title: Different impacts of neck circumference and visceral obesity on the severity of obstructive sleep apnea syndrome.
abstract: Our aim was to investigate the significance of neck circumference (NC) on the presence and severity of obstructive sleep apnea (OSA) syndrome independent of visceral fat (VF) obesity. A total of 219 subjects with suspected OSA underwent a complete polysomnography (PSG) study, along with the measurement of NC, and total body fat (TF) and VF levels (VFLs) measured by bioelectrical impedance analysis. We proposed NC divided by height (NC/H) as the simple index for height-corrected NC in Japanese subjects. NC/H exhibited a significantly stronger correlation than NC per se with BMI (r = 0.781 vs. 0.675, P = 0.0178), TF (r = 0.531 vs. 0.156, P < 0.0001), and VF (r = 0.819 vs. 0.731, P = 0.0203), indicating that NC/H is a better indicator of visceral obesity than NC per se. Interestingly, despite the strong correlation between NC/H and VFL, VFL was significantly associated with the apnea-hypopnea index (AHI) ≥ 5, ≥ 15, and ≥ 30, but not with ≥ 40 or ≥ 50, whereas NC/H was significantly associated with higher AHI values, i.e., AHI ≥ 50 but not with lower AHI value. Furthermore, multiple regression analyses revealed that VFL and NC/H were independently associated with the square root of AHI (AHI(0.5)) levels in obese and nonobese patients, respectively. In conclusion, NC is associated with the severity of OSA independently of visceral obesity, especially in nonobese patients.
authors: Department of Internal Medicine, Minami-Osaka Hospital, Osaka, Japan.
authors: Yuji
authors: Y
authors: Kawaguchi
authors: Shinya
authors: S
authors: Fukumoto
authors: Masaaki
authors: M
authors: Inaba
authors: Hidenori
authors: H
authors: Koyama
authors: Tetsuo
authors: T
authors: Shoji
authors: Shigeichi
authors: S
authors: Shoji
authors: Yoshiki
authors: Y
authors: Nishizawa
mesh_terms: D000328:Adult; D001827:Body Height / Q000502:physiology*; D015992:Body Mass Index; D017097:Electric Impedance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009333:Neck / Q000033:anatomy & histology*; D056128:Obesity, Abdominal / Q000150:complications* / Q000453:epidemiology / Q000473:pathology; D017286:Polysomnography; D012307:Risk Factors; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology