Tardive Dystonia Clinical Presentation

Tardive dystonia starts insidiously and progresses over months or years, until it becomes static.

• Young male psychiatric patients commonly develop tardive dystonia after variable periods (weeks or years) of exposure to dopamine antagonists.
• In most patients, tardive dystonia begins in the face or neck; less commonly, the dystonia may begin in one of the arms and, rarely, as a focal foot dystonia.
• In 1992, Burke et al conducted a study of patients at the time of maximum severity of their illness.^[16] Most patients had involvement of cranial nerves. The neck was involved in almost 80% of the cases; retrocollis was characteristic, occurring in 50% of those with neck involvement. The trunk was affected in 35% of the patients, and most of them had back-arching movements. The arms were affected in 42% of the patients, often in the form of sustained extension to the elbow, especially when walking. The legs were affected in a minority of patients. According to Burke et al, the diagnosis of tardive dystonia requires the following 4 criteria:

  • The patient must have dystonic movements defined as sustained muscle contractions, frequently causing twisting and repetitive movements or abnormal postures.
  • The dystonia must develop either during or within 3 months of a course of neuroleptic treatment. The 3-month cutoff recognizes the fact that neuroleptics may suppress tardive dyskinesia, which often does not become apparent until some time after drugs are stopped.
  • No other neurologic signs should be present to suggest one of the many known causes of secondary dystonia, such as Wilson disease.
  • The patient must have a negative family history for dystonia. In the presence of a positive family history, knowing whether the affected individual has neuroleptic-induced dystonia or simply expresses an inherited form that is coincident with neuroleptic use is not possible.
• A history of recent trauma in the same body region as the focal dystonia or head trauma suggests a posttraumatic dystonia. Hemidystonia is almost always related to a brain lesion on the contralateral side of the abnormal movements.

The movements evident in patients with tardive dystonia are not dissimilar to those observed in patients with primary torsion dystonia. Dystonic movements can be focal, segmental, generalized, multifocal, or hemidystonic (as described in the Introduction).

A detailed movement disorders examination should be performed. This should include an evaluation for dystonia and abnormal movement disorders such as dyskinesias, parkinsonism, and akathisia. Please see the case described in the Introduction as a sample of how this could be done.

For those unfamiliar with the examination of dystonia, it may be helpful to review the common research rating scales used for this condition and ensure that the examination includes all the basic points mentioned in the scales. A resource for the most commonly used scales can be found online at Movement Disorder Virtual University.

Some helpful tips while examining a patient with dystonia are as follows:

• A video tape of the examination is helpful so that subsequent examinations can be compared.
• Dystonia typically presents in a twisting pattern with deviations on multiple anatomical planes. For instance, torticollis usually presents with both a deviation to one side as well as a head tilt. A hand dystonia often presents with an ulnar deviation as well as fingers in flexion or extension. This twisting pattern can be stable or more dynamic in an athetoid pattern.
• Dystonia can present with a tremor. One helpful hint in identifying a tremor as dystonic is if it resolves when the patient is asked to allow their affected body part to go into the position that the dystonia is trying to make it go (ie, not fight the movement). Although it does not rule out a dystonic tremor if it does not go away with this maneuver, it is pathognomonic if it does resolve.
• Dystonia frequently presents with a sensory trick or geste antagonist. This involves a point on the body where sensory stimulation can frequently overcome or reduce the dystonic symptoms. For instance, patients with torticollis (dystonic neck rotation) frequently find that pressure on their chin or sides of their face can cause the dystonic movements to subside. Patients with jaw or lingual dystonia may find that holding a straw or toothpick inside their mouth helps to reduce their symptoms. These tricks can be helpful diagnostically, but also can be used in developing treatment plans.
• Dystonia can be surprisingly task specific. For instance, symptoms can occur with speech but resolve with silence or occur while walking but resolve with running or walking backwards. Again, this can be used to assist with diagnosis and occasionally in developing nonpharmacologic treatment strategies.

A routine physical and neurologic examination should also be included, with an ophthalmologic examination with a slit-lamp if indicated, to look for other symptoms. If general physical examination signs or neurologic signs other than dystonia are present, then tardive dystonia may be associated with other pathologic conditions, because neuroleptics do not induce progressive changes in intellect, such as sensory function, pyramidal motor systems, and cerebellar function.

A mental status examination should be performed, but the results can be completely normal since tardive dystonia does not indicate a psychiatric disease. It is merely a secondary dystonia and any patient who takes a dopamine receptor blocker chronically for any reason (including patients taking antinausea medications) can develop this condition. Given that this is a neurologic and not a psychiatric condition, the mental status examination is not helpful for diagnostic purposes and is most useful in determining whether a patient needs to remain on dopamine blocking agents or can be weaned off.

Again, please see the case described in the introduction for a detailed example of how a physical and mental status examination can be done.

Young age, male sex, mental retardation, and convulsive therapy have been identified as specific risk factors. Exposure to dopamine receptor blocking agents (DRBAs) is essential for the diagnosis of this disorder. Neuroleptic exposure is the most significant etiologic factor. Other medications associated with tardive dystonia include antiemetics (eg, prochlorperazine, promethazine, metoclopramide) and antidepressants (eg, amoxapine). Also, single case reports for veralipride, a benzamide derivative, and lithium causing dystonia have been reported.

• Neuroleptics

  • The most common cause of tardive dystonia is neuroleptic exposure. Tardive dystonia develops in a shorter period and with significantly less total neuroleptic exposure than severe tardive dyskinesia. Also, patients with tardive dystonia seem to receive fewer doses of neuroleptic agents than persons who develop tardive dyskinesia.
  • All dopamine receptor antagonists that reportedly cause oral tardive dyskinesia also reportedly cause tardive dystonia. These include all typical and atypical agents.
  • The duration of exposure to antipsychotics required to cause tardive dystonia ranges from months to years. Exposure to antipsychotics need not be long, and a minimum safe period is not apparent. This duration of neuroleptic exposure seems to be shorter for women. A longer duration of exposure to neuroleptics does not correlate with the severity of dystonia; however, patients with generalized dystonia have shorter neuroleptic exposure than patients with focal dystonia.
• Antidepressants

  • Amoxapine, an antidepressant with dopamine receptor–blocking properties, has been implicated in cases of tardive dystonia.
  • In 1997, Vandel et al reviewed the literature and found that tricyclic antidepressants induced extrapyramidal symptoms, including tardive dyskinesia, tardive dystonia, myoclonus, and akathisia.^[17]
• Antiemetics

  • Several antiemetics with dopamine receptor–blocking properties have also been associated with tardive dystonia.
  • These include prochlorperazine, promethazine, and metoclopramide.
• Veralipride: In 1992, Gabellini et al reported 1 case of tardive dystonia caused by a veralipride, a benzamide derivative.^[18]
• Lithium: In 2002, Chakrabarti and Chand reported on a patient with bipolar disorder, with no exposure to neuroleptics for at least 3 years, who developed tardive dystonia while on lithium 800 mg/d and a small dose of carbamazepine 100 mg/d, and improved with cessation of these medications and the eventual addition of clozapine. Given the case reports of lithium causing tardive dyskinesia, they speculate that this was a case of either lithium-induced tardive dystonia or a result of the mixture of lithium and carbamazepine.^[19]