“Clinically, later-born siblings of children with ASD and ADHD appear to be at elevated risk within and across diagnostic categories and thus should be monitored for both disorders,” wrote Meghan Miller, Ph.D., of the University of California, Davis, and colleagues. “Practitioners may wish to share such information with families given the potential relevance of monitoring social communication, attention, and behavior regulation skills in later-born siblings of children with ASD or ADHD.”
Miller and colleagues analyzed patient data from two large U.S. health care systems: Marshfield Clinic, a large regional health care system in the upper Midwest, and Kaiser Pacific Northwest, an integrated health plan in Oregon and Washington. They assessed the outcomes of 15,175 children with older siblings, of whom 730 had an older sibling diagnosed with ADHD and 158 had an older sibling diagnosed with ASD.
Compared with children whose older siblings had neither disorder, children with an older sibling with ASD were about 30 times more likely to also be diagnosed with ASD and 3.7 times more likely to be diagnosed with ADHD. Children with an older sibling diagnosed with ADHD were about 13 times more likely to be diagnosed with ADHD and 4.4 times more likely to be diagnosed with ASD.
“[This study] used a simple and transparent design to report novel data on later-born within- and cross-condition recurrence of ASD and ADHD in a way that is useful in the clinic but also motivates research to understand how and why these conditions commonly co-occur both within individuals and within families,” wrote Tony Charman, Ph.D., of King’s College London and Emily Jones, Ph.D., of the University of London in an accompanying editorial.
To read more about this topic, see the Psychiatric News article “Study Examines Connections Between Psychiatric, Neurological Disorders.”
(Image: iStock/romrodinka)