Circulating Adipokines and Cortisol in Adults with Obesity: A Cross-Sectional Study from Baghdad

Abstract

Adipose tissue is a productive endocrine organ. It secretes many of bioactive proteins that control vascular biology, inflammatory tone, and insulin sensitivity. In obesity, its secretory profile changes in ways that significantly increase metabolic risk. There is still a dearth of population-specific statistics, especially from urban Middle Eastern environments. This cross-sectional study enrolled 120 adults in Baghdad — 60 with obesity (BMI ≥ 30 kg/m²) and 60 age- and sex-matched normal-weight controls — and measured serum concentrations of chemerin, visfatin, resistin, omentin-1, asprosin, and cortisol by validated ELISA. Group differences were assessed using the Mann–Whitney U test with rank-biserial effect-size quantification. Spearman correlations were computed with Bonferroni correction (α = 0.0017) applied across 30 simultaneous tests, and binary logistic regression combined with receiver operating characteristic (ROC) analysis evaluated the predictive and discriminatory value of each biomarker. Five biomarkers were significantly elevated in the obese group — chemerin, visfatin, resistin, asprosin, and cortisol (all p < 0.001) — while omentin-1 was markedly reduced. All six produced large to very large rank-biserial effect sizes (r_rb ≥0.50) and correlated significantly with BMI, waist circumference, and HOMA-IR after Bonferroni correction. Visfatin was the strongest independent predictor of obesity in logistic regression (OR = 3.12; 95% CI: 1.87–5.21; p < 0.001); chemerin, asprosin, and omentin-1 also retained significance. With an AUC of 0.91 (95% CI: 0.85–0.97; Youden's J = 0.75), a composite panel of these four biomarkers outperformed any single analyte. Targeted adipokine monitoring may significantly improve traditional metabolic risk assessment because the dysregulation pattern is coherent, internally consistent, and clinically interpretable.