[Sleep disorders and child and adolescent psychiatric illnesses].

As a symptom of many psychiatric disorders of childhood and adolescence, sleep disturbances often complicate the course and treatment of the underlying disorder. A somatic aetiology, e.g., as in Kleine-Levin syndrome or narcolepsy, may lead to diagnostic misinterpretations. It is not clear whether specific alterations of sleep architecture already exist in this age group and are thus trait markers for psychiatric disorders. Although it is well-known that sleep problems in adults, especially insomnia, are important in the later development of depressive syndromes, it is not clear whether persistent sleep problems during childhood constitute markers of vulnerability for psychiatric disorders. This review demonstrates interactions between sleep disturbances and psychiatric disorders of childhood and adolescence and their importance for assessment and therapy.