ABSTRACT
Chronic fatigue syndrome (CFS) is a chronic, complex, systemic disease that often can profoundly affect the lives of patients. Sleep disturbances are frequently reported in CFS, and these complaints have been shown to persist throughout the course of the illness. Patients with CFS describe sleep to be a vital process for health and well-being, which has a direct bearing on the course and progression of their illness. Considered together, the theoretical model of the role of sleep in CFS may explain the process by which fatigue develops, is maintained and continues via a cycle of irregular sleeping patterns, biological dysregulation, and cognitive and behavioral responses. Self-report techniques have been employed to determine the perceptual role of sleep in CFS and include the use of sleep diaries and sleep questionnaires, such as the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale.
