Clinical Correlates of Functional Motor Disorders: An Italian Multicenter Study

Abstract

Background Background: Functional motor disorders (FMDs) are abnormal movements that are significantly altered by distractive maneuvers and are incongruent with movement disorders seen in typical neurological diseases. Objective Objective: The objectives of this article are to (1) describe the clinical manifestations of FMDs, including nonmotor symptoms and occurrence of other functional neurological disorders (FND); and (2) to report the frequency of isolated and combined FMDs and their relationship with demographic and clinical variables. Methods Methods: For this multicenter, observational study, we enrolled consecutive outpatients with a definite diagnosis of FMDs attending 25 tertiary movement disorders centers in Italy. Each patient underwent a detailed clinical evaluation with a definition of the phenotype and number of FMDs (isolated, combined) and an assessment of associated neurological and psychiatric symptoms. Results Results: Of 410 FMDs (71% females; mean age, 47 AE 16.1 years) the most common phenotypes were weakness and tremor. People with FMDs had higher educational levels than the general population and frequent nonmotor symptoms, especially anxiety, fatigue, and pain. Almost half of the patients with FMDs had other FNDs, such as sensory symptoms, nonepileptic seizures, and visual symptoms. Patients with combined FMDs showed a higher burden of nonmotor symptoms and more frequent FNDs. Multivariate regression analysis showed that a diagnosis of combined FMDs was more likely to be delivered by a movement disorders

Demographic and clinical characteristics of patients with functional motor disorders: the prospective Salpêtrière cohort

“…The majority of patients were women with a median age at the symptoms onset of 35 years old, with a wide age range. These demographic characteristics are similar to those of previous smaller cohorts of adults suffering from FMDs, which reported a proportion of women between 48 and 84% and a mean age at onset between 29.7 and 46.9 years old (Factor, Podskalny, et Molho 1995; Binzer, Andersen, et Kullgren 1997; Schrag et al 2004; Jon Stone, Warlow, et Sharpe 2010; Pandey et Koul 2017; Baizabal-Carvallo et Jankovic 2020; Tinazzi et al 2020; Anderson et al 2007; Gelauff et al 2020)(see table 4). It should be noted that extreme ages were under-represented, since wee did not include children, and older patients may be under diagnosed.…”

“…Amongst movement disorders, tremor and dystonia were the most prevalent presentations, this has also been described in previous cohorts of movement disorders (Factor, Podskalny, et Molho 1995; Pandey et Koul 2017; Baizabal-Carvallo et Jankovic 2020; Tinazzi et al 2020; Anderson et al 2007)…”

“…An acute or subacute onset was reported in 95 % of patients in our cohort. Acute onset is often reported in FMD, and was noticed in the majority of patients in previous cohorts of FMD (Jon Stone, Warlow, et Sharpe 2012; Tinazzi et al 2020; Factor, Podskalny, et Molho 1995; Pandey et Koul 2017). It is usually considered as a clue for the diagnosis of functional movement disorders (Espay et al 2018).…”

“…Patients present with a variety of symptoms of altered movement, including weakness, tremor, jerks, stereotypies, dystonia and parkinsonism, often displaying combinations of multiple phenotypes. FMD is known to predominantly affect women and to start at young to middle age (Baizabal-Carvallo et Jankovic 2020; Tinazzi et al 2020; Binzer, Andersen, et Kullgren 1997; Schrag et al 2004; Factor, Podskalny, et Molho 1995; Jon Stone, Warlow, et Sharpe 2010). Recent studies have suggested that some phenotypes affect more one gender or one age range.…”

Functional motor disorders associated with other neurological diseases: Beyond the boundaries of “organic” neurology

“…For this cross‐sectional study, data were extracted from the Italian Registry of Functional Motor Disorders (IRFMD), managed by the Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, and by the Italian Academy for the Study of Parkinson's Disease and Other Movement Disorders (Accademia LIMPE‐DISMOV). Full methods of the IRFMD are explained elsewhere [12].…”