Researchers have revealed that exposure to increased allergen levels in home may trigger asthmatic symptoms in allergic individuals.
The team, at the National Institute of Environmental Health Sciences (NIEHS), the University of Iowa, Rho Inc., and the Constella Group analysed the data from National Survey of Lead and Allergens in Housing (NSLAH) and examined the factors contributing to elevated allergen levels in homes and its association with the individual's asthma status.
"Indoor allergen exposures are of great importance in relation to asthma because most people spend a majority of their time indoors, especially at home," said Dr Darryl Zeldin, researcher in the Laboratory of Respiratory Biology at NIEHS and senior author on the paper.
The indoor allergens studied included those from dog, cat, mouse, cockroach, dust mite, and the fungus Alternaria.
The findings revealed that exposure to indoor allergens was common in U.S. households with 52 percent having at least six detectable allergens and 46 percent having three or more allergens at increased levels.
The study suggests that asthma patients with allergies may ease symptoms by reducing allergen exposures inside their homes.
The study also found that the homes with children were less likely to have high allergen levels, as homes are more frequently cleaned than those without children.
Paivi Salo, of NIEHS and lead researcher of the study, said that the findings have important implications for asthma patients.
"Our results highlight the importance of reducing exposure to allergens as a fundamental part of asthma management," she said.
"Although homes cannot be made allergen free, asthmatics that have allergies may need to do a better job in reducing allergen levels in their homes to improve asthma control," she added.
Researchers suggest that regular household cleaning is a simple and effective regimen that would reduce the overall allergen exposure.
The study is published online and available in the March issue of the Journal of Allergy & Clinical Immunology.