Background and Objectives: Type 2 diabetes mellitus is associated with the development of premature atherosclerosis and a higher cardiovascular morbidity and mortality. Diabetic dyslipidemia is believed to play an important role in the pathogenesis of accelerated atherosclerosis in this condition. It is being increasingly believed that atherosclerosis is a postprandial phenomenon as at least with respect to lipids, we are in the postprandial phase for most of the day. High postprandial triglycerides have shown a strong and independent association with CAD. Hence this study is being carried out to assess the characteristics of postprandial dyslipidaemia in types 2 diabetes mellitus in comparison with the fasting lipid levels in diabetics and controls.

Methodology: This was an observational study which included the patients admitted in Raja Muthiah Medical College Hospital, Chidambaram, Tamilnadu .The study included 50 patients with type 2 diabetes mellitus meeting the inclusion criteria and were compared with 50 age and sex matched healthy controls, fulfilling the inclusion and exclusion criteria.

Method of Collection of Data: Data for the proposed study was collected in a pretested proforma. Detailed history and physical examination of all the cases and controls was done. Fasting and Post prandial lipid levels were estimated in all the cases and controls. Blood was collected from patients after an overnight (12-hour) fast and six hour postprandial (after a standard meal) for lipid profile measurements.

Results: The majority of cases were in the age group of 61-70 years. All the cases in the fasting state had a raised triglyceride (mean 172.92±75.51mg/dL) level, raised VLDL-C (mean 37.76±20.01mg/dL) level, decreased HDL-C (mean 33.44±11.99mg/dL) level, normal total cholesterol (mean176.36±52.43mg/dL) level and normal LDL-C  (mean 101.16±38.17mg/dL) levels compared to the control group. In the post prandial state the diabetics had a significant increase in the post prandial triglyceride level (mean 232.52±105.08mg/dL), decrease in the HDL-C level (mean 30.96±11.15mg/dL) compared to the fasting state whereas in the control group there was no significant increase in the post prandial lipid levels compared to the fasting state.

Conclusion: The dyslipidemia of Type 2 DM is characterised mainly of raised triglyceride levels, raised VLDL-C Levels and decreased HDL-C levels. In the post prandial state there was significant hyper-triglyceridaemia and decreased HDL-C level in diabetics when compared to that of the controls.

Keywords: Dyslipidemia, atherosclerosis, hyper-triglyceridaemia, postprandial dyslipidemia.

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S.Pravin