TY - JOUR
T1 - Later high school start times associated with longer actigraphic sleep duration in adolescents
AU - Nahmod, Nicole G.
AU - Lee, Soomi
AU - Master, Lindsay
AU - Chang, Anne Marie
AU - Hale, Lauren
AU - Buxton, Orfeu M.
N1 - Publisher Copyright:
© Sleep Research Society 2018. Published by Oxford University Press on behalf of the Sleep Research Society.
PY - 2019/2/1
Y1 - 2019/2/1
N2 - 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 (M age = 15.5, SD age = 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, M days = 2.9, SD days = 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 (M SST = 08:08, SD SST = 39 minutes, Range SST = 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.
AB - 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 (M age = 15.5, SD age = 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, M days = 2.9, SD days = 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 (M SST = 08:08, SD SST = 39 minutes, Range SST = 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.
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U2 - 10.1093/sleep/zsy212
DO - 10.1093/sleep/zsy212
M3 - Article
C2 - 30395345
AN - SCOPUS:85061514252
SN - 0161-8105
VL - 42
JO - Sleep
JF - Sleep
IS - 2
M1 - zsy212
ER -