Evidence map›Paper›PMID 41566428›Full record

SynthesisInternational journal of stroke : official journal of the International Stroke Society2026

Does illicit drug use increase stroke risk? A systematic review, meta-analyses, and Mendelian randomization analysis.

Megan Ritson, Hugh S Markus, Eric L Harshfield

Abstract readSystematic ReviewMeta-Analysis
In one paragraph

Synthesis in International journal of stroke : official journal of the International Stroke Society, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

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4 · The record

Corrections and comments

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5 · Who and what money

Authors and funding

3 authors.

Megan RitsonDepartment of Clinical Neurosciences, University of Cambridge, Cambridge, UK.ORCID 0009-0009-0987-2829
Hugh S MarkusDepartment of Clinical Neurosciences, University of Cambridge, Cambridge, UK.ORCID 0000-0002-9794-5996
Eric L HarshfieldDepartment of Clinical Neurosciences, University of Cambridge, Cambridge, UK.ORCID 0000-0001-8767-0928

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundEpidemiological evidence suggests associations between substance use disorders and risk of stroke, but whether these are due to confounding or are true causal relationships remains uncertain.

aimsTo meta-analyze the observational evidence on illicit substance use and stroke risk and apply Mendelian randomization (MR) to evaluate potential causal effects of substance dependence on stroke subtypes.

methodsWe conducted a systematic review and meta-analysis of studies reporting associations between illicit drug use and stroke (PROSPERO registration-CRD420251053702). The meta-analysis included 32 studies comprising more than 100 million total participants across administrative, hospital-based, and population-based datasets. Pooled odds ratios (ORs) were estimated using multivariate random-effects models for ischemic and hemorrhagic subtypes. We then performed two-sample MR using genome-wide association study summary statistics to examine associations between seven drug exposures and all stroke, ischemic and hemorrhagic stroke, and ischemic stroke subtypes.

resultsMeta-analysis demonstrated significant associations of cannabis (OR = 1.37, 95% confidence interval (95% CI) = 1.14-1.65), cocaine (OR = 1.96; 95% CI = 1.27-3.01), and amphetamines (OR = 2.22, 95% CI = 1.40-3.53) with increased stroke risk, while no significant association was observed for opioids. Findings for cannabis showed some heterogeneity and small-study effects. MR analyses revealed that cannabis use disorder was associated with any stroke (OR = 1.11 [1.01-1.51]) and large artery stroke (OR = 1.35, 95% CI = 1.01-1.80), and cocaine dependence was associated with cardioembolic stroke (OR = 1.08, 95% CI = 1.02-1.14) and intracerebral hemorrhage (OR = 1.38, 95% CI = 1.15-1.65). Genetically predicted substance use disorder overall was associated with any stroke (OR = 1.33, 95% CI = 1.02-1.72) and intracerebral hemorrhage (OR = 7.79, 95% CI = 3.46-17.54). Problematic and dependent alcohol use was linked to large artery and cardioembolic stroke, whereas nicotine dependence showed no significant associations.

conclusionOur findings provide consistent observational and genetic evidence that several forms of substance misuse increase stroke risk, particularly cocaine, amphetamines, and cannabis. These findings suggest important public health implications for prevention strategies targeting substance use disorders to mitigate stroke risk.

Indexed as

Illicit DrugsStrokeSubstance-Related DisordersHumansMendelian Randomization AnalysisRisk FactorsIllicit DrugsIllicit drugsmeta-analysisMR analysisstrokesubstance-related disorderssystematic review

Identifiers

PMID41566428
PMCPMC13291408

What Socratic holds

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LicenceCC BY
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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.