Outcomes of Prediabetes Compared with Normoglycaemia and Diabetes Mellitus in Patients Undergoing Percutaneous Coronary Intervention: A Systematic Review and Meta-analysis

Background: Patients with prediabetes are at increased risk of coronary artery disease (CAD). However, the association between prediabetes and adverse clinical outcomes following percutaneous coronary intervention (PCI) is inconsistent, in contrast to outcomes in patients with diabetes mellitus (DM). Thus, this meta-analysis evaluated the impact of dysglycaemia on PCI outcomes. Methods: The PubMed, Embase, Cochrane, and ClinicalTrials.gov databases were systematically reviewed from inception of databases until June 2022. In 17 studies, outcomes of PCI in patients with prediabetes were compared with patients who were normoglycaemic, and patients with DM. The primary outcome was all-cause mortality at the longest follow-up. Results: Included were 12 prospective and five retrospective studies, with 11,868, 14,894 and 13,536 patients undergoing PCI in the prediabetes, normoglycaemic and DM groups, respectively. Normoglycaemic patients had a statistically lower risk of all-cause mortality, (risk ratio [RR] 0.66, 95% confidence interval [CI] 0.52–0.84), myocardial infarction (MI; RR 0.76, 95% CI 0.61–0.95) and cardiac mortality (RR 0.58, 95% CI 0.39–0.87) compared with prediabetic patients undergoing PCI at the longest follow-up. Patients with prediabetes had a lower risk of all-cause mortality (RR=0.72 [95% CI 0.53–0.97]) and cardiac mortality (RR =0.47 [95% CI 0.23–0.93]) compared with patients with DM who underwent PCI. Conclusion: Among patients who underwent PCI for CAD, the risk of all-cause and cardiac mortality, major adverse cardiovascular events and MI in prediabetic patients was higher compared with normoglycaemic patients but lower compared with patients with DM.