A Longitudinal Evaluation of Restricted Behaviors and Sensory Interests in Angelman's Syndrome Using the Behavior and Sensory Interests Questionnaire

Background:  Angelmans Syndrome (AS) is a neuro-genetic disorder characterized by severe intellectual and developmental disability.  Clinical reports have described a high level of sensory interests and repetitive behaviors (RRB) in AS, though there has been a paucity of research in this area. Currently only a single study (Walz, 2007) using the Gilliam Autism Rating Scale, has looked at RRBs in this population.  However, Richler et. al (2010) examined how restricted and repetitive behaviors and interests (RRBs) developed over time in a sample of children with ASD. For children with ASD, RSM scores remained relatively high over time whereas IS scores started low and increased over time.  In addition, having a higher nonverbal intelligence (NVIQ) at age 2 was associated with improvement in RSM behaviors over time.  There was no relationship between NVIQ at age 2 and IS behaviors.  

Objectives:  The current study describes the type, number and intensity of RRB’s in large AS population over a four year time period, using a newly standardized scale, the Behavior and Sensory Interest Questionnaire (BSIQ) to describe these behaviors.

Methods:  A sample of 152 (50.7% female) children ranging from age 36-209 months (mean 84, SD 42).  Participants were drawn from an eight year longitudinal study.  Subjects were followed from 1 to 4 years.  The BSIQ, a newly standardized interview based measure designed to evaluate the number, type, and intensity of a comprehensive array of RRBs was administered to all parents (Hanson et al, submitted). Children also received additional cognitive and behavioral testing.  

Results:  This is the first study to take a comprehensive look at RRB behaviors in an AS population. Of the behaviors exhibited, 85% were RSM behaviors and 15% were IS behaviors.  Analysis showed that the majority of children (94%) with AS exhibited at least 1 RRB.  High percentage of flapping behavior exhibited; heterogeneous among all IQ groups (range of 53-88%).  This is consistent with Walz 2007 which also found a commonality between flapping behaviors (56%) in individuals with AS.  Analysis is ongoing for the longitudinal trajectory of these behaviors as well as the impact of cognitive ability. 

Conclusions:  Implications suggest that providers should be aware of the high prevalence of behaviors in individuals with AS and the possibility that these behaviors can impact current and future functioning of children with AS as well as have a negative impact on family members.   Future research is needed to explore and confirm these findings. In addition, these behaviors should also be compared to those children with other developmental issues, such as ASD.