Insomnia: prevalence and its impact on excessive daytime sleepiness and psychological well-being in the adult Taiwanese population.

OBJECTIVES: This study examined the national age- and sex-specific prevalence rates of insomnia and excessive daytime sleepiness (EDS), the associations of insomnia symptoms with daytime consequences, and the impact of insomnia on EDS and psychological well-being.

METHODS: Data of 36,743 men and women aged 18 years and above from the 2005 Survey of Social Development Trends-Health Security in Taiwan were analyzed.

RESULTS: Over 25% of the Taiwanese adults experienced insomnia. Difficulty initiating sleep (14.6%) was the most common type of insomnia, followed by early morning awakening (13.9%) and difficulty maintaining sleep (13.4%). The risk of EDS was three times as high for individuals with insomnia as for those without (95% confidence interval of odds ratio: 2.77-3.71). Insomnia status predicted poor psychological well-being even after controlling for sociodemographic factors and health status.

CONCLUSIONS: Taiwanese adults had a high prevalence of insomnia. Insomnia contributed at least partially to an individual's psychological well-being.