Headache attributed to craniocervical dystonia: A prospective cohort study.

[BACKGROUND] Cervical dystonia is the most common form of focal idiopathic dystonia and is frequently associated with pain. Headaches are not considered to be more prevalent among patients presenting with cervical dystonia, and headaches attributed to craniocervical dystonia are considered to be a rare disorder, despite the lack of studies and clinical information regarding the subject.

[OBJECTIVES] To investigate the prevalence, characteristics and impact of headaches attributed to craniocervical dystonia in cervical dystonia patients receiving treatment with botulinum toxin type-A (BoT-A).

[METHODS] Twenty-four patients presenting with cervical dystonia were assessed before receiving their scheduled BoNT-A injections and then again approximately 4 and 16 weeks after, regarding the clinical characteristics of their dystonia and headaches. Headaches were classified in accordance with the current International Classification of Headache Disorders. We used the Short Form-36 Health Survey, Hospital Anxiety and Depression Scale, Headache Impact Test-6, Toronto Western Spasmodic Torticollis Rating Scale and McGill Pain Questionnaire.

[RESULTS] Nineteen patients (79.1%) presented with cervical dystonia associated with pain and 18 (75.0%) with headaches. The prevalence of headaches attributed to craniocervical dystonia was 29.2%; HIT-6: 60.1 ± 9.9. Patients with headaches presented significantly poorer TWSTRS pain scores, compared to patients with no headaches. Those with headaches attributed to craniocervical dystonia presented with more disability and demonstrated a significant improvement in the impact of headaches after BoNT-A injections, together with an improvement in the dystonia.

[CONCLUSIONS] Headaches are highly prevalent amongst cervical dystonia patients, have an impact on their quality of life and improves after BoNT-A injections.

[SIGNIFICANCE] We found that headaches are more frequent among patients with cervical dystonia than previously thought, and that they contribute towards an overall increase in pain in these patients. Headaches attributed to craniocervical dystonia are associated with greater disability among patients with cervical dystonia. These headaches improve after botulinum toxin injections, in parallel with the improvement of cervical dystonia symptoms.