Prognostic value of HbA1c and plasma glucose on one-year mortality in non-diabetic patients after myocardial infarction

Background: The usefulness of the combined assessment of HbA1c and plasma glucose (PG) in acute myocardial infarction (AMI) in non-diabetic patients remains unclear. Purpose: In a large observational study, we aimed to identify the prognostic values of these biomarkers regarding one-year all-cause mortality in non-diabetic patients after AMI. Methods: From the “obseRvatoire des Infarctus de Côte d'Or” (RICO) survey database, we included all consecutive non-diabetic patients with AMI (n = 6617) from May 2001 to December 2016. Exclusion criteria were: admission known or unknown diabetes, in-hospital death. The primary endpoint was all-cause one-year mortality. The secondary endpoints were: MACE, infarct size, LVEF < 40% and GRACE risk score. Cut-off levels (high/low) were determined by ROC curve analysis for the prediction of one-year death (HbA1c 5.9% and PG 131 mg/dL) to set up 4 groups: low HbA1c/low glucose (n = 3158), low HbA1c/high glucose (n = 1264), high HbA1c/low glucose (n = 1378) and high HbA1c/high glucose (n = 817). Results: Elevation of PG was associated with elevated rate of LVEF < 40%, STEMI, anterior wall location, DFG < 60 mL/min/m2 and higher troponin Ic pic (all P < 0.001); HbA1c > 5.9% was associated with elevated rate of CRP > 3 mg/L (P < 0.001); high HbA1c and high PG together were associated with higher rate of MACE (P < 0.001). By multivariate logistic regression analysis, elevated admission PG remained a strong predictor of one-year all-cause [OR (95%CI): 1.64 (1.31–2.05)] mortality and cardiovascular mortality [OR (95%CI): 1.75 (1.33–2.31)], beyond GRACE score [OR (95%CI): 1.03 (1.03–1.04)], as well as elevated HbA1c [OR (95%CI): 1.43 (1.15–1.78) and OR (95%CI): 1.83 (1.39–2.41) respectively]. Conclusions: Admission PG and HbA1c had strong independent predictive value regarding one-year all-cause mortality in our non-diabetic patients with AMI. These biomarkers could be useful to identify the most-at-risk patients after AMI in order to reduce residual risk in this target population.