Oromandibular Dystonia: Demographics and Clinical Data from 240 Patients.

OBJECTIVE: To report demographic data from a large cohort of patients with oromandibular dystonia (OMD). METHODS: This is a retrospective review of patients with OMD referred to our institution between 1989 and 2015. Demographic (age of onset, gender, and familial history of dystonia) and clinical (type of OMD, associated dystonia, and etiology of dystonia) data were collected from a cohort of 240 individuals. RESULTS: The mean age of onset of OMD was 51.6 years old, with a female predominance (2:1). A family history of dystonia was found in 6 patients (2.5%). One hundred and forty-nine patients (62.1%) had the jaw-opening type of OMD, 48 patients (20.0%) had the jaw-closing type, and 43 patients (17.9%) had a mixed form of OMD. Lingual dystonia was also present in 64 (26.7%) of these patients. Eighty-two patients (34.2%) had a focal dystonia, 131 patients (54.6%) had a segmental dystonia, and 27 patients (11.3%) had a generalized dystonia. One hundred and seventy-one patients (71.3%) had idiopathic OMD. CONCLUSION: OMD is a chronic and disabling focal dystonia. Our study found a prevalence of female patients, an onset in middle age and a predominantly idiopathic etiology. Unlike other studies, jaw-opening was found to be the most frequent clinical type of OMD.