Prevalence of snoring and witnessed apnea in Taiwanese adults

Background: Sleep-disordered breathing (SDB) is a prevalent disorder that has a huge impact on the public. It has been proposed that Chinese populations have a higher incidence of SDB than Caucasians due to a narrow cranial base and flat mid-face structure. Few studies have investigated the prevalence of SDB in Taiwan. This study prospectively assesses the complaints of SDB and related conditions via telephone interviews with individual older than fifteen in Taiwan to calculate a possible prevalence. Methods: Computer-assisted telephone interviews were conducted from Oct. 25, 2006 to Nov. 6, 2006. Individuals aged over 15 years were interviewed. The number of successful interviews was calculated based on the population prior to the study. Demographic data and data for symptoms of SDB and medical conditions were obtained. Results: In total, 4,011 individuals, 1,634 males and 2,377 females, completed the interviews. The prevalence of snoring in these Taiwanese individuals was 51.9% [95% confidence interval (CI) 51.13%-52.67%], 60.8% (95% CI 58.67%-62.93%) in males and 42.5% (95% CI 40.26%-44.74%) in females. The prevalence of witnessed apnea during sleep was 2.6% (95% CI 2.1%-3.1%), 3.4% (95% CI 2.6%-4.2%) in males and 1.9% (95% CI 1.28%-2.52%) in females. The prevalence of snoring and witnessed apnea was significantly higher in males than in females (p < 0.05). Prevalence of hypertension, cardiovascular disease, diabetes mellitus, arthritis and backache was higher in those who snored or had witnessed apnea than those without these symptoms (p < 0.05). Conclusion: This study determined that 51.9% (95% CI 51.13%-52.67%) of Taiwanese snore and 2.6% (95% CI 2.1%-3.1%) have witnessed apnea. Those who snore or have witnessed apnea have a higher incidence of comorbidity with major medical diseases compared to those who do not snore or do not have witnessed apnea.