TNF-α as a Predictor of Renal Involvement in Sedentary Obese Individuals
Author(s): Abdur Rahaman, Muhammad Nazrul Islam, A.H. Hamid Ahmed, Omar faroque, Kabir Hossain, Bedar Uddin, Bayejid Hossain, Nourin sultana
Background: Obesity-related renal dysfunction is a growing health concern, with TNF-α playing a crucial role in inflammation and renal pathology. TNF-α, a pro-inflammatory cytokine mainly produced by adipose tissue, is crucial in driving inflammation and kidney damage associated with obesity. This study aimed to evaluate TNF-α as a predictor of renal involvement in sedentary obese individuals without diabetes, hypertension, or hypothyroidism.
Methods: A cross-sectional observational research was undertaken at the Department of Nephrology, BSMMU, Dhaka. The study period ranged from February 2023 to August 2024. The study population consisted of 67 sedentary obese individuals, according to specific inclusion and exclusion criteria. The sampling method used was purposive sampling. Data were collected using a pre-tested questionnaire through patient history, clinical examination, and laboratory findings. Serum TNF-α levels were measured using the DRG Adiponectin ELISA Kit, which operates on the sandwich principle. Renal involvement was assessed by measuring the urinary albumin-to-creatinine ratio (uACR) and calculating the estimated glomerular filtration rate (eGFR) through the MDRD formula. Correlation analysis and ROC curve analysis were conducted to assess the predictive ability of TNF-α for microalbuminuria.
Results: The participants in the study had an average age of 35.88 ± 8.34 years, who were predominantly male (55.2%), with a significant portion being students (34.3%). Most participants exhibited obesity, with a mean BMI of 34.84 ± 3.47 kg/m², and more than 95% had central obesity. Laboratory results indicated normal glycemic control, with a mean fasting blood sugar of 4.93 ± 0.31 mmol/L and HbA1c of 5.06 ± 0.27%. However, 86.6% of participants had low HDL levels, and a significant number had elevated triglycerides and LDL levels.At enrollment, 8 participants (11.9%) had elevated urinary ACR. After excluding cases of transient microalbuminuria, 7 participants (10.4%) were confirmed to have microalbuminuria, resulting in an overall renal involvement rate of 10.4%. Participants with microalbuminuria exhibited significantly elevated serum TNF-α levels (136.49 ± 26.49 pg/ml, p<0.001). Serum TNF-α levels showed a weak positive correlation with BMI, LDL, and urinary ACR. A cut-off value of ≥137.65 pg/ml for TNF-α was identified as a significant predictor of microalbuminuria, demonstrating high sensitivity and specificity.
Conclusion: TNF-α levels demonstrated strong predictive power for early renal involvement, serving as a reliable biomarker for early renal dysfunction in sedentary obese individuals and enabling timely intervention to prevent CKD progression.