Prevalence of insomnia among Chinese adults in Hong Kong: a population-based study

Prevalence estimates of insomnia in western general populations are well documented, but population-based epidemiological data on insomnia in Chinese adults are scarce. The aims of the present study were to determine the prevalence of insomnia in the general population of Hong Kong, compare components of sleep disturbances and lifestyle factors stratified by sex, and identify risk factors for insomnia. Using a population-based cross-sectional design, a total of 5001 Chinese adults aged ≥18 years completed a telephone interview on the Pittsburgh Sleep Quality Index (PSQI), Hospital Anxiety and Depression Scale (HADS) and measures of quality of life (QoL) indexed by Medical Outcomes Study 12-item Short-Form Health Survey (SF12), lifestyle and sociodemographic details. Insomnia was defined by a PSQI global score >5. The resultant weighted prevalence of insomnia was 39.4%, equivalent to 2.2 million affected adults in Hong Kong. Women reported significantly poorer component and global sleep quality (all P < 0.05). Fully adjusted stepwise regression analyses identified non-full-time employment status, existing long-term health problems, alcohol consumption four to seven times per week, higher HADS scores, poor mental health component of QoL and low self-perceived health were associated significantly with insomnia (all P < 0.05). Our results suggest that insomnia is highly prevalent among Hong Kong Chinese adults and is associated with frequent use of alcohol, poor mental health and QoL.