Onabotulinumtoxin A for the management of chronic migraine in current clinical practice: results of a survey of sixty-three Italian headache centers

Background: Chronic migraine is a complex clinical condition often undertreated. Onabotulinumtoxin A (OBT-A) was approved in Italy in 2013 for symptom relief in patients with chronic migraine who have failed, or do not tolerate, oral prophylactic treatments. However, the impact of OBT-A in clinical practice remains to be defined. Methods: To investigate the current management of chronic migraine with OBT-A in clinical practice, a web-based survey was conducted among clinicians working in third-level headache centers across Italy. A 26-item questionnaire was designed and developed by a group of 10 Italian headache specialists to address the following issues: treatment paradigm and OBT-A injection intervals, frequency of treatment and retreatment, definition of responders/non-responders, satisfaction with treatment potential impact of early treatment with OBT-A. Ninety-six headache centers were selected and contacted via e-mail. The online survey was anonymous and carried out using a secure website. Results: Overall, 64 of the 96 centers (66.7%) completed the questionnaire. Most centers (98.4%) had been using OBT-A for >1 year. OBT-A was administered according to the PREEMPT paradigm in most centers (88.9%). While during the first year of prophylaxis with OBT-A most clinicians (93.6%) repeated OBT-A treatment every 3 months, as recommended, in the following years interval duration was variable. Response to OBT-A was defined as a ≥ 50% reduction in the headache days by 58.7% of the clinicians, and as a ≥ 30% reduction by 25.4% of them. Almost 60% of the clinicians considered OBT-A as a long-lasting therapy, while for one-third of them treatment could be discontinued in patients showing a benefit for ≥6 months. According to 80% of the clinicians, early administration of OBT-A after the onset of chronic migraine was associated with better outcomes, and 47.6% felt that OBT-A should be recommended as a first-line option. Conclusions: This survey indicates that in third-level headache centers in Italy OBT-A is used in good compliance with current recommendations. There is agreement about the definition of response as a reduction in headache days by 30% to 50%. Additional effort is required to define response to OBT-A and to establish optimal treatment duration.