The BMI-stratified analysis (Supplementary Table 1) revealed significant differences in ESS, OSA indices (AI, HI, AHI), HbA1c, C-peptide, insulin, IGFBP4, and leptin levels in the obese group, consistent with obesity being an independent contributor to OSA severity and metabolic dysregulation. This evidence concerns the gene LEP and obstructive sleep apnea syndrome.