Psychiatric and cognitive phenotype in children and adolescents with myotonic dystrophy

Marie Douniol (1, 2) , Aurélia Jacquette (3) , Jean-Marc Guilé (2, 4) , Marie-Laure Tanguy (1) , Nathalie Angeard (3) , Delphine Héron (3) , Monique Plaza (1, 2) , David Cohen (1, 2)

1 CHU Pitié-Salpêtrière [AP-HP]
2 LPNCog / UMR 8189 - Laboratoire de Psychologie et Neurosciences Cognitives
3 Institut de Myologie
4 Centre de recherche Fernand Seguin

Myotonic dystrophy type 1 (DM1) is the most frequent inherited neuromuscular disorder. The juvenile form has been associated with cognitive and psychiatric dysfunction, but the phenotype remains unclear. We reviewed the literature to examine the psychiatric phenotype of juvenile DM1 and performed an admixture analysis of the IQ distribution of our own patients, as we hypothesised a bimodal distribution. Two-thirds of the patients had at least one DSM-IV diagnosis, mainly attention deficit/hyperactivity disorder and anxiety disorder. Two-thirds had learning disabilities comorbid with mental retardation on one hand, but also attention deficit, low cognitive speed and visual spatial impairment on the other. IQ showed a bi-modal distribution and was associated with parental transmission. The psychiatric phenotype in juvenile DM1 is complex. We distinguished two different phenotypic subtypes: one group characterised by mental retardation, severe developmental delay and maternal transmission; and another group characterised by borderline full scale IQ, subnormal development and paternal transmission.

Mots clés: Myotonic dystrophy type 1; Juvenile form; Psychiatric phenotype; Cognitive profile

Marie Douniol, Aurélia Jacquette, Jean-Marc Guilé, Marie-Laure Tanguy, Nathalie Angeard, et al.. Psychiatric and cognitive phenotype in children and adolescents with myotonic dystrophy. European Child and Adolescent Psychiatry, 2009, 18 (12), pp.705-715. ⟨10.1007/s00787-009-0037-4⟩. ⟨hal-00535161⟩