Screening obstructive sleep apnea using clinical questionnaires and the triglyceride–glucose index: a cardiovascular risk–based approach

Obstructive sleep apnea (OSA) is highly prevalent among patients with cardiovascular (CV) risk factors, yet early detection in primary care remains difficult, particularly in individuals with subtle or absent symptoms, in whom screening questionnaires may have limited accuracy. This study aimed to evaluate the diagnostic performance of five validated questionnaires and the triglyceride-glucose (TyG) index, alone and in combination, for detecting moderate-to-severe OSA in primary care patients stratified by CV risk. In this prospective study, 189 adults aged 18-75 years with hypertension, type 2 diabetes, or dyslipidemia were consecutively recruited from a primary care center in Spain. Participants completed the Berlin, STOP, STOP-BANG, NoSAS, and BASH-GN questionnaires, and the TyG index was calculated from fasting glucose and triglyceride levels. OSA was assessed using home sleep apnea testing, with moderate-to-severe OSA defined as an apnea-hypopnea index (AHI) ≥ 15 events/h. CV risk was categorized using SCORE charts. Overall OSA prevalence was 57.7%, and 23.8% of participants had moderate-to-severe disease. Individually, questionnaires and TyG showed modest discrimination (AUC range 0.575-0.675). Diagnostic accuracy improved when strategies were tailored to CV risk: in low-to-moderate CV risk patients, TyG combined with the Berlin questionnaire achieved the best performance (AUC 0.740), whereas in high-to-very-high CV risk patients, the TyG plus STOP-BANG combination performed best (AUC 0.732). Notably, high-risk patients had more severe OSA but fewer typical symptoms, suggesting a "silent" phenotype. Integrating TyG with selected questionnaires may modestly enhance detection of clinically significant OSA in primary care, particularly when adapted to CV risk.