Objective: To investigate the long-term efficacy and safety of a botulinum toxin type A (BoNT-A) for the treatment of cervical dystonia (CD).
Methods: We conducted a retrospective chart review of patients with CD treated with abobotulinumtoxinA (Dysport™ 100-800 units [U] for injection) between 1993 and 2009 at the University Hospital "La Paz" (LPUH). Affected muscles were selected using electromyography (EMG).
Results: Thirty-seven patients were included in the study; most were female (62%) and had idiopathic CD (60%). Almost half (46%) of patients were diagnosed with the condition more than 10 years ago. The most common clinical presentations of CD were rotation (46%) and laterocollis (43%). On average, patients were treated with Dysport for 7 years (range: 1-17 years) and received 487 (range: 320 to 650) U over 15.9 (range: 1 to 40) injection cycles. Most (97%) patients maintained a response from treatment initiation to end of evaluation period. Overall, 70% of patients were taking concomitant oral medication. Dysport was generally well tolerated. Dysphagia was reported by 18.9% of patients, but this did not lead to discontinuation of Dysport treatment.
Conclusion: These data confirm the long-term efficacy and safety of Dysport in CD over a period of up to 17 years.