Life with chronic pain during COVID-19 lockdown: the case of patients with small fibre neuropathy and chronic migraine.

OBJECTIVE: We aimed at investigating the impact of COVID-19-related distress on patients with chronic pain, highlighting the effects of changes in individual habits and public health care reconfiguration on physical and psychological health. METHODS: During the pandemic, 80 participants (25 patients with small fibre neuropathy (SFN), 42 patients with chronic migraine (CM) and 13 patients' healthy family members (HFM)) were asked to evaluate their COVID-19 complains, changes in habits and clinical management, behaviour, mood, loneliness, quality of life (QoL), physical and mental health and coping strategies. Data were analysed by Spearman rho correlations and Mann-Whitney U tests. RESULTS: Patients had lower QoL, lower physical health and higher catastrophizing attitude towards pain than HFM. During the pandemic, SFN patients referred greater decline in clinical symptoms, worries about contagion and discomfort for disease management changes than CM patients. In the SFN group, the higher levels of disability were associated with suffering from changes in neurologist-patient relationship. CM patients complained of agitation/anxiety that was related to feelings of loneliness, depressive mood and catastrophism. DISCUSSION: Despite similar complains of change in habits and worries about COVID-19 pandemic, SFN and CM patients had distinct reactions. In SFN patients, pandemic distress impacted on physical health with worsening of clinical conditions, especially suffering from changes in their care. In CM patients, pandemic distress affected behaviour, mainly with psychological frailty. This suggests the need to customize public health care for patients with distinct chronic pain conditions.

Complex syndromes of chronic pain, fatigue and cognitive impairment linked to autoimmune dysautonomia and small fiber neuropathy.

Chronic fatigue syndrome, postural orthostatic tachycardia syndrome, complex regional pain syndrome and silicone implant incompatibility syndrome are a subject of debate among clinicians and researchers. Both the pathogenesis and treatment of these disorders require further study. In this paper we summarize the evidence regarding the role of autoimmunity in these four syndromes with respect to immunogenetics, autoimmune co-morbidities, alteration in immune cell subsets, production of autoantibodies and presentation in animal models. These syndromes could be incorporated in a new concept of autoimmune neurosensory dysautonomia with the common denominators of autoantibodies against G-protein coupled receptors and small fiber neuropathy. Sjogren's syndrome, which is a classical autoimmune disease, could serve as a disease model, illustrating the concept. Development of this concept aims to identify an apparently autoimmune subgroup of the disputable disorders, addressed in the review, which may most benefit from the immunotherapy.

Facts and myths pertaining to fibromyalgia.

Fibromyalgia (FM) is characterized by chronic widespread pain, unrefreshing sleep, physical exhaustion, and cognitive difficulties. It occurs in all populations throughout the world, with prevalence between 2% and 4% in general populations. Definition, pathogenesis, diagnosis, and treatment of FM remain points of contention, with some even contesting its existence. The various classification systems according to pain medicine, psychiatry, and neurology (pain disease; persistent somatoform pain disorder; masked depression; somatic symptom disorder; small fiber neuropathy; brain disease) mostly capture only some components of this complex and heterogeneous disorder. The diagnosis can be established in most cases by a general practitioner when the symptoms meet recognized criteria and a somatic disease sufficiently explaining the symptoms is excluded. Evidence-based interdisciplinary guidelines give a strong recommendation for aerobic exercise and cognitive behavioral therapies. Drug therapy is not mandatory. Only a minority of patients experience substantial symptom relief with duloxetine, milnacipran, and pregabalin.

La fibromialgia (FM) se caracteriza por dolor crónico generalizado, sueño no reparador, agotamiento físico y dificultades cognitivas. Ella se presenta en todas las poblaciones a través del mundo, con una prevalencia entre el 2% y el 4% en la población general. La definición, la patogénesis, el diagnóstico y el tratamiento de la FM constituyen puntos de discusión, con algunos autores que incluso dudan de su existencia. Los diversos sistemas de clasificación de acuerdo con la medicina, la psiquiatría y la neurología del dolor (patología dolorosa, trastorno de dolor somatomorfo persistente, depresión enmascarada, trastorno de síntoma somático, neuropatía de fibra pequeña, enfermedad cerebral) en su mayoría incorporan sólo algunos componentes de este complejo y heterogéneo trastorno. En la mayoría de los casos un médico general puede establecer el diagnóstico, cuando los síntomas reúnen criterios reconocidos y se excluye una enfermedad somática que pueda explicar suficientemente dichos síntomas. Las guías interdisciplinarias basadas en la evidencia entregan una sólida recomendación respecto al ejercicio aeróbico y las terapias cognitivo conductuales. La terapia farmacológica no es obligatoria. Sólo una minoría de los pacientes presenta un alivio sintomático significativo con duloxetina, milnacipran y pregabalina.

La fibromyalgie (FM) se caractérise par des douleurs chroniques généralisées, un sommeil non réparateur, un épuisement physique et des difficultés cognitives. Elle survient dans toutes les populations du monde, avec une prévalence entre 2 % et 4 % de la population générale. La définition, la pathogenèse, le diagnostic et le traitement de la FM restent un point de discorde, quelques-uns contestant même son existence. Les systèmes de classification variés selon la médecine, la psychiatrie et la neurologie de la douleur, (pathologie douloureuse ; trouble douloureux somatoforme persistant ; dépression masquée ; trouble à symptomatologie somatique ; neuropathie des petites fibres ; maladie cérébrale) n'appréhendent principalement que quelques composantes de ce trouble complexe et hétérogène. Le diagnostic peut être établi dans la plupart des cas par un généraliste quand les symptômes rencontrés remplissent les critères et quand une maladie somatique capable d'expliquer les symptômes est exclue. Des recommandations interdisciplinaires fondées sur des éléments probants recommandent fortement les exercices aérobiques et les thérapies cognitivo-comportementales. Le traitement médicamenteux n'est pas obligatoire. Seule une minorité de patients sont soulagés par la duloxétine, le milnacipran et la prégabaline.

Impact of pain on cognitive functions in primary Sjögren syndrome with small fiber neuropathy: 10 cases and a literature review.

Primary Sjögren syndrome (pSS) is a chronic systemic autoimmune disease characterized by xerophthalmia, xerostomia, and potential peripheral or central neurological involvement. In pSS, the prevalence of cognitive disorders is generally sparse across literature and the impact of pain on cognitive profile is unclear. The aim of this study was to determine the relation between pain, cognitive complaint, and impairment in a very homogenous population of 10 pSS patients with painful small fiber neuropathy (PSFN) and spontaneous cognitive complaint. Neurological exam, neuropsychological assessment, clinical evaluation measuring pain level, fatigue, anxiety, depression, and cognitive complaint were performed. Our results showed that 100% of patients had cognitive dysfunction especially in executive domain (80%). The most sensitive test was the Wisconsin Card Sorting Test (WCST), abnormal in 70% of our population. Moreover, we found clear cut significant correlations between pain levels and 3 measures of WCST: the number of errors (R = -0.768, P = .0062), perseverations (R = 0.831, P = .0042), and categories (R = 0.705, P = .02). In the literature review, the impact of pain is underexplored and results could be discordant. In a homogeneous cohort of pSS patients with PSFN, a cognitive complaint seems to be a valid reflection of cognitive dysfunction marked by a specific executive profile found with the WCST. In this preliminary study, this profile is linked to the level of pain and highlights that an appropriate management of pain control and a cognitive readaptation in patients could improve the quality of life.

Initial Development and Validation of a Patient-Reported Symptom Survey for Small-Fiber Polyneuropathy.

Small-fiber polyneuropathy (SFPN) affects unmyelinated and thinly myelinated peripheral axons. Several questionnaires have been developed to assess polyneuropathy from diabetes or chemotherapy, but none for SFPN from other or unknown causes. A comprehensive survey could help clinicians diagnose and assess treatment responses, define prevalence natural history and cures, and identify research subjects. Thus, we developed the 1-page Small-Fiber Symptom Survey, using input from patients and 21 medical/scientific experts. Participants comprised consenting consecutive patients evaluated for SFPN at the Massachusetts General Hospital plus normal control subjects. Participants SFPN status was stratified on the basis of the results of their objective diagnostic tests (distal leg skin biopsy and autonomic function testing). We measured internal consistency, test retest reliability, convergent validity, and performed a receiver operating curve analysis. The 179 participants averaged 46.6 ± 15.6 years old; they were 73.2% female and 92.2% Caucasian. Eighty-five had confirmed SFPN, mostly idiopathic. Principal component analysis revealed 5 symptom clusters. The questionnaire had good internal consistency (Cronbach α = .893), excellent test retest reliability (r = .927, P < .001) and good to fair convergent validity. Participants with confirmed SFPN had more severe symptoms than others (P = .009). The Small-Fiber Symptom Survey has satisfactory psychometric properties, indicating potential future utility for surveying patient-reported symptoms of SFPN regardless of its cause. PERSPECTIVE: This article reports the initial development and early psychometric validation of a new patient-reported outcome measure intended to capture the wide range of multisystem symptoms of SFPN. When further developed, it could potentially help clinicians diagnose and monitor patients, and help advance research.