Sleep problems, tiredness, and psychological symptoms among healthy adolescents.

OBJECTIVE To examine the contribution of adolescents' sleep problems and tiredness to psychological symptoms after accounting for shared risk and psychological co-morbidity. METHODS Secondary analyses of cross-sectional data on 12-16-year-old (N = 980) adolescents without chronic illness, functional limitation, or developmental delay. Adolescents rated sleep problems, tiredness, and psychological symptoms. Parents provided information about risk factors, adolescent tiredness, and psychological symptoms. RESULTS Prior to accounting for psychological co-morbidity, most sleep variables were significant correlates of adolescent-, but not parent-rated, psychological symptoms. After accounting for psychological co-morbidity: nightmares were associated with adolescent-rated anxiety/depression; sleeping more than others was associated with adolescent-rated aggression; trouble sleeping was associated with adolescent-rated attention problems, anxiety/depression, and withdrawal; and adolescent-rated tiredness was associated with adolescent-rated aggression and withdrawal. CONCLUSIONS Studies examining sleep and psychopathology should control for psychological co-morbidity.