he national prevalence of parent-reported asthma, attention-deficit hyperactivity disorder (ADHD), and autism spectrum disorder (ASD) is on the rise in the United States, as are accompanying comorbid disorders, but poverty influences the prevalence of each of these conditions differently, according to a longitudinal analysis of the National Survey of Children’s Health (NSCH). The study was published online February 13 in Pediatrics.
“[W]e conducted a data analysis using the 3 waves of the [NSCH] from 2003 through 2012,” Christian Pulcini, MD, from the Children’s Hospital of Pittsburgh of University of Pittsburgh Medical Center in Pennsylvania, and colleagues write. “Within this study’s time period, there was a rise in parent-reported lifetime prevalence of all 3 target disorders.”
Specifically, between 2003 and 2011-2012, the relative increase in lifetime prevalence of asthma was 18%, it was 44% for ADHD, and it was almost 400% for ASD.
Table. Lifetime Prevalence of Three Target Conditions
|2003||2007||2011 – 2012|
However, “the increases in lifetime prevalence of these disorders were differentially influenced by poverty status,” investigators write.
For example, increases in asthma prevalence were highest among poor children. Among those who were living under the federal poverty level (FPL), there was a 25.8% increase in asthma prevalence between 2003 and 2011-2012. In comparison, there was only a 13.4% increase in childhood asthma among children living in households with incomes 400% or higher above the FPL.
Asthma was also far more likely to affect uninsured children: it increased by 57.9% for uninsured vs 9.4% among privately insured children.
A similar pattern was seen with ADHD. Specifically, children who were living under the FPL had a 43.2% relative increase in the prevalence of ADHD between 2003 and 2011-2012 compared with a 33.4% increase among children who lived in the wealthiest households. Among uninsured children, there was a relative increase of 42.7% in the prevalence of ADHD vs a 37.5% increase among children who were privately insured across the same survey interval.
“In contrast, increases in the lifetime prevalence of ASD were more prominent among the groups with more financial resources…and those with private insurance,” investigators observe.
For example, between 2007 and 2011-2012, there was a 36.0% relative increase in the lifetime prevalence of ASD in children living in the wealthiest households compared with only about a 13.3% increase in children living below the FPL.