MFR, SVR and ASVR as promising biomarkers in overweight and obese population with obstructive sleep apnea syndrome: insights from an observational study

BACKGROUND: Obesity is an important risk factor of obstructive sleep apnea syndrome (OSAS), but not all obese people can develop OSAS. The role of novel human body composition indices-muscle-to-fat ratio (MFR), skeletal muscle mass-to-visceral fat area ratio (SVR) and appendicular skeletal muscle mass-to-visceral fat area ratio (ASVR)-in OSAS remains largely unknown. The aim of this study is to investigate the associations of these indices to OSAS in overweight and obese adults. METHODS: Overweight or obese patients with complete human body composition and polysomnography data were included in this study. The data of physical examination, Epworth sleepiness scale and demographic information were retrospectively collected. Subjects were divided into two groups, named non-OSAS and OSAS. MFR, SVR and ASVR were compared between two groups. Logistic regression analysis, restricted cubic spline analysis and mediation analysis were conducted to evaluate the relationship between these indices and OSAS. Moreover, receiver operating characteristic (ROC) curves were drawn to evaluate these indices in OSAS diagnosis. RESULTS: A total of 192 overweight or obese patients were enrolled in this study, including 122 OSAS patients. Compared with non-OSAS patients, OSAS patients were older and exhibited higher frequency of male, smoking history and more comorbidities. MFR, SVR and ASVR were higher in OSAS group, especially in male OSAS patients. However, these indices were not independent risk factors to OSAS. Mediation analysis presented these indices might mediate the relationship between age and OSAS, but this effect was affected by sex. ROC curves showed these indices had high sensitivity and specificity in OSAS diagnosis in subjects with less symptoms. CONCLUSION: MFR, SVR and ASVR increased in male OSAS patients in overweight and obese adults. These indices might contribute to early recognizing OSAS patients with less symptoms, especially in primary care settings.