Prevalence of prediabetes in patients with acute coronary syndrome: impact on in-hospital outcomes

Background Prediabetes is a serious condition that is associated with an increase in cardiovascular morbidity and mortality. Aims We sought to explore the prevalence of prediabetes in patients admitted with acute coronary syndrome (ACS) who were not known to have diabetes and to determine the impact of prediabetes on in‐hospital clinical outcomes versus non‐diabetic patients. Methods Prospectively, we enrolled 200 patients not known to have diabetes or prediabetes, admitted with ACS. Laboratory tests included fasting plasma glucose (FPG), 2‐h plasma glucose (2hPG) after 75 g glucose, HbA1c and lipid profile. Electrocardiogram and echocardiography were done. The primary end‐point was in‐hospital major adverse cardiovascular events (MACE). Results Mean age was 50.9 ± 6.8 years (70.5% males). The prevalence of patients with diabetes and patients with prediabetes was 24.5% and 20% respectively. Newly discovered diabetic patients were excluded. Compared with patients without diabetes, prediabetic patients had a higher body mass index (BMI) (P = 0.002) and a longer hospital stay (P = 0.09). In‐hospital MACE occurred in 10 (25%) patients with prediabetes versus six (5.4%) in patients without diabetes (P = 0.001). In‐hospital MACE correlated with prediabetes (r = 0.28, P < 0.001), BMI (r = 0.14, P = 0.093), FPG (r = 0.19, P = 0.014), 2hPG (r = 0.19, P = 0.017) and HbA1c (r = 0.19, P = 0.019). Multivariate regression analysis identified prediabetes as the only independent predictor of in‐hospital MACE. Conclusions Prediabetes is common in patients presenting with ACS who are not previously known to have diabetes. Prediabetic patients had worse in‐hospital clinical outcomes compared with patients without diabetes.