Children aged 9 to 10 years with attention-deficit hyperactivity disorder (ADHD) differ modestly from their unaffected peers in structural brain MRI measures, according to a study published in The Lancet Psychiatry.
Joel Bernanke, M.D., from New York State Psychiatric Institute in New York City, and colleagues conducted a cross-sectional study using baseline demographic, clinical, and neuroimaging data from the Adolescent Brain and Cognitive Development Study, which recruited children aged 9 to 10 years between Sept. 1, 2016, and Aug. 31, 2018.
Cohen’s d values associated with ADHD were estimated for 79 brain measures of cortical thickness, cortical area, and subcortical volume measures. Data were included for 10,736 participants, of whom 949 met criteria for ADHD and 9,787 did not.
After false discovery rate correction, the researchers identified only 11 significant differences across the 79 brain measures in the full model, which included potential confounding variables selected a priori; all indicated reductions in brain measures for participants with ADHD. Cohen’s d values ranged from –0.11 to –0.06 and were not meaningfully altered using a more restrictive comparison group or alternative diagnostic methods.
“It’s important to note that ADHD can be impairing,” a coauthor said in a statement. “Treatments help with that. And while we don’t have good evidence of structural differences appearing in MRI scans, that could well speak to the limitations of the technology, not of ADHD being outside of biology.”
One author disclosed financial ties to the biopharmaceutical industry.