Randomised study of botulinum toxin type A (BoNT/A) in the treatment of chronic tension type headache

Abstract

Introduction : Tension-type headache (TTH) is the most common form of headache, with a lifetime prevalence of up to 30% in general population. Symptoms may vary in typology and intensity and include constriction, sense of pressure and tightness. Despite a significantly high prevalence in the general population, little studies have been performed considering etiology of the syndrome, and also considering treatment. Pathophysiological mechanisms may include the central nervous system, producing increased tension in the pericranial muscles and pain. By blocking the presynaptic cholinergic nerve terminal, interfering with acetylcholine exocitosis, BoNT/A could address this feature because of a myorelaxant effect. Material and methods : Sixty patients were selected for treatment, and signed a detailed informed consent. Diagnosis of TTH was posed with the criteria advocated by the International Headache Society. Twenty-eight patients were males. Patients were randomised in three groups of 20 patients (A, B, and C). All the groups received 80–150 IU BoNT/A: Group A was injected at fixed points, Group B was injected with a “follow the pain” pattern, determining together with the patient the optimal points for injection. Group C was treated with the “follow the pain” feature plus a dedicated exercise program. Results were evaluated considering “verbal rating” scale (VRS), registering any improvement of symptoms severity. Results : After 3 months of treatment, 9 out of the 20 patients included in Group A (45%), 13 in Group B (65%) and 16 (80%) in Group C documented an improvement of their symptoms at the VRS. These differences reached statistical significance, and also drug intake (mainly NSAIDs and tricyclic agents) was diminished during the study period (although not reaching statistically significant difference among the three groups). Conclusions : BoNT/A injection may be a valid treatment modality for TTH, especially when combined to adjunctive physiotherapy, and when using a “follow the pain” pattern of injection. However, in order to obtain this treatment modality, a dedicated follow-up of the patient by an experienced operator is necessary.