Continuity and change in poor sleep from childhood to early adolescence.
OBJECTIVE
We examined associations between pubertal maturation and sleep in early adolescence, at age 12 y, and continuity and change in actigraphy-based sleep and parent-reported sleep disorders from age 8 to 12 y. We also explored longitudinal associations between actigraph estimates of sleep and sleep disorders.


METHODS
A cohort study of children born in 1998 and tested at ages 8 y (standard deviation [SD] = 0.3) and 12 y (SD = 0.5).


METHODS
A total of 348 children participated in cross-sectional analyses. We had longitudinal actigraphy data for 188 children and repeated parent reports of sleep disorders for 229 children.


RESULTS
At age 8 y, participants wore actigraphs for 7.1 nights (SD = 1.2, range 3-14) on average and at age 12 y for 8.4 nights (SD = 1.7, range 3-11). Sleep disorders were parent-rated based on the Sleep Disturbance Scale for Children. Pubertal maturity was self-reported at age 12 y using the continuous Pubertal Development Scale and the picture-assisted categorical Tanner scales.


RESULTS
Significant mean-level changes toward shorter but higher quality sleep occurred over time. Sleep variables had low to high rank-order stability over time. Sleep disorders were highly stable from age 8 to 12 y. Actigraphy-based sleep and parent-rated sleep disorders showed no association either in cross-section or longitudinally. Pubertal maturation was not associated with worse sleep.


CONCLUSIONS
Sleep in early adolescence can be anticipated from childhood sleep patterns and disorders, but is not associated with pubertal maturity. Although sleep duration becomes shorter, sleep quality may improve during early adolescence. Parent-rated sleep disorders are distinct from actigraph estimates of sleep.
University of Helsinki, Institute of Behavioural Sciences, Helsinki, Finland.
Anu-Katriina
AK
Pesonen
University of Helsinki, Institute of Behavioural Sciences, Helsinki, Finland.
Silja
S
Martikainen
University of Helsinki, Institute of Behavioural Sciences, Helsinki, Finland.
Kati
K
Heinonen
National Institute for Health and Welfare, Children's Hospital, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland.
Karoliina
K
Wehkalampi
University of Helsinki, Institute of Behavioural Sciences, Helsinki, Finland.
Jari
J
Lahti
National Institute for Health and Welfare, Children's Hospital, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland.
Eero
E
Kajantie
University of Helsinki, Institute of Behavioural Sciences, Helsinki, Finland.
Katri
K
Räikkönen
D056044:Actigraphy; D002648:Child; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010290:Parents; D011627:Puberty / Q000502:physiology*; D057566:Self Report; D012890:Sleep / Q000502:physiology*; D012893:Sleep Wake Disorders / Q000175:diagnosis / Q000503:physiopathology*
Actigraph; adolescents; children; cohort; longitudinal; puberty; sleep disorder