Hispanic Children Focus of New Study on Developmental Delay and Autism

Hispanic children have had a lower rate of autism than other children -- although their cases tend to be more severe. Researchers had wondered -- is there something protective about being Hispanic? Or is this a case of lack of access and lack of understanding of warning signs?

I think you can guess the answer. But proving it is generally better than guessing.

In one of the largest studies so far to compare development in Hispanic children and non-Hispanic children, researchers at the UC Davis MIND Institute wrote that Hispanic children "displayed more similarities than differences compared to non-Hispanics." In the case of autism, they found that rates of autism were actually roughly the same between Hispanic and non-Hispanic children.

The study's lead author, Virginia Chaidez, Ph.D. said the research filled in a piece of "large puzzle" and added "autism is a spectrum and it's very similar across the board. So we're pretty confident in promoting outreach and trying to encourage the Hispanic community to learn the signs very early in life."

Chaidez's paper Autism spectrum disorders in Hispanics and non-Hispanics, was published in the journal Autism. Research was funded by government grants and the MIND Institute.

MIND Institute researchers have been following more than 1,000 children since 2003 as part of the larger CHARGE study (Childhood Autism Risks from Genetics and the Environment). CHARGE children fall into three groups: children with autism, children with developmental delay, but not autism and children enrolled from the general population. While autism is much more about deficits in social interaction and communicating, developmental delay has to do with children who lag in meeting physical or intellectual milestones.

In addition to looking at rates of autism in Hispanic and non-Hispanic children, researchers also looked at comparisons in developmental delay and found some surprises. First, in both Hispanic and non-Hispanic children, nearly one in five children in the developmental delay group actually met the criteria for autism. If parents don't get the correct diagnosis, it's much less likely their children can get the correct treatment.

In addition, 16.5 percent of Hispanic children enrolled from the general population -- "typically developing" -- met criteria for either developmental delay or mixed development, compared with just 2.8 percent of non-Hispanic participants. That's more than a five-fold difference. In the published study, researchers explored many possibilities for this disparity.

One explanation is that children who speak two languages at home tend to test lower at young ages. (This is expected in bilingual or multilingual children -- they generally catch up later.) "Test bias" may have then accounted for some of the difference. On the other hand, researchers wrote that "milder forms of developmental disabilities are more likely to go undetected in Hispanics." Finally, Hispanics may have cultural differences in expectations for child behavior and parenting practices, so diagnosis and treatment may not be sought out.

When Maribel Hernandez of Sacramento noticed something seemed not quite right with her young son, some family members told her not to worry and that he would be fine. Instead, she went to her pediatrician. Her son was diagnosed with autism. After her second son was born, he, too, was diagnosed with the disorder. Hernandez is bilingual and encourages parents -- in both English and Spanish -- to seek out diagnosis and treatment. "They need to ask," she told me, "they need to go and ask for help. If they don't have a chance to go and review what he's supposed to be doing at six months, 12 months, 18 months, if they don't have that chance, then they can't compare with the peers."

Chaidez also encourages parents to be aware of developmental milestones.