Obstructive Sleep Apnea Syndrome: An Emerging Risk Factor for Dementia.

Epidemiological studies have suggested that obstructive sleep apnea syndrome (OSAS) may increase the risk of developing cognitive impairment. In patients with Alzheimer's disease (AD), the prevalence of OSAS is much higher than that expected in cognitively healthy subjects. A deeper knowledge of the pathophysiological link between OSAS and AD and the demonstration that OSAS may directly influence the development of cognitive alterations, would increase prevention and treatment strategies for AD patients. In this article, we discuss the evidence of the association between OSAS and dementia. Moreover, we present data about the functional and anatomic cerebral changes induced by OSAS and the possible effects on cognitive activities and on AD pathogenesis. The possibility to positively influence cognitive impairment by OSAS treatment will be also discussed.