Syndrome d'apnées du sommeil, diabète et insulinorésistance

Sleep apnea syndrome is a prevalent disease affecting approximately 5% of adults in industrialized country. The pandemic of obesity observed in the same countries explains the increase in the prevalence of type 2 diabetes mellitus, glucose intolerance and hyperinsulinemia. Although obesity is also a risk factor for sleep apnoea syndrome, there is a growing body of literature that implicates sleep apnoea syndrome in the pathogenesis of type 2 diabetes and insulino-resistance, independently of obesity. Epidemiologic studies have shown a relationship between abnormal glucose metabolism and sleep fragmentation or nocturnal hypoxemia resulting from sleep disordered breathing. Experimental data confirm the influence of intermittent hypoxemia and abnormalities in sleep itself on the mechanisms regulating glucose level. Hypoxia and sleep fragmentation can lead to increase of sympathetic activity, alteration of neuroendocrine function and release of proinflammatory cytokines and adipokines. These events might contribute to the development of abnormal glucose metabolism. Although the causal relationship between sleep apnoea syndrome and impaired glucose metabolism is not yet demonstrated, this relationship independent of obesity should have clinical implication.