[Predictive factors of the response to treatment with onabotulinumtoxinA in refractory migraine]

Abstract

Aim: To identify the clinical features that predict a favourable response to onabotulinumtoxinA (OnabotA) treatment in patients with refractory migraine.

Patients and methods: Retrospective analysis of patients with refractory migraine who underwent at least two pericranial injections of OnabotA between 2008 and 2012. Patients were divided into responders and non-responders. Some clinical features including unilateral location of headache, presence of pericranial muscle tension, type of pain (imploding or exploding), duration of migraine (less than or greater than 10 years) and medication overuse were compared between the two groups.

Results: 39 patients were included (35 women) with a mean age of 46 years. 18 patients (46.2%) showed a greater than 50% reduction in the number of headache days/month (responders). When analyzing the different features of migraine, we observed that all were equally prevalent in responders and non-responders (p > 0.05): unilateral location (66.7% vs 66.6% respectively), implosive pain (27.8% vs 38.1%), presence of pericranial muscle tension (33.3% vs 38.1%), duration of migraine more than 10 years (77.8% vs 69.2%) and presence of medication overuse (50% vs 81%).

Conclusion: We failed to identify any clinical feature in our patients with refractory migraine that predicts a favourable response to OnabotA treatment.