Quality of sleep in patients with schizophrenia is associated with quality of life and coping
Department of Psychiatry, R.L. Roudebush VA Medical Center, 1481 W. 10th St, Indianapolis, IN, 46202, USA and Department of Psychiatry, Indiana University School of Medicine, 1111 W. 10th St, Indianapolis, IN, 46202, USA
BMC Psychiatry 2005, 5:13 doi:10.1186/1471-244X-5-13Published: 3 March 2005
While sleep disturbance is widespread in schizophrenia it is less clear whether sleep disturbance is uniquely related to impaired coping and perceived quality of life.
We simultaneously assessed sleep quality, symptoms, and coping in 29 persons with schizophrenia or schizoaffective disorder in a post acute phase of illness. Assessment instruments included the Pittsburgh Sleep Quality Index; the Positive and Negative Symptom Scale; the Heinrichs Quality of Life Scale; and the Ways of Coping Scale. Multiple regressions were performed predicting quality of life and coping from sleep quality controlling for age and symptom severity. On a subset of seven subjects non-dominant wrist actigraphy was used as an objective check of their self-reported poor sleep.
Analyses revealed that poor sleep quality predicted low quality of life (r = -0.493; p = .022) and reduced preference for employing positive reappraisal when facing a stressor (r = -0.0594; p = 0.0012). Actigraphy confirmed poor sleep quality in a subset of subjects. They had shorter sleep duration (p < .0005), shorter average sleep episodes (p < .005) and more episodes of long awakening (p < 0.05) than community norms.
The results are consistent with the hypotheses that poor sleep may play a unique role in sustaining poor quality of life and impaired coping in patients with schizophrenia. These associations may hold for community controls as well.