Later high school start times associated with longer actigraphic sleep duration in adolescents

Nov 6, 2018Sleep

Later high school start times linked to longer sleep in teenagers measured by activity trackers

AI simplified

Circadian Biology on OpenScience ↗PubMed ↗DOI ↗

Abstract

Adolescents starting school at 08:30 or later had 21-34 minutes longer sleep duration compared to those with earlier start times.

High school start times (SSTs) ranged from 06:00 to 11:05, with an average of 08:08.
Every 1-hour delay in SST was significantly associated with 21 minutes longer total sleep duration.
Later SSTs corresponded with later sleep onset by 16 minutes and later sleep offset by 39 minutes.
Adolescents starting school at 08:30 or later also experienced a later sleep offset by 32-64 minutes compared to peers with earlier start times.
All findings were based on objective sleep measurements and accounted for socioeconomic status.

AI simplified

STUDY OBJECTIVES: High school start times (SSTs) directly impact adolescents' sleep timing and duration. This study investigated the associations between SSTs and actigraphically-measured 24-hour sleep duration, sleep onset, sleep offset and sleep quality.

METHODS: This study included 383 adolescents (Mage = 15.5, SDage = 0.6 years) participating in the age 15 wave of the Fragile Families & Child Wellbeing Study, a national birth cohort study sampling from 20 large US cities. Multilevel models used daily observations (N = 1116 school days, Mdays = 2.9, SDdays = 1.4 per adolescent) of sleep and SSTs from concordant daily diary and actigraphy.

RESULTS: A diverse range of SSTs were included in our analyses (MSST = 08:08, SDSST = 39 minutes, RangeSST = 06:00-11:05), and are presented in the following categories for ease of interpretation: before 07:30, 07:30-07:59, 08:00-08:29, and 08:30 or later. Adolescents starting school at 08:30 or later exhibited significantly longer actigraphically-assessed 24-hour sleep duration (by 21-34 minutes, p < .05) and later sleep offset (by 32-64 minutes, p < .001) when compared with the adolescents grouped by earlier SSTs. SSTs were also analyzed continuously for comparison with existing literature, and results indicated that every 1-hour delay in SST was significantly associated with 21 minutes longer 24-hour sleep duration (p < .001), 16 minutes later sleep onset (p < .01), and 39 minutes later sleep offset (p < .001). All models controlled for covariates including socioeconomic status.

CONCLUSION: These findings support pediatric and public health expert recommendations for SSTs after 08:30. In our diverse national urban sample, adolescents with SSTs at 08:30 or later, compared with adolescents with earlier SSTs, had significantly longer actigraphy-measured sleep.

Full Text

Full text is available at the source.

View full text ↗

Later high school start times associated with longer actigraphic sleep duration in adolescents

Abstract

Full Text

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the circadian biology brief

Abstract

Full Text

Related papers

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the circadian biology brief