Briquet syndrome revisited: implications for functional neurological disorder

Abstract

With the creation of the Somatic Symptom and Related Disorders category of the Diagnostic and Statistical Manual of Mental Disorders–Fifth Edition (DSM-5) in 2013, the functional neurological (symptom) disorder diagnostic criteria underwent transformative changes. These included an emphasis on “rule-in” physical examination signs/semiological features guiding diagnosis and the removal of a required proximal psychological stressor to be linked to symptoms. Additionally, the DSM–Fourth Edition (DSM-IV) somatization disorder, somatoform pain disorder and undifferentiated somatoform disorder conditions were eliminated and collapsed into the DSM-5 somatic symptom disorder diagnosis. With somatic symptom disorder, emphasis was placed on a cognitive-behavioral (psychological) formulation as the basis for diagnosis in individuals reporting distressing bodily symptoms such as pain and fatigue; the need for bodily symptoms to be “medically unexplained” was removed, and the overall utility of this diagnostic criteria remains debated. A consequence of the DSM-5 restructuring is that the diagnosis of somatization disorder that encompassed individuals with functional neurological (sensorimotor) symptoms and prominent other bodily symptoms, including pain, was eliminated. This change negatively impacts clinical and research efforts because many patients with functional neurological disorder experience pain, supporting that the DSM-5 would benefit from an integrated diagnosis at this intersection. We seek to revisit this with modifications, particularly since pain (and a DSM-IV somatization disorder comorbidity, more specifically) is associated with poor clinical prognosis in functional neurological disorder. As a first step, we systematically reviewed the DSM-IV somatization disorder literature to detail epidemiologic, healthcare utilization, demographic, diagnostic, medical and psychiatric comorbidity, psychosocial, neurobiological and treatment data. Thereafter, we propose a preliminary revision to DSM-5 allowing for the specifier functional neurological disorder “with prominent pain”. To meet this criteria, core functional neurological symptoms (e.g., limb weakness, gait difficulties, seizures, non-dermatomal sensory loss, and/or blindness) would have “rule-in” signs and pain (> 6 months) impairing social and/or occupational functioning would also be present. Two optional secondary specifiers assist in characterizing individuals with cognitive-behavioral (psychological) features recognized to amplify or perpetuate pain and documenting if there is a pain-related comorbidity. The specifier of “with prominent pain” is etiologically neutral, while secondary specifiers provide additional clarification. We advocate for a similar approach to contextualize fatigue and mixed somatic symptoms in functional neurological disorder. While this preliminary proposal requires prospective data and additional discussion, these revisions offer the potential benefit to readily identify important functional neurological disorder subgroups - resulting in diagnostic, treatment and pathophysiology implications.

Neuroimaging in Functional Neurological Disorder: State of the Field and Research Agenda

“…Note, this neuroimaging-focused research agenda is partially informed by recently published pathophysiology-focused research agenda formulations ( Drane et al, 2020 , Pick et al, 2019 ). FND cohorts in neuroimaging studies require more detailed categorical and dimensional characterization across neurological, medical and psychiatric/psychological domains: while emphasis on positive signs should remain a key inclusion criterion, future research should make concerted efforts to describe and quantify the range of functional neurological symptoms and other bodily symptoms experienced by individuals - most notably but not limited to pain, fatigue, and cognitive complaints ( Maggio et al, 2020 , Nicholson et al, 2020 ). Additional work is also needed to operationalize and further validate rule-in signs for FND.…”

Diagnosis and management of functional neurological disorder

“…Nonetheless, unanswered questions remain, including optimal and cost effective treatment settings (eg, inpatient versus day hospital versus outpatient versus tele-physiotherapy) as well as the optimal frequency and intensity 19202203. More research is needed regarding the management of commonly present non-motor symptoms, such as pain and fatigue 204. A large scale RCT for physiotherapy for motor FND currently under way will likely help clarify some of these questions 205…”

Соматоформное Расстройство: Исторический Аспект И Актуальное Состояние Проблемы В Современных Условиях (Литературный Обзор)

“…Так, в клинических интерпретациях северо-американских систематик психических и поведенческих расстройств (DSM-3R, DSM-4TR) в качестве механизмов формирования СФР, помимо «соматизации», не исключаются и механизмы «соматической конверсии», которые рассматриваются отдельно и независимо от диссоциативных расстройств. В целом вся группа соматоформных расстройств до настоящего времени в северноамериканских источниках интерпретируется по происхождению как синдром Брике, первоначально имеющий отношение к описаниям истерических стигматов [55,58]. Если учитывать то обстоятельство, что «мягкая соматизация», характеризующаяся двумя или тремя симптомами необъективизируемых соматических нарушений, постоянно беспокоящих пациента более 2 лет, встречающаяся в первичном звене медицинской помощи более чем в 8,2% наблюдений, то становится вполне объяснимой некорректность общемировой статистики, касающейся соматоформного расстройства [54].…”