Sex and age differences in sleep macroarchitecture in childhood and adolescent depression

Subject Objective: To evaluate age and sex differences in sleep macro-architecture in children and adolescents with major depressive disorder. Design: Ninety-seven (50 F, 47 M) symptomatic unmedicated depressed outpatients were compared with 76 healthy controls (42 F, 34 M) matched for age and sex. Setting: Participants spent 2 consecutive nights in the sleep laboratory. Participants: One hundred seventy-three children and adolescents, aged 8 to 18 years. Measurements and Results: Significant group-by-age-by-sex interactions were evident for total sleep period, percentage of Stage 1 sleep, percentage of Stage 2, percentage of slow-wave sleep, and rapid eye movement (REM) sleep latency. The depressed adolescent boys had the greatest sleep disturbance with the highest amount of percentage of Stage 1 sleep, the shortest REM latency, and the least percentage of slow-wave sleep and number of minutes of slow-wave sleep in the first non-REM period. There were minimal age differences in sleep parameters between depressed children and adolescent girls. Within age groups, the sex differences were minimal in the healthy controls. The sex differences within the depressed group were substantially larger than controls. Conclusions: These findings suggest a differential developmental influence on sleep in early-onset depression that is heavily dependent on sex. Sex differences are substantially smaller in healthy individuals compared with those with depression, in agreement with previous studies in depressed adults.