A Community Study of Sleep-Disordered Breathing in Middle-aged Chinese Men in Hong Kong

Sleep-disordered breathing (SDB) in Asianpopulations is being increasingly recognized. This study investigatedthe prevalence of SDB in Chinese middle-aged office-based male workersin Hong Kong. Sleep questionnaires weredistributed to 1,542 men (age range, 30 to 60 years), and 784questionnaires were returned. Subsequently, full polysomnographic (PSG)examinations were conducted in 153 questionnaire respondents. Subjectswith an apnea-hypopnea index (AHI) ≥ 5 were recalled for clinicalassessment. Questionnaire respondents weresimilar in age and body mass index (BMI) to the general community inthe target age range and gender. Habitual snoring was reported by 23% of this cohort and was associated with excessive daytime sleepiness(EDS), hypertension, witnessed abnormal breathing pattern, BMI, and legmovements during sleep. Allowing for subject bias in undergoing PSG, the estimated prevalence of SDB and obstructive sleep apnea syndrome(OSAS) (defined as SDB in the presence of EDS) at various AHI cutoffthreshold values was 8.8% and 4.1% (AHI ≥ 5), 6.3% and 3.2% (AHI≥10), and 5.3% and 3.1% (AHI ≥ 15). Multiple stepwise logisticregression analysis identified BMI, habitual snoring, time taken tofall asleep, and age as predictors of SDB at AHI ≥ 5. Analysis ofanthropometric parameters indicated that the relative risk of OSASattributable to obesity was less than in white subjects. This community-based study of sleep apnea amongmiddle-aged men in Hong Kong using full PSG demonstrated an estimatedprevalence of OSAS (AHI ≥ 5 and EDS) at 4.1%. Increasing BMI and agewere associated with SDB, although factors other than adiposity mayalso have an important pathogenic role in OSA in Chinesesubjects.