Impact of diabetes on survival in patients with ST-segment elevation myocardial infarction treated by primary angioplasty: insights from the POLISH STEMI registry.

Background: It has been shown that, among patients with ST-segment elevation myocardial infarction (STEMI), diabetes is associated with a significantly higher mortality. The aim of this study was to investigate in a large cohort of patients the impact of diabetes on mortality in a large cohort of patients with STEMI treated with primary angioplasty.

Methods: Our population is represented by consecutive patients with STEMI treated by primary angioplasty and enrolled in the POLISH registry in 2003. All clinical, angiographic, and follow-up data were prospectively collected. Diagnosis of diabetes was based on history of diabetes at admission.

Results: Among 7193 patients, 877 (12.2%) had diabetes at admission. Diabetes was associated with more advanced age (p<0.0001), higher prevalence of female gender (p<0.0001), hyperlipidemia (p<0.0001), shock at presentation (p<0.0001), renal failure (p<0.0001), previous myocardial infarction (p<0.0001), more often treated after 6h from symptom onset (p<0.0001). Diabetes was associated with more extensive coronary artery disease (p<0.0001), less often treated with stenting (p<0.0001). Diabetes was significantly associated with impaired epicardial reperfusion (TIMI 0-2: OR [95% CI]=1.81 [1.5-2.18], p<0.0001), that persisted after correction for baseline confounding factors (OR [95% CI]=1.33 [1.075-1.64], p=0.009). At a mean follow-up of 524+/-194 days, diabetes was associated with higher mortality (unadjusted cumulative mortality: 23.5% vs. 12.6%, unadjusted HR=1.95 [1.66-2.3], p<0.0001), that persisted after correction for confounding factors (adjusted cumulative mortality: 13.3% vs. 10.7%, adjusted HR=1.23 [1.04-1.46], p=0.013).

Conclusions: This study shows that among STEMI treated by primary angioplasty diabetes is independently associated with impaired epicardial reperfusion and higher mortality.