Real-world experience with botulinum toxin A for the treatment of hemifacial spasm: A study of 1138 injections.

[BACKGROUND] Hemifacial spasm (HFS) is a chronic, potentially disabling disorder that often requires long-term management with botulinum toxin (BoNT). In a country where healthcare costs limit compliance to medical follow-up and treatment, the study aims to provide a real-world experience on the use of BoNT for HFS among Filipinos.

[METHODS] We retrospectively collected data from 162 HFS patients who received 1138 botulinum toxin (BoNT) injections from 2006 to 2019 in our movement disorders center in the Philippines. We described their clinical profile and treatment response.

[RESULTS] The mean age at onset of disease was 47.7 ± 10.72 years. Majority of the patients reported a baseline moderate disease severity and disease frequency of >75% of waking time (59.8% and 46.9%, respectively). Most patients (61.73%) received 5 or less injections during the follow-up period. The mean duration of follow-up was 2.96 ± 4.28 years. The overall duration of treatment effect per injection was 3.6 ± 1.3 months while the mean interval between injections was 6 ± 5 months. There was no difference in the symptom improvement and duration between onabotulinumtoxinA and abobotulinumtoxinA. Side effects were infrequent.

[CONCLUSION] This study supports existing evidence on the efficacy and safety of BoNT for the symptomatic relief of HFS. In the Philippines, long-term treatment with BoNT may be limited by the cost of the procedure as majority of our patients had a few injections with long treatment intervals.