title: Non-24-Hour Sleep-Wake Rhythm Disorder in Sighted and Blind Patients.
abstract: Non-24-hour sleep-wake rhythm disorder (N24SWD) is a cyclic debilitating circadian rhythm sleep disorder characterized by an inability to sleep on a 24-hour schedule. Individuals isolated from a 24-hour light-dark cycle exhibit sleep-wake cycles different from 24 hours. Relatively rare in sighted patients, it may be associated with delayed sleep-wake rhythm disorder or psychiatric disorders. It is more common in totally blind individuals owing to the lack of light information reaching the circadian pacemaker in the hypothalamus. We review the clinical characteristics of patients with N24SWD, discuss the biological mechanisms that may underlie its development, and describe treatment strategies.
authors.affiliation: Department of Psychiatry, Nihon University School of Medicine, Oyaguchi-Kamicho, Itabashi, Tokyo 173-8610, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Uchiyama
authors.affiliation: Circadian Physiology Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, 221 Longwood Avenue, Boston, MA 02115, USA; Department of Medicine, Harvard Medical School, Boston, MA 02115, USA; School of Psychological Sciences, Monash University, Wellington Road, Melbourne, VIC 3800, Australia. Electronic address: slockley@hms.harvard.edu.
authors.forename: Steven W
authors.initials: SW
authors.lastname: Lockley
mesh_terms: D001766:Blindness / Q000150:complications / Q000503:physiopathology*; D006801:Humans; D020178:Sleep Disorders, Circadian Rhythm / Q000150:complications / Q000235:genetics / Q000503:physiopathology* / Q000628:therapy*
keywords: Blindness; Circadian rhythm sleep disorders; Free-running type; Hypernychthemeral syndrome; Melatonin; Nonentrained type; Non–24-hour sleep–wake rhythm disorder