EVALUATING DIAGNOSTIC ACCURACY OF SERUM ADIPONECTIN AND LEPTIN IN PREDICTING INSULIN RESISTANCE AMONG TYPE 2 DIABETICS

Abstract

Background: Insulin resistance (IR) is a key metabolic defect in type 2 diabetes mellitus (T2DM), often preceding and aggravating hyperglycemia. The early identification of IR can significantly improve clinical outcomes. Adiponectin and leptin, two adipose-derived hormones, have been implicated in insulin sensitivity regulation, yet their diagnostic value in routine practice remains under-evaluated.

Objective: To determine the diagnostic accuracy of serum adiponectin and leptin levels for identifying insulin resistance in patients with T2DM.

Methods: This cross-sectional study enrolled 120 adult patients with confirmed T2DM, aged between 30 and 65 years, at a tertiary care hospital between January and August 2024. After overnight fasting, blood samples were collected to measure glucose, insulin, adiponectin, and leptin levels. Insulin resistance was assessed using the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR), with a cutoff value ≥2.5. Based on this, patients were classified into insulin-resistant (n=72) and non-resistant (n=48) groups. Independent samples t-test was used to compare mean biomarker levels between groups, while Pearson’s correlation was applied to assess associations with HOMA-IR.

Results: Mean adiponectin levels were significantly lower in insulin-resistant patients (5.6 ± 1.4 µg/mL) than in non-resistant patients (9.2 ± 2.1 µg/mL, p < 0.001, t = 8.92). Conversely, leptin levels were markedly higher in the insulin-resistant group (19.7 ± 3.8 ng/mL) compared to the non-resistant group (12.4 ± 2.9 ng/mL, p < 0.001, t = 10.15). Adiponectin showed a strong negative correlation with HOMA-IR (r = –0.62, p < 0.01), whereas leptin showed a moderate positive correlation (r = 0.57, p < 0.01).

Conclusion: Adiponectin and leptin levels differ significantly between insulin-resistant and non-resistant T2DM patients. Their evaluation may serve as a practical, non-invasive strategy to aid in the early identification of insulin resistance and guide personalized diabetic care.