Behavior and Emotional Problems in Prader-Willi Syndrome: Comparisons to Autism and Williams Syndrome 

Anastasia Dimitropoulos, Cheryl Klaiman, Joel Bregman, Barbara Pober, and Robert Schultz. Yale Child Study Center, Yale University School of Medicine, 230 South Frontage Road, Box 207900, New Haven, CT 06520-7900.

Introduction:  Research to date on Prader-Willi syndrome indicates that individuals with the disorder suffer from maladaptive behaviors including among others, compulsions, self-injury, and explosive behavior. Multiple studies over the past decade have sought to characterize the behavioral phenotype of this disorder in the hopes of mapping these profiles to the PWS genotype.  In light of findings over the past few years linking autism to chromosome 15 genetic markers, identifying the commonalities between autism and PWS has become of interest.  Although it is uncommon for children with PWS to be clinically diagnosed with autism, similarities between the disorders may lead to a better understanding of the PWS behavioral profile. The purpose of this research is to further examine the emotional and behavioral profile of Prader-Willi syndrome in comparison to individuals with autism and individuals with Williams syndrome. This research is part of a larger project which aims to characterize the neuropsychological and psychiatric phenotype of the three developmental disorders. 

Method:  Thus far, parents of 27 individuals with PWS, 13 individuals with an autism spectrum disorder, and 42 individuals with Williams syndrome between the ages of 10 and 35 have participated in this research.  Emotional and behavior problems were measured using the Developmental Behavior Checklist (DBC; Einfeld & Tonge, 1994). The DBC was developed for use with people with developmental disabilities and has been shown to possess good psychometric properties. Intellectual functioning and adaptive functioning was assessed using the Wechsler Intelligence Scales (WISC or WAIS-III) and the Vineland Adaptive Behavior Scales. 

Results and Discussion:  Preliminary analysis of DBC items indicates that individuals with PWS exhibit emotional and behavior problems more similar to people with autism spectrum disorders than to individuals with Williams syndrome, (DBC total behavior problem score: F(2, 81) = 12.334, p <.001).  Both the PWS and autism groups exhibited means above the critical value for significant behavior problems. In addition, individuals with PWS had higher scores on the antisocial behavior subscale than both participants with autism and Williams syndrome (F(2, 81) = 10.786, p <.001). Similarities found between PWS and autism during individual item analyses will be discussed. In addition, findings from the DBC will be discussed in relation to repetitive behaviors and sensory sensitivities that were assessed using a comprehensive inventory of behaviors including compulsions, restricted activities, impulsivity, and sensory sensitivities.

July 2003