The first thing I learned when I started my psychiatry training in the early 1990s was how to test for tardive dyskinesia (TD), one of the most important side effects of psychiatric medications. Tardive dyskinesia is an abnormal movement disorder that can develop from long term antipsychotic medication use and can ultimately become disabling. Back then, there was no effective treatment for TD but we would do a five-minute clinical exam (Abnormal Involuntary Movement Scale or AIMS examination) every 6 months to monitor for any changes and if necessary reduce the dose or stop the medication altogether. At that time, the older antipsychotics carried a 4% risk of TD for every year a patient was on this type of medication and was considered possibly irreversible. There was hope this problem would be mitigated when the second generation antipsychotics became available in the mid 1990s which is what happened as the risk was reduced by one third compared to the first generation but that still left many patients with TD. In fact, five million people in the U.S. are currently treated with antipsychotics and 600,000 of those may have TD. Fortunately, the tide started to turn in 2017 when the FDA approved two medications that are both effective for treating TD. In this article, I will review what to look for in recognizing abnormal movements and the challenges of using telehealth to find and treat TD.
Who can recognize an abnormal movement? The answer is anybody especially in this pandemic era. That could be the patient, family, caregivers, or friends. As a psychiatrist, the best way to monitor for TD is using an in-person exam where I can specifically use the AIMS to each area of the body and assess how the patient is walking. Of course, this test has become more difficult if the patient is wearing a face mask. Moreover, when the pandemic began in 2020 that changed the screening procedure to mostly either video or phone. An effective video assessment includes the right equipment (a laptop rather than a phone), right environment (a well-lit room in a chair without armrests), and a helping hand (a companion to tilt the camera to better see the feet and toes). Video is obviously preferred but isn’t always possible. While telephone sessions are not ideal as this is a visual assessment, I found it possible to play detective by using pointed questions such as: do you have any difficulty putting on makeup, putting away glasses or writing? Or has someone commented that you move funny or request that you stop moving when you really have no control? Are you embarrassed to go out in public because of your movements? How do the movements make you feel? The other strategy I used is to get collateral information from caregivers or family members and not just from the patient. It became clear to me that anyone can recognize abnormal movements and that has been very helpful in figuring what may be occurring.
It’s important to know that there are four general categories of movement disorders in people taking antipsychotics of which TD is one of them. The other three are dystonia, akathisia, and parkinsonism. Dystonia can develop hours to days after starting an antipsychotic medication and can take the form of pulling, twisting, sustained and repetitive movements or postures. Risk factors for developing dystonia include a young age (teenagers), male gender, and intramuscular administration. Dystonia can also be caused by genetic conditions and cerebral palsy. Acute dystonia may be helped by high dose anticholinergic medications like Benadryl but a common strategy in psychiatry is the prophylactic use of anticholinergics when starting certain antipsychotic medications.
Akathisia can begin within days to months of starting an antipsychotic and can be described as an inner feeling of restlessness with the urge to move and inability to stay seated. There is a voluntary aspect to akathisia as often times a person can suppress the movement if asked to. Risk factors include being female, older age, mood disorder and iron deficiency. Treatment of akathisia includes decreasing the dose of antipsychotic medication or adding a beta-blocker or benzodiazepine.
Parkinsonism can be noticed days to weeks to years after starting an antipsychotic and consists of a tremor, rigidity, and slowness of movement. The tremor in parkinsonism is much more rhythmic and continuous than in TD. Another common feature of parkinsonism is called micrographia in which there is a change in how a person writes words using a much smaller print; this feature can be used clinically by comparing a patient’s signature before and after starting an antipsychotic medication. Risk factors include older age, females and dementia. Treatment usually involves lowering the dose of antipsychotic medication or adding an anticholinergic agent.
TD is rarely seen until three to six months after starting the antipsychotic to years later and may cause involuntary movements of hands (“piano playing”), feet (“foot tapping”), trunk, arms, legs, neck and face. Facial movements may include the muscles of the face, lids and tongue. These movements can be sinuous or jerky, and are non-rhythmic in nature. Tremors are not a typical symptom of TD. The disorder is most often seen in the face including grimacing, facial tics, lip smacking, chewing, and wormlike movements of the tongue. Risk factors for TD include older age, female sex, longer duration of treatment, mood disorder rather than schizophrenia, substance abuse, and acute neurological side effects of antipsychotics mentioned above such as tremor, rigidity, and akathisia. First line treatment for TD is a class of medication called VMAT2 inhibitors. It’s important to note that a person can remain on their antipsychotic medication when taking a VMAT2 inhibitor.
If you are interested in being able to recognize how to distinguish between these 4 different abnormal movements, here is a link to a 3 minute video that summarizes the major differences:
Unfortunately, it’s not always easy in some cases to tell the difference between TD and the other antipsychotic induced movements and a person can have more than one kind of movement at a time. Obviously, it’s crucial to make those distinctions because each disorder requires specific management. Finally, these movement disorders can be disfiguring, stigmatizing, and may influence compliance, relapse, and rehospitalization but we now have good treatments for all of them. TD is not just a movement disorder but there are also psychological and social aspects as well such as when patients have negative feelings towards their body they perceive as betraying them with abnormal movements that may limit their willingness to go out in public. If you or someone you know may be struggling with this issue, please make them aware there are new treatments available for TD that may greatly improve the quality of their life if brought to medical attention.