Sleep disturbance as a marker of postpartum psychosis risk: a prospective actigraphy study.

Background: Postpartum Psychosis (PP) is a severe perinatal psychiatric disorder affecting 1-2 in 1000 individuals following childbirth. Most episodes emerge within the first two weeks postpartum and commonly present with mania and decreased need for sleep. The postnatal period is a time of profound sleep disruption and sleep deprivation is a known trigger for mania and psychosis. Despite growing recognition of the role of sleep in the onset and progression of PP, this relationship remains poorly understood. Existing research is largely retrospective, relies on self-reported data and primarily focuses on women with pre-existing bipolar disorder. This prospective study will integrate subjective and objective sleep measures to investigate the relationship between sleep disturbance and postnatal mania. We aim to establish whether sleep patterns in late pregnancy or the early postpartum period can predict mania as a marker of PP.

Methods: This prospective observational cohort study is recruiting pregnant women and will follow participants from the late third trimester until two weeks postpartum. We aim to recruit 100 participants, including individuals with and without psychiatric illness, to ensure broader applicability of the findings and capture the full spectrum of postnatal mania risk. Participants will wear a wrist accelerometer continuously during this period to monitor rest-activity patterns and infer objective sleep parameters including sleep duration, efficiency and fragmentation. Self-reported sleep quality and mood symptoms will be measured using the Pittsburgh Sleep Quality Index (PSQI), Altman Self-Rating Mania Scale (ASRM) and Edinburgh Postnatal Depression Scale (PSQI) at baseline and at days 3-5 and 12-14 postpartum. Actigraphy data will be analysed using the GGIR package in R. Associations between sleep measures and ASRM scores will be assessed using Pearson and Spearman correlation coefficients.

Discussion: This study is the first to prospectively investigate sleep and postnatal mania risk in a cohort including both high- and low-risk individuals. By integrating actigraphy with validated self-report measures, it aims to identify rest-activity patterns that may serve as early indicators of PP. Early recognition of sleep disturbances associated with postnatal mania could inform targeted interventions, improving clinical outcomes for women and families affected by PP.