Sleep apnea syndrome and its complications.

In this article we summarize the available information regarding the epidemiology, the pathophysiology as well as the risk factors and complications of the sleep apnea syndrome (SAS). Central, obstructive and mixed forms of SAS are known, however, the obstructive form is (resulting from the actual high prevalence of obesity) definitely the most frequent. Latest years of experimental and clinical research have pointed towards the clinical importance of this sleep related breathing disorder. High prevalence in the population and especially the cardiovascular complications (e. g. systemic and pulmonary hypertension, atherosclerosis, arrhythmias) have contributed to the recent increase in knowledge about SAS. Nevertheless, there are numerous unsolved problems and unanswered questions in the pathophysiology of SAS. Future studies should, thus, provide us with more information and shed light on regarding the hidden mysteries of SAS.