Mold in infants' homes can lead to asthma development

August 18, 2011

Two new asthma studies include some practical advice that pediatricians can share with parents. One concerns mold in the home, which can lead to asthma development. Another study offers advice on using air cleaners to control asthma symptoms.

Mold exposure during infancy increases asthma risk, according to a new study, and new parents should be warned to repair water damage or other problems in their homes that could lead to development of mold.

"Early life exposure to mold seems to play a critical role in childhood asthma development," says Tiina Reponen, PhD, lead study investigator and University of Cincinnati professor of environmental health. "Genetic factors are also important to consider in asthma risk, since infants whose parents have an allergy or asthma are at the greatest risk of developing asthma."

For this US Department of Housing and Urban Development-funded study, researchers analyzed 7 years of comprehensive data for 176 children who were part of the Cincinnati Childhood Allergy and Air Pollution Study, a long-term population-based study that included more than 700 children from the Greater Cincinnati area.

The Environmental Relative Moldiness Index (ERMI, a DNA-based analysis tool developed by the US Environmental Protection Agency) was used to measure model levels.

According to study results, 31 of 176 children (18%) were found to be asthmatic at age 7. Children living in a high ERMI-value (≥5.2) home at age 1 year had more than twice the risk of developing asthma than those in low ERMI-value homes (<5.2).

Parental asthma and allergic sensitization to house dust mites also were risk factors, but air conditioning in the home reduced the risk of asthma development. Study results also revealed that the effect of mold was significant for infants but that “a high ERMI value at 7 years of age was not associated with asthma at 7 years of age.”

Another recent study on asthma triggers and prevention found that indoor air cleaners can significantly reduce household air pollution and lower the rates of daytime asthma symptoms to those achieved with some anti-inflammatory asthma drugs. Researchers cautioned, however, that although the air cleaners improved the overall air quality in homes, they did not reduce air nicotine levels and did not counter all detrimental effects of second-hand smoke.

Researchers said that pediatricians should recommend that air cleaners be used temporarily while parents work toward a smoke-free home.

"Air cleaners appear to be an excellent partial solution to improving air quality in homes of children living with a smoker but should not be viewed as a substitute for a smoke-free environment," said lead investigator Arlene Butz, ScD, MSN, CPNP, an asthma specialist at Johns Hopkins Children's Center and professor of pediatrics at the Johns Hopkins University School of Medicine.

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