Overactivity, impulsivity and repetitive behaviour in males with fragile X syndrome: contrasting developmental trajectories in those with and without elevated autism symptoms

Abstract

These results further understanding of the relationship between autistic phenomenology and behavioural characteristics in FXS.

Delineating Repetitive Behavior Profiles across the Lifespan in Fragile X Syndrome

“…Recently, Moskowitz et al [4] utilized longitudinal models to examine RRBs through adolescence in males and females with FXS. Results suggested the developmental stability of more complex forms of RRBs (Restricted Interests, Compulsive, and Ritualistic/Sameness behaviors) aligning with previous findings suggesting individuals with FXS exhibit a minimal change in RRBs across time [30] and chronological age [2,3,31].…”

“…When considering the impact of ASD diagnosis on the RRB profile of FXS, the same core problems were reported in individuals with FXS and ASD (e.g., Restricted Interests, Sensory-Motor, and Ritualistic/Sameness behaviors being most problematic) as the overall sample; however, the severity of these problems almost doubles in comparison to individuals with FXS only, with significant differences emerging across all of the RBS-R subscales. These findings build on the premise that although these problems may be core to the FXS behavioral phenotype, the added diagnosis of ASD increases the risk for more problem behaviors in FXS including increased RRBs [12,15,30,31]. These findings suggest the RBS-R may be a valid measure for differentiating individuals with FXS who have ASD in comparison to those without ASD based on severity of ratings.…”

“…Although the presence of RRBs are core to the diagnosis of ASD, they are also quite common in typically developing children and have been found in a variety of other clinical and neurodevelopmental disorders, including FXS. At the global level, individuals with FXS are known for exhibiting RRBs, with a unique RRB profile being observed across the preschool years through adolescence [2][3][4], with developmental stability across time [30] and age [2][3][4]31]. To date, there has been little work examining the FXS RRB profile across the lifespan through adulthood, with limited information about the female RRB profile [4,26].…”

The Persistence of Self-injurious and Aggressive Behavior in Males with Fragile X Syndrome Over 8 Years: A Longitudinal Study of Prevalence and Predictive Risk Markers

“…However, inconsistent results have also been reported regarding the persistence of some social behaviors associated with ASD with both subtle improvements (McDuffie et al 2010) and increasing impairment (Thurman et al 2015) being reported with age. In addition, our recent research demonstrated an improvement in impulsivity and repetitive questioning in males with FXS who did not have elevated autism symptoms (Crawford et al 2018).…”

“…Similarly, the presence of ASD is also elevated with a 30% prevalence rate in FXS (Richards et al 2015) compared to 1% of the general population (Baird et al 2006). The current literature suggests that many behaviors associated with both ADHD and ASD remain largely stable over time in individuals with FXS (Crawford et al 2018; Hatton et al 2002; McDuffie et al 2010; Thurman et al 2015). However, inconsistent results have also been reported regarding the persistence of some social behaviors associated with ASD with both subtle improvements (McDuffie et al 2010) and increasing impairment (Thurman et al 2015) being reported with age.…”