[Treatment satisfaction in patients with cervical dystonia : Subgroup analysis of INTEREST-IN-CD-2].

Background: Even though treatment guidelines recommend botulinum neurotoxin A (BoNT-A) as first line treatment for primary cervical dystonia (CD), there are only limited data on how BoNT-A-injections are administered in routine clinical practice.

Objective: This subgroup analysis evaluated patient satisfaction and symptom control under consideration of BoNT‑A treatment modalities in German and Austrian CD patients (DE/AT, n = 79) compared to the full international cohort (n = 995).

Material And Methods: The INTEREST-IN-CD2 was a prospective, multicenter, longitudinal observational study. Course of treatment in adult primary CD patients under BoNT‑A treatment was assessed over a time period of 3 years. Primary outcome measure was the long-term satisfaction of patients with treatment, measured as maximum satisfaction between two consecutive injections as well as satisfaction at the time of reinjection.

Results: Treatment satisfaction at the maximum effect was stable and comparably good in both populations during the study (82.3-92.7% and 85.0-89.9%). Satisfaction decreased with decreasing BoNT‑A effect at the end of the treatment interval: it was comparable at the start of the study in both groups (54.2% vs. 51.4%), decreased numerically in the DE/AT group to 32.7% but remained stable in the total population. Analysis of Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) and Tsui scores did not reveal any substantial differences between the DE/AT subgroup and total cohort.

Conclusion: Overall, the study confirmed good clinical symptom control by BoNT‑A. The numerical differences in the current satisfaction seen in the comparison of DE/AT to the total cohort are possibly due to different proportions of BoNT‑A naïve patients in both groups, as they expressed different levels of satisfaction than previously treated patients.