Examining Trends and Coexisting Conditions Among Children Qualifying for SSI Under ADHD, ASD, and ID.

Objective: To examine the prevalence trends and coexisting conditions in attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and intellectual disability (ID) in the pediatric Supplemental Security Income (SSI) population and general population.

Methods: The Social Security Administration (SSA) provided data on primary and secondary diagnoses of children qualifying for SSI for years 2000 to 2011. We compared SSA data with 2000-2011 National Health Interview Survey data on the prevalence of mental health diagnoses among children in the general population living between 0 and 199% of the federal poverty line. We utilized linear regression analysis to test the statistical significance of differences in the trends of the conditions' prevalence.

Results: Over this time period, the SSI population experienced increases in ADHD (5.8%) and ASD (7.2%) and a decrease in ID (-10.3%). Comparison with change in the general population indicated no significant difference in ADHD but significant differences in ASD and ID. Relative percentage changes reflect similar changes. The SSI population qualifying for SSI with ADHD (70.8%) had higher rates of coexisting conditions than the general population (66.1%), but lower rates of coexisting conditions for ASD and ID.

Conclusions: ADHD is on the rise among children receiving SSI and in the general population. This suggests that the rise of ADHD in the SSI population is expected and does not represent a misallocation of resources. Changes described among the SSI population in ASD and ID may allude to diagnostic/coding trends and/or true changes in prevalence. Limitations arise from the comparability of the 2 data sets.