Correlation between METS-IR index and obstructive sleep apnea in non- diabetic adults: evidence from NHANES 2001–2018

Background: Insulin resistance (IR) is strongly associated with obstructive sleep apnea (OSA). Whereas, few studies have focused on the potential correlation between the Metabolic Score for Insulin Resistance (METS-IR), a novel non-insulin-dependent IR index, and OSA. Methods: Subjects from the National Health and Nutrition Examination Survey (NHANES) spanning 2005-2008 and 2015-2018 were recruited. The potential relationship between METS-IR and other IR indices with OSA was explored through three logistic regression analysis models and restricted cubic spline (RCS) curves. Receiver operating characteristic (ROC) curves were used to assess the diagnostic value of these indicators for OSA. On the basis of age, sex, race, body mass index (BMI), hypertension, and cardiovascular disease (CVD), subgroup analyses were conducted to test the robustness of the METS-IR and OSA relationship. Results: In all of 6,633 non-diabetic participants were enrolled, with an OSA prevalence of 28.40%. After adjusting for potential confounders, METS-IR, triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, triglyceride glucose Index (TyG), and homeostatic model assessment of insulin resistance (HOMA-IR) indices showed positive associations with OSA prevalence. In the highest tertile of METS-IR, TG/HDL-C, TyG index, and HOMA-IR indices, OSA prevalence was 3.22-fold, 1.42-fold, 1.45-fold, and 1.51-fold higher, respectively, compared to the lowest tertile (METS-IR: OR = 3.22, 95% CI: 2.67, 3.89, P < 0.0001; TG/HDL-C: OR = 1.42, 95% CI: 1.15, 1.76, P =0.002; TyG index: OR = 1.45, 95% CI: 1.18, 1.78, P <0.001; HOMA-IR: OR = 1.51, 95% CI: 1.24, 1.85, P <0.001). ROC analysis revealed that METS-IR had the highest diagnostic accuracy for OSA (AUC = 0.65). The relationship between METS-IR and OSA did not show significant interaction across all subgroups (P for interaction > 0.05). Conclusion: Compared with HOMA-IR, TG/HDL-C and TyG, METS-IR index was positively correlated with OSA prevalence and had superior diagnostic accuracy.