Dystonia in progressive supranuclear palsy.

OBJECTIVES: To document the nature, distribution, and frequency of dystonic symptoms in progressive supranuclear palsy (PSP).
METHODS: Charts and videotapes of all clinically diagnosed patients with PSP seen between 1983 and 1993 were reviewed and the occurrence, nature, and distribution of all dystonic symptoms were recorded.
RESULTS: Of 83 identified cases 38 had some dystonic features. Twenty (24%) had blepharospasm (one was induced by levodopa), 22 (27%) had limb dystonia (one was induced by electroconvulsive therapy and another by levodopa), 14 (17%) had axial dystonia in extension, one had oromandibular dystonia induced by levodopa, and two had other cranial dystonias. Six patients had limb dystonia as an early or presenting feature, sometimes leading to misdiagnosis of cortical-basal ganglionic degeneration. All three patients who had postmortem confirmation of the diagnosis had other concurrent disease. One patient with bilateral limb dystonia and blepharospasm had evidence of previous hydrocephalus and severe arteriosclerotic changes. One with arm dystonia also had cerebrovascular disease and one with hemidystonia also had rare swollen chromatolytic neurons in the frontotemporal cortex.
CONCLUSIONS: Dystonia is a common manifestation of PSP. Limb dystonia is particularly common and may indicate the presence of concurrent disease. When dystonia occurs in PSP, dopaminergic medication should be cautiously reduced or discontinued to rule out the possibility of treatment induced symptoms.