Assessment of Remnant Lipoprotein Cholesterol and Oxidized Low density Lipoprotein Associated with Low-grade Inflammation in Coronary Heart Disease Subjects of Young South Indian Population.

Background: Coronary heart disease (CHD) is a major disease entity responsible for significant mortality and morbidity in the Indian population. The prevalence of CHD is increasing day by day in India. The hardening of arteries is linked to oxidative variations in low-density lipoproteins (LDLs). Modification of LDL to oxidized LDL (ox-LDL) is a crucial step in the oxidation hypothesis of atherogenesis. Oxidized LDL and remnant lipoprotein cholesterol (RLP-C) stimulate the immune and inflammatory reactions and promote atherosclerosis. Because of its lesser size along with high cholesterol content, and increased residence period in blood the remnant lipoproteins are highly atherogenic. Remnant lipoproteins transport more cholesterol to macrophages compared to LDL particles. Remnant lipoproteins enter into the arterial wall easily and are taken up directly by macrophages. This leads to the formation of foam cells, thus initiating the lipid-laden plaque. High sensitive C-reactive protein acts as a nonspecific inflammatory marker. Oxidized LDL along with RLP-C and high-sensitivity C-reactive protein (hs-CRP) play crucial role in progression of CHD.

Aim Of The Study: The aim of the study is to assess ox-LDL and RLP-C associated with hs-CRP as potential biomarkers in the development of CHD.

Materials And Methods: This cross-sectional study was conducted in Sri Ramaswamy Memorial Medical College Hospital and Research Centre on subjects appearing for master health check-up and medicine. This cross-sectional study was conducted on 273 subjects who were age and sex match in the age group of ≤45 years. 91 Non-Diabetic subjects with CHD, 91 Diabetic subjects with CHD, and 91 normal healthy subjects were selected as control. After overnight fasting, body fluid samples were collected for analysis for lipid profile, ox-LDL, and hs-CRP. Oxidized LDL and hs-CRP were measured by enzyme-linked immunosorbent assay (ELISA) method and lipid profile was measured using Auto Analyser AU480. Statistical analysis was done using Student's t-test and Pearson's correlation analysis for the comparison between two groups.

Results: The mean level of ox-LDL, RLP-C, and hs-CRP was significantly elevated in CHD group. A significantly positive correlation was observed between plasma ox-LDL, RLP-C, and hs-CRP.

Conclusion: These results suggest that the link between high ox-LDL, RLP-C, and hs-CRP levels might be interrelated to atherogenesis in subjects with CHD. In addition to conventional parameters, ox-LDL, RLP-C, and hs-CRP can prove to be a valuable tool in risk assessment of CHD. Journal of the Association of Physicians of India (2022): 10.5005/japi-11001-0009.