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Young children who start school with asthma may lag behind their peers in developing reading skills, a new study suggests.

The findings, according to researchers, do not prove that asthma per se is the reason for the gap. But they say it is possible that the lung disease affects young children's ability to keep up with their peers when it comes to reading.

The study followed 298 New Zealand children through their first year of school. Just over half of the children with asthma had fallen at least six months behind their peers in reading achievement at the end of the year. That compared with a little more than one-third of children without asthma.
The researchers looked at a number of factors that could explain the gap — including the possibility that children with asthma were more likely to be from low-income families, have "poor readiness" for reading or have higher absence rates.

But that was not the case, according to findings published in the medical journal Chest.

"We think our findings suggest that asthma and early reading achievement are linked in some way, which is as yet not explained," lead researcher Dr. Kathleen A. Liberty, of the University of Canterbury in Christchurch, New Zealand, told Reuters Health in an e-mail.

She said she and her colleagues could only speculate on the potential reasons. But one possibility is that breathing problems come into play.

In New Zealand, Liberty noted, children in their first year of school do very little "silent" reading and instead say words and sentences out loud.

"It appears possible that children with asthma may have difficulties controlling their breathing, or learning to control their breathing while reading aloud — which is a part of the reading process that apparently has had little research," Liberty explained.

In contrast, children's early experience with math involves things like writing numbers or matching numbers to pictures of objects. And in this study, children with asthma were not at increased risk of being behind in math ability.

The findings are based on children whose reading and math ability were tested when they entered school and one year later. (In New Zealand, children start first grade when they are 5 years old.)
Just over 18 percent of the children had asthma when they started school. At the end of the year, 51 percent of those children were at least six months behind in reading words, and 55 percent lagged in reading sentences. That compared with 33 percent and 38 percent of children without asthma.

Exactly how asthma might affect children's longer-term school performance is not clear. Liberty said she and her colleagues are continuing to follow the children in this study to find out more about their school achievement.

For now, she suggested that parents of children with asthma be aware that their kids might have difficulty with reading, and then do what's recommended for all parents — support their children's learning.

That includes reading with them at home and communicating with teachers and schools. Schools may offer additional help for children struggling with reading or other skills, Liberty noted.

Another question is whether getting young children's asthma under good control might blunt any negative effects on reading achievement.

Liberty's team did account for the children's asthma severity at the start of the study — which is an indicator of how well their treatment is working. But she said it's possible that their asthma severity changed during the course of the school year.

Further research, Liberty said, might help show whether asthma control has an impact.