Sleep-wake cycle in young and older persons with a lifetime history of mood disorders

Considering the marked changes in sleep and circadian rhythms across the lifespan, age may contribute to the heterogeneity in sleep-wake profiles linked to mood disorders. This study aimed to investigate the contributions of age and depression severity to sleep-wake disturbances. The Hamilton Depression Rating Scale (HDRS) was administered to assess current symptoms severity in 238 persons with a history of a mood disorder between 12 and 90 years of age (y.o.). Actigraphy was recorded over five to 22 days. Regression analyses and analyses of variance [age (12-19 y.o., 20-39 y.o., 40-59 y.o., and ≥ 60 y.o.) by depression severity (HDRS< and ≥ 8)] were conducted. The 12-19 y.o. and 20-39 y.o. groups had a delayed sleep schedule and acrophase compared to all other groups. The ≥ 60 y.o. group had a lower rhythmicity and amplitude (p ≤ .006) than the 12-19 y.o. group (p ≤ .046). Participants with a HDRS ≥ 8 spent longer time in bed, had later sleep offset times and had lower circadian rhythmicity than those with a HDRS