Background: Myoclonus-dystonia (M-D) is a movement disorder frequently caused by mutations in the epsilon-sarcoglycan gene (SGCE, DYT11). In several M-D families, psychiatric symptoms accompanying the motor symptoms have been reported, but a shared genetic etiology remains unclear.
Objective: To assess neuropsychologic functioning and psychopathology in DYT11 mutation carriers (MC) and their family members using standardized neuropsychologic and psychiatric measures.
Methods: Cognitive and behavioural characteristics of 27 DYT11 MC (14 symptomatic and 13 asymptomatic) and 42 control subjects from 1 large Dutch M-D family were studied. Neuropsychologic tests encompassed memory, language, mental speed, concentration, visuospatial function, and executive functions. Psychiatric assessment addressed qualitative (according to Diagnostic and Statistical Manual-IV criteria) as well as quantitative measures of depression, anxiety, panic attacks, and obsessive-compulsive disorder (OCD), using selfadministered and interview-based scales.
Results: No differences were observed on tests of cognitive functioning between DYT11 MC and controls. The frequency of Diagnostic and Statistical Manual-IV diagnoses was higher in the symptomatic DYT11 MC than in controls. The symptomatic DYT11 MC showed more depressive and anxiety symptoms, including panic attacks but no increase of OCD compared with controls. No differences were found between asymptomatic DYT11 MC and controls on any of the psychopathologic tests.
Conclusions: Neither cognitive dysfunction nor OCD seems to be associated with the DYT11 phenotype in this large Dutch pedigree. Depressive and anxiety symptoms are increased in symptomatic, but not in asymptomatic DYT11 MC. Future research has to be carried out to determine whether the psychiatric symptoms are part of or secondary to the DYT11 phenotype.
Departments of *Neurology
‡Clinical Epidemiology, Academic Medical Centre, University of Amsterdam
†Stichting GGZ Buitenamstel-de Geestgronden & Department of Psychiatry, Emgo institute; VU Medical Centre, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
Reprints: Elisabeth M. J. Foncke, MD, Department of Neurology H2-222, Academic Medical Centre, P.O. Box 22660, 1100 DD Amsterdam, The Netherlands (e-mail: e.m.foncke@AMC.uva.nl).
Received for publication August 28, 2008; accepted February 15, 2009
This study was supported by Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) VIDI (project 016.056.333) (E.F. and M.T.).
The authors take responsibility for the integrity of the data and the accuracy of the data analysis.
Disclosure: The authors report no conflicts of interest.