Older schizophrenia patients have more disrupted sleep and circadian rhythms than age-matched comparison subjects

Patient reports and laboratory studies suggest schizophrenia patients have disrupted sleep across age groups. Studies have not compared overall sleep/wake patterns or circadian (24-h) activity rhythms of older community dwelling schizophrenia patients to matched comparison subjects. This study examined whether older schizophrenia patients had more disrupted sleep/wake patterns and circadian activity rhythms than age- and gender-matched normal comparison subjects (NCS). Twenty-eight older schizophrenia patients and 28 age- and gender-matched NCS were studied with three days of continuous wrist actigraphy. Nighttime and daytime actigraphically estimated sleep and wake, circadian activity rhythms and light exposure patterns were compared with and without years of education as a covariate. Patients spent longer in bed, had more disrupted nighttime sleep, slept more during the day, and had less robust circadian rhythms of activity and light exposure compared to NCS. Differences persisted in education-adjusted analyses. Within patients, working was associated with improved sleep and circadian rhythms. Findings suggest the sleep and circadian rhythm disruption of older schizophrenia patients was more extensive than that of matched NCS suggesting patients' sleep disruption was above and beyond what is attributable to advanced age alone. A need exists to develop multicomponent interventions to address sleep difficulties specific to older schizophrenia patients.