[Obstructive sleep apnoea and metabolic syndrome]

Metabolic syndrome, i. e., the combined occurrence of obesity, arterial hypertension, insulin resistance and dyslipidaemia (increased triglycerides, reduced HDL cholesterol), is associated with a marked increase in cardiovascular risk. The prevalence of metabolic syndrome in patients with obstructive sleep apnoea (OSA) is very high. Obesity is the main risk factor for OSA and OSA itself is now considered to be the most frequent cause of secondary arterial hypertension. Due to the confounding influence of obesity, the causal connection between OSA and metabolic disturbances is less well established, however, epidemiological data are at least in favour of an independent link between OSA and insulin resistance. It is known that CPAP therapy can ameliorate OSA-associated hypertension. In contrast, the effects of CPAP treatment on insulin resistance and dyslipidaemia have to be further elucidated by large, randomised interventional trials.