American Society of Hirudotherapy

Identifying risk factors for major bleeding in patients with atrial fibrillation using direct oral anticoagulants: a systematic review and meta-analysis

Research article published in Journal of thrombosis and haemostasis : JTH (2026)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Research reportClinical TrialsWang X et al. · Journal of thrombosis and haemostasis : JTH, 2026

Abstract

BACKGROUND: Major bleeding (MB) remains a serious complication in atrial fibrillation (AF) patients treated with direct oral anticoagulants (DOACs), but effect estimates for individual factors vary across studies and have not been synthesized in a DOAC-specific framework. OBJECTIVES: To provide a comprehensive DOAC-specific synthesis of risk factors associated with MB in AF patients. METHODS: We systematically searched PubMed, Embase, and the Cochrane Library from their inception to December 2024. We included studies of DOAC-treated AF patients that reported associations between patient characteristics and MB. Random-effects meta-analyses were conducted when at least 2 studies evaluated the same risk factors using comparable definitions. Prespecified subgroup analyses were performed for the MB outcome and for individual DOAC agents. RESULTS: Eighty-three studies involving 970 248 patients were included. Twenty-one variables were associated with MB. We confirmed several well-known risk factors for MB, including a history of bleeding, alcohol use, age ≥65 years, frailty, and high HAS-BLED (Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio, Elderly (>65 years), and Drugs/alcohol concomitantly) score. Importantly, this DOAC-focused synthesis also highlighted additional and previously underemphasized risk factors, including cancer, myocardial infarction or peripheral artery disease, heart failure, coronary artery disease, and the use of psychotropic or antiarrhythmic drugs. Overweight status and statin use were associated with a lower MB risk, although these findings should be interpreted with caution. CONCLUSION: This meta-analysis provides an integrated, DOAC-specific, quantitative overview of MB risk factors across multiple clinical and treatment domains. The pooled estimates provide a contemporary evidence base to prioritize variables for refinement, recalibration, and validation of MB risk assessment strategies in DOAC-treated AF populations.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal Article

Summary

Major bleeding (MB) remains a serious complication in atrial fibrillation (AF) patients treated with direct oral anticoagulants (DOACs), but effect estimates for individual factors vary across studies and have not been synthesized in a DOAC-specific framework.

Why This Matters for Hirudotherapy

This systematic review and meta-analysis pooled 83 studies (970,248 patients) to identify 21 variables associated with major bleeding in atrial-fibrillation patients on direct oral anticoagulants, confirming known factors (prior bleeding, alcohol use, age >=65, frailty, high HAS-BLED) and surfacing underemphasized ones (cancer, heart failure, coronary/peripheral artery disease, psychotropic or antiarrhythmic drugs). The ASH relevance is contextual and cautionary: by systematically cataloguing who bleeds on systemic anticoagulation, it underscores the safety considerations any anticoagulant must address -- including the medicinal-leech secretome, whose antithrombotic peptides act through different mechanisms but share the same fundamental bleeding-risk concern. Honest caveat: this synthesis covers pharmaceutical DOACs exclusively, makes no mention of leeches or hirudotherapy, and its observational source studies preclude causal claims about any individual risk factor or about leech-based treatment.

Citation

Identifying risk factors for major bleeding in patients with atrial fibrillation using direct oral anticoagulants: a systematic review and meta-analysis.

Wang X et al. · Journal of thrombosis and haemostasis : JTH, 2026

Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026

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