Abstract
BACKGROUND: Obstructive sleep apnea (OSA) is a common disorder characterized by airway obstruction. Recent evidence suggests that insulin resistance (IR) may significantly impact sleep health. The triglyceride-glucose (TyG) index has emerged as a non-invasive marker of IR, potentially linked to OSA risk. However, existing studies often featured small sample sizes and limited analyses. This study aimed to evaluate the association between the TyG index and the risk and severity of OSA in the general population. METHODS: We conducted a cross-sectional, single-center, retrospective study involving 600 adult patients with complete sleep respiratory monitoring results at West China Hospital from December 2024 to May 2025. The TyG index was treated as the exposure variable, while the risk and severity of OSA were the outcome variables. The TyG index was calculated as follows: TyG = ln [fasting triglycerides (TG) (mg/dL) × fasting blood glucose (FBG) (mg/dL)/2]. To assess the relationship between the TyG index and OSA, we performed multivariate logistic regression, subgroup analyses, and receiver operating characteristic (ROC) curve analyses. RESULTS: Among the total population, 515 (85.8%) were diagnosed with OSA and 247 individuals (41.2%) had severe OSA. After adjusting for potential confounders including age, sex, smoking, alcohol consumption, antihypertensive drugs, hypoglycemic drugs and various biochemical markers, multivariate logistic regression revealed that a one-unit increase in the TyG index was associated with a 168.9% higher risk of OSA (P<0.001), while a one-standard deviation (SD) increase corresponded to a 99.9% higher risk (P<0.001). Additionally, participants in the high-TyG group had a 2.954-fold higher risk of OSA compared with those in the low-TyG group [95% confidence interval (CI): 1.634-5.341; P<0.001]. In the fully adjusted model, each one-unit and one SD increase in the TyG index was associated with a 47.5% (P=0.003) and 31.3% (P=0.003) increase, respectively, in the risk of severe OSA. Subgroup analyses demonstrated that the association between the TyG index and both OSA risk and severity remained significant across several subgroups (P<0.05). Sensitivity analyses excluding individuals with chronic kidney disease confirmed the robustness of these associations (P<0.05). Operating characteristic curves (ROC) analyses indicated that the TyG index was a moderate predictor of OSA risk [area under the curve (AUC): 0.704; 95% CI: 0.674-0.762; P<0.001] and a modest predictor of severe OSA (AUC: 0.573; 95% CI: 0.524-0.622; P<0.001). CONCLUSIONS: Elevated TyG index levels are significantly associated with increased risk and severity of OSA, highlighting the potential utility of the TyG index as an initial screening tool in the diagnostic pathway for OSA. Future research should involve larger, prospective, multicenter trials and external validation.