Neuropsychological and Neuropsychiatric Features of Idiopathic and DYT1 Dystonia and the Impact of Medical and Surgical treatment

Abstract

Dystonia is a hyperkinetic movement disorder, characterized by sustained or intermittent muscle contractions causing abnormal, often repetitive, movements, postures, or both. Executive dysfunction is a feature of cognitive function in idiopathic and DYT1 dystonia. Psychiatric morbidity is increased in dystonia, and depression, anxiety, obsessive compulsive disorders are the most common disorders. Sleep problems and pain are also frequently experienced. Evidence suggest that mood and anxiety disorders are intrinsic to the neurobiology of dystonia, but also that psychiatric co-morbidity can be secondary to pain experience and the psychosocial functioning and quality of life of the patients. Medical treatment of dystonia with botulinum toxin injections into affected muscles or with deep brain stimulation surgery improves the symptoms as well as mood and the quality of the patients and does not produce any adverse effects on cognitive function.

A Review of Cognitive Outcomes Across Movement Disorder Patients Undergoing Deep Brain Stimulation

“…Pathophysiology of cognitive modifications in dystonia after DBS is not concrete, but a few theories have been postulated to explain potential dysfunctions: anti-dystonic medications affecting memory (133, 134), concurrent mood disorders (i.e., depression or anxiety) leading to impairments in executive function or other cognitive domains (135–138), or severe motor impairments shadowing intact cognitive functioning (139, 140). Altogether, evidence suggests that dystonia patients have intact global cognition, language and memory, while isolated incidents of impaired executive function and sustained attention may stem from fronto-striatal abnormalities (137, 140, 141). The DBS studies reviewed do not recall potential cognitive circuits disrupted during DBS, but many conclude that changes post-DBS are congruent with a decrease in anti-cholinergic medication (14, 15), a lessening of burden from suppressing motor symptoms of dystonia (9, 13), already present executive dysfunction or impaired sustained attention (17), or practice effects of the task (9, 13).…”

Functional and cognitive capacity differ in dystonic motor subtypes when compared to choreatic and hypokinetic‐rigid motor subtypes in Huntington's disease

“…Besides, less executive function was observed in the hypokinetic versus the choreatic group (PBA score). This is remarkable because patients with focal dystonia complained about increased psychiatric symptoms with depression, anxiety, and obsessive‐compulsive disorders (Jahanshahi, 2017). We therefore initially hypothesize that dystonia may lead to more depression in HD which is however not supported by our data.…”

Postsynaptic movement disorders: clinical phenotypes, genotypes, and disease mechanisms

“…Patients manifest with isolated dystonia in childhood or adolescence, usually without any other associated neurological abnormalities (Ozelius and Lubarr 1993 ). Though not part of the initial presentation, executive dysfunction and psychiatric comorbidities such as mood and anxiety disorders have been described in DYT1 dystonia (Jahanshahi 2017 ). In the early course of disease, dystonia usually affects one (usually lower) limb and is often related to specific actions (action-induced or task-specific dystonia).…”