Functional motor disorders associated with other neurological diseases: Beyond the boundaries of “organic” neurology
Corresponding Author
Michele Tinazzi
Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
Correspondence
Michele Tinazzi and Christian Geroin, Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy. P.le Scuro 10, 37134, Verona, Italy.
Email: [email protected] (MT); [email protected] (CG)
Contribution: Conceptualization (lead), Data curation (lead), Formal analysis (lead), Investigation (lead), Methodology (lead), Writing - original draft (lead), Writing - review & editing (lead)
Search for more papers by this authorCorresponding Author
Christian Geroin
Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
Correspondence
Michele Tinazzi and Christian Geroin, Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy. P.le Scuro 10, 37134, Verona, Italy.
Email: [email protected] (MT); [email protected] (CG)
Contribution: Conceptualization (lead), Data curation (lead), Formal analysis (lead), Investigation (lead), Methodology (lead), Writing - original draft (lead), Writing - review & editing (lead)
Search for more papers by this authorRoberto Erro
Department of Medicine, Surgery and Dentistry -Scuola Medica Salernitana, Center for Neurodegenerative Diseases (CEMAND), University of Salerno, Baronissi, SA, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorEnrico Marcuzzo
Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorSofia Cuoco
Department of Medicine, Surgery and Dentistry -Scuola Medica Salernitana, Center for Neurodegenerative Diseases (CEMAND), University of Salerno, Baronissi, SA, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorRoberto Ceravolo
Neurology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorSonia Mazzucchi
Neurology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAndrea Pilotto
Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
FERB Onlus, Ospedale S. Isidoro, Trescore Balneario, Bergamo, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAlessandro Padovani
Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorLuigi Michele Romito
Parkinson and Movement Disorders Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
Search for more papers by this authorRoberto Eleopra
Parkinson and Movement Disorders Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorMario Zappia
Section of Neurosciences, Department G.F. Ingrassia, University of Catania, Catania, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAlessandra Nicoletti
Section of Neurosciences, Department G.F. Ingrassia, University of Catania, Catania, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorCarlo Dallocchio
Neurology Unit, Department of Medical Area, ASST Pavia, Pavia, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorCarla Arbasino
Neurology Unit, Department of Medical Area, ASST Pavia, Pavia, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorFrancesco Bono
Botulinum Toxin Center, Neurology Unit, A.O.U. Mater Domini, Catanzaro, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAngelo Pascarella
Botulinum Toxin Center, Neurology Unit, A.O.U. Mater Domini, Catanzaro, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorBenedetta Demartini
Aldo Ravelli Research Center for Neurotechnology and Experimental Brain Therapeutics - Department of Health Sciences, University of Milan, Milan, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorOrsola Gambini
Aldo Ravelli Research Center for Neurotechnology and Experimental Brain Therapeutics - Department of Health Sciences, University of Milan, Milan, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorNicola Modugno
IRCCS Neuromed, Pozzilli, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorEnrica Olivola
IRCCS Neuromed, Pozzilli, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorLaura Bonanni
Department of Neuroscience, Imaging and Clinical Sciences, University G. d'Annunzio, Chieti-Pescara, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorElena Antelmi
Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorElisabetta Zanolin
Unit of Epidemiology and Medical Statistics, Department of Diagnostics and Public Health, University of Verona, Verona, Italy
Contribution: Data curation (supporting), Formal analysis (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAlberto Albanese
Department of Neurology, IRCCS Humanitas Research Hospital, Milan, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorGina Ferrazzano
Department of Human Neurosciences, Università La Sapienza, Rome, Italy
Search for more papers by this authorRosa de Micco
Department of Advanced Medical and Surgery Sciences, University of Campania - Luigi Vanvitelli, Naples, Italy
Search for more papers by this authorLeonardo Lopiano
Department of Neuroscience - Rita Levi Montalcini, University of Turin, Turin, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorGiovanna Calandra-Buonaura
Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
Institute of Neurological Sciences of Bologna, IRCCS, Bologna, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorMartina Petracca
Movement Disorder Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorMarcello Esposito
Clinical Neurophysiology Unit, Cardarelli Hospital, Naples, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAntonio Pisani
IRCCS Mondino Foundation, Pavia, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorPaolo Manganotti
Clinical Neurology Unit, Department of Medical, Surgical and Health Services, University of Trieste, Trieste, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorFabrizio Stocchi
University and Institute of Research and Medical Care San Raffaele, Roma, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorMario Coletti Moja
Mauriziano Hospital Umberto I, Turin, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAngelo Antonini
Movement Disorders Unit, Department of Neuroscience, University of Padua, Padua, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorTommaso Ercoli
Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorFrancesca Morgante
Neurosciences Research Centre, Molecular and Clinical Sciences Neurosciences Research Centre, Molecular and Clinical Sciences Research Institute, St George's University of London, London, UK
Department of Experimental and Clinical Medicine, University of Messina, Messina, Italy
Contribution: Conceptualization (lead), Formal analysis (lead), Methodology (lead), Writing - original draft (lead), Writing - review & editing (lead)
Search for more papers by this authorCorresponding Author
Michele Tinazzi
Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
Correspondence
Michele Tinazzi and Christian Geroin, Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy. P.le Scuro 10, 37134, Verona, Italy.
Email: [email protected] (MT); [email protected] (CG)
Contribution: Conceptualization (lead), Data curation (lead), Formal analysis (lead), Investigation (lead), Methodology (lead), Writing - original draft (lead), Writing - review & editing (lead)
Search for more papers by this authorCorresponding Author
Christian Geroin
Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
Correspondence
Michele Tinazzi and Christian Geroin, Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy. P.le Scuro 10, 37134, Verona, Italy.
Email: [email protected] (MT); [email protected] (CG)
Contribution: Conceptualization (lead), Data curation (lead), Formal analysis (lead), Investigation (lead), Methodology (lead), Writing - original draft (lead), Writing - review & editing (lead)
Search for more papers by this authorRoberto Erro
Department of Medicine, Surgery and Dentistry -Scuola Medica Salernitana, Center for Neurodegenerative Diseases (CEMAND), University of Salerno, Baronissi, SA, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorEnrico Marcuzzo
Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorSofia Cuoco
Department of Medicine, Surgery and Dentistry -Scuola Medica Salernitana, Center for Neurodegenerative Diseases (CEMAND), University of Salerno, Baronissi, SA, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorRoberto Ceravolo
Neurology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorSonia Mazzucchi
Neurology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAndrea Pilotto
Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
FERB Onlus, Ospedale S. Isidoro, Trescore Balneario, Bergamo, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAlessandro Padovani
Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorLuigi Michele Romito
Parkinson and Movement Disorders Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
Search for more papers by this authorRoberto Eleopra
Parkinson and Movement Disorders Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorMario Zappia
Section of Neurosciences, Department G.F. Ingrassia, University of Catania, Catania, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAlessandra Nicoletti
Section of Neurosciences, Department G.F. Ingrassia, University of Catania, Catania, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorCarlo Dallocchio
Neurology Unit, Department of Medical Area, ASST Pavia, Pavia, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorCarla Arbasino
Neurology Unit, Department of Medical Area, ASST Pavia, Pavia, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorFrancesco Bono
Botulinum Toxin Center, Neurology Unit, A.O.U. Mater Domini, Catanzaro, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAngelo Pascarella
Botulinum Toxin Center, Neurology Unit, A.O.U. Mater Domini, Catanzaro, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorBenedetta Demartini
Aldo Ravelli Research Center for Neurotechnology and Experimental Brain Therapeutics - Department of Health Sciences, University of Milan, Milan, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorOrsola Gambini
Aldo Ravelli Research Center for Neurotechnology and Experimental Brain Therapeutics - Department of Health Sciences, University of Milan, Milan, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorNicola Modugno
IRCCS Neuromed, Pozzilli, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorEnrica Olivola
IRCCS Neuromed, Pozzilli, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorLaura Bonanni
Department of Neuroscience, Imaging and Clinical Sciences, University G. d'Annunzio, Chieti-Pescara, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorElena Antelmi
Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorElisabetta Zanolin
Unit of Epidemiology and Medical Statistics, Department of Diagnostics and Public Health, University of Verona, Verona, Italy
Contribution: Data curation (supporting), Formal analysis (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAlberto Albanese
Department of Neurology, IRCCS Humanitas Research Hospital, Milan, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorGina Ferrazzano
Department of Human Neurosciences, Università La Sapienza, Rome, Italy
Search for more papers by this authorRosa de Micco
Department of Advanced Medical and Surgery Sciences, University of Campania - Luigi Vanvitelli, Naples, Italy
Search for more papers by this authorLeonardo Lopiano
Department of Neuroscience - Rita Levi Montalcini, University of Turin, Turin, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorGiovanna Calandra-Buonaura
Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
Institute of Neurological Sciences of Bologna, IRCCS, Bologna, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorMartina Petracca
Movement Disorder Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorMarcello Esposito
Clinical Neurophysiology Unit, Cardarelli Hospital, Naples, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAntonio Pisani
IRCCS Mondino Foundation, Pavia, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorPaolo Manganotti
Clinical Neurology Unit, Department of Medical, Surgical and Health Services, University of Trieste, Trieste, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorFabrizio Stocchi
University and Institute of Research and Medical Care San Raffaele, Roma, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorMario Coletti Moja
Mauriziano Hospital Umberto I, Turin, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorAngelo Antonini
Movement Disorders Unit, Department of Neuroscience, University of Padua, Padua, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorTommaso Ercoli
Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
Contribution: Data curation (supporting), Writing - review & editing (supporting)
Search for more papers by this authorFrancesca Morgante
Neurosciences Research Centre, Molecular and Clinical Sciences Neurosciences Research Centre, Molecular and Clinical Sciences Research Institute, St George's University of London, London, UK
Department of Experimental and Clinical Medicine, University of Messina, Messina, Italy
Contribution: Conceptualization (lead), Formal analysis (lead), Methodology (lead), Writing - original draft (lead), Writing - review & editing (lead)
Search for more papers by this authorAbstract
Background and purpose
The aims of this study were to describe the clinical manifestations of functional motor disorders (FMDs) coexisting with other neurological diseases (“comorbid FMDs”), and to compare comorbid FMDs with FMDs not overlapping with other neurological diseases (“pure FMDs”).
Methods
For this multicenter observational study, we enrolled outpatients with a definite FMD diagnosis attending 25 tertiary movement disorder centers in Italy. Each patient with FMDs underwent a detailed clinical assessment including screening for other associated neurological conditions. Group comparisons (comorbid FMDs vs. pure FMDs) were performed in order to compare demographic and clinical variables. Logistic regression models were created to estimate the adjusted odds ratios (95% confidence intervals) of comorbid FMDs (dependent variable) in relation to sociodemographic and clinical characteristics (independent variables).
Results
Out of 410 FMDs, 21.7% of patients (n = 89) had comorbid FMDs. The most frequent coexisting neurological diseases were migraine, cerebrovascular disease and parkinsonism. In the majority of cases (86.5%), FMDs appeared after the diagnosis of a neurological disease. Patients with comorbid FMDs were older, and more frequently had tremor, non-neurological comorbidities, paroxysmal non-epileptic seizures, major depressive disorders, and benzodiazepine intake. Multivariate regression analysis showed that diagnosis of comorbid FMDs was more likely associated with longer time lag until the final diagnosis of FMD, presence of tremor and non-neurological comorbidities.
Conclusions
Our findings highlight the need for prompt diagnosis of FMDs, given the relatively high frequency of associated neurological and non-neurological diseases.
CONFLICT OF INTERESTS
The authors declare no financial or other conflict of interest related to the content of this research. This study did not receive any industry funding. Financial disclosures for the previous 12 months are as follows. Francesca Morgante reports: speaking honoraria from Abbvie, Medtronic, Zambon, Bial, Merz; travel grants from the International Parkinson's Disease and Movement Disorder Society; advisory board fees from Merz, Bial, Abbvie; consultancy fees from Boston Scientific; research support from Boston Scientific, Merz and Global Kynetic; royalties for the book “Disorders of Movement” from Springer; and is a member of the editorial board of Movement Disorders, Movement Disorders Clinical Practice, European Journal of Neurology. Roberto Erro reports receiving honoraria from UCB, Bial, the International Society for Parkinson's Disease and Movement Disorders and the American Academy of Neurology. Roberto Ceravolo reports receiving speaking fees from Abbvie, Zambon, Lusofarmaco, UCB, and General Electric. Andrea Pilotto has served on the advisory board of Z-cube (Technology Division of Zambon Pharmaceuticals), and has received honoraria from Z-cube s.r.l., Biomarin, Zambon, Nutricia, and Chiesi Pharmaceuticals, grant funding from the Ministry of Health and H2020 calls, and independent research support from Vitaflo Germany and Zambon Italy. Alessandro Padovani is a consultant for and has served on the scientific advisory board of GE Healthcare, Eli Lilly, and Actelion Ltd Pharmaceuticals, and has received speaker fees from Nutricia, PIAM (PIAM Pharma & Integrative Care), Lansgstone Technology, GE Healthcare, Eli Lilly, UCB Pharma and Chiesi Pharmaceuticals, grants from the Ministry of the University, H2020, JPND (EU Joint Programme-Neurodegenerative Disease Research), CARIPLO restricted grants, and independent research support from Zambon, Italy. Maurizio Zibetti reports receiving speaker fees and grants from Medtronic, Zambon Pharma, UCB Pharma, and AbbVie. Fabrizio Stocchi reports receiving research/grant support from Zambon, and honoraria/consulting fees/compensation for advisory boards from Bial, Chiesi, Neuroderm, Britannia, Sunovion Pharmaceuticals Inc., Lundbeck, Zambon, Cynapsus, Biogen, and Kyowa. All other authors have no disclosures to report.
Open Research
DATA AVAILABILITY STATEMENT
Data for this study are available from the corresponding authors upon reasonable request.
Supporting Information
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