Health related quality of life is improved by botulinum neurotoxin type A in long term treated patients with focal dystonia

Objectives-The advent of botulinum neurotoxin type A (BoNT/A) gave rise to substantial progress in the treatment of focal dystonias. In the light of t he high costs of the toxin and the necessity to establish valid outcome ind ices for this treatment apart from sheer reduction of dystonic muscle tone and posture, the impact of focal dystonia and its treatment with BoNT/A on patients' health related quality of life (HRQL) was determined. Methods-Fifty patients with cranial and cervical dystonia treated long term with BoNT/A were enrolled in a prospective, open labelled cohort study. Th e HRQL was assessed using the EuroQo1 (EQ-5D) and the short form 36 health survey questionnaire (SF-36) at baseline before BoNT/A injections and at tw o follow up visits after 6 and 12 weeks covering one BoNT/A treatment perio d with maximum effect size at the first follow up. Results-Compared with a general population sample, a considerable negative impact of focal dystonia on HRQL was found in patients under investigation. In both disease types, BoNT/A treatment led to a significant improvement i n several HRQL dimensions, in particular providing moderate to marked effec t sizes in the fields of mental health and pain. The impairment of HRQL due to pain as well as the BoNT/A induced improvement within this SF-36 subsco re were significantly higher in patients with cervical dystonia. Under BoNT /A therapy, no correlation was found between changes of clinical outcome sc ores and HRQL measures. Conclusions-The data confirm that BoNT/A is able to induce a significant, b ut temporary amelioration of several aspects of HRQL in both types of focal dystonia. This may substantially contribute to the patients' subjective be nefit from the therapy. Moreover, the data provide further arguments to acc ept high costs of the BoNT/A treatment in these severely handicapped patien ts, as a consequence of its considerable benefit on quality of life.