Sleep–wake patterns in schizophrenia patients compared to healthy controls

Abstract

Objectives. The aim of this study was to examine the differences between a sample of patients with schizophrenia and a sample of healthy controls in terms of sleep patterns and self-reported sleep quality and quality of life (QoL). Methods. Thirty-four schizophrenia outpatients (SP), 12 women and 22 men and 34 healthy subjects (HS), 15 women and 19 men, participated in this study. Wrist-actigraphy recordings and a sleep diary were used for sleep–wake cycle assessment. The quality of sleep was measured using the Pittsburgh Sleep Quality Index (PSQI), the QoL was evaluated using the World Health Organization Quality of Life – Abbreviated version (WHOQOL-Bref). The Positive and Negative Syndrome Scale (PANSS) was used for psychopathology assessment. Results. Patients sleep more at night, but have poorer sleep efficiency, than HS. Sleep latency and nighttime awakenings were significantly higher in SP. Self-reported QoL scores were significantly higher, in all four domains, in HS. Scores on PSQI were significantly higher in SP, indicating a worse quality of sleep. Two disturbed patterns of sleep–wake phase were found in SP: advance sleep-phase syndrome (ASPS) (N = 3) and irregular sleep–wake rhythm (N = 3). Conclusion. Schizophrenia patients have more disturbed sleep–wake patterns and poor sleep quality and quality of life compared with healthy controls.