Assessment of Remnant Lipoprotein Cholesterol (RLP-C) Levels and its Correlation with Carotid Intima Media Thickness in Insulin Resistant Type 2 Diabetes Mellitus Patients BC29-BC31
Dr. Gnanasambandam Subramaniyam,
No 7, 2nd Street, Karpagam Avenue, RA Puram-600028, Chennai, Tamil Nadu, India.
Introduction: Remnant lipoproteins are Triglyceride (TG) rich lipoproteins products of partially metabolised chylomicrons and Very Low Density Lipoproteins (VLDL). Remnant Lipoprotein Cholesterol (RLP-C) levels are related to the risk of ischaemic heart disease. It has been hypothesized that Carotid Intima Media Thickness (CIMT) measurements could aid in the prediction of Cardiovascular Disease (CVD).
Aim: To evaluate the levels of RLP-C in Insulin Resistant (IR) Type-2 Diabetes Mellitus (T2DM) patients and correlate the levels of RLP-C with CIMT, IR, TG and High Density Lipoprotein (HDL).
Materials and Methods: The present cross-sectional study was conducted in the Department of Internal Medicine, SRM Medical College and Research Centre, Tamil Nadu, India. A total of 80 (aged 30 to 65 years) T2DM, men and women, aged 30-65 years, were included in the study. Serum lipids (Total Cholesterol (TC), TG, HDL-C and LDL-C), and serum insulin were measured. Insulin Resistance (IR) was estimated by the Homeostatic Model Assessment-Insulin Resistance (HOMA-IR). Based on HOMA-IR values, the individuals with HOMA-IR >2.5 were categorised as IR and HOMA-IR<2.5 as Insulin sensitive. RLP-C was calculated by using the formula: RLP-C=TC-(HDL-C+LDL-C). CIMT was measured in patients who had IR by using B Mode Ultrasonography (USG). Statistical analysis was done using Student’s t-test and Pearson correlation analysis.
Results: Among the insulin resistant diabetic patients, a positive correlation was observed between IR and serum TG (r=0.0448). In these subjects, RLP-C was positively correlated with serum TG (r=0.5191) and negatively correlated with HDL-C (r=-0.0542). A positive correlation was also observed between RLP-C and CIMT (r=0.513) in these patients with IR.
Conclusion: Type 2 diabetic patients with IR are characterised by high RLP-C and TG levels and low HDL-C levels. Estimation of RLP-C may help to identify individuals at high risk of atherosclerosis. The calculation of RLP-C can be easily done from the already existing conventional lipid profile at no additional cost.