Acceptability and Feasibility of an Online Yoga Programme for Adults With a Functional Neurological Disorder.

1. BACKGROUND Functional neurological disorders (FND), previously named as either conversion disorder or somatic symptom disorder, are clinical conditions characterized by involuntary motor and sensory symptoms, for example seizures, paralysis, or a tremor, in the absence of any abnormal pathophysiology. Patients' memory, concentration, and cognition can also be impaired .The two most frequent presenting symptoms are seizure-like episodes, also known as dissociative or psychogenic non-epileptic seizures, or persistent motor effects that resemble a stroke. The current UK prevalence of FND is poorly understood with estimates ranging between 50,000 to 100,000, and an annual new incidence of 8,000. This is likely to be grossly underestimated, as FND is frequently misdiagnosed and thought to be the cause of up to 30% (n=1,444/4,299) of all presentations to neurology clinics and 10-20% of Neurology inpatients at Nottingham University Hospitals. FND is more common in women than men (3:1) and less common in infants than adults . In Nottinghamshire, approximately 100 people with FND seek advice from the neurology services at Nottingham University Hospitals NHS Trust each month either through clinics, telephone, or email. There is a significantly high burden of disability in this patient population, with physical symptoms equivalent to multiple sclerosis or epilepsy, along with anxiety, depression, chronic fatigue and "brain fog". The causes of FND remain unknown. It is difficult to diagnose FND because it cannot be explained as a medical or neurological disease, there is no formal gold standard diagnostic criteria, and there are currently no medical or physiotherapy curative treatments. Overall, the optimal healthcare management of people with FND remains a major challenge.

The absence of a definitive medical or physiotherapy cure for FND has led to the exploration by the Nottingham University Hospitals clinical team of non-medical approaches to symptom management. Yoga, a holistic physical, mental, and spiritual practice that originates from India, uses repetitive physical postures and stretches (asanas), breathing exercises (pranayama), and meditation (dyana) to improve physical and psychological wellbeing. Yoga has been demonstrated to improve the health related quality of life (HRQOL) in populations aged 60 years and over, and amongst adults with multiple sclerosis and reduce anxiety and depression. Overall, holistic approaches to care view the person as a whole being and consider their social, psychological, and spiritual needs in addition to their physical health needs.

In December 2023, a systematic search for publications detailing Yoga interventions for people with FND was conducted by the study Chief Investigator. This comprehensive search yielded two conference abstracts detailing the outcomes of case studies (n=3 patients) by the same author reporting improvements in pain, muscle spasms, balance, and anxiety. Thus, there are two research gaps present, namely knowledge (where research findings do not exist) and population (a lack of data pertaining to the population and phenomenon of interest). 2. RATIONALE The World Health Organization define health as being "a state of complete physical, mental and social well-being and not merely the absence of disease and infirmity". People living with FND experience symptoms in all three physical, mental and social well-being domains, accompanied by misunderstanding and stigmatizing behaviour by both members of the public and by healthcare professionals. Although the prevalence of FND is greater than that of multiple sclerosis and has similar symptom severity, both clinical treatment and clinical research opportunities are limited. Recommendations for the construction of an optimum clinical pathway for FND that recognises symptom heterogeneity and the need to integrate physical and psychological health services have been developed by the National Neurosciences Advisory Group. This clinical pathway includes the provision of practical self-management actions for patients. Yoga is a practical activity that can be taught and practiced individually in isolation or in facilitated groups.

In this study, the specific sub-population of people with FND of interest is those who experience psychogenic non-epileptic seizures (PNES), also known as dissociative seizures (DS). Seizures can be differentiated between being epileptic or non-epileptic by recording a seizure on video electroencephalography, or by an expert neurological clinical assessment of the history preceding a seizure, the characteristics of the seizure, and normal electroencephalography patterns during seizures and at baseline.

The association between PNES, and symptoms of depression and anxiety is established. The word yoga means unite, referring to the joining of the mind and body, so is an appropriate interventional approach to consider for this population. An integrative cognitive model of PNES posits that the seizures are linked to sympathetic nervous system activation by chronic stress or factors that compromise inhibitory control processing (a cognitive process that enables individuals to suppress impulses or strong behavioural responses to a stimuli). The Polyvagal Theory explains that feeling psychologically unsafe, even in situations that are objectively safe, unconsciously activates the sympathetic nervous system function, so it follows that this could be a further contributory factor.