The great sleep recession: Changes in sleep duration among US adolescents, 1991-2012

Abstract

BACKGROUND: Average nightly sleep times precipitously decline from childhood through adolescence. There is increasing concern that historical shifts also occur in overall adolescent sleep time. METHODS: Data were drawn from Monitoring the Future, a yearly, nationally representative crosssectional survey of adolescents in the United States from 1991 to 2012 (N = 272 077) representing birth cohorts from 1973 to 2000. Adolescents were asked how often they get ≥7 hours of sleep and how often they get less sleep than they should. Age-period-cohort models were estimated. RESULTS: Adolescent sleep generally declined over 20 years; the largest change occurred between 1991-1995 and 1996-2000. Age-period-cohort analyses indicate adolescent sleep is best described across demographic subgroups by an age effect, with sleep decreasing across adolescence, and a period effect, indicating that sleep is consistently decreasing, especially in the late 1990s and early 2000s. There was also a cohort effect among some subgroups, including male subjects, white subjects, and those in urban areas, with the earliest cohorts obtaining more sleep. Girls were less likely to report getting ≥7 hours of sleep compared with boys, as were racial/ethnic minorities, students living in urban areas, and those of low socioeconomic status (SES). However, racial/ethnic minorities and adolescents of low SES were more likely to self-report adequate sleep, compared with white subjects and those of higher SES. CONCLUSIONS: Declines in self-reported adolescent sleep across the last 20 years are concerning. Mismatch between perceptions of adequate sleep and actual reported sleep times for racial/ ethnic minorities and adolescents of low SES are additionally concerning and suggest that health education and literacy approaches may be warranted.