Assessment of Adiponectin and Leptin Levels in Diabetic Patients with Varying Stages of Nephropathy

Abstract

Background:
Diabetic nephropathy (DN) is one of the most serious microvascular complications of diabetes mellitus, representing a leading cause of end-stage renal disease (ESRD) worldwide. Among the multiple pathogenic mechanisms implicated, adipocytokines particularly adiponectin and leptin—play a crucial role in glucose homeostasis, insulin sensitivity, inflammation, and renal function regulation. Altered levels of these adipokines have been observed in diabetic patients, yet their correlation with the progression of nephropathy remains an area of ongoing investigation. Understanding these associations could help in early detection and risk stratification of DN.

Objective:
To assess serum levels of adiponectin and leptin in diabetic patients with varying stages of nephropathy and to determine their relationship with renal function indicators, including urinary albumin excretion and estimated glomerular filtration rate (eGFR).

Methodology:
A cross-sectional analytical study was conducted on 150 patients with type 2 diabetes mellitus at Hameed Latif Hospital Lahore, stratified into three groups based on urinary albumin excretion: normoalbuminuria, microalbuminuria, and macroalbuminuria (50 patients in each group). Serum adiponectin and leptin levels were measured using enzyme-linked immunosorbent assay (ELISA). Renal function was evaluated using serum creatinine, eGFR, and urinary albumin-to-creatinine ratio (UACR). Statistical analysis was performed using ANOVA and Pearson’s correlation coefficient to assess differences and associations among variables, with p < 0.05 considered significant.

Results:
Adiponectin levels showed a significant decrease with the progression of nephropathy, while leptin levels exhibited a marked increase from normoalbuminuric to macroalbuminuric groups (p < 0.001). In patients with advanced nephropathy, serum leptin positively correlated with serum creatinine and UACR (r = 0.62 and r = 0.57, respectively), while adiponectin demonstrated a negative correlation with both parameters (r = –0.49 and r = –0.46, respectively). The adiponectin-to-leptin ratio declined progressively with increasing severity of nephropathy, indicating a potential role as an early biomarker of renal dysfunction in diabetes.

Conclusion:
The study highlights that decreased adiponectin and elevated leptin levels are closely associated with worsening renal function in diabetic nephropathy. These adipokines may serve as potential biomarkers for early detection and monitoring of nephropathy progression among diabetic patients.