Title: Individual and average trajectories of changes in activities of daily living for autistic individuals by intellectual disability status
Legend: ID: Intellectual Disability, WADL: Waisman Activities of Daily Living Scale
Citation: Hong, J., DaWalt, L. S., Taylor, J. L., Haider, A., & Mailick, M. (2023). Autism through midlife: trajectories of symptoms, behavioral functioning, and health. Journal of Neurodevelopmental Disorders, 15(1), 36. https://doi.org/10.1186/s11689-023-09505-w
Abstract: Background – This study describes change in autism symptoms, behavioral functioning, and health measured prospectively over 22 years. Most studies tracking developmental trajectories have focused on autism during childhood, although adulthood is the longest stage of the life course. A robust understanding of how autistic people change through midlife and into older age has yet to be obtained. Methods – Using an accelerated longitudinal design with 9 waves of data, developmental trajectories were estimated from adolescence through midlife and into early old age in a community-based cohort (n = 406). The overall aim was to determine whether there were age-related increases or decreases, whether the change was linear or curvilinear, and whether these trajectories differed between those who have ID and those who have average or above-average intellectual functioning. Subsequently, the slopes of the trajectories were evaluated to determine if they differed depending on age when the study began, with the goal of identifying possible cohort effects. Results – There were significant trajectories of age-related change for all but one of the measures, although different measures manifested different patterns. Most autism symptoms improved through adulthood, while health worsened. An inverted U-shaped curve best described change for repetitive behavior symptoms, activities of daily living, maladaptive behaviors, and social interaction. For these measures, improved functioning was evident from adolescence until midlife. Then change leveled off, with worsening functioning from later midlife into early older age. Additionally, differences between autistic individuals with and without ID were evident. Although those who have ID had poorer levels of functioning, there were some indications that those without ID had accelerating challenges in their aging years that were not evident in those with ID – increases in medications for physical health problems and worsening repetitive behaviors. Conclusions – Meeting the needs of the increasingly large population of autistic adults in midlife and old age requires a nuanced understanding of life course trajectories across the long stretch of adulthood and across multiple domains. Given the heterogeneity of autism, it will be important not to generalize across sub-groups, for example those who are minimally verbal and those who have above-average intellectual functioning. Keywords – Autism in adulthood, Developmental trajectories, Symptoms, Functioning, Health, Midlife and aging, Accelerated longitudinal design
About the Lab: The Lifespan Family Research program is dedicated to understanding the impact of having a child with a developmental disability on the family as well as the role of the family in supporting healthy development for individuals with disabilities such as ASDs and fragile X syndrome. Smith DaWalt’s work examines trajectories of development for adolescents and adults with disabilities and the contextual factors associated with positive outcomes. Her research also centers on developing and evaluating intervention programming for youth and young adults with ASD. For example, with funding from NIMH, Smith DaWalt is currently conducting a randomized waitlist control trial of a psychoeducation intervention for young adults with ASD and their families. Also, in partnership with colleagues at the University of North Carolina-Chapel Hill and San Diego State University, the lab is employing an implementation science framework to test a comprehensive treatment model for high school students with ASD. This study includes a sample of over 500 students from 60 high schools across the country (including 20 high schools in Wisconsin). Through these efforts, they seek to understand how to best support individuals with disabilities and their families during life course transitions.
Investigator: Leann Smith DaWalt, PhD