Leptin Levels, Lipid Profiles, and Central Fat Distribution in Atherosclerosis: Implications for Cardiovascular Disease Risk

Mathangi R¹, Selvaraj J², Reji M³, Jaideep M⁴, Ponnulakshmi R⁵, Nalini D^4*, Samyuktha. P⁶, Pugazharasan⁶

Understanding leptin's role in atherosclerosis and its link with metabolic and anthropometric factors can aid in cardiovascular risk management.

Abstract

Background: Leptin, an adipocyte-derived hormone, is overexpressed in atherosclerotic lesions and implicated in promoting thrombosis and atherosclerosis through pro-inflammatory signaling. Despite its known role in obesity-related cardiovascular diseases (CVDs), the precise relationship between leptin levels and various metabolic and anthropometric factors in atherosclerosis remains underexplored. Methods: This study aimed to investigate the role of leptin in the pathogenesis of atherosclerosis by measuring serum leptin levels in atherosclerosis patients and analyzing their correlation with anthropometric variables (waist-to-hip ratio, body mass index) and biochemical parameters (lipids, glucose). Participants included both atherosclerosis patients and non-CVD controls. Serum leptin, glucose, triglycerides, cholesterol, HDL, and LDL levels were measured, and anthropometric measurements were taken. Results: Serum leptin levels were significantly higher in atherosclerosis patients compared to non-CVD controls across all weight categories: normal weight (23.1 ± 5.1 ng/mL vs. 5.7 ± 3.8 ng/mL, p < 0.0001), overweight (30.2 ± 3.7 ng/mL vs. 10.5 ± 4.2 ng/mL, p < 0.0001), and obese (42.8 ± 4.5 ng/mL vs. 29.3 ± 9.1 ng/mL, p < 0.0001). Leptin levels positively correlated with BMI (r = 0.57, p < 0.0001) and were higher in normal weight atherosclerosis patients than in overweight controls, indicating possible leptin resistance. Additionally, atherosclerosis subjects exhibited elevated serum glucose, triglycerides, cholesterol, HDL, and LDL levels compared to controls, with significant differences noted in overweight subjects. Both systolic and diastolic blood pressures were higher in overweight atherosclerosis patients. Waist-to-hip ratio positively correlated with triglycerides (r = 0.42, p = 0.0001) and VLDL (r = 0.45, p < 0.0001) in atherosclerosis patients. Conclusion: Elevated leptin levels in atherosclerosis patients, alongside increased triglycerides and altered lipid profiles, suggest a role for leptin in the pathogenesis of atherosclerosis and associated cardiovascular risk. The positive correlation between waist-to-hip ratio and lipid parameters underscores the significance of central fat distribution in cardiovascular health.

Keywords: leptin, atherosclerosis, triglycerides, central fat distribution, cardiovascular disease

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