Factors affecting the health-related quality of life of patients with cervical dystonia and the impact of botulinum toxin type A injections

The purpose of this study was to analyze the health-related quality of life (HRQL) of patients with cervical dystonia (CD) and the impact of botulinum toxin A (BTX-A) therapy in these patients. The authors recruited 101 patients with CD, all previously treated with BTX-A. Both before and 4 weeks after injection of BTX-A the patients were assessed using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS), a Visual Analogue Scale for pain (VAS: 0-100%), the Short Form 36 health survey questionnaire (SF-36), and the Montgomery-Asberg Depression Rating Scale (MADRS). A control group of 84 healthy volunteers was also evaluated. The patients' baseline SF-36 scores were worse in all the domains when compared with those of the controls. Depression was found in 47.5% of the patients. Improvements were noticed 4 weeks after the single BTX-A injections in all the SF-36 domains, and in the VAS, TWSTRS and MADRS scores. The TWSTRS results did not correlate with any of the SF-36 subscores. Stepwise backward regression analysis revealed depression as the main predictor of poor HRQL, as well as female sex, poor financial situation, and living alone. On contrary, longer treatment with BTX-A was associated with better scores. Cervical dystonia has a marked impact on HRQL and treatment with BTX-A injections has a beneficial effect, seen both in objective and in subjective measures. Depression in CD patients is a main predictor of worse HROL.