The number of children with asthma in the United States has been steadily increasing for decades but the trend is now shifting, according to a study carried out by researchers from the National Center for Health Statistics.

According to Lara Akinbami of the National Center for Health Statistics, the results of their study published in the journal Pediatrics surprised her and her colleagues. They were expecting the trend to continue but they saw the opposite after analyzing data from 2001 to 2013 in the National Health Interview Survey.

Based on the results of their research, Akinbami and colleagues saw that asthma prevalence peaked at 9.7 percent for 2009 in children aged 17 years old and below. The trend continued until 2013, when the prevalence rate dropped to 8.3 percent.

Children with asthma in the country doubled in percentage from 1980 to 1995, steadily increasing since then. Researchers are still unclear on what could have led to the spike in cases then but there are several possible factors, like inhalation of secondhand smoke, improper immune system development and obesity.

But despite the shift that the researchers observed, children from poor families continue to develop asthma, with cases more common in African-American children compared to those who are white. Case in point, more than 14 percent of black children have breathing disorder while only about 8 percent of white children have it. Not to mention that black children are also likelier than their white counterparts to suffer from severe complications brought about by asthma.

Akinbami and colleagues are also unsure of what caused the decline but one of the reasons they are looking at is that children genetically susceptible to asthma have already peaked and so their number has started to go down.

Whatever the reason for it, the decline is seen as good news for kids by Stephen Teach, Children's National Health System's chairman of pediatrics, as he sees asthma as both a health care and economic drag on the system. In addition to medically related expenses, the breathing disorder also causes children to miss school and their parents work.

Still, there's a long way to go as about 1 in 9 children still have asthma, according to Elizabeth Matsui, a pediatrics professor from the Johns Hopkins Children's Center.

Aside from Akinbami, Alan Simon and Lauren Rossen also contributed to the study.

Photo: Thomas Widmann | Flickr

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