Coronary artery calcification, carotid intima-media thickness and cardiac dysfunction in young adults with type 2 diabetes mellitus

Abstract

Aims: Cardiovascular diseases (CVD) are the major causes of mortality in patients with type 2 diabetes mellitus (T2DM). There is paucity of information on prevalence of subclinical atherosclerosis and cardiac dysfunction in young adults with T2DM. This study aimed to assess the prevalence of subclinical atherosclerosis and cardiac dysfunction in young adults with T2DM, asymptomatic for CVD.

Methods: Sixty-two patients with T2DM, age between 30 and 50 years were evaluated for coronary artery calcium (CAC) score, carotid intima-media thickness (CIMT) and flow-mediated dilatation (FMD) at the brachial artery. All were subjected to 2D-color Doppler echocardiography, electrocardiography and testing for serum N-terminal pro-brain natriuretic peptide (NT-proBNP) and high-sensitivity C-reactive protein (hsCRP). The results were compared with those in 60 age, sex and BMI-matched healthy controls.

Results: Prevalence of a positive CAC score was comparable among subjects with and without T2DM (14.5% vs 11.7%). Patients with T2DM had a significantly higher CIMT (0.54 ± 0.15 vs 0.49 ± 0.10 mm, p = 0.01), left ventricular (LV) mass (170 ± 36 vs 147 ± 23 g, p < 0.001), heart rate (83 ± 13 vs 74 ± 11, p < 0.001) and QTc interval (402 ± 20 vs 382 ± 21 ms, p < 0.001) compared to controls. FMD was lower in patients with T2DM compared to controls (9.1 ± 4.4% vs 10.7 ± 3.9%, p = 0.04). There was a higher prevalence of LV hypertrophy (37% vs 7%, p < 0.001) and diastolic dysfunction (7% vs 0) in patients with T2DM compared to controls. None of the participants had systolic dysfunction. Hypertension (42 vs 7%, p < 0.001) and metabolic syndrome (76 vs 35%, p < 0.001) were more prevalent in the patient group. In the multivariate analysis, age was the lone predictor of CIMT and FMD; while T2DM and male gender were the independent predictors of LV mass.

Conclusions: Young adults with T2DM, asymptomatic for CVD had a higher prevalence of CVD risk factors, LV hypertrophy and diastolic dysfunction. A higher CIMT and LV mass, and a lower FMD were noted in patients with T2DM. CAC score was comparable between the groups and thus may not be a useful tool for assessment of subclinical atherosclerosis in this cohort, where CIMT and FMD may be more appropriate.

Keywords: Carotid intima-media thickness; Coronary artery calcium; Echocardiography; Flow-mediated dilatation; Type 2 diabetes mellitus; Young diabetes.