Across 19 studies drawn from nine randomized controlled trials enrolling 10,594 participants, coronary artery bypass grafting (CABG) reduced all-cause mortality and repeat revascularization compared to percutaneous coronary intervention (PCI) in patients with diabetes and chronic kidney disease (CKD). No significant treatment difference emerged for myocardial infarction or stroke in those groups, nor for mortality or stroke in women or older adults. Patient-reported outcomes additionally favored CABG in diabetic patients. GRADE certainty ratings were Low to Very Low for most subgroups, rising to Moderate only for diabetes.
The diabetes finding aligns with a well-established mechanistic rationale: multivessel disease in diabetics involves diffuse atherosclerosis that stenting addresses incompletely, whereas CABG bypasses multiple lesions simultaneously. The CKD benefit is more provocative and clinically underappreciated, given that these patients are often steered toward PCI due to concerns about surgical risk and contrast nephropathy. Critically, the review exposes a near-total evidence vacuum for peripheral vascular disease and frailty — two comorbidities that are both common and prognostically decisive in real-world cardiac populations. The absence of blinding across included trials introduces performance and detection bias. As a preprint not yet peer-reviewed, these conclusions require independent validation before influencing clinical guidelines. Still, the moderate-certainty signal for diabetes is confirmatory and actionable, reinforcing existing guideline preferences for CABG in diabetic multivessel disease while highlighting urgent gaps for other high-risk subgroups.