An Epidemiological Study of the Relationship between Smoking Status and Insomnia among Japanese Adolescents

Abstract

In this study, we examined the relationship between smoking and insomnia by analyzing the results of an epidemiological study of approximately 100,000 adolescents in Japan. The survey design was a cross-sectional sampling survey. The targets of the survey were junior and senior high schools throughout Japan. Self-reported anonymous questionnaires were sent to sample schools for all students to complete. A total of 103,650 adolescents responded and 102,451 questionnaires were subjected to analysis. We found that the prevalences of difficulty in initiating sleep (DIS), difficulty in maintaining sleep (DMS), and early morning awaking (EMA) generally increased with the increases in the number of smoking days, the average number of cigarettes smoked per day and the degree of nicotine dependence. Multiple logistic regression analysis showed that the odds ratios (ORs) for all three sleep problems were significantly higher in daily smokers, smokers consuming 21 cigarettes or more per day, and smokers who always felt like smoking immediately after waking up. The present findings suggest that the close relationship between smoking status and insomnia may be explained by the association between the quantity of nicotine taken into the body and sleep. Therefore, health education to prevent both smoking as well as sleeping problems may be necessary in junior and senior high school.