A model to characterize psychopathological features in adults with Prader-Willi syndrome.

High prevalence of behavioral and psychiatric disorders in adults with Prader-Willi Syndrome (PWS) has been reported in last few years. However, data are confusing and often contradictory. In this article, we propose a model to achieve a better understanding of the psychopathological features in adults with PWS. The study is based on clinical observations of 150 adult inpatients, males and females. Non-parametric statistics were performed to analyse the association of psychopathological profiles with genotype, gender and age. We propose a model of psychiatric disorders in adults with PWS based on cognitive, emotional and behavioural issues. This model defines four psychopathological profiles: Basic, Impulsive, Compulsive, and Psychotic. The Basic profile is defined by traits and symptoms that are present in varying degrees in all persons with PWS. In our cohort, this Basic profile corresponds to 55% of the patients. The rest show, in addition to these characteristics, salient features of impulsivity (Impulsive profile, 19%), compulsivity (Compulsive profile, 7%), or psychosis (Psychotic profile, 19%). The analysis of factors associated with different profiles reveals an effect of genotype on Basic and Psychotic profiles (Deletion: 70% Basic, 9% Psychotic; Non-deletion: 23% Basic, 43% Psychotic) and a positive correlation between male sex and impulsivity, unmediated by sex hormone treatment. This is a clinical study, based on observation proposing an original model to understand the psychiatric and behavioural disorders in adults with PWS. Further studies are needed in order to test the validity of this model.