Longitudinal trajectories of aberrant behavior in fragile X syndrome

Abstract

The Aberrant Behavior Checklist—Community (ABC-C; Aman, Burrow, & Wolford, 1995) has been increasingly adopted as a primary tool for measuring behavioral change in clinical trials for individuals with fragile X syndrome (FXS). To our knowledge, however, no study has documented the longitudinal trajectory of aberrant behaviors in individuals with FXS using the ABC-C. As part of a larger longitudinal study, we examined scores obtained on the ABC-C subscales for 124 children and adolescents (64 males, 60 females) with FXS who had two or more assessments (average interval between assessments was approximately 4 years). Concomitant changes in age-equivalent scores on the Vineland Adaptive Behavior Scales (VABS) were also examined. As expected for an X-linked genetic disorder, males with FXS obtained significantly higher scores on all subscales of the ABC-C and significantly lower age-equivalent scores on the VABS than females with FXS. In both males and females with FXS, scores on the Irritability/Agitation and Hyperactivity/Noncompliance subscales of the ABC-C decreased significantly with age, with little to no change occurring over time on the Lethargy/Social Withdrawal, Stereotypic Behavior, and Inappropriate Speech subscales. The decrease in scores on the Hyperactivity/Noncompliance domain was significantly greater for males than for females. In both males and females, age-equivalent scores on the VABS increased significantly over this developmental period. These results establish a basis upon which to evaluate long-term outcomes from intervention-based research. However, longitudinal direct observational studies are needed to establish whether the severity of problem behavior actually decreases over time in this population.

Fragile‐X syndrome – a 20‐year follow‐up study of male patients

“…When examining medication lists, we were struck by the great number of psychotropic drugs used, especially among individuals who had been living in a nursing home for a lengthy period. On the other hand, in a recent North American study, 62.5% of FXS males aged 2-26 took one or more psychotropic drugs (27). Health problems such as mitral-valve prolapse, strabismus, and epilepsy, presented here, as well as in other studies (6,28,29).…”

Change in the Behavioral Phenotype of Adolescents and Adults with FXS: Role of the Family Environment

“…Not surprisingly, females with FXS were found to have higher levels of adaptive behavior and lower levels of behavior problems and autism symptoms than males, consistent with the milder level of symptoms characteristic of females with FXS (Hustyi, Hall, Jo, Lightbody, & Reiss, 2014; Mazzocco, 2000). Psychotropic medications were prescribed for those who had lower levels of adaptive behavior, and higher levels of behavior problems and autism symptoms.…”

Decreased home cage movement and oromotor impairments in adult Fmr1‐KO mice

“…Interestingly, hyperactivity in males with Fragile X has been shown to change over development with decreased activity in very young children followed by increase in preschoolers followed by decrease in adolescent boys (Tranfaglia 2011; Gabis et al ., 2011; Hustyi et al ., 2014). Although information regarding hyperactivity in adults with FXS is lacking, our data suggest that hypoactivity might be observed in adults with FXS.…”