Risk factors for major bleeding among patients with chronic kidney disease treated with acetylsalicylic acid

Introduction: Individuals with chronic kidney disease (CKD) are at increased risk of thrombotic events and bleeding. Acetylsalicylic acid (ASA), an effective antiplatelet agent, is one of the most frequently used medications for both primary and secondary prevention of cardiovascular disease (CVD). However, it can also contribute to bleeding events due to its inherent antiplatelet effect. The objective of this study was to determine the characteristics of CKD patients at increased risk of bleeding under ASA therapy. Methods: This retrospective analysis included patients with non-dialysis-dependent CKD who were treated with ASA for primary prevention of CVD for at least 3 consecutive months and did not receive anti-coagulants or anti-platelets. Data were collected from electronic medical records from January 2014 to December 2018. CKD diagnosis was based on an estimated glomerular filtration rate of <60 mL/min/1.73 m2. CKD patients who experienced major bleeding events during ASA therapy (bleeding group) versus all others (control group) were compared. Additional outcomes included first documented nonfatal cardiovascular event and all-cause mortality. Results: Of the 900 adult CKD patients included in this analysis, 82 (9.1%) had a major bleeding event during 31.6 ± 25.9 months of follow-up. The most common bleeding site was gastrointestinal (52 cases, 63.4% of major bleeding events). Patients who had a major bleeding event were older (76.5 ± 10 vs. 74 ± 10.3 years, p = 0.038). On multivariate analysis, age was the most important predictor of major bleeding event (odds ratio: 1.029, 95% confidence interval: 1.004–1.056). Conclusions: Given its controversial efficacy in primary prevention of CVD in CKD patients, characterizing those at increased risk of bleeding under ASA therapy is important in the era of tailored medicine. Age, CKD stage, and cardiovascular risk are key factors to consider regarding the safety and effectiveness of ASA for CKD patients.