To Örebro University

Background and aims: Patients with diabetes mellitus have a worse prognosis after acute coronary syndromes than patients without diabetes. Outcomes in patients with diabetes after ST-segment elevation myocar-dial infarction (STEMI) in the era of modern interventional treatment and antiplatelet therapy are less well studied. The aim is to characterise outcomes and complications in a contemporary population with diabetes and STEMI undergoing primary percutaneous coronary intervention (PCI).

Materials and methods: In the registry-based randomised Thrombus Aspiration in ST-Elevation myocardial infarction in Scandinavia (TASTE) trial, 7244 patients with STEMI were randomised to undergo manual thrombus aspiration followed by PCI or to undergo PCI alone. Thrombus aspiration did not affect mortality at one year in the 1005 patients (13.9%) with diabetes [Hazard ratio (HR) 1.04; CI 0.69-1.58,p=0.839]. Therefore, all patients with diabetes, irrespective ofrandomisation in TASTE, were studied as one cohort. All patients were followed for incidence of all-cause mortality, myocardial infarction or stent thrombosis until one year after index event. HRs were calculated using a Cox proportional hazard regression model adjusted for comorbidities.

Results: Patients with diabetes were older (mean age 67.6 vs 66.0 years, p<0.001), more often had a previous myocardial infarction (19.9 vs 10.3%, p<0.001) and undergone previous PCI (17.3 vs 8.4%, p<0.001). Thrombus grade did not differ between patients with and without diabetes (Grade 0 to Grade 5, p=0.909) and neither did the type of affected coronary vessel. Pharmacological cardiovascular treatment did not differ between groups, but the use of drug eluting stents was higher in patients with diabetes (59.0 vs 48.4%, p<0.001). After adjustment for comorbidities, diabetes independently increased the risk for mortality (HR 1.57; CI 1.23-2.00, p<0.001), but was not an independent risk factor for future myocardial infarction or stent thrombosis.

Conclusion: Diabetes remained an adverse prognostic risk factor in this contemporary setting, resulting in increased one-year mortality in a large cohort of patients with STEMI treated with PCI. This was not influenced by thrombus aspiration and not explained by a higher thrombus burden or differences in cardiovascular medical therapy compared to patients without diabetes.