Regional Variations in the Prevalence and Median Age of Diagnosis of Autism Spectrum Disorder in Arkansas

Poster Presentation
Saturday, May 4, 2019: 11:30 AM-1:30 PM
Room: 710 (Palais des congres de Montreal)
S. B. Smith1, M. Lopez2, T. M. Baroud3, A. E. Hudson4 and Y. D. Schwenk4, (1)Developmental Behavioral Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR, (2)Section of Developmental-Behavioral Pediatrics and Rehabilitation Medicine, UAMS, Little Rock, AR, (3)UAMS, Little Rock, AR, (4)Pediatrics, UAMS, Little Rock, AR

The Autism and Developmental Disabilities Monitoring (ADDM) Network gathers data on Autism Spectrum Disorder (ASD) and other developmental disabilities in multiple sites, including Arkansas (AR), in the United States. The AR ADDM data shows a higher median age of diagnosis (SY 2002, 2010 and 2014) and a lower identified prevalence of ASD compared to the ADDM Network average 2014.

Objectives: Given that AR is a largely rural (non-urban) state, we suspect that children living in non-urban areas have more difficulty accessing healthcare resources compared to urban areas. We hypothesize that the identified prevalence of ASD is lower for children in non-urban areas and the median age of diagnosis is higher for children in non-urban areas.

Methods: AR ADDM data was collected statewide for study years (SY) 2002, 2010 and 2014. The methodology is modeled on a standardized retrospective record review created by the CDC’s Metropolitan Atlanta Developmental Disabilities Surveillance Program (MADDSP). Counties were then categorized into urban versus rural (non-urban) areas for comparison based on U.S. Census Data. Data analyzed included prevalence (subdivided by race and ethnicity) per 1000 of 8-year-old children diagnosed with ASD and the median age (in months) at earliest evaluation confirming an ASD diagnosis.

Results: The identified prevalence of ASD was significantly higher in urban areas compared to non-urban areas for the total population in SY 2010 and 2014. When looking at the different racial/ethnic groups, this trend is also true for Non-Hispanic Whites in SY 2010 and 2014 but not for other racial/ethnic groups. There was no significant difference in identified prevalence between Black Non-Hispanics and Hispanics (of any race) living in urban and in non-urban areas for any study year. There was no significant difference in median age of diagnosis in non-urban versus urban areas for 2002, 2010 and 2014 for the total population.

Conclusions: The data supports the hypothesis that there is a lower identified prevalence for children in non-urban areas compared to urban areas overall in 2014 (but not in 2010). This is likely due to differences in identified ASD prevalence in non-urban versus urban areas in the White population. The majority of children in Arkansas (as well as this study) are White. This would explain why differences in non-urban versus urban areas in this group greatly impact the total population. Furthermore, there was a much smaller number of Non-Hispanic Black and Hispanic children in the study which may affect why a significant difference was not observed. The data does not show a difference in median age of diagnosis for children in non-urban areas versus non-urban areas for the total population. This study is limited by incomplete race/ethnicity data for SY 2014 (Approx. 15% in Other, Missing, Unknown) and incomplete access to educational data in non-urban counties (but not urban areas) for SY 2014. Further studies are needed to determine contributors to the regional differences, such as migration patterns and limited access to healthcare providers, noted in this study.