Cardiovascular autonomic dysfunctions and sleep disorders.

Animal and human studies have shown that disorders of the autonomic nervous system may influence sleep physiology. Conversely, sleep disorders may be associated with autonomic dysfunctions. The current review describes the clinical presentation, supposed pathogenetic mechanisms and the diagnostic and prognostic implications of impaired cardiovascular autonomic control in sleep disorders. This dysfunction may result from a common pathogenetic mechanism affecting both autonomic cardiovascular control and sleep, as in fatal familial insomnia, or it may be mainly caused by the sleep disorder, as observed in obstructive sleep apnoea. For other sleep disorders, like primary insomnia, restless legs syndrome, narcolepsy type 1 and rapid eye movement sleep behaviour disorder, the causal link with the autonomic dysfunction and its possible impact on health remains unsettled. Given its clinical implications, most of the data available suggest that a systematic assessment of the association between sleep disorders and impaired autonomic control of the cardiovascular system is warranted. Understanding the mechanism of this association may also yield insights into the interaction between the autonomic nervous system and sleep.