Study of Serum Apelin and Insulin Resistance in Type 2 Diabetes Mellitus Patients With or Without Obesity

Introduction: Type 2 diabetes mellitus (T2DM) is a chronic disorder characterized by persistent hyperglycemia. Chronic hyperglycemia in diabetes mellitus can cause microvascular and macrovascular complications. Obesity is a major risk factor contributing to disease progression and complications of T2DM. Apelin is an adipokine having a compensatory role in reducing insulin resistance (IR) in morbidly obese individuals. This study was undertaken to find a correlation between Apelin, IR, and obesity. Methods: This case-control study included 180 participants, cases (n=90) having T2DM, and healthy controls (n=90). Further, the case and control groups were divided into group I (non-obese) and group II (obese) according to their body mass index (BMI) as per the Asia Pacific classification of BMI. Following obtaining consent, anthropometrical measurements and blood parameters like serum total lipid profile, fasting and postprandial glucose level, Apelin, and insulin were done, and results were analyzed statistically using Statistical Package for the Social Sciences (SPSS) version 21 (IBM Corp., Armonk, NY). Results: A significantly higher Apelin level was observed in diabetes patients with obesity (265.16±11.0 pg/mL) as compared to non-obese (206.44±83.0 pg/mL). A positive correlation between serum Apelin levels and BMI was found (r=0.367, p=0.003). Homeostasis Model Assessment of IR (HOMA-IR) is increased in obese patients in comparison to the control group. A significant positive correlation between BMI and HOMA-IR (r=0.429, p=0.001) and Apelin and IR (r=0.742, p=0.000) was found in this study. Conclusion: On the basis of the finding of this study, we may conclude that Apelin has a role in improving insulin sensitivity in T2DM. Larger and multicentric studies are further required to discover the therapeutic role of Apelin in T2DM.