Usefulness of Carotid Plaques as Predictors of Obstructive Coronary Artery Disease and Cardiovascular Events in Asymptomatic Individuals With Diabetes Mellitus

Carotid intima-media thickness (CIMT) measurement and carotid plaque detection by B-mode ultrasound are frequently used as surrogates to predict coronary artery disease (CAD). However, their systematic use in routine clinical management of asymptomatic patients with diabetes mellitus (DM) has not been studied. The aim of the study was to identify carotid parameters that predict cardiovascular events in patients with asymptomatic type 2 DM by evaluating the relation between carotid disease and CAD. This multicenter, observational, prospective study included 259 asymptomatic patients with type 2 DM followed-up for 34 months after measurement of CIMT and carotid plaque with carotid ultrasound, and CAD assessment with computed tomography coronary angiography. Statistically significant differences between patients with and without carotid plaque were found for coronary plaque >50% stenosis (59 vs 36, p = 0.02). Greater maximal CIMT was associated with an increased risk of coronary plaque >50% (odds ratio 1.21 [1.02, 1.44], p = 0.03) and >70% stenosis (odds ratio 1.23 [1.01, 1.50], p = 0.04) after adjusting for traditional risk factors. At 34-month follow-up, the occurrence of total major adverse cardiovascular event was estimated to be 7.1% (mean age 68 years, 6% male and 1.1% female) in the whole study population. The subgroup of patients with carotid plaque showed increased incidence of major adverse cardiovascular event compared with patients with no carotid plaque (p = 0.005). In conclusion, carotid plaque was a strong predictor of future cardiovascular events and may be a prognostic marker in asymptomatic patients with type 2 DM. Carotid plaque and maximal intima-media thickness were independently associated with obstructive CAD.