Waist-hip ratio is an independent predictor of moderate-to-severe OSA in nonobese males: a cross-sectional study

BACKGROUND: Adiposity is a well-established risk factor for obstructive sleep apnea (OSA), but whether a combination of preferable anthropometric measurements may improve the accuracy of detecting OSA is unknown. This study aimed to explore the accuracies of the waist-hip ratio (WHR) in conjunction with the body mass index (BMI) when identifying the severity of OSA. DESIGN: A total of 2012 participants in the China-Japan Friendship Hospital from January 2018 to December 2019 underwent anthropometric measurements and an overnight home sleep test (HST). The 244 subjects who met the criteria for obstructive sleep apnea (apnea–hypopnea index (AHI) ≥ 5 events/hour) were divided into four groups: Group A (55 patients with WHR ≥ 0.9 and BMI ≥ 28 kg/m(2)); Group B (12 patients with WHR < 0.9 and BMI ≥ 28 kg/m(2)); Group C (69 patients with WHR ≥ 0.9 and BMI < 28 kg/m(2)); and group D (108 patients with WHR < 0.9 and BMI < 28 kg/m(2)). RESULTS: The AHI, apnea index (AI), hypopnea index (HI), and oxygen desaturation index (ODI) were significantly different among the 4 groups (p < 0.05). The WHR was positively correlated with AHI (r = 0.22, p < 0.001), AI (r = 0.270, p = 0.004), and ODI (r = 0.286, p = 0.0022) and negatively correlated with lowest oxygen pulse saturation (LSpO(2)) (r = 0.246, p = 0.008) only in nonobese patients. Moreover, the WHR was found to be a screening marker for moderate-to-severe OSA in Group D (p < 0.05). When used to identify severe OSA in Group D, the WHR cut-off point of 0.873 yielded a sensitivity of 65% and specificity of 56% (p < 0.05). CONCLUSION: In nonobese male OSA patients, WHR is a moderate screening marker for moderate-to-severe OSA and an independent risk factor for OSA severity. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12890-022-01886-3.