Adolescents now are sleeping less per night than they did 20 years ago, according to research published online ahead of print February 16 in Pediatrics. The largest declines in nightly sleep time for all adolescents occurred between 1991 and 1995 and between 1996 and 2000. Furthermore, adolescents’ perceptions of whether their sleep is adequate often do not agree with objective sleep measures or consensus recommendations.
“Although the underlying reasons for the decreases in hours of sleep are unknown, there has been speculation that increased Internet and social media use and pressures due to the heightened competitiveness of the college admissions process are adding to the problem,” said Katherine M. Keyes, PhD, Assistant Professor of Epidemiology at Columbia University in New York City. “Declines in self-reported adolescent sleep across the last 20 years are concerning and suggest that there is potentially a significant public health concern that warrants health education and literacy approaches.”
The data result from the yearly Monitoring the Future survey, in which a nationally representative sample of students in the 8th, 10th, and 12th grades report how often they get seven or more hours of sleep and how often they get less sleep than they should. Dr. Keyes and colleagues examined data for 272,077 adolescents from 1991 to 2012.
Age-period-cohort analyses indicated that sleep has consistently decreased, especially during the late 1990s and early 2000s. Female students, members of racial or ethnic minorities, and students of lower socioeconomic status were less likely to report regularly getting seven or more hours of sleep per night, compared with males, non-Hispanic Caucasians, and students of higher socioeconomic status, respectively. The disparity according to race has increased in recent time periods. Members of racial or ethnic minorities and adolescents of low socioeconomic status, however, were more likely to self-report adequate sleep, compared with Caucasians and adolescents of higher socioeconomic status.
The largest decrease in the percentage of respondents getting seven hours of sleep per night was among people age 15. In 1991, 72% of respondents in this age group reported regularly getting seven or more hours of sleep per night. In 2012, 63% of adolescents in this age group reported regularly getting seven or more hours of sleep per night.
The National Sleep Foundation recommends nine hours of sleep per night for adolescents. Inadequate sleep is associated with mental health problems, academic problems, substance abuse, and weight gain.