Long‐term follow‐up of cervical dystonia patients treated with botulinum toxin A

Abstract
We followed the course in 100 consecutive patients with cervical dystonia (CD) after they were initially treated with botulinum toxin (BTX) in the form of Dysport 10 to 12 years ago. A total of 4 patients had died, and 6 were lost to follow‐up. Of the remaining 90 patients, 57 (63%) were still treated with BTX. In the patients treated at one centre over the whole period with Dysport, mean dose used during each treatment session was 833 (SD ± 339) units Dysport with a cumulative dose of 20,943 (SD ± 9462) units Dysport over a mean of 26.8 (SD ± 8.6) treatment cycles. Secondary nonresponse was detected in 3 of the 90 patients. During follow‐up, 12 patients developed blepharospasm, 13 oromandibular dystonia, and 17 patients writer's cramp. We conclude that BTX remains effective and safe for approximately 60% of CD patients for more than 10 years. © 2003 Movement Disorder Society