title: Nocturnal cortisol and melatonin secretion in primary insomnia.
abstract: The present study investigated evening and nocturnal serum cortisol and melatonin concentrations in patients with primary insomnia to test if this clinical condition is accompanied by an increase of cortisol secretion and a simultaneous decrease of nocturnal melatonin production. Ten drug-free patients (4 males, 6 females) with primary insomnia (mean age+/-S.D.: 39.2+/-9.1 years) and 10 age- and gender-matched healthy controls participated in the study. All subjects spent three consecutive nights in the sleep laboratory with polysomnography. Measurement of cortisol and melatonin (from 19:00 h to 09:00 h) was performed prior to and during the last laboratory night. Contrary to expectation, cortisol secretion did not differ between healthy controls and insomniac patients. On the other hand, nocturnal melatonin production was significantly diminished in insomniac patients. Polysomnographically determined sleep patterns, in contrast to subjective ratings of sleep, demonstrated only minor alterations of sleep in the insomniac group. The lack of increased cortisol secretion in the patients with primary insomnia indicates that results from studies on the biological consequences of experimental sleep loss in healthy subjects cannot be applied to primary insomnia in general, especially if there are only minor objective sleep alterations. In spite of the negligible objective sleep disturbances in the present sample, nocturnal melatonin production was reduced, which tentatively suggests a role for this hormone in primary insomniacs. The pathophysiological significance of this finding is, however, still a matter of debate.
authors.affiliation: Department of Psychiatry and Psychotherapy, University Hospital of Freiburg, Hauptstrasse 5, 79104, Freiburg, Germany. dieter_riemann@psyallg.ukl.uni-freiburg.de
authors.forename: Dieter
authors.initials: D
authors.lastname: Riemann
authors.forename: Torsten
authors.initials: T
authors.lastname: Klein
authors.forename: Andrea
authors.initials: A
authors.lastname: Rodenbeck
authors.forename: Bernd
authors.initials: B
authors.lastname: Feige
authors.forename: Andrea
authors.initials: A
authors.lastname: Horny
authors.forename: Ruth
authors.initials: R
authors.lastname: Hummel
authors.forename: Gesa
authors.initials: G
authors.lastname: Weske
authors.forename: Anam
authors.initials: A
authors.lastname: Al-Shajlawi
authors.forename: Ulrich
authors.initials: U
authors.lastname: Voderholzer
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000328:Adult; D002940:Circadian Rhythm / Q000502:physiology; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000096:biosynthesis* / Q000097:blood; D007118:Immunoassay; D008297:Male; D008550:Melatonin / Q000096:biosynthesis* / Q000097:blood; D008875:Middle Aged; D017286:Polysomnography; D007319:Sleep Initiation and Maintenance Disorders / Q000175:diagnosis / Q000378:metabolism*; D012895:Sleep, REM / Q000502:physiology
chemical_list: D008550:Melatonin; D006854:Hydrocortisone