High event rate after a first percutaneous coronary intervention in patients with diabetes mellitus: results from the Swedish coronary angiography and angioplasty registry.

BACKGROUND: Patients with diabetes mellitus have reduced longevity after acute coronary syndromes and revascularization. However, knowledge of the long-term complication rates and patterns from an everyday life setting is lacking. METHODS AND
RESULTS: Consecutive patients undergoing percutaneous coronary intervention included in the Swedish Coronary Angiography Angioplasty Registry (SCAAR) between 2006 and 2010 and with no previous revascularization were prospectively followed up for combined cardiovascular events (first of all-cause mortality, myocardial infarction, stroke, and heart failure) until December 31, 2010. The mean follow-up period was 920 days (SD, 530 days). Differences in background and procedural characteristics were adjusted for in a multivariate Cox regression model. Of 58 891 patients, mean age 67 years, 19% had diabetes mellitus; 27% of them were on diet treatment, 33% on oral glucose lowering, and 40% on insulin treatment. At admission, cardiovascular risk factors, multiple coronary vessel, and left main stem disease were more frequent in patients with diabetes mellitus and their revascularization was less often complete. The adjusted risk for combined cardiovascular events was higher in patients on insulin (hazard ratio [95% confidence interval], 1.63 [1.55-1.72]), on oral treatment (1.23 [1.15-1.31]), and on diet alone (1.21 [1.12-1.29]) compared with patients without diabetes mellitus. Insulin-treated patients ran an increased risk of restenosis (1.54 [1.39-1.71]) and stent thrombosis (1.56 [1.25-1.96]).
CONCLUSIONS: The prognosis after a first percutaneous coronary intervention is more severe in patients with diabetes mellitus, in particular, in patients treated with insulin, with higher rates of mortality, cardiovascular events, and stent thrombosis over the following 5 years.