Association between preoperative C-reactive protein-to-albumin ratio and postoperative atrial fibrillation in patients undergoing isolated coronary artery bypass grafting

Objectives: The association between preoperative C-reactive protein-to-albumin ratio (CAR) and postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) has not been clearly established.We therefore investigated the relationship between preoperative CAR and POAF in patients undergoing isolated CABG.Patients and methods: This retrospective analysis included 200 adults treated with isolated CABG during 2025-2026.POAF developed in 47 patients, whereas 153 remained free of POAF.Clinical, laboratory, and perioperative data were evaluated in relation to postoperative rhythm status.CAR was obtained from preoperative C-reactive protein and albumin measurements.Associations between selected clinical variables, CAR, and POAF were evaluated using logistic regression.Results: POAF was documented in 47 patients (23.5%).Patients with POAF had a median age of 66.0 (57.5-72.5)years, compared with 62.0 (54.0-66.0)years in those without POAF (p=0.003).Median CAR values were 0.048 (0.038-0.243) and 0.045 (0.038-0.185), respectively (p=0.700).Acute kidney injury was observed in 23.4% of the POAF group and 7.8% of the non-POAF group (p=0.003).Patients with POAF had longer intensive care unit and hospital stays (p<0.001 and p=0.004, respectively).After adjustment for the variables included in the model, age remained independently associated with POAF (odds ratio [OR]=1.065;95% confidence interval [CI]: 1.022-1.109;p=0.003), while an independent association was not demonstrated for CAR per 0.01-unit increase (OR=1.003;95% CI: 0.994-1.012;p=0.518). Conclusion:An independent association between preoperative CAR and POAF could not be demonstrated in this cohort.Increasing age remained independently associated with POAF.Larger prospective studies are needed to clarify the relationship between preoperative CAR and POAF.