Sleep disorders and the autonomic nervous system

SLEEP DISORDERS AND AUTONOMIC NERVOUS SYSTEM Federica Provini IRCCS, Istituto delle Scienze Neurologiche di Bologna Department of Biomedical and Neuromotor Sciences, University of Bologna Italy Sleep and autonomic nervous system (ANS) are interdependent by virtue of their common controls, neurobiological substrates and functions. Major confirmation of this is the presence of dynamic and synchronous fluctuations in sleep phases and autonomic variables during the physiological sleep. Much evidence from experimental and clinical studies supports the bidirectional nature of the relationship between sleep disorders and ANS dysfunctions. Patients with autonomic dysfunctions may present sleep disorders and conversely patients with untreated sleep disorders may develop features suggestive of autonomic dysfunctions. In many neurodegenerative disorders sleep-wake cycle disorders appear in almost all or in all patients, often associated with autonomic dysfunctions, with a negative prognostic impact, particularly when involving cardiovascular or respiratory control. In neurodegenerative diseases, the pathological disruption of sleep microstructure leads to an insufficient response to potential internal or environmental disruptors. In these conditions the sleeping brain offers a fragile interface against ongoing menaces as the paucity of EEG arousals responses mirrors the shortage of autonomic reactions. In all these conditions, an accurate analysis of sleep disorders and autonomic dysfunctions is of crucial importance to choose the proper therapeutic approach.