Visceral Fat Area by Abdominal Bioelectrical Impedance Analysis as a Risk of Obstructive Sleep Apnea: A Single-Clinic Retrospective Case Study

This is the first study to evaluate directly visceral fat area (VFA) using a visceral fat (VF) meter by the abdominal bioelectrical impedance analysis (A-BIA) method in obstructive sleep apnea (OSA) patients diagnosed with polysomnography (PSG). The purpose of this study is to clarify (1) whether VFA measurement using a VF meter by the A-BIA method is possible even in a private clinic without burdening patients and staff and (2) how much VFA affects OSA compared to body mass index (BMI). Even without a computed tomography scan, which is the gold standard for VFA measurement, a VF meter could analyze patients by the A-BIA method and easily measure VFA. Therefore, it could be used safely even in a private sleep clinic, with very little burden on the patients and the medical staff. We investigated the association between OSA and VFA in 133 OSA patients. Multiple regression analysis revealed that VFA (β = 0.28; P = 0.020) was a stronger coexisting factor for OSA than age, male gender, or BMI (β = 0.26; P = 0.032) in all OSA patients. In the OSA patients with VF accumulation, only VFA was a significant component of OSA severity (β = 0.36; P = 0.006). The A-BIA method instrument could become a useful device for the evaluation of VF accumulation in OSA patients in private sleep clinics. VF accumulation should be recognized as an important risk factor as well as a known risk factor for OSA.