[Relationships between prevalence of youth risk behaviors and sleep duration among Japanese high school students].

OBJECTIVES: This study aimed to clarify relationships between prevalence of risk behaviors and sleep duration among Japanese high school students. METHODS: Data from a national survey, the Japan Youth Risk Behavior Survey 2011 (the subjects were 9,778 students: 5,027 males, 4,751 females, in the first grade to the third grade of 102 schools randomly selected among high schools throughout Japan) was used for this analysis. We focused on nine items of risk behavior in JYRBS: "lack of vigorous physical activity," "skipping breakfast," "current cigarette use," "current alcohol use," "lifetime thinner use," "ever had sexual intercourse," "rarely or never wore seatbelts," "in a physical fight," and "seriously considered attempting suicide." RESULTS: Students with less than six hours of sleep duration accounted for approximately 40% of males and females. The odds ratios of prevalence of each of the nine risk behaviors were calculated on the basis of the group "six hours or more and less than eight hours" of sleep, whose prevalence of risk behaviors was the lowest. In the group with "four hours or more and less than six hours," the odds ratios of "lack of vigorous physical activity" and "skipping breakfast" for both males and females were significantly high. Furthermore, in the group with shorter sleep duration of "less than four hours," the odds ratios of all nine risk behaviors for males (odds ratios: 1.47-3.28) and eight risk behaviors (except for "rarely or never wore seatbelts") for females (1.54-4.68) were significantly high. On the other hand, in the group with long sleep duration of "10 hours or more," the odds ratios of "current cigarette use" and "lifetime thinner use" for both males and females were significantly high. CONCLUSION: It was shown that short sleep duration of less than six hours and long sleep duration of 10 hours or more related to the prevalence of youth risk behaviors among Japanese high school students. It was suggested that sleep duration should be considered as an important category of youth risk behaviors.

Effectiveness of drug abuse prevention program focusing on social influences among high school students: 15-month follow-up study.

OBJECTIVE: To examine the effectiveness of a drug abuse prevention program focusing on social influences for drug education classes in high school. METHODS: The social influence program in the experimental group used role-playing led by a pharmacist, a police officer and a teacher. The intervention evaluation used a quasi-experimental design. The subjects were first-year students from 10 high schools assigned to the experimental group (6 schools, 828 students) and the control group (4 schools, 408 students). In the control group, a pharmacist used a conventional information program in a lecture format. RESULTS: Regarding knowledge about drug abuse, in both the experimental and control groups, and for both males and females, a long-term effect was observed immediately after the program and lasted up to 15 months. For three other measures, attitudes toward drug abuse problem, self-efficacy regarding drug abuse prevention, and perception of social support for preventing drug abuse, a short-term effect was generally observed in the experimental group beginning immediately after the program and lasting for 3 months. A long-term effect was evident in high-risk students with positive opinions regarding drugs. In the control group and for both males and females, although an effect was generally evident immediately after the program, neither a short-nor a long-term effect was observed in males, suggesting the difficulty in achieving lasting effects. CONCLUSIONS: The social influence program in the experimental group showed remarkable effectiveness. Thus, the program may be useful for preventing drug abuse among high school students in Japan.