Describe the longitudinal effect of repeated botulinum toxin A (BoNT-A) injections on patient-centered goal attainment for patients who have had ≥4 injection cycles.
Primary effectiveness results from the ULIS-3 study demonstrated that, at the population level, most patients achieved their treatment goals as expected (mean cumulated Goal Attainment Scale [GAS] T score at 2 years was 49.5 [49.1, 49.9]). However, the longitudinal evolution of patient-level goal attainment over each consecutive cycle has been less well-studied.
Secondary analysis of patient level data from the prospective, observational, ULIS-3 study (NCT02454803) which followed adult patients over 2 years of spasticity management with BoNT-A (any commercially available product). Data were analyzed for the 538 patients who received ≥4 injection cycles of BoNT-A and underwent ≥1 one GAS assessment for each of the first four injection cycles. Potential predictors (including baseline demographics, clinical characteristics, and treatment parameters) of GAS T score across the 4 cycles were analyzed using a multivariate linear regression model.
Mean GAS change scores slightly decreased over repeated treatment (mean [95%CI] changes of 13.01 [12.36, 13.65] for Cycle 1, 12.63 [12.01, 13.24] for Cycle 2, 11.81 [11.26, 12.36] for Cycle 3 and 11.62 [11.06, 12.18] for Cycle 4) but remained above the minimal clinically difference of 10. Patients who were injected under guidance for at least 3 of the 4 cycles were significantly more improved in terms of change in GAS T Score at each cycle versus those in whom guidance was not used (mean [95%CI] treatment difference of 1.86 [0.98, 2.75], p<0.0001).
Treatment with BoNT-A was consistently effective in helping patients with upper limb spasticity to achieve their treatment goals over four consecutive cycles. Multivariate analysis demonstrated the importance of using appropriate injection guidance techniques.