A systematic review of quantitative EEG findings in Fibromyalgia, Chronic Fatigue Syndrome and Long COVID.

Fibromyalgia Syndrome (FMS), Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Long COVID (LC) are similar multisymptom clinical syndromes but with difference in dominant symptoms in each individual. There is existing and emerging literature on possible functional alterations of the central nervous system in these conditions. This review aims to synthesise and appraise the literature on resting-state quantitative EEG (qEEG) in FMS, ME/CFS and LC, drawing on previous research on FMS and ME/CFS to help understand neuropathophysiology of the new condition LC. A systematic search of MEDLINE, Embase, CINHAL, PsycINFO and Web of Science databases for articles published between December 1994 and September 2023 was performed. Out of the initial 2510 studies identified, 17 articles were retrieved that met all the predetermined selection criteria, particularly of assessing qEEG changes in one of the three conditions compared to healthy controls. All studies scored moderate to high quality on the Newcastle-Ottawa scale. There was a general trend for decreased low-frequency EEG band activity (delta, theta, and alpha) and increased high-frequency EEG beta activity in FMS, differing to that found in ME/CFS. The limited LC studies included in this review focused mainly on cognitive impairments and showed mixed findings not consistent with patterns observed in FMS and ME/CFS. Our findings suggest different patterns of qEEG brainwave activity in FMS and ME/CFS. Further research is required to explore whether there are phenotypes within LC that have EEG signatures similar to FMS or ME/CFS. This could inform identification of reliable diagnostic markers and possible targets for neuromodulation therapies tailored to each clinical syndrome.

What are the experiences of people with motor and sensory functional neurological disorder? A systematic review and thematic synthesis of qualitative studies.

PURPOSE: Functional neurological disorders are common, highly stigmatised and associated with significant disability. This review aimed to synthesise qualitative research exploring the experiences of people living with motor and/or sensory FND. Identifying their needs should inform service development, education for healthcare professionals and generate future research questions. METHOD: Five databases were systematically searched (Medline, PsychInfo, Web of Science, Embase and Cinahl) in November 2022, updated in June 2023. Data from included papers was extracted by two authors and studies were critically appraised using the Critical Appraisal Skills Programme (CASP). Data was thematically analysed and synthesised. RESULTS AND CONCLUSIONS: 12 papers were included in the synthesis describing the views of 156 people with FND. The overarching theme was uncertainty; about what caused FND and how to live with it. Uncertainty was underpinned by four analytic themes; challenging healthcare interactions, loss of power and control, who or what is responsible and living with a visible disability and an invisible illness. Early and clear diagnosis, validation and support for living with FND should form part of multidisciplinary care. Co-produced service development, research agendas and education for clinicians, patients and the public would reduce stigma and improve the experiences of people with FND.

A clear diagnosis and explanation of motor and/or sensory functional neurological disorder is validating and an important first step in recovery.People with motor and/or sensory functional neurological disorder experience significant disability, stigma, self-blame and functional impairment.Multidisciplinary care pathways for functional neurological disorder urgently need to be developed.There is a need for co-produced education and training for healthcare professionals which covers how to deliver diagnoses and personalised formulations, communicate concepts of applied neuroscience and challenges stigma and discrimination.