Impact of diabetes mellitus on all and successful percutaneous coronary intervention outcomes for chronic total occlusions: A systematic review and meta-analysis

Background Diabetes mellitus (DM) is a leading cause of morbidity and mortality globally and can affect numerous vital organs, including the kidney, liver, heart, nervous system, and vascular system. Objective To assess the impact of type 2 diabetes mellitus (DM) on outcome in patients undergoing percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). Methods Academic databases were screened for eligible studies published prior to January 2021. Study quality was assessed using Cochrane's risk of bias tool and the Newcastle Ottawa scale. Results Pooling studies that met inclusion criteria, we carried out a meta-analysis with a random-effects model and reported pooled odds ratios (ORs) with 95% confidence intervals (CIs). A total of ten studies featuring 8,276 participants met eligibility criteria. Type 2 DM patients had significantly higher odds of mortality (pooled OR: 1.62; 95% CI: 1.10 to 2.37), revascularization (pooled OR: 1.41; 95% CI: 1.14 to 1.74) and major adverse cardiac events (MACE) (pooled OR: 1.39; 95% CI: 1.18 to 1.63) relative to non-DM patients following PCI for CTO (regardless of PCI success or failure). Similarly, even when only looking at patients who underwent successful PCI, type 2 DM patients had significantly higher odds of revascularization (pooled OR: 1.54; 95% CI: 1.20 to 1.97) and MACE (pooled OR: 1.35; 95% CI: 1.13 to 1.63). Conclusion Type 2 DM significantly impacts the risk for adverse clinical outcomes even after successful PCI for CTO. As such, clinicians need to develop a comprehensive intervention package for DM patients with cardiovascular disease.