Relationship between carotid atherosclerosis and coronary artery calcification in asymptomatic diabetic patients: A prospective multicenter study.

BACKGROUND: The value of screening sub-clinical atherosclerosis in asymptomatic patients with type 2 diabetes mellitus (T2DM) remains controversial.

HYPOTHESIS: An integrated model incorporating carotid intima-media thickness (CIMT) and carotid plaque with traditional risk factors can be used to predict prevalence and severity of coronary artery calcification in asymptomatic T2DM patients.

METHODS: A cohort of 262 asymptomatic T2DM patients were prospectively studied with carotid ultrasound to evaluate CIMT and carotid plaque and also a computed tomography coronary artery calcium (CT-CAC) scan.

RESULTS: Carotid plaque was detected in 124 (47%) patients and mean CIMT was 0.75±0.14 mm. Two hundred (76%) patients had a CAC score >0, of whom 57 (22%) had severe coronary atherosclerosis (>400 Au). In this group, carotid plaque was present in 40 (70%) patients (p<0.001). Univariable analysis revealed significant associations between non-zero CAC score and age (p<0.001), hypertension (p=0.01), gender (p=0.003) and duration of diabetes (p=0.004). Carotid plaque and mean CIMT were also significantly associated with non-zero CAC score (odds ratios [95% CI], 3.12 [1.66 -5.85] and 2.98 [0.24 -7.17], respectively). After adjusting for traditional risk factors, carotid plaque continued to be predictive of non-zero CAC score (2.59 [1.17 -5.74]) and CIMT was borderline significant (p=0.05). When analysed with binary logistical regression, the prevalence of carotid plaque significantly predicted severe CAC burden (CAC >400 Au; 3.26 [2.05 -5.19]). Upper CIMT quartiles showed a similar association (2.55 [1.33 -4.87]).

CONCLUSION: Carotid plaque is more predictive of underlying silent coronary atherosclerosis prevalence, severity and extent in asymptomatic T2DM patients.