American Society of Hirudotherapy

Clinical impact of kidney function in patients with atrial fibrillation receiving oral anticoagulants

Research article published in International journal of cardiology (2025)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Research reportClinical TrialsMatsuoka et al. · International journal of cardiology, 2025

Abstract

BACKGROUND: Renal function influences the pharmacokinetics of oral anticoagulants in atrial fibrillation (AF), potentially affecting both efficacy and bleeding risk. However, its differential impact across specific agents remains unclear. In this study, we aimed to evaluate the association between renal function and ischemic and bleeding risks in patients with AF, with analyses stratified by anticoagulant type. METHODS: We analyzed 7239 patients with non-valvular AF from the DIRECT-Extend registry, a pooled dataset of three large-scale registries. Creatinine clearance (CrCl) was calculated using the Cockcroft-Gault formula and categorized into ≥50, 30 to <50, and 15 to <30 mL/min. The primary ischemic endpoint was stroke or systemic embolism, and the primary bleeding endpoint was major bleeding. Cox proportional hazard models and restricted cubic spline analyses assessed associations between CrCl and outcomes, with subgroup analyses by anticoagulant type. RESULTS: Lower CrCl was associated with older age, female sex, and greater comorbidity burden. Impaired renal function was significantly associated with higher ischemic and bleeding risks. Spline analysis demonstrated a continuous increase in both risks with declining CrCl, with a nonlinear relationship for bleeding. Subgroup analyses revealed significant associations between reduced CrCl and ischemic risk in patients on dabigatran, rivaroxaban, edoxaban, and warfarin. Increased bleeding risk was evident for edoxaban and warfarin at lower CrCl levels. No significant association was observed between CrCl and either endpoint in patients receiving apixaban. CONCLUSION: In this large real-world cohort, declining renal function was associated with increased ischemic and bleeding risks, highlighting the importance of renal function-based risk assessment in the management of anticoagulation therapy.

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

Publication typeJournal Article

Summary

Peer-reviewed clinical and outcomes research relevant to medicinal leech therapy and its biology. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This study used the pooled DIRECT-Extend registry of 7,239 non-valvular atrial fibrillation patients to examine how kidney function relates to ischemic and bleeding risk across specific oral anticoagulants; declining creatinine clearance was associated with continuously rising ischemic and bleeding risks, with significant ischemia associations for dabigatran, rivaroxaban, edoxaban, and warfarin, increased bleeding for edoxaban and warfarin, and no significant association for apixaban, underscoring renal-function-based risk assessment. Its hirudotherapy relevance is contextual: dabigatran is an oral direct thrombin inhibitor that targets the same enzyme as the leech peptide hirudin, so the data help map the safety profile of the thrombin-inhibition pathway that anchors the leech-derived antithrombotic story. Caveat: this is a real-world observational cohort of synthetic oral anticoagulants — it does not study medicinal-leech therapy or hirudin, associations are not causal, and findings reflect agent- and renal-specific pharmacokinetics rather than any leech-related claim.

Citation

Clinical impact of kidney function in patients with atrial fibrillation receiving oral anticoagulants.

Matsuoka et al. · International journal of cardiology, 2025

Added to ASH library: May 29, 2026 · Site last updated: June 18, 2026

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