Prognostic effect of prediabetes defined by different criteria in patients with moderate-to-severe coronary artery calcification: a prospective cohort study

Abstract Background Although prediabetes has been recognized as a contributor to the presence and progression of coronary artery calcification, its prognostic significance in individuals with moderate-to-severe coronary artery calcification (MSCAC) remains unclear. Purpose This study aimed to evaluate the prognostic significance of prediabetes in MSCAC patients, using different glycaemic classification thresholds established by the American Diabetes Association (ADA) and the World Health Organization (WHO)/International Expert Committee (IEC). Methods In this prospective cohort study, we consecutively enrolled 4323 patients with angiography-detected MSCAC. Prediabetes was defined according to ADA criteria as fasting plasma glucose (FPG) of 5.6–6.9 mmol/L and/or hemoglobin A1c (HbA1c) of 5.7–6.4%, while WHO/IEC criteria classified prediabetes as FPG of 6.1–6.9 mmol/L and/or HbA1c of 6.0–6.4%. The primary outcome was major adverse cardiovascular events (MACE), encompassing cardiovascular death, nonfatal myocardial infarction, and stroke. Results The mean age of the cohort was 61.9 ± 10.1 years, and 3,253 (75.2%) were male. The prevalence of prediabetes defined by ADA criteria (36.8%) was twice that of WHO/IEC criteria (18.3%) (Figure 1). Over a median follow-up of 3.1 years, the incidence of MACE was 2.2% in individuals with normoglycaemia, 3.5% in those with prediabetes, and 5.6% in those with diabetes according to ADA criteria, whereas the corresponding incidences based on WHO/IEC criteria were 2.2%, 4.8%, and 5.6%, respectively. Compared with patients with normoglycaemia, those with WHO/IEC-defined prediabetes had a significantly higher risk of MACE after adjustment for baseline clinical risk factors adjusted hazard ratio (HR) 1.842, 95% confidence interval (CI) 1.150–2.951, primarily driven by an increased incidence of events among individuals with HbA1c-defined prediabetes (Figure 2). However, this association was not observed in patients classified as prediabetic according to ADA criteria (adjusted HR 1.477, 95% CI 0.844–2.586) (Figure 2). Conclusion This large-scale cohort study highlights the prognostic value of prediabetes, as defined by WHO/IEC criteria, in patients with MSCAC. These findings support the utility of WHO/IEC glycaemic thresholds in identifying individuals at heightened cardiovascular risk among these patients.Figure 1 Figure 2