1 National Reference Centre for Orphan Diseases, Narcolepsy, Idiopathic Hypersomnia, and Kleine-Levin Syndrome, Sleep-Wake Disorders Unit, Department of Neurology, Gui-de-Chauliac Hospital, CHU Montpellier, University of Montpellier, 34000 Montpellier, France; Institute of Neurosciences of Montpellier, INSERM, Montpellier, France. Electronic address: y-dauvilliers@chu-montpellier.fr.