In‐Hospital Mortality Among Patients With Type 2 Diabetes Mellitus and Acute Myocardial Infarction: Results From the National Inpatient Sample, 2000–2010

Abstract

Background Case‐fatality rates in acute myocardial infarction ( AMI ) have significantly decreased; however, the prevalence of diabetes mellitus ( DM ), a risk factor for AMI , has increased. The purposes of the present study were to assess the prevalence and clinical impact of DM among patients hospitalized with AMI and to estimate the impact of important clinical characteristics associated with in‐hospital mortality in patients with AMI and DM . Methods and Results We used the National Inpatient Sample to estimate trends in DM prevalence and in‐hospital mortality among 1.5 million patients with AMI from 2000 to 2010, using survey data‐analysis methods. Clinical characteristics associated with in‐hospital mortality were identified using multivariable logistic regression. There was a significant increase in DM prevalence among AMI patients (year 2000, 22.2%; year 2010, 29.6%, P trend <0.0001). AMI patients with DM tended to be older and female and to have more cardiovascular risk factors. However, age‐standardized mortality decreased significantly from 2000 (8.48%) to 2010 (4.95%) ( P trend <0.0001). DM remained independently associated with mortality (adjusted odds ratio 1.069, 95% CI 1.051 to 1.087; P <0.0001). The adverse impact of DM on in‐hospital mortality was unchanged over time. Decreased death risk over time was greatest among women and elderly patients. Among younger patients of both sexes, there was a leveling off of this decrease in more recent years. Conclusions Despite increasing DM prevalence and disease burden among AMI patients, in‐hospital mortality declined significantly from 2000 to 2010. The adverse impact of DM on mortality remained unchanged overall over time but was age and sex dependent.