SLEEP AND PSYCHOPATHOLOGY

This article examines the relationship between sleep disturbance and p sychopathology. Epidemiological, cross-sectional, and longitudinal dat a suggest a high rate of comorbidity between sleep disturbance and psy chopathology, particularly between insomnia, anxiety, and depression. Between 50% and 80% of psychiatric patients complain of sleep disturba nces during the acute phase of their illness. Conversely, among treatm ent-seeking individuals with a primary complaint of insomnia and rando mly selected community samples, approximately one third display a conc urrent psychopathology, one third exhibit psychological symptoms that do not necessarily exceed the threshold for a psychiatric disorder, an d another third present insomnia as a functionally autonomous disorder . There is a positive relationship between severity of sleep disturban ces and concurrent psychopathology, but unequivocal evidence of a caus e-and-effect relationship is still lacking. However, longitudinal data suggest that anxiety and stressful life events often precede acute sl eep difficulties, whereas persistent insomnia may be a risk factor for subsequent development of depression. Implications for the prevention and treatment of coexisting sleep disturbance and psychopathology are discussed.