This study is the first to shed light on how exiting high school – an important turning point in the lives of all youth including those with ASD – impacts the autism behavioral phenotype. Our results are cause for concern. Although autism symptoms and maladaptive behaviors were generally improving while adolescents and young adults with ASD were in the secondary school system, improvement slowed significantly after high school exit for internalizing behaviors and all but one of the autism symptoms subdomains. For each of these subscales, the rate of improvement in symptoms and behaviors was reduced by over one-half after high school exit. Our findings are consistent with previous research examining the impact of turning points for adults with ID (Esbensen et al., 2008
). Parental death and moving out of the parental home was associated with increased maladaptive behaviors for adults with ID; it appears the exiting high school has a disruptive effect in behavioral phenotypic improvement for youth with ASD.
Although there are a number of possible explanations for the slowing in improvement at high school exit, such as slowing of cognitive development or hormonal changes during this time, we find changes in disability-related services the most compelling prospect. In addition to the disruptive effects of changing from school to adult day activities, it is possible that the slowing of improvement in the autism behavioral phenotype following high school exit is reflective of the less stimulating adult occupational and day activities than those experienced in school. Supporting this interpretation, Shepperdson (1995)
found that adolescents with Down syndrome who had less stimulating home environments had poorer language ability and social competence scores.
Contrary to our hypotheses, the most pronounced slowing of improvement after high school exit was observed for young adults with ASD who did not have ID. This stood in contrast to behavioral phenotypic change while these youth were in high school. Consistent with our previous research (Shattuck et al., 2007
), those with ASD who did not have ID improved more in both autism symptoms and maladaptive behaviors while they were in high school compared to those with comorbid ID. After high school exit, however, improvement in symptoms and behaviors slowed more for those without ID, with trajectories that appeared similar to youth with comorbid ID. This suggests that for youth without comorbid ID, high school exit appeared to have a more pronounced influence on their autism symptoms and behavior problems over time.
The disruptive influence of high school exit for young adults without ID may be related to difficulties finding appropriate educational and occupational activities after exit. Taylor and Seltzer (under review) found that nearly three-fourths (74%) of young adults with ASD and comorbid ID were receiving adult day services in the years immediately following high school exit compared to only 6% of those without ID. Furthermore, over one-quarter of young adults with ASD without ID had no occupational, educational, or day activities at this time, a percentage that was over three times greater than youths with comorbid ID. In sum, it appears that the adult service system may not provide adequate opportunities for adults with ASD who do not have comorbid ID to achieve maximum levels of independence and find employment activities appropriate to their interests and level of functioning. The lack of stimulating activities after exit may be at least in part responsible for the slowing of improvement of the autism behavioral phenotype observed while these youth were in high school. Future research should explore this issue directly by examining the relations between appropriate, stimulating adult daytime employment and activities and changes in the behavior phenotype from before to after high school exit.
If the relations between high school exit and slowing improvement are indeed due to an inadequacy of services after exit, findings from the present study would have important implications for developing more effective adult services and stimulating job opportunities for youth with ASD – particularly those without ID. Although there are a handful of model programs that include services for transition-aged youth with ASD without ID (such as the Kelly Autism Program at Western Kentucky University), these programs are inaccessible to the majority of families. Employment-related programs that consider the interests and specific needs of all youth with ASD, and that provide appropriate and meaningful supports to those without ID may encourage continued phenotypic improvement after these youth exit high school.
Our analyses also suggest that improvement in maladaptive behavior slows more for those young adults with ASD whose families have lower incomes compared to families with higher incomes. Although lower socio-economic status (SES) is an important and well-identified risk factor for poor physical and psychological health among the general population (Marmot, Ryff, Bumpass, Shipley, Marks 1997
; Ryff & Singer, 1998), it has largely been overlooked in studies of individuals with ASD and their families. The few studies that have examine the impact of SES in autism samples find that families who have lower incomes or less parental education have less access to autism-related services in early childhood than families who have more socio-economic resources (Liptak et al., 2008
; Thomas et al., 2007
). Therefore, our findings of slowed improvement in maladaptive behaviors after high school exit for those from lower income families may reflect an income disparity in the availability and quality of adult services.
Perhaps most interesting, family income was unrelated to initial severity of maladaptive behaviors or improvement in maladaptive behaviors while individuals with ASD were in the secondary school system – income was instead only related to change after high school exit. This may indicate some degree of success of the Individuals with Disabilities Education Act (IDEA), which mandates appropriate educational services for all school-aged children with disabilities. Assuming that better services are related to behavioral phenotypic improvement, the lack of relations between income and improvement while in high school may reflect autism services through the school system that differ little based on parental SES. Following this line of reasoning, however, also suggests that income may have a large effect on service availability after youth with ASD exit the school system. Higher parental income has been shown to “smooth the way” for typically developing youth who are transitioning to adulthood (Galambos et al., 2006
) and future research should study whether higher parental income also promotes a smoother transition to adulthood for young adults with ASD.
Not only do our findings have important implications for individuals with ASD who are transitioning out of the school system and their subsequent adult services, but also for their families during this time. Although research findings are mixed regarding the relations between autism symptoms and family well-being (Benson, 2006
; Tobing & Glenwick, 2002
), a well-established body of research suggests that maladaptive behaviors are among the most difficult aspects of caring for a son or daughter with ASD (Hastings, 2003
; Hastings & Brown, 2002
; Tomanik et al., 2004
; Lecavalier et al., 2006
). Families may have become accustomed to improvement in maladaptive behaviors while their son or daughter was in the secondary school system, and slowing of improvement after high school exit occurs at the same time that parents begin assuming the role of service coordinator for their son or daughter (Howlin, 2005
). The situation becomes potentially more serious when considering that all of this change is occurring among families that tend to be more stressed throughout the life course than families of children with any other developmental disorder (Bouma & Schweitzer, 1990
; Donovan, 1988
; Dumas, Wolf, Fisman, & Culligan, 1991
; Holroyd & McArthur, 1976
; Rodrigue, Morgan, & Geffken, 1990
; Wolf, Noh, Fisman, & Speechley, 1989
). Therefore, future research should consider how exiting high school impacts the well-being of families of transition-aged youth with ASD.
There are three limitations to the present study that are worth noting. First, the sample in the larger study was a volunteer sample, most of the sample members were Caucasian, and the sample was skewed toward those with higher SES. These factors place limits on the generalizability of the results to non-White and lower SES populations. Second, because this was not an experimental study, it is impossible to determine whether exiting high school is the causal factor in symptom and behavior change. Although we ruled out moving from the parental home concurrent with exit as a competing explanation, there could be a number of other factors associated with this developmental stage (e.g., slowing of cognitive development, hormonal changes) causing slowing in improvement of the autism behavioral phenotype. Finally, we were unable to examine the quality of services within the school system or after high school exit in relation to change in the autism behavioral phenotype. It may be that those young adults who received high quality services while in school and lower quality services after exit may experience more phenotypic change compared to young adults who receive higher quality services both before and after high school exit.
These limitations are offset by a number of strengths. This is the first longitudinal study to follow adolescents and young adults with ASD from before to after high school exit, allowing us to prospectively examine how this turning point is associated with behavioral functioning. Although there are limits to its generalizeability, our sample was relatively large and recruited from the community, making our findings more generalizeable than many other studies of individuals with ASD. Finally, this is the first empirical study to suggest that exiting high school is a disruptive influence in the lives of youth with ASD. Because we know that the transition out of high school does not happen in a vacuum, future research should integrate multiple levels of analysis such as change in biological functioning, services, and family functioning in order to fully understand how individuals with ASD experience the transition out of high school and into adulthood.