH from Oxfordshire, England (OXVASCLATCH
The group also compared pooled event rates for those using antiplatelet therapy prior to their index ICH in this pooled cohort with those in a third study, RESTART, who were not restarted on antiplatelet therapy after index ICH. Risk for all serious vascular events (non-fatal stroke, non-fatal myocardial infarction, or vascular death) was higher in ICH patients with AFib than in those without (HR 1.78, 95% CI 1.16-2.74; P=0.0090). Patients with lobar ICH but no AFib were the only subgroup with risk of recurrent ICH greater than risk of ischemic stroke (5.2 per 100 patient-years, 95% CI 3.6-7.5 versus 0.9 per 100 patient-years, 95% CI 0.2-4.8, P=0.00034). The pooled cohort did not differ from those not receiving antiplatelet therapy in RESTART on outcomes of recurrent ICH (3.5 per 100 patient-years, 95% CI 1.9-6.0 versus 4.4 per 100 patient-years, 95% CI 2.6–6.1, respectively) or ischemic stroke (3.4 per 100 patient-years, 95% CI 1.9-5.9 versus 5.3 per 100 patient-years, 95% CI 3.3-7.2, respectively). Uncertainty about risks leaves clinicians with dilemmas about using antithrombotic therapy for secondary prevention of major vascular events after ICH, noted Xin Cheng, MD, PhD, and Qiang Dong MD, both of Fudan University in Shanghai, China, in an accompanying editorial. The decision about whether to use anticoagulants in ICH, especially in lobar ICH survivors with comorbid AFib, is being investigated in several ongoing trials of direct oral anticoagulants but in patients without AFib, the decision about antiplatelet therapy is unclear, they added. “In the only completed randomized controlled trial, RESTART, starting antiplatelet therapy seemed safe and reduced major vascular events compared with avoiding antiplatelet therapy over 2 years, without evidence of heterogeneity of the effects of antiplatelet therapy by clinical or imaging characteristics,” Cheng and Dong wrote. “Although the results of RESTART were reassuring, the findings need to be externally validated in different populations.” The pooled cohort of OXVASC and LATCH participants had mean age about 75 and 53% were female. AF was present pre-ICH in 22% overall and did not differ between those with lobar ICH (20%) and non-lobar ICH (24%). Antithrombotic drugs were used by 51% of all participants prior to ICH, with no significant difference in rate of use for lobar versus non-lobar ICH. After ICH at discharge, antithrombotic medication was received by 6%; lobar versus non-lobar recipients were treated at rates of 7% and 5%, respectively. Hypertension was the most common risk factor—present in 64% of all participants and was the only risk factor that differed significantly between lobar and non-lobar ICH groups (56% for lobar ICH versus 71% for non-lobar ICH, P<0.00001). Diabetes, hyperlipidemia, and current smoking were similar between the groups. “Although both cohorts were similar in the directions and magnitudes of the associations with risk factors of interest, the absolute risks of outcome events were higher in LATCH than OXVASC, probably owing to differences that we found in the prevalence of risk factors for vascular disease and in the uptake of secondary prevention drugs before ICH, as well as the known higher burden of cardiovascular disease in Scotland compared with England,” Salman and colleagues observed. Limitations of the study included minimal MRI data, which was not available in 95% of the cohort. In addition, interactions between ICH location and AF were not analyzed, and results were not adjusted for use of antithrombotic drugs after discharge. The population was predominantly white, limiting generalizability to other populations. After index intracerebral hemorrhage (ICH), risk of recurrent ICH, ischemic stroke, and all serious vascular events differed by ICH location and whether atrial fibrillation (AFib) was present, data from two population-based studies showed. Lobar ICH was associated with higher risk of recurrent ICH, but no higher risk of ischemic stroke. Patients with AFib had higher risk of ischemic stroke, but no higher recurrent ICH risk . Paul Smyth, MD, Contributing Writer, BreakingMED™ This study was funded by the UK Medical Research Council, Stroke Association, British Heart Foundation, Wellcome Trust, and the National Institute for Health Research Oxford Biomedical Research Centre. Salman reported grants from the Medical Research Council during the conduct of the study. The editorialists declared no competing interests. Cat ID: 38 Topic ID: 82,38,730,8,913,914,38,192,925
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