Associations of urinary NGAL with body mass index and waist-to-hip ratio in obesity-related kidney injury

The global prevalence of obesity has increased markedly, contributing to morbidities such as cardiovascular disease, type 2 diabetes, and obesity-related kidney disease. Chronic kidney disease (CKD) associated with obesity often progresses silently, making early diagnosis challenging. Traditional markers like the albumin-to-creatinine ratio (ACR) have limitations, highlighting the need for more sensitive biomarkers. Urinary neutrophil gelatinase-associated lipocalin (uNGAL) has emerged as a promising indicator of early renal injury. This study evaluated the uNGAL levels in 90 adult women stratified by body mass index (BMI) and waist-to-hip ratio (WHR) to assess their potential as a biomarker for obesity-associated kidney damage. Anthropometric measurements, including weight, height, waist circumference, and hip circumference, were obtained. Urine samples were analyzed for uNGAL using ELISA. Comparative and correlation analyses explored the associations between uNGAL and anthropometric variables. The results showed significantly higher uNGAL levels in obese participants and those classified as moderate- or high-risk by WHR compared to those in the controls (p < 0.05). Within the obese group, uNGAL correlated positively with BMI (r = 0.60) and weight (r = 0.52), while in the high-risk WHR group, positive correlations were found with weight (r = 0.54) and hip circumference (r = 0.50). These findings suggest that uNGAL may serve as an early, non-invasive biomarker for detecting subclinical kidney stress in women with obesity, particularly those with central adiposity.