Long-term quality of life in cervical dystonia after treatment with abobotulinum toxin A: a 2-year prospective study

Background: The short-term quality of life (QoL) in cervical dystonia (CD) after treating with abobotulinum toxin A (Abo-BTX A) and neubotulinum toxin A (Neu-BTX A) have been studied in Thai CD patients. However; the long-term study has not been published. Objective: The aim of the present study was to determine long-term improvement of the health-related quality of life (HRQoL) after eight injections of Abo-BTX A over 2 years in CD patients. Patients and methods: A 2-year prospective study on the QoL of CD patients, as measured by HRQoL, before and after receiving eight injections of Abo-BTX A at 3-month intervals over a 2-year treatment period was performed. The disease-specific HRQoL was assessed before and after the treatment by using the Cervical Dystonia Impact Profile-58 (CDIP-58) questionnaire. The general HRQoL was assessed by using the Medical Outcomes 36-Item Short Form Health Survey (SF-36), while depressive disorder screening was assessed by using the Center of Epidemiologic Studies-Depression (CES-D) questionnaire. The SF-36 and CES-D questionnaire were administered before treatment and every 3 months before the next injection for a 2-year period. Results: A total of 20 CD patients were enrolled from January 2013 to December 2015. CDIP-58 showed a significant improvement after long-term injections of Abo-BTX A in all domains (P < 0.001). However, only vitality domain of SF-36, which assessed general HRQoL, showed a significant improvement after long-term injections (P = 0.037). There was no prevalence of depressive disorder in all patients (CES-D score < 20) in this study. Conclusion: The Abo-BTX A injections at 3-month intervals over a 2-year period improved the CDIP-58 scores, which assess disease-specific HRQoL, as well as an increased vitality domain of general HRQoL. No patient suffered from depression in this study.