237 segments (45 patients) from the DIABETES I, II, and III trials were included. Intracoronary ultrasound from motorized pullbacks (0.5 mm/s) after index procedure and at 9-month angiographic follow-up was performed in the same coronary segment. Nontreated mild lesions (angiographic stenosis < 25 % ) with ≥0.5 mm plaque thickening and ≥5 mm of length assessed by intracoronary ultrasound were included. As different types of plaques may be encountered throughout a given coronary lesion, each study lesion was divided into 3 segments for serial quantitative and qualitative analyses. Statistical adjustment by multiple lesion segments per patient (generalized estimating equations method) was performed. A CTP was defined as any qualitative change in plaque type at follow-up. At 1-year follow-up, major adverse cardiac events – death, myocardial infarction and target vessel revascularization) – were recorded.
A CTP was observed in 48 lesions (20.2 % ) and occurred more frequently (52.1 % ) in mixed plaques. Independent predictors of CTP were glycated hemoglobin levels (odds ratio [OR] 1.2; 95 % confidence interval [CI] 1.01-1.5; P = .04); glycoprotein IIb-IIIa inhibitors (OR 0.3; 95 % CI 0.1-0.7; P = .004) and statin administration (OR 0.3; 95 % CI 0.1-0.8; P = .02). At 1-year follow-up CTP was associated with an increase in major adverse cardiac events rate (CTP 20.8 % vs non-CTP 13.8 % , P = .008; hazard ratio = 1.9, 95 % CI 1.3-1.9, P = .01).
Qualitative changes in mild stenosis documented by intracoronary ultrasound in type II diabetics are associated with suboptimal secondary prevention and may have clinical consequences.