Empirical Investigation of the Relationship Between Insulin Resistance and Inflammatory Biomarkers in Obese Adults in Lagos Metropolis

Insulin resistance and chronic low-grade inflammation are mechanistically intertwined in the pathogenesis of metabolic syndrome and type 2 diabetes, yet empirical data characterising this relationship in West African obese populations remain underrepresented in the literature. This study investigated the association between insulin resistance indices and selected inflammatory biomarkers in obese adults in Lagos Metropolis, South West Nigeria. A cross-sectional analytical design was employed, recruiting 120 obese adults aged 25 to 55 years from three tertiary hospital clinics. Insulin resistance was assessed using the homeostatic model assessment for insulin resistance, calculated from fasting insulin and glucose levels. Inflammatory biomarkers measured included high-sensitivity C-reactive protein, interleukin-6, and tumour necrosis factor-alpha, assayed by enzyme-linked immunosorbent assay. Anthropometric, dietary, and physical activity data were collected as covariates. Multiple regression and Spearman correlation were applied. Results showed significant positive correlations between homeostatic model assessment for insulin resistance scores and all three inflammatory markers. Interleukin-6 was the strongest independent predictor of insulin resistance after adjusting for confounders. Central adiposity as measured by waist circumference further amplified the relationship. The study fills a gap by quantifying inflammation-insulin resistance coupling specifically in a Nigerian urban obese cohort and recommends anti-inflammatory dietary strategies and metabolic screening as dual intervention targets. Keywords: insulin resistance, inflammation, obesity, interleukin-6, Lagos.