Non-linear association of the metabolic score for insulin resistance with obstructive sleep apnea: a cross-sectional study from NHANES 2015–2018 - Cai, Zhimao; Li, Jiachen; Peng, Hui; Ye, Ye; Chen, Sixia; Zeng, Lingli; Lin, Jiashuang; Chen, Weifeng (Frontiers in Nutrition, 2025)