Sleep disturbances in individuals with first episode psychosis and clinical high-risk states: A systematic review

Background: Sleep disturbances are increasingly recognized as relevant components of the psychopathology of psychosis, emerging early in the illness trajectory and persisting over time. Indeed, individuals with first-episode psychosis (FEP) commonly experience disruptions in sleep architecture, including reduced sleep efficiency, increased sleep latency, and altered time spent in various sleep stages. These abnormalities are also reported in individuals with Clinical High-Risk (CHR) states, showing a significant correlation with cognitive and affective impairments. Methods: We conducted a systematic search across four main electronic databases, including PubMed, Web of Science, EMBASE, and PsycINFO, to specifically identify studies examining sleep parameters in FEP and CHR subjects compared to healthy controls. Eligibility criteria included quantitative and qualitative assessments of sleep. Results: The final selection consisted of 25 studies corresponding to 1255 patients and 342 healthy controls. Increased sleep latency and alterations in slow-wave sleep were frequently reported. These findings highlight the pervasiveness of sleep disturbances in individuals with early psychosis, though further research is needed to clarify their clinical significance. Evidence also suggests bidirectional relationships between sleep disturbances and psychotic symptoms, with sleep disruptions potentially exacerbating cognitive and emotional dysfunctions in FEP and CHR individuals. Conclusions: Sleep disturbances in FEP/ CHR populations are pervasive and may reflect underlying neurobiological mechanisms implicated in psychosis. These abnormalities represent modifiable targets for early intervention, with the potential to improve clinical and functional outcomes. Future research should explore longitudinal associations and the efficacy of sleep-focused interventions in the early stages of psychotic disorders.