WASHINGTON – Neurologists vary widely in their practices and beliefs when it comes to diagnosing and managing patients with psychogenic movement disorders, and those ranges might be indicative of the absence of practice guidelines, according to results from more than 500 Movement Disorder Society members.
The findings revealed a range of approaches in the use of diagnostic testing in making and delivering the diagnosis, and low confidence in the effectiveness of any therapy.
“This is a starting point to determine areas of weaknesses in the diagnostic process and in treatment strategies,” said Dr. Alberto J. Espay, one of the investigators.
Psychogenic movement disorders (PMDs) are mostly generated by conversion or somatoform disorders in which psychological stressors unconsciously produce abnormal movements. They have no known “organic” etiology and may occur in association with underlying psychiatric disease.
Estimates put the number of PMD patients at about 1%-2% of the patient population at general neurology practices, but tertiary movement disorder referral centers have reported as many as 25% of their patients have a PMD, said Dr. Espay, a movement disorders specialist at the University of Cincinnati.
PMDs have been a neglected area of study “because it's so hard to have patients accept the psychological underpinnings of their problem [while] at the same time not stigmatizing them,” said Dr. Espay, who presented the survey results at the Second International Conference on Psychogenic Movement Disorders and Other Conversion Disorders, which was sponsored by the Movement Disorder Society, the National Institute of Neurological Disorders and Stroke, and the National Institute of Mental Health.
He and his colleagues sent the 22-question, online survey to 2,104 members of the Movement Disorder Society and asked that those who did not have experience in managing or diagnosing PMDs not fill it out. Of 519 (25%) neurologists who responded, 43% practice in the United States, 32% in Europe or Canada, and 25% in other countries. Most of them practiced in an academic setting (55%).
In reaching a diagnosis, 74% of the respondents said they ask psychiatrists or other mental health professionals to assess a patient for underlying psychopathology before they discuss the diagnosis with the patient. A majority (52%) said they diagnose and attempt to secure expert management, 40% reported diagnosing and coordinating interdisciplinary long-term management, 5% said they diagnose and personally manage, and 3% diagnose only.
Nearly a quarter said they have no access to an electrophysiology laboratory, but most of those who do use them to confirm PMD only when clinical examination alone is insufficient. Many (40%) said they never or rarely use test results to explain the diagnosis to the patient and 21% said they often or always do so.
The clinical findings of incongruent movement, psychogenic signs, and inconsistency over time were each thought to be essential for a clinically definite diagnosis of PMD by more than half of the respondents and only 8% thought that an obvious psychiatric disturbance was essential for a clinically definite diagnosis.
Fifty-one percent of the respondents said that even when the patient shows clinically definite evidence of PMD, they request a battery of tests such as brain MRI, EEG, and carotid ultrasound, and then present the diagnosis.
In an interview, Dr. Espay called this the “most damning aspect of the survey,” because a PMD diagnosis can be established on clinical evidence alone. Even if such tests produce positive results, they will not explain the problem, because PMDs are not associated with any detectable physiologic or anatomic abnormalities. This approach suggests a many PMD experts “still treat psychogenic movement disorders as a diagnosis of exclusion.”
The respondents indicated that an excessive loss of function or disability relative to what was found in the clinical examination is the greatest predictor of a PMD diagnosis. U.S. respondents were more likely than their overseas counterparts to give a PMD diagnosis if a patient had spontaneous remissions and cures, associated nonphysiologic deficits, a history of mental health problems or psychological stressors, or ongoing litigation related to the patient's condition.
About two-thirds of the respondents reported that they refer PMD patients to a psychiatrist or a mental health specialist while also providing personal follow-up. But about half said mental health professionals at least sometimes question their original diagnosis and recommend that the neurologic basis for the disorder should be reconsidered.
Few respondents rated common treatment strategies such as avoiding iatrogenic harm, patient education, psychotherapy with or without drug therapy, rehabilitation services, and drug therapy for a specific movement impairment as “very” or “extremely” effective.
Slightly more than half of the respondents thought that the identification and management of a concurrent psychiatric disorder or psychological stressor are important predictors of prognosis. Another 60% thought that “acceptance of the diagnosis by the patient” is an extremely important predictor of prognosis.