title: A 4-year follow-up of patients with medication-overuse headache previously included in a randomized multicentre study.
abstract: The aim of this study was to evaluate the long-term outcome in 61 patients with medication-overuse headache (MOH) who 4 years previously had been included in a randomized open-label prospective multicentre study. Sixty patients still alive after 4 years were invited to a follow-up investigation. Fifty patients (83%) participated. Sixteen visited a neurologist, 22 were interviewed through telephone, 2 gave response by a letter, and 10 were evaluated through hospital records. The influence of baseline characteristics on outcome 4 years later was evaluated by non-parametric tests. p values below 0.01 were considered significant. At follow-up, the 50 persons had a mean reduction of 6.5 headache days/month (p < 0.001) and 9.5 acute headache medication days/month (p < 0.001) compared to baseline. Headache index/month was reduced from 449 to 321 (p < 0.001). Sixteen persons (32%) were considered as responders due to a ≥50% reduction in headache frequency from baseline, whereas 17 (34%) persons met the criteria for MOH. None of the baseline characteristics consistently influenced all five outcome measures. Total Hospital Anxiety and Depression Scale (HADS) score at baseline was predictors (p < 0.005) for being a responder after 4 years. At 4 years' follow-up, one-third of the 50 MOH patients had ≥50% reduction in headache frequency from baseline. A low total HADS score at baseline was associated with the most favorable outcome.
authors.affiliation: Department of Neuroscience, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway. knut.hagen@ntnu.no
authors.forename: Knut
authors.initials: K
authors.lastname: Hagen
authors.forename: Claus
authors.initials: C
authors.lastname: Albretsen
authors.forename: Steinar T
authors.initials: ST
authors.lastname: Vilming
authors.forename: Rolf
authors.initials: R
authors.lastname: Salvesen
authors.forename: Marit
authors.initials: M
authors.lastname: Grønning
authors.forename: Grethe
authors.initials: G
authors.lastname: Helde
authors.forename: Gøril
authors.initials: G
authors.lastname: Gravdahl
authors.forename: John-Anker
authors.initials: JA
authors.lastname: Zwart
authors.forename: Lars Jacob
authors.initials: LJ
authors.lastname: Stovner
mesh_terms: D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D051271:Headache Disorders, Secondary / Q000188:drug therapy* / Q000453:epidemiology*; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests; D015995:Prevalence; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D012008:Recurrence; D016896:Treatment Outcome; D055815:Young Adult