Some Children Outgrow ADHD, Imaging Shows
For now, Dr. Rapoport strongly discourages parents from spending money on brain imaging tests to diagnose ADHD. While useful for research, the tests currently available are unlikely to have sufficient sensitivity or specificity “that you would want anyone to pay for,” she said.
“I am sad to see that there are colleagues all over the country … selling, in our already overtaxed health care system, brain imaging tests of various sorts for diagnosis of ADHD,” she lamented.
Dr. Rapoport also questioned whether the findings still to come will render premature the work going into the much-anticipated DSM-V.
She and her colleagues already have a theoretical classification scheme for DSM-VI that incorporates evidence of key cortical milestones occurring early in autism and late in ADHD when compared with normal development.
“At some point, you may be able to argue that brain development trajectories may turn out to be as important as any classification in psychiatry,” she said.
Predicting Schizophrenia in Womb
Prenatal screening based on variations in the numbers of certain key genes might be able to identify the carriers of childhood-onset schizophrenia and other psychiatric disorders, according to Dr. Rapoport.
About 9% of children with childhood-onset schizophrenia have been found to have genetic abnormalities, Dr. Rapoport explained. When children with multiple copies or deletions of key genes are counted, the proportion with possible genetic markers rises to 36%.
Moreover, many of the genes also are implicated in autism. Both conditions are associated with ahead-of-normal brain development, she said, and the timing of certain milestones might determine which of these or other disorders develops. Of note, three children referred to the team as possibly having childhood-onset schizophrenia subsequently developed bipolar disorder instead.
“I think the world is going to be stood on its head diagnostically when these things get sorted out,” Dr. Rapoport said, estimating that as many as 50% of children with early neurodevelopmental abnormalities could have copy number variants.
