CDC Reports Rise in Autism, ADHD

A new study performed by the Centers for Disease Control and Prevention (CDC) reports that the percentage of children and teens in the United States who suffer from a developmental disability, such as autism or Attention Deficit Hyperactive Disorder (ADHD), has risen 17% since the late 1990s.

According to the study authors, this study is the first time nationally representative data on developmental disabilities has been collected since 1988.

The study was performed from 1997 until 2008, and was based on nationally representative health surveys that included personal interviews with roughly 120,000 children nationwide.

The researchers asked parents whether their children had been diagnosed with a developmental disorder such as autism, ADHD, cerebral palsy, learning disabilities, seizures, stuttering or stammering, hearing loss, blindness, or an intellectual disability.

Overall, the number of children reported to have a disability increased from 8.2 million to approximately 10 million; these results indicate that 15% of all children living in the US between the ages of three and seventeen have been diagnosed with a developmental disability.

At the end of the study period (2008), the most common disabilities were ADHD and learning disabilities (7.6% and 7.2%, respectively).

Reports of autism increased from 0.19% in 1997 to 0.75% in 2008.

The increase in the number of reported developmental disabilities over the last decade could be explained by increased awareness on the part of the public and health care professionals of conditions such as autism and ADHD.

Sheree Boulet, one of the study's authors and an epidemiologist at the CDC National Center on Birth Defects and Developmental Disabilities, suggested that the common knowledge of ADHD coupled with the availability of early and effective treatments for such conditions could be encouraging more parents to screen their children for the disorder.

On the other hand, this increase may be an authentic rise in developmental disabilities in children.

Researchers stated that cultural changes that have occurred over the last 10 years include having children later in life, elective C-sections (resulting sometimes in premature births), and a growing trend of using fertility treatments, all of which are associated with increased risk for developmental disabilities and all of which could be contributing to the high rates reported in this study.

The findings "suggest that there are some more prevention strategies that could be put into use," Boulet stated.

Further, the differences in diagnosis rates across economic, ethnic, and gender lines were profound, according to Boulet.

The report of disability in boys was double of what it was in girls; the study authors observed that this may be due to the fact that some genetic disabilities are more likely to be inherited by males, but it is also possible that the symptoms of ADHD and other disabilities are more obvious in boys and are prone to be diagnosed more frequently than in their female counterparts.

Children from low-income families and children on Medicaid had considerably higher rates of developmental disorders than children of higher-income families.

Children from Hispanic families reported lower rates of disabilities than black or white children, but this could be a reflection of language and cultural barriers to accessing health services rather than the true rate of disability.

Whatever the cause for the increase of these disabilities, Boulet and her colleagues agree that the findings indicate an intensifying need for specialized health and social services in order to provide appropriate medical services to the 15% of children in the United States who fall into this category.

The study appears in the June issue of Pediatrics.