Long-term outcomes of nummular headache: A series of 168 patients and 1198 patient-years of follow-up

Abstract

Background Since the first description of nummular headache (NH), more than 500 cases have been described, delineating its clinical phenotype and response to treatment. However, data on the natural history of NH and outcomes during long-term follow-up are not currently available. The present study aimed to describe the long-term outcomes and follow-up of a large series of patients with NH. Methods A descriptive observational ambisective study with a series of cases was conducted. The study population included adult patients with primary NH and a minimum of 12 months of follow-up. Demographic variables, previous medical history, clinical phenotype, diagnosis and treatment of NH, temporal pattern, and long-term evolution were analysed. Results In total, 168 patients were enrolled and followed for a median [interquartile range (IQR)] of 80.5 (55–118.5) months. The temporal pattern after NH onset was chronic in 67.9% and, at diagnosis, the median (IQR) number of pain days per month was 20 [10–30] days with 138 (82.1%) patients with ≥8 days of pain per month. Preventive treatment was needed by 112 (66.7%) patients. The most frequently used drugs were gabapentin (69/112; 61.6%), onabotulinumtoxinA (38/112; 33.9%), amitriptyline (31/112; 27.7%) and lamotrigine (21/112; 18.7%). Response to preventive treatment was at least partial in 91/112 (81.3%) patients. At the end of follow-up, 81 (48.2%) patients had inactive NH. Of patients with active NH, the median (IQR) number of headache days per month was 3 (1–12) days and patients had ≥8 days of pain in 35 (20.8%) cases. Conclusions Long-term outcomes of NH were positive in most patients. After a median of 6.7 years of follow-up, 48% of cases were inactive. Two-thirds of patients required preventive treatment, and 80% of them were treatment-responsive. In NH cases that remained symptomatic, the headache frequency was lower, and the proportion of patients with chronic NH decreased from 68% to 11%.