Warfarin Induced Coagulopathy- Prevalence, Risk Factors and Correlation of Bleeding Severity with INR Values - A Cross-sectional Study
DOI:
https://doi.org/10.65129/medical.v1i2.38Keywords:
Anticoagulation, Bleeding, Cross-sectional Study, INR, Polypharmacy, Risk Factors, WarfarinAbstract
Background: Warfarin, a commonly used oral anticoagulant, is associated with a significant risk of bleeding due to its narrow therapeutic index and multiple patient-specific influencing factors. Understanding the prevalence, severity, and predictors of bleeding is essential for optimizing patient safety. Aim and Objective: To determine the prevalence of bleeding among patients on Warfarin therapy and to identify risk factors for major and minor bleeding, with a focus on correlating bleeding severity with INR values. Materials and Methods: A hospital-based cross-sectional study was conducted over 3 months at the Institute of Internal Medicine, Rajiv Gandhi Government General Hospital, Chennai. A total of 76 adult patients on Warfarin (Acitrom) for at least three months were enrolled consecutively. Clinical history, concomitant medication usage, and INR levels were documented. Bleeding manifestations were assessed and classified as mild, moderate or severe. Laboratory investigations and imaging were performed as needed. Statistical analysis was done using SPSS v23, with a p-value <0.05 considered significant. Results: The prevalence of Warfarin-induced bleeding was 47.3% (n=36). Bleeding was significantly more common in females (p=0.003). Among those with bleeding (n=36), 52.45% were on 6-12 concomitant medications. Severity of bleeding did not show a significant association with gender (p=0.44). The most frequent bleeding sites were gastrointestinal (34.42%) and skin/ecchymosis (29.51%). Polypharmacy and female gender were identified as key predictors of bleeding. Conclusion: Nearly half of the patients on Warfarin therapy experienced bleeding complications, with female sex and polypharmacy being significant risk factors. Regular INR monitoring and minimization of concomitant medications are crucial to reduce bleeding risk. Clinicians must remain alert to bleeding signs, particularly in the gastrointestinal and cutaneous systems, to ensure prompt intervention.
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