Non-motor symptoms in dystonia: from diagnosis to treatment

The Dystonia Medical Research Foundation organized an expert virtual workshop in March 2023 to review the evidence on non-motor symptoms across the spectrum of dystonia, discuss existing assessment methods, need for their harmonisation and roadmap to achieve this, and evaluate potential treatment approaches. Albeit the most investigated non-motor domains, experts highlighted the need to identify the most accurate screening procedure for depression and anxiety, clarify their mechanistic origin and quantify their response to already available therapies. Future exploration of sleep disruption in dystonia should include determining the accuracy and feasibility of wearable devices, understanding the contribution of psychotropic medication to its occurrence, and defining the interaction between maladaptive plasticity and abnormal sleep patterns. Despite recent advances in the assessment of pain in dystonia, more research is needed to elucidate the relative importance of different mechanisms called into play to explain this impactful sensory feature and the most appropriate treatments. Amongst the different non-motor features investigated in dystonia, cognitive dysfunction and fatigue require an in-depth observation to evaluate their functional impact, their clinical profile and assessment methods and, in the case of cognition, whether impairment represents a prodrome of dementia. Finally, experts identified the development and field validation of a self-rated screening tool encompassing the full spectrum of non-motor symptoms as the most urgent step towards incorporating the management of these features into routine clinical practice.