Functional tremor and functional movement disorders are a daily clinical problem. They are common and difficult to diagnose. They become even more difficult to manage, as many people do not accept or understand the functional nature of their problem. It is as if they prefered to have some complex disease, impossible to treat. Many come with the idea that they suffer of Gilles de la Tourette syndrome, and appear frustrated when it becomes clear that their problem is not so exotic.
Zeuner and Sidiropoulos. Neurology 2019, 93:825-826
Espay et al. Neurology 2019, 93:e1787-e1798
Functional tremor and movement disorders may account for 5-15% of the clinical load in specialized movement disorder clinics, and patients appear regularly in general neurology clinics. The most common is functional tremor, and the second dystonia. The diagnosis is based on history, phenomenology and electrophysiology, including vídeo-electroencephalogram. There are very few publications on treatment. Physicians have great difficulty going further than comunicating the diagnosis to patients and their families, which does not help them very much. In fact this attitude might just drive patients to another neurologist along the line. Some publications mention rehabilitation, biofeedback and multiprofissional treatment.
In the study of Espay et al mentioned above patients had cingulate gyrus activation on fMRI when hey were symptomatic. This decreased along with the good response to cognitive behavior therapy. This marker of the disorder, in case it is replicated in other studies, will be a fascinating addition to this complex field. It follows the field of neurocognition in which many seats of mental processes are slowly receiving an anatomical correlation.
The treatment program used in this study of functional tremor involved a 12-week program of cognitive behavior therapy. The investigators concluded that the motor system is not involved in functional tremor. The problem is mental. 70% of 15 patients improved 100%, and the predictors of good prognosis were age below 50 years and recent onset.
Dr Paulo Bittencourt
