Summary
Background
Cerebral microbleeds are a neuroimaging biomarker of stroke risk. A crucial clinical question is whether cerebral microbleeds indicate patients with recent ischaemic stroke or transient ischaemic attack in whom the rate of future intracranial haemorrhage is likely to exceed that of recurrent ischaemic stroke when treated with antithrombotic drugs. We therefore aimed to establish whether a large burden of cerebral microbleeds or particular anatomical patterns of cerebral microbleeds can identify ischaemic stroke or transient ischaemic attack patients at higher absolute risk of intracranial haemorrhage than ischaemic stroke.
Methods
We did a pooled analysis of individual patient data from cohort studies in adults with recent ischaemic stroke or transient ischaemic attack. Cohorts were eligible for inclusion if they prospectively recruited adult participants with ischaemic stroke or transient ischaemic attack; included at least 50 participants; collected data on stroke events over at least 3 months follow-up; used an appropriate MRI sequence that is sensitive to magnetic susceptibility; and documented the number and anatomical distribution of cerebral microbleeds reliably using consensus criteria and validated scales. Our prespecified primary outcomes were a composite of any symptomatic intracranial haemorrhage or ischaemic stroke, symptomatic intracranial haemorrhage, and symptomatic ischaemic stroke. We registered this study with the PROSPERO international prospective register of systematic reviews, number CRD42016036602.
Findings
Between Jan 1, 1996, and Dec 1, 2018, we identified 344 studies. After exclusions for ineligibility or declined requests for inclusion, 20 322 patients from 38 cohorts (over 35 225 patient-years of follow-up; median 1·34 years [IQR 0·19–2·44]) were included in our analyses. The adjusted hazard ratio [aHR] comparing patients with cerebral microbleeds to those without was 1·35 (95% CI 1·20–1·50) for the composite outcome of intracranial haemorrhage and ischaemic stroke; 2·45 (1·82–3·29) for intracranial haemorrhage and 1·23 (1·08–1·40) for ischaemic stroke. The aHR increased with increasing cerebral microbleed burden for intracranial haemorrhage but this effect was less marked for ischaemic stroke (for five or more cerebral microbleeds, aHR 4·55 [95% CI 3·08–6·72] for intracranial haemorrhage
vs
1·47 [1·19–1·80] for ischaemic stroke; for ten or more cerebral microbleeds, aHR 5·52 [3·36–9·05]
vs
1·43 [1·07–1·91]; and for ≥20 cerebral microbleeds, aHR 8·61 [4·69–15·81]
vs
1·86 [1·23–2·82]). However, irrespective of cerebral microbleed anatomical distribution or burden, the rate of ischaemic stroke exceeded that of intracranial haemorrhage (for ten or more cerebral microbleeds, 64 ischaemic strokes [95% CI 48–84] per 1000 patient-years
vs
27 intracranial haemorrhages [17–41] per 10...
WMH score was associated with poor post-stroke cognitive performance. Adding other SVD markers or SVD burden score, however, did not improve prediction.
To examine the association of diabetes and glycated hemoglobin (HbA 1c) with the risk of intracerebral hemorrhage (ICH) in a large population-based cohort. RESEARCH DESIGN AND METHODS The computerized database of the largest health care provider in Israel was used to identify adult members aged 40 years or older and alive at 1 January 2010 (297,486 with diabetes and 1,167,585 without diabetes). The cohort was followed until 31 December 2017 for incidence of ICH. Multivariable Cox proportional hazards regression models, adjusted for baseline disease risk score, were applied to estimate the hazard ratio (HR) of ICH. RESULTS Overall 4,170 ICH cases occurred during 10,730,915 person-years of follow-up. Diabetes was independently associated with increased ICH risk, with hazard ratio (HR) 1.36 (95% CI 1.27-1.45), and increased with longer diabetes duration: 1.23 (1.12-1.35) and 1.44 (1.34-1.56) for diabetes duration £5 years and >5 years, respectively. The increased ICH risk associated with diabetes was more pronounced in patients £60 years old (P interaction <0.001). Among patients with diabetes, HbA 1c had a nonlinear J-shaped relationship with ICH (P for nonlinearity = 0.0186). Compared to the fourth HbA 1c decile, 6.5-6.7% (48-50 mmol/mol), the HR for ICH was 1.27 (1.01-1.59) and 2.19 (1.75-2.73) in the lowest HbA 1c decile, £6.0% (£42 mmol/ mol), and highest HbA 1c decile, >9.3% (>78 mmol/mol), respectively. CONCLUSIONS Diabetes is associated with increased risk of ICH that is directly associated with diabetes duration. ICH and HbA 1c appear to have a J-shaped relationship, suggesting that both poor control as well as extreme intensive diabetes control might be associated with increased risk. Spontaneous intracerebral hemorrhage (ICH) is a devastating condition accounting for 10-15% of all stroke cases. It is associated with a dismal prognosis, as only 38% of affected patients survive the first year (1). Type 2 diabetes affects more than 415 million adults worldwide and is a well-known contributor to cardiovascular morbidity, cognitive decline, and all-cause mortality (2). Although diabetes is an independent risk factor for ischemic stroke (3), as yet there
Research in context panel: 445Identifying people at highest risk of ICH may facilitate timely and accurate prognostication to allow mitigation of reversible risk factors for bleeding (e.g. intensive blood pressure control), and selection of participants for clinical trials. While more complex combinations of clinical, biochemical, and radiological markers might further improve stroke risk prediction, balancing accuracy with simplicity will remain important.
This study confirms that the risk of ICH decreases with increasing cholesterol levels, but suggests that statin use might be associated with decreased risk of ICH.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.