Hours of sleep and aggressive behavior among adolescents

OBJECTIVE: To examine the association between number of hours of sleep and aggressive behavior among adolescents. METHODS: Data come from a stratified random sample of high school students in Boston, MA who completed the paper-and-pencil survey during class in 2006. Outcome variables include past month prevalence of: (1) verbal aggression (i.e., having had a yelling argument with a non-family member), (2) moderate aggression (i.e., having pushed, shoved, or slapped someone), and (3) serious aggression (i.e., having hit, punched, kicked or choked someone). Hours of sleep was computed using students' reports of what time they usually go to bed on weeknights, and what time they need to get up to be on time for school. We examined the association between aggression and hours of sleep, and present unadjusted risk ratios (RR). Generalized linear multi-level models that account for school factors will be presented later. RESULTS: Of the 1,215 respondents, 57% were female, 30% were Hispanic, 47% were Non-Hispanic Black, and 13% were Non-Hispanic White. Only 7.3% could get more than 8 hours of sleep; 86% had to be up by 6 am to be on time for school. Students who got =<6 hours were more likely to display serious aggression (42.8%) compared to those with got =>8 hours (30.1%; RR = 1.42, 95% CI = 1.16-1.74). Results were similar for verbal aggression. DISCUSSION: Results suggest that aggressive behavior is inversely related to hours of sleep. Changes in policies regarding early school start times should be considered.