title: Influence of melatonin on fatigue severity in patients with chronic fatigue syndrome and late melatonin secretion.
abstract: The effect of melatonin, a chronobiotic drug, was explored in 29 patients with chronic fatigue syndrome (CFS) and Dim Light Melatonin onset (DLMO) later than 21.30 hours, reflective of delayed circadian rhythmicity. The patients took 5 mg of melatonin orally, 5 h before DLMO during 3 months. Their responses to the checklist individual strength (CIS), a reliable questionnaire measuring the severity of personally experienced fatigue, were assessed twice with a 6-week interval immediately before the treatment and once after 3 months treatment. In the pre-treatment period the fatigue sub-score improved significantly. After treatment, the total CIS score and the sub-scores for fatigue, concentration, motivation and activity improved significantly. The sub-score fatigue normalized in two of the 29 patients in the pre-treatment period and in eight of 27 patients during treatment. This change was significant. In the patients with DLMO later than 22.00 hours (n=21) the total CIS score and the sub-scores for fatigue, concentration and activity improved significantly more than in the patients (n=8) with DLMO earlier than 22.00 hours. Melatonin may be an effective treatment for patients with CFS and late DLMO, especially in those with DLMO later than 22.00 hours.
authors.affiliation: Department of Neurology, Sleep-Wake Disorders and Chronobiology, Hospital De Gelderse Vallei, Ede, and Department of Medical Psychology, Radbound University Medical Centre, Nijmegen, The Netherlands.
authors.forename: R O
authors.initials: RO
authors.lastname: van Heukelom
authors.forename: J B
authors.initials: JB
authors.lastname: Prins
authors.forename: M G
authors.initials: MG
authors.lastname: Smits
authors.forename: G
authors.initials: G
authors.lastname: Bleijenberg
mesh_terms: D002940:Circadian Rhythm / Q000187:drug effects*; D004334:Drug Administration Schedule; D015673:Fatigue Syndrome, Chronic / Q000188:drug therapy*; D006801:Humans; D008550:Melatonin / Q000008:administration & dosage* / Q000378:metabolism*; D007319:Sleep Initiation and Maintenance Disorders / Q000188:drug therapy; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D008550:Melatonin