Epidemiological study on sleep habits and insomnia of new outpatients visiting general hospitals in Japan.
A large scale epidemiological survey of sleep habits, specifically for insomnia, was conducted using 6277 new outpatients from 11 general hospitals in Japan. They were requested to answer a questionnaire newly designed for this study, which consisted of 34 questions concerning sociodemographic characteristics, current medical conditions, sleep habits, current or past sleep complaints, symptoms of parasomnia, use of hypnotics/anxiolytics and other aspects of daily life. Insomnia was the focus of analysis using chi2 statistics and, additionally, logistic regression to explore the predictors of insomnia. Bedtime was 23:30 and wake-up time was 6:35 on average, with a mean sleep time of 6.77 h on weekdays. The number of subjects with current sleep complaints was 1276, of which 735 (11.7% of the total sample) had insomnia lasting for 1 month or more. Only 37.6% of those were taking hypnotics and/or anxiolytics. Old age, female sex, neurology, psychiatry, early bedtime, late wake-up time, living alone and dissatisfaction with the bedroom environment for sleep were found to be associated with long-term insomnia. This study helps to provide a framework for further studies using the general population.
Ishigooka
J
J
Department of Psychiatry, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
Suzuki
M
M
Isawa
S
S
Muraoka
H
H
Murasaki
M
M
Okawa
M
M
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D016021:Epidemiologic Studies; D005195:Family Relations; D005260:Female; D006760:Hospitalization; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D001523:Mental Disorders / Q000150:complications; D008875:Middle Aged; D012307:Risk Factors; D012737:Sex Factors; D012890:Sleep; D007319:Sleep Initiation and Maintenance Disorders / Q000453:epidemiology* / Q000209:etiology / Q000523:psychology