Serum Leptin-adiponectin Ratio in Patients With and Without Metabolic Syndrome: A Cross-sectional Study

Introduction: Metabolic Syndrome (MetS) is one of the most significant global public health concerns. Leptin, adiponectin, and the Leptin-adiponectin (LA) ratio have been shown to be informative biomarkers for obesity, Type 2 Diabetes Mellitus (T2DM), and Cardiovascular Diseases (CVD). Many contributing factors, such as Insulin Resistance (IR), adipose tissue dysfunction, chronic inflammation, and genetic factors, are proposed to be the aetiological factors of MetS. Leptin and adiponectin have opposite effects on IR, so the combined use of these adipokines may serve as a better biomarker in MetS. Aim: To determine serum leptin levels, adiponectin levels, and the LA ratio in patients with and without MetS. Materials and Methods: This cross-sectional study was conducted in the Department of Biochemistry and Medicine at the Regional Institute of Medical Sciences (RIMS), Imphal, Manipur, India, from January 2021 to October 2022. The study included 50 diagnosed cases of MetS and 50 individuals without MetS. Leptin, adiponectin, and parameters of MetS {Body Mass Index (BMI), weight, Waist Circumference (WC), skinfold thickness, High -density Lipoprotein (HDL), Triglycerides (TG), and Blood Pressure (BP)} were assessed in the study. The data were statistically analysed using Independent Sample t -test and Pearson's correlation test. Results: There were 23 males and 27 females in the study group. The mean age was found to be 61.10 +/- 12.52 years in cases and 57.08 +/- 10.67 years in controls. Leptin levels were significantly higher in cases (26.58 +/- 14.6 ng/mL) compared to controls (12.99 +/- 8.59 ng/mL). However, adiponectin levels were significantly decreased in cases (7.16 +/- 4.19 pg/mL) compared to controls (12.18 +/- 9.4 pg/mL). The LA ratio was found to be higher in cases (5.38 +/- 4.71 ng/pg) than in the controls (1.84 +/- 1.99 ng/ pg). Multiple linear regression analysis demonstrated that the LA ratio was strongly associated with MetS among Leptin, Adiponectin, and the LA ratio (p<0.05). Conclusion: Metabolic syndrome was strongly associated with an increased LA ratio, leptin, and decreased adiponectin levels. The LA ratio can better discriminate the risk of MetS than leptin and adiponectin alone and may be used as a sensitive clinical surrogate biomarker of MetS.