Serum Adiponectin, Leptin, and the Adiponectin-to-Leptin Ratio as Predictors of Metabolic Syndrome in Ibadan

The adiponectin-to-leptin ratio has been proposed as a combined adipokine index that more sensitively captures metabolic dysfunction than either adipokine measured in isolation. This study evaluates serum adiponectin, leptin, and the adiponectin-to-leptin ratio as predictors of metabolic syndrome in adults attending a health screening clinic in Ibadan, South West Nigeria. A cross-sectional analytical design was employed, recruiting 250 adults aged 30 to 60 years from a community health fair. Metabolic syndrome was defined using harmonised IDF/NHLBI criteria. Adipokines were measured by ELISA, and standard metabolic parameters including lipid profile, fasting glucose, blood pressure, and waist circumference were also obtained. Receiver operating characteristic analysis determined the optimal adiponectin-to-leptin ratio threshold for metabolic syndrome diagnosis. The study examines whether the combined ratio outperforms waist circumference and conventional lipid indices in metabolic syndrome prediction. Sex-stratified analyses are presented given known adipokine differences between males and females. Findings will contribute to the biochemical understanding of adipose dysfunction in metabolic syndrome in South West Nigeria. Keywords: adiponectin, leptin, adiponectin-to-leptin ratio, metabolic syndrome, Ibadan.