Analysis of the clinical course of non-Jewish, autosomal dominant torsion dystonia.

We have analyzed the clinical course of non-Jewish, autosomal dominant torsion dystonia in 41 patients among 15 families. The median age of onset was 8 years, with a range of 0.8-57 years. The body regions most frequently affected at the onset were the legs and arms. There was a relationship between age of onset and site of onset; at earlier ages the legs were more frequently affected, whereas at later ages, the arms and cranial structures were more frequently affected. Fifty-three percent of patients developed generalized dystonia within a median time of 1 year. Two factors strongly associated with the occurrence of generalized dystonia are: early age of onset, and onset in the legs. Our results are similar to those of prior studies of non-Jewish and Jewish patients with torsion dystonia. Whether there are clinical distinctions between the Jewish and non-Jewish forms of dystonia, as proposed in the past, must be reinvestigated in patients within the same referral base.