PERSONALITY-PATTERNS IN PATIENTS WITH MYOTONIC-DYSTROPHY

Background: Myotonic dystrophy (DM) is a multisystemic disease. The ce ntral nervous system is affected by cognitive, affective, and personal ity disturbances. A characteristic behavior was noted from the first c linical descriptions, but no definitive conclusions have been drawn de spite extensive debate. As DM is a genetic disease of well-defined abn ormality, it may be a good model for understanding the relative contri butions of nature and nurture in the building of personality traits. O bjective: To investigate the possibility that there is a personality p attern that is characteristic of patients with DM. Subjects and Method s: The personalities of 15 adult (age range, 20-53 years) patients wit h DM with no, or minimal, muscle weakness were studied by means of the International Personality Disorder Examination. The results were comp ared with those from 14 matched healthy subjects (age range, 20-54 yea rs) and 12 patients (age range, 22-50 years) with a mild form of facio scapulohumeral dystrophy. Setting: The Department of Neuromuscular Dis eases, Hopital de la Salpetriere, Paris, France. Results: Patients wit h DM exhibited a homogeneous personality profile, with statistically s ignificant differences (P<.005) for avoidant, obsessive-compulsive, pa ssive-aggressive, and schizotypic traits. In both groups of controls, the personality profiles were extremely heterogeneous. Personality dis orders (avoidant personality) were found in 4 of 15 patients with DM. Conclusions: The findings of this study suggest that the personality p attern of patients with DM is related to their disease. Their personal ity disorders are not attributable to their adjustment to a disabling condition. By contrast, among the patients with DM, the high incidence of avoidant personality, a phenotype poorly represented in the genera l population, supports the idea that it is the expression of a primary phenomenon related to a genetic mutation.