Social avoidance, a common behavior among boys with fragile X syndrome, emerges during infancy, increases in severity across childhood, and stabilizes through adolescence and early adulthood, a study finds.
The complex profile of social avoidance in fragile X was explored by U.S. researchers in the study, “Social Avoidance Emerges in Infancy and Persists into Adulthood in Fragile X Syndrome.” published in the Journal of Autism and Developmental Disorders.
People who experience social avoidance can show a range of behaviors, including inability to initiate interactions, reduced time spent interacting with others, and restricted social interactions to a small group of preferred individuals.
This type of social behavior could be driven by a lack of interest or desire to interact with others, but also can be due to increased discomfort and stress related to social interactions. Regardless of its cause, social avoidance can have a negative impact on a person’s developmental progression and growth.
While social avoidance is a hallmark of fragile X, the age of emergence, and its developmental trajectory, had not been examined.
U.S. researchers believe a better understanding of the profile of social avoidance within this at-risk population may help improve care, with the ultimate goal of overall better long-term outcomes.
“Documenting the developmental trajectory of social avoidance is crucial for promoting both early detection and further understanding regarding the most optimal time to deliver interventions,” they said.
To learn more, the team of researchers evaluated 191 individuals with fragile X, with ages ranging from 4 months to 25 years. Study participants were recruited from three sites: the University of South Carolina, the University of North Carolina at Chapel Hill, and the University of California Davis MIND InstituteU.
A total 81% of participants showed signs of social avoidance, as determined by use of the Social Avoidance Scale (SAS). This high frequency is consistent with previous reports. The incidence of such behaviors remained high even when separately evaluating children (77% affected) and adolescents and young adults (affecting 82%).
Infants and children of preschool age were less likely to show physical movement, drive eye contact, and show facial expressions compared with same age healthy children. Also, while typically developing children tended to improve these social-relation skills with age, fragile X patients progressively lost some of their interactive abilities.
“Infant/preschool-aged males with [fragile X] displayed elevated social avoidance across the majority of scales and … the elevation was evident within the first year of life,” the researchers said. Older fragile X patients also showed higher incidence of social avoidance behaviors compared with age-matched controls.
High eye-contact avoidance nearly doubled across age, with approximately 26% of fragile X adolescents and young adults showing impaired eye contact at both initial social interactions markers — for the first minute of greeting and interaction — and during social interactions.
These results suggest that “social avoidance is a core phenotypic [manifesting] feature of [fragile X],” which “emerges during infancy and increases in severity across early childhood,” the researchers said.
The team believes that evaluating developmental features of social avoidance may help identify later-emerging disorders among fragile X patients, such as social anxiety and autism spectrum disorders, while supporting early therapeutic intervention efforts to manage and prevent the long-term impact of these behavioral symptoms.
An exaggerated “warm up” effect also was observed in fragile X, the researchers said.