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 longterm 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 C50% 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, onethird of the 50 MOH patients had C50% reduction in headache frequency from baseline. A low total HADS score at baseline was associated with the most favorable outcome.