Association of Leptin and Leukocyte Telomere Length with Anthropometric Markers of Obesity in Indian Adults: A Cross-sectional Study

Abstract Background: Obesity is a major risk factor for metabolic and age-related diseases, yet its association with biological ageing remains unclear. Telomere length is a recognized biomarker of cellular ageing, and adipokines, such as leptin, may play a role in telomere attrition. This study investigates the relationship between leukocyte telomere length (LTL), serum leptin levels, and anthropometric markers of obesity in an adult Indian population. Materials and Methods: A cross-sectional study was conducted among 90 adults, stratified equally into normal-weight, overweight, and obese groups based on the World Health Organization’s Asia-Pacific body mass index (BMI) criteria. Anthropometric parameters were recorded. LTL was measured using quantitative polymerase chain reaction, and serum leptin levels were determined by enzyme-linked immunosorbent assay. Correlation analyses were performed using Spearman’s test. Results: LTL showed significant inverse correlations with BMI ( r = −0.205, P = 0.047), hip circumference ( r = −0.269, P = 0.010), and neck circumference ( r = −0.227, P = 0.032). A paradoxical positive correlation was observed with waist-hip ratio (WHR) ( r = 0.233, P = 0.027). Serum leptin levels showed no significant correlation with LTL or anthropometric variables in the overall cohort. However, participants with normal BMI but elevated WHR exhibited significantly higher leptin levels (8.29 ± 12.51 ng/mL), suggesting leptin resistance. Conclusion: LTL was associated with general adiposity markers, but its relationship with WHR was paradoxical and requires cautious interpretation. Central adiposity, identified by high WHR, was a marker of metabolic dysfunction (hyperleptinemia) independent of BMI. The dissociation between leptin and telomere length highlights the complex interplay between metabolic risk and cellular ageing in this population.