Changes in sleep patterns in adolescents are more associated with pubertal indicators than age: A perfect storm with a dash of hormones.

As they become older, adolescents tend to prefer sleeping and rising later. Yet, it is still unclear if these sleep changes occur due to advancing age or because adolescents are more pubertally mature. This was investigated cross-sectionally in a sample of 121 Brazilian 9-to-17-year-olds. Participants reported their sleep habits (bed/rise times, time in bed [TIB] on weekdays and weekends, social jetlag) and circadian preferences (Morningness-Eveningness Scale for Children), which were analysed according to changes in age and pubertal status [self-rated Pubertal Development Scale (PDS); clinician-rated Tanner stages]. Older age related only to later weekday bedtimes. Later week/weekend bedtimes and reduced TIB were more associated with Tanner stages, especially pubic hair (adrenal) maturation, while evening preference was linked to higher PDS and genital/breast (gonadal) Tanner stages. Adolescents' sleep habits mapped differently onto age/pubertal status: higher adrenal development related to reduced sleep time, while higher gonadal development associated with eveningness preferences.