Aims: The aim of the present study was to assess carotid intimal media thickness (IMT) in different grades of glucose intolerance and the metabolic syndrome (MS) in Asian Indians, a high-risk group for diabetes and coronary artery disease.
Methods: Subjects with normal glucose tolerance (NGT) (n = 1600), impaired glucose tolerance (IGT) (n = 330), newly diagnosed diabetes (NDD) (n = 330) and known diabetes (KD) (n = 1170) were recruited from the Chennai Urban Rural Epidemiology Study (CURES), an ongoing study on a representative population of Chennai (formerly Madras), in southern India. Assessment of carotid IMT was performed using high-resolution B-mode ultrasonography. MS was defined using modified adult treatment parel (ATP) III guidelines. Subjects with self-reported diabetes, hypertension and dyslipidaemia were excluded from the analysis on MS.
Results: Subjects with glucose intolerance had significantly higher mean carotid IMT values compared with subjects with normal glucose tolerance (NGT 0.69 +/- 0.12 mm, IGT 0.75 +/- 0.16 mm, NDD 0.79 +/- 0.19 mm and KD 0.87 +/- 0.24 mm, P < 0.001). Regression analysis showed that there was a linear increase in mean IMT values with increasing severity of glucose intolerance, even after adjusting for age and gender. Mean IMT values were higher in those with MS and increased with increase in number of metabolic abnormalities (subjects without any metabolic abnormality 0.66 +/- 0.12 mm, one abnormality 0.67 +/- 0.13 mm, two 0.70 +/- 0.12 mm, three 0.72 +/- 0.12 mm, four 0.77 +/- 0.15 mm, five 0.76 +/- 0.13 mm). Regression models showed MS to be associated with IMT, even after adjusting for age, gender and presence of diabetes (P = 0.021).
Conclusions: In Asian Indians, carotid IMT increases progressively with increasing severity of glucose intolerance and is also associated with the metabolic syndrome, independent of age, gender and presence of diabetes.