Short and long-term prognostic value of admission glycosylated hemoglobin and plasma glucose in nondiabetic patients with acute myocardial infarction

Abstract

In nondiabetic patients with acute myocardial infarction (AMI), acute hyperglycemia is associated with high risk of cardiovascular (CV) mortality but the prognostic value of glycosylated hemoglobin (HbA1c) remains uncertain. In a large observational study, we aimed to identify the prognostic values of admission HbA1c and plasma glucose for acute MI in nondiabetic patients regarding in-hospital and one-year CV mortality. From the RICO survey database all the consecutive nondiabetic patients with AMI ( n = 6884) from January 2001 to June 2016 were included. Cut off levels (high/low) were determined by ROC curve analysis for the prediction of CV one-year death (HbA1c: 5.9% and glucose: 156 mg/dL) to set up 4 groups: low HbA1c/low glucose ( n = 3849), low HbA1c/high glucose ( n = 734), high HbA1c/low glucose ( n = 1802) and high HbA1c/high glucose ( n = 499). Elevation of glucose or HbA1c was associated with elevated rate of hospital mortality, when compared to all other groups ( Fig. 1 ). By multivariate logistic regression analysis, only high glucose remains a prognostic factor of hospital death [OR(95% CI): 1.59 (1.16–2.17)]. In survivors at discharge, group with elevated levels of both plasma glucose and HbA1c had a higher rate of one-year CV mortality compared to all other groups ( P < 0.001). High HbA1c was an independent predictive factor of one-year CV mortality, beyond high glucose [OR(95% CI): 1.75 (1.35–2.27) and 1.98 (1.49–2.61), respectively] and covariates ( Fig. 1 ). In our large population-based study in nondiabetic patients with AMI, high levels of admission HbA1c and/or plasma glucose give different prognostic information and were associated with increased risk of mortality at short or long term. Early mortality risk was mainly driven by acute hyperglycemia and one-year mortality by HbA1c, independently of plasma glucose. Our findings may help identifying high-risk patients to target for aggressive secondary prevention after AMI.