Inflammatory markers, insulin resistance and carotid intima-media thickness in North-Indian type 2 diabetic subjects.

OBJECTIVE: To study the interrelationship of the inflammation, insulin resistance and atherosclerosis in recently diagnosed type 2 diabetes.

METHODOLOGY: Eighty-one newly diagnosed type 2 diabetic patients were compared with 81 healthy age, sex and BMI matched controls. Plasma glucose and insulin (fasting and after 2 hours of 75 gm of oral glucose), lipids and serum levels of C-reactive protein (CRP), fibrinogen and Tumour Necrosis Factor (TNF)-alpha were measured. Carotid (Intima-Medial Thickness) IMT was measured using high "resolution B-Mode ultrasonography. Insulin resistance was calculated using HOMA-IR model. Electrocardiogram (ECG) and exercise ECG were recorded for the evidence of coronary heart disease (CHD).

RESULTS: Carotid IMT was significantly thicker in diabetic patients than in control group across the whole age range (p < 0.01). In merged group of diabetes, composite IMT was significantly correlated with LDL-cholesterol, fasting insulin, serum cholesterol, BMI and HOMA-IR (p < 0.01). After controlling for age and sex, all glycaemic parameters were correlated with IMT in both diabetic and control group. HOMA-IR, waist hip ratio, serum triglycerides, serum cholesterol, fasting serum insulin and CRP were significant predictor of IMT. Concentrations of inflammatory markers were significantly higher in diabetic patients than in control group. Serum levels of CRP (p < 0.05) were found to be higher in diabetic patients with CHD than without CHD. CRP was significantly correlated with IMT (r = 0.603, p < 0.01) in diabetic subjects with and without CHD after controlling for age and sex.

CONCLUSION: Inflammatory markers are associated with type 2 diabetes but only CRP is associated with development of accelerated atherosclerosis and subsequent CHD.