Clinical outcomes off-pump comparing on-pump coronary artery bypass surgery in diabetic patients: updated systematic review and meta-analysis

BACKGROUND: Patients with diabetes mellitus are at high risk for coronary artery disease and frequently undergo coronary artery bypass grafting (CABG). Off-pump CABG (OPCAB) has been proposed to reduce perioperative complications compared with on-pump CABG (ONCAB), but long-term outcomes remain uncertain. METHODS: We conducted a systematic review and meta-analysis in accordance with PRISMA 2020 and Cochrane guidelines. Five databases were searched through May 2025 for randomized trials and observational cohorts comparing OPCAB and ONCAB in adults with diabetes. Risk of bias was assessed using RoB-2 and ROBINS-I, and evidence quality was graded with GRADE. RESULTS: Seventeen studies were included. No significant differences were observed in 30-day (RR = 0.82, 95% CI: 0.51-1.31; I² = 64%), 1-year (RR = 0.93, 95% CI: 0.56-1.55; I² = 65.6%), or 5-year mortality (RR = 1.09, 95% CI: 0.78-1.53; I² = 58.8%). Randomized data suggested a possible increase in late mortality with OPCAB. OPCAB was associated with lower rates of cerebrovascular events, pulmonary complications, reoperation for bleeding, prolonged ventilation, and intensive care unit stay. No differences were found in myocardial infarction, renal failure, atrial fibrillation, or sternal wound infection. Incomplete revascularization occurred more frequently with OPCAB (RR = 1.96, 95% CI: 1.28-3.0). CONCLUSIONS: In diabetic patients undergoing CABG, OPCAB may reduce postoperative morbidity without altering overall survival. These findings underscore the need to balance perioperative benefits against potential long-term risks when selecting the surgical approach.