Predisposing factors of sleep-disordered breathing in Japanese male workers.

The aim of this study was to elucidate the usable predisposing factors of sleep-disordered breathing (SDB) in the workplace. A total of 353 male workers who complained of SDB related symptoms such as witnessed snoring, recurrent awakening from sleep, urination during the night, morning headache, and excessive daytime sleepiness were included in the analysis. We examined hyoid-mental distance (HMD), modified Mallampati score (MMS), and the narrowness of the pharynx with tonsillar hypertrophy as the predisposing physical findings of SDB. We used the number of 3% or more oxygen desaturation events per hour (ODI3) as the indicator of SDB. The mean values (S.D.) of all subjects were 44.3 (8.9) yr (19-66 yr) of age, and 25.9 (3.8) Kg/m(2) body mass index (BMI). A significant difference in ODI3 was found between the HMD classes, and also between the subjects with and without tonsillar hypertrophy. Mean ODI3 adjusted for age, BMI, and alcohol consumption on the day of monitoring was high in the group of short HMD and the group of tonsillar hypertrophy (+). For MMS, though ODI3 did not appear to be significantly different, mean ODI3 was high in the MMS-IV. In conclusion, short HMD and tonsillar hypertrophy are the important findings predicting SDB identified by pulse oximetry. These findings would be beneficial in the workplace for selection of subjects who should be encouraged to undergo pulse oximetry for detection of SDB.