Cervical dystonia and pain: characteristics and treatment patterns from CD PROBE (Cervical Dystonia Patient Registry for Observation of OnabotulinumtoxinA Efficacy)

Abstract

To compare profiles of subjects with and without cervical dystonia (CD)-associated pain, to evaluate the contribution of pain and the motor component of CD on quality of life, and to compare the initial botulinum toxin treatment paradigm between pain groups, baseline data were used from the CD Patient Registry for Observation of OnabotulinumtoxinA Efficacy (CD PROBE), a multicenter, prospective, observational registry designed to capture real-world practices and outcomes for onabotulinumtoxinA CD treatment. Subjects were divided into no/mild pain [Pain Numeric Rating Scale (PNRS) score 0-3] and moderate/severe pain groups (PNRS score 4-10). Descriptive and differential statistics were utilized to compare groups. 1,037 subjects completed the first treatment session, reported baseline botulinum toxin status, and completed baseline PNRS. Those with no/mild pain were significantly older at baseline. Those subjects with moderate/severe pain had higher Toronto Western Spasmodic Torticollis Rating Scale Severity (17.7 ± 5.1 vs. 16.2 ± 5.6, p < 0.0001) and Disability (12.7 ± 6.1 vs. 7.5 ± 5.6, p < 0.0001). CD subjects with moderate/severe pain received a higher mean dose (177.3 ± 82.9 vs. 158.0 ± 67.1 U, p = 0.0001) of onabotulinumtoxinA and were injected in more muscles (4.1 ± 1.4 vs. 3.7 ± 1.2, p < 0.0001) at initial treatment. CD PROBE clearly demonstrates the frequency of pain in CD and substantiates its importance when determining an optimal treatment paradigm. Future analyses of CD PROBE will further our understanding of the treatment patterns and outcomes related to onabotulinumtoxinA therapy for this disabling condition.

Fig. 1

Effects of pain group, age, and gender on the a probability of work being stopped due to CD and b the probability of employment status being affected by CD. Patients had to be employed at time of CD diagnosis for these logistic regression models. CD cervical dystonia

Fig. 2

Influence of TWSTRS Severity score and PNRS score on CDIP-58 subscale scores. Lindeman–Merenda–Gold estimates and a piecewise natural cubic spline were used to generate each 3D perspective plot. Dashed line indicates the front of the cube for each plot; CDIP-58 Cervical Dystonia Impact Profile-58, PNRS Pain Numeric Rating Scale, TWSTRS Toronto Western Spasmodic Torticollis Rating Scale