Head Injury in Young Children Likely Is a Marker, Not a Cause, for ADHD

Genetics is important in the development of attention-deficit/hyperactivity disorder (ADHD), but the role of other factors — such as maternal drug and alcohol use during pregnancy, other toxin exposures, or injury — is not known. To assess whether head injury is a cause of ADHD, researchers retrospectively analyzed a cohort of 62,088 children from birth to age 10 years who were enrolled in a longitudinal database of 308 primary care practices in the U.K.

ADHD was diagnosed in 934 patients (1.5%) between ages 2 and 10 years. Overall, 2782 children (4.5%) received medical treatment for head injury before age 2, and 1116 children (1.8%) were evaluated for burn or scald injury before age 2. Compared with children without injuries, children in th…