Temporal trends in mortality of patients with diabetes mellitus suffering acute myocardial infarction: a comparison of over 3000 patients between 1995 and 2003

Abstract

Over the last decade, advances in treatment for patients sustaining an acute myocardial infarction (AMI) have reduced mortality rates. We aimed to assess whether patients with diabetes mellitus (DM) have derived similar benefits as patients without DM. We compared characteristics, management, and survival of patients with and without DM who sustained an AMI in 1995 (n = 1762) with a second group of patients who sustained an AMI in 2003 (n = 1642). All patients were followed up for 18 months or until death. Between 1995 and 2003 the prevalence of DM in AMI patients increased from 12.5 to 16.6% (P < 0.001). Involvement of cardiologists, provision of secondary prevention agents and early revascularization rates improved in both groups. Thirty-day mortality improved significantly in patients with and without DM [40% (P = 0.006) and 30% (P < 0.001) relative reductions, respectively]. Despite this, there was no significant change in mortality at 18 months in patients with DM when comparing 1995 and 2003 (absolute mortality 38.0 vs. 36.4%, P = 0.71). The interaction between DM and study period in predicting long-term mortality was highly significant (P = 0.008); this persisted after adjustment for baseline characteristics and treatment variables. Although early post-AMI mortality has fallen in patients with and without DM, these improvements were only maintained in the longer term in those without DM; more effective diabetes-related management strategies are required post-AMI.