[Sleep disturbances from the internist's viewpoint].

Sleep disorders are common and can be caused by somatic diseases. Chronic pain as well as heart and lung conditions are able to interfere with the normal sleep pattern. Obstructive sleep apnea is caused by a deranged central control of breathing occurring during sleep and leads to a sleep-fragmentation and consequently to daytime hypersomnolence. A problem oriented meticulous history can give valuable insights and distinct diagnostic considerations form the basis for an eventually successful therapeutic approach. Polysomnography is done in particularly puzzling cases and for evaluation of invasive therapeutic measures.