Nationwide U.S. birth cohort study finds marked racial disparities in diagnosis and treatment of ADHD

OptumLabs Data Warehouse maintains a very large database of enrollment records for U.S. commercial health insurers, as well as medical and pharmacy claims related to those clients.

A team of Mayo Clinic researchers accessed that database to examine a nationwide cohort of children born from 2006 through 2012, and who had continuous insurance coverage for at least four years from birth. In the analysis of psychiatric comorbidities and ADHD treatment in the first year after initial diagnosis, only children with at least a year of insurance coverage beyond the ADHD diagnosis were included.

The resulting cohort comprised almost a quarter-million (238,011) children, 49% of whom were girls. The racial/ethnic composition was 72.7% White, 9.8% Hispanic, 6.7% Asian, 6.2% Black, and 4.6% other or unknown.

About 5% of the children who had a diagnosis of ADHD have been made by pediatricians, with the remainder primarily by psychologists, family practice providers, psychiatrists, and neurologists. ADHD diagnoses conformed to standards set in the ninth or tenth revisions of the International Classification of Diseases (ICD-9, ICD-10).

Rates of diagnosis in the U.S. Midwest and West significantly trailed rates in the Northeast and South. Rates also rose steadily with lower household incomes, with children in households with under $40,000 annual incomes being 57% more likely to be diagnosed with ADHD than those with household incomes over $200,000.

After adjusting for sex, region, and household income, Black children were 17% less likely to be diagnosed with ADHD, relative to White children. Hispanic children were 23% less likely to be diagnosed, other/unknown children 27% less likely, and Asian children a staggering 52% less likely.

Both before and after diagnosis of ADHD, Asian children were between two and three times as likely as any other children to be diagnosed with an autism spectrum disorder. White children were more likely to be diagnosed with anxiety disorders. There were no significant differences in the frequency of depressive disorders, disruptive disorders, or oppositional defiant disorder.

After adjusting for sex, census region, and annual household income, White children were also significantly more likely to receive treatment within the first year following diagnosis of ADHD. Black children were 21% less likely to receive treatment, other/unknown children 31% less likely, and Hispanic and Asian children just over half as likely.

The authors noted, “The cause of the disparities in ADHD diagnosis according to race and ethnicity is not fully understood.” They thought it “likely that patients’ concerns about racism play some role in influencing their willingness to approach the healthcare system.” Furthermore, “Health care professionals may also contribute to the racial disparities in diagnosis and treatment. Stereotypes and bias, both explicit and implicit, have been increasingly recognized as factors potentially contributing to physicians’ clinical decision-making. It is possible, for example, that identical behavior displayed by Black and non-Hispanic White children may be interpreted differently based on race-based expectations for the behavior of children, and thus, behavior that is identified as disordered in White children might be inappropriately interpreted as normal in Black children.”

They concluded, “Future study is needed to elucidate the mechanism behind these disparities. Clinicians should provide racially and culturally sensitive care in the evaluation and treatment of ADHD to ensure all children receive appropriate care.”

Yu Shi, Lindsay R. Hunter Guevara, Hayley J. Dykhoff, Lindsey R. Sangaralingham, Sean Phelan, Michael J. Zaccariello, David O. Warner, “Racial Disparities in Diagnosis of Attention-Deficit/Hyperactivity Disorder in a US National Birth Cohort,” JAMA Network Open(2021), 4(3):e21032,