Age-stratified predictors of mortality in coronary artery bypass grafting - a ten-year cohort study.

Aim: The aim of this study was to assess the predictors of mortality associated with coronary artery bypass grafting (CABG) in elderly patients. Methodology: This retrospective cohort study included all adult patients who underwent isolated CABG at a single institution between January 2015 and October 2024. Patients were stratified into three age groups: < 65 years, 65-74 years, and > 74 years. Demographic, operative, and postoperative outcomes were compared across groups. Multivariable logistic regression was performed for the entire cohort and separately for patients ≥ 65 years to identify independent predictors of in-hospital mortality. Results: A total of 9,309 patients underwent isolated CABG, including 6,489 patients aged < 65 years and 2,820 patients aged ≥ 65 years. Older patients had a higher prevalence of peripheral vascular disease (6.8% vs. 4.3%, p < 0.0001) and hypertension (83.0% vs. 79.9%, p = 0.001). Postoperative complications were significantly more frequent in the ≥ 65 group, including respiratory (21.5% vs. 16.9%, p < 0.0001), cardiovascular (3.0% vs. 1.6%, p < 0.0001), renal (1.1% vs. 0.4%, p = 0.002), gastrointestinal (1.0% vs. 0.7%, p = 0.011), and neurological events (3.4% vs. 1.5%, p < 0.0001). In-hospital mortality was nearly doubled in patients ≥ 65 years (2.0% vs. 1.1%, p = 0.001). Among those > 74 years, the incidence of blood transfusion (93.3%, p < 0.0001), respiratory (24.7%, p < 0.0001), and gastrointestinal complications (2.0%, p = 0.011) was further elevated. Multivariable logistic regression confirmed age as an independent predictor of mortality (Odds Ratio 1.05, 95% Confidence Interval: 1.03-1.07, p < 0.0001). Conclusions: Advancing age, along with chronic obstructive pulmonary disease, cardiopulmonary bypass use, and reduced ejection fraction, were independent predictors of in-hospital mortality following CABG. Supplementary Information: The online version contains supplementary material available at 10.1007/s12055-025-02013-7.