Patient Perceptions of a Preventive Effect of Long-Term Botulinum Neurotoxin Therapy in Cervical Dystonia.

Patients with cervical dystonia (CD) often believe that disease severity would have progressed beyond the pre-treatment level if botulinum neurotoxin (BoNT) therapy had not been initiated. The aim of the present study was to assess the perceptions of long-term BoNT-treated patients with CD regarding the expected course of disease severity over the next 10 years under the hypothetical assumption that BoNT therapy is discontinued. Fifty patients with idiopathic CD receiving long-term BoNT therapy were screened, and 43 patients were included. Disease severity at the day of recruitment was assessed as a percentage of CD severity at the onset of BoNT therapy (PAS-%). Patients also generated, in a standardized manner, a graph illustrating the development of CD severity since initiation of BoNT therapy. Subsequently, patients estimated the expected severity of CD after 10 years, expressed as a percentage of severity at BoNT therapy onset (PAS-STD), under the hypothetical assumption that BoNT therapy was discontinued at the time of recruitment. They additionally drew a graph depicting the anticipated progression of CD severity over the subsequent 10 years under this assumption. Furthermore, 33 of these 43 patients had previously assessed the expected development of CD severity under the assumption that no BoNT therapy had ever been performed (PAS-NO%) in an earlier study. Mean PAS-STD was significantly higher than mean PAS-% (