CLINICAL NEUROSCIENCE AND NEUROPATHOLOGYReduced hypocretin (orexin) levels in dementia with Lewy bodiesLessig, Stephaniea; Ubhi, Kirena; Galasko, Douglasa; Adame, Anthonya; Pham, Emileya; Remidios, Kellya; Chang, Michaela; Hansen, Lawrence A.a b; Masliah, Eliezera bAuthor Information Departments of aNeurosciences bPathology, University of California, San Diego, La Jolla, California, USA Correspondence to Stephanie Lessig, MD, Neurology Service (9127), 3350 La Jolla Village Drive La Jolla, CA 92161, USA Tel: +1 858 552 8585 x5409; fax: +1 858 552 7513; e-mail: [email protected] Received 17 March 2010 accepted 11 May 2010 NeuroReport: August 4, 2010 - Volume 21 - Issue 11 - p 756-760 doi: 10.1097/WNR.0b013e32833bfb7c Buy Metrics Abstract Sleep disorders are observed in Parkinson's disease, dementia with Lewy bodies, and Alzheimer's disease; however, the underlying mechanisms are unclear. Reduced hypocretin (orexin) levels are reported in Parkinson's disease and sleep disorders, including narcolepsy; however, its levels in dementia with Lewy bodies and Alzheimer's disease and its relationship with sleep disturbances in these disorders remain undetermined. We examined hypocretin levels in qdementia with Lewy bodies and Alzheimer's disease cases and correlated these with sleep habits and clinical characteristics. Although limited hypocretin alterations were observed in Alzheimer's disease, we show reduced neocortical hypocretin immunoreactivity in dementia with Lewy bodies patients correlating with hypersomnolence and α-synuclein levels. These results suggest the involvement of hypocretin in sleep disorders in dementia with Lewy bodies. © 2010 Lippincott Williams & Wilkins, Inc.