Sex differences in bidirectional associations between dimensions of Fitbit-derived sleep and emotional health across 1 year in American Life in Realtime, a nationally representative sample of U.S. adults

Poor sleep predicts worse emotional health and vice versa in a large representative sample, particularly among females, highlighting the need for tailored intervention strategies that consider sex-specific patterns in sleep-emotional health dynamics. Statement of Significance The present study examined bidirectional associations between sleep and emotional health in a population-based sample of several hundred U.S. adults using objective sleep measures (Fitbit-derived) across 1 year. Within-person findings indicated that poor sleep health (shorter and longer total sleep time, lower sleep maintenance efficiency, and more variability in these measures) predicted worse emotional health. Poor sleep more frequently predicted poor emotional health than vice versa. On average, in between-person findings, people with poorer sleep had worse emotional health. Some findings were stronger in females. Using novel longitudinal, high-frequency wearable data from a nationally representative cohort over a year, these findings highlight the need for tailored intervention strategies that consider sex-specific patterns in sleep-emotional health dynamics.