Elevated plasma levels of homocysteine in dystonia

OBJECTIVE: Several case reports with dystonia and homocysteinuria suggest a putative pathogenetic importance of homocysteine for the development of dystonia. We investigated relations between plasma homocysteine, age, severity and duration of primary idiopathic torsion dystonia. SUBJECTS AND METHODS: We measured homocysteine levels in blood samples drawn from 24 subjects with dystonia and controls. RESULTS: Patients with dystonia (19.3 +/- 8.5, range 8.4-37 micromol/l) showed significantly (P= 0.008, t-test) increased levels of total homocysteine compared with age- and sex-matched controls (13.9 +/- 4.2, range 5.8-24.5 micromol/l). No significant influence of age and duration of dystonia appeared, but we found a significant trend for an association between severity of dystonia and homocysteine (P = 0.046, R = 0.41). CONCLUSIONS: Our study supports previous reports on subjects with dystonia with homocysteinuria. Neurotoxic effects and N-methyl-D-aspartate agonistic properties of homocysteine may hypothetically contribute to onset and severity of dystonia.