A majority of patients with no history of diabetes who were admitted to the hospital with acute myocardial infarction (AMI) had disturbed glucose metabolism, according to results of an observational cohort study, published in Cardiovascular Diabetology.
Patients (N=841) with AMI and no known history of diabetes admitted to the Department of Cardiology at Danderyd University Hospital in Sweden between 2006 and 2013 were included in this study. Screening for undiagnosed diabetes was performed by hemoglobin A1c (HbA1c) assessment and by an oral glucose tolerance test (OGTT) following an overnight fast. Clinical outcomes were assessed on the basis of glucose metabolism status.
Patients had normal glucose metabolism (16.5%), were in the prediabetes range (47.3%), or had newly diagnosed diabetes (36.2%). These patient cohorts had a median age of 63 (interquartile range [IQR], 54-69), 64 (IQR, 58-71), and 66 (IQR, 58-71) years (P =.019); 74.8%, 76.4%, and 69.7% were men; and their median body mass index (BMI) was 25 (IQR, 23-28), 27 (IQR, 24-30), and 28 (IQR, 25-30), respectively (P <.001).
Normal glucose metabolism was observed among only 10% of patients for both the HbA1c assay and OGTT. Approximately one-third of patients (37%) exhibited dysglycemia at fasting plasma glucose, 2-hour plasma glucose, and HbA1c assessments.
The concurrence between HbA1c assay and OGTT was 62%.
Over an average follow-up of 6.9 years, the mortality rate was 12.8%, and 20.8% had a myocardial infarction, 14.3% were hospitalized for heart failure, and 2.3% had an ischemic stroke.
Stratified by glycemic metabolism status, the composite endpoint of cardiovascular events occurred among 41.7% of the normal glucose, 43.7% of the prediabetes, and 46.1% of the diabetes cohorts.
According to the HbA1c assessment, the normal glucose metabolism group had a significantly longer time free from composite cardiovascular events compared with the prediabetes cohort (P =.008) but did not differ from the diabetes cohort (P =.312). No significant difference was observed between normal glucose metabolism compared with the prediabetes (P =.971) or diabetes cohorts (P =.887), according to the OGTT.
The investigators assessed which cutoffs were best at predicting the composite cardiovascular outcome. For scenarios in which patients were separated into 3 categories (normal, prediabetes, or diabetes), the American Diabetes Association (ADA; <39 vs 39-47 vs ³48 mmol/mol) and World Health Organization (WHO; <42 vs 42-47 vs ³48 mmol/mol) cutoffs had similar performance.
For separating patients into 2 groups (normal or abnormal), the ADA criteria (<39 vs ³39 mmol/mol) outperformed the WHO criteria (<42 vs ³42 mmol/mol).
This study may have been limited by not having access to data about changes to lifestyle, which could have altered the long-term trajectory of some patients.
The study authors concluded the majority of patients presenting with AMI who had no history of diabetes had dysglycemia, underscoring the importance of routinely screening these patients for glucose metabolism.
Disclosure: Some authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Karayiannides S, Djupsjö C, Kuhl J, et al. Long‑term prognosis in patients with acute myocardial infarction and newly detected glucose abnormalities: predictive value of oral glucose tolerance test and HbA1c. Cardiovasc Diabetol. 2021;20(1):122. doi:10.1186/s12933-021-01315-5