Asthma attacks are a common cause of emergency room (ER) visits among children. Exposure to indoor allergens and irritants like mold, moisture, pests, and tobacco smoke can exacerbate asthma, leading to potentially avoidable ER visits.

Our recent analysis of the 2015 American Housing Survey (AHS) found that more than one-quarter of households with a school-age child (ages 5 to 17) with asthma was exposed to leaks in the past year, which may lead to mold or dampness. Nearly one in five households with a school-age child with asthma was exposed to smoke in the home at least monthly, through smoking by household members, visitors, or residents in other units in the building.

Renter-occupied households with school-age children with asthma were more than twice as likely as owner-occupied households to be exposed to smoke, musty smells, and evidence of cockroaches or rodents at least monthly over the past year.

Among households with a school-age child with asthma, those exposed to smoke in the home at least monthly were more likely to report an ER or urgent care visit for their youngest child with asthma (30.1 versus 18.8 percent), as were those exposed to mold in a bedroom during the past year (44.4 versus 20.2 percent) (figure 1).

We found that the relationship between exposure to smoke and asthma-related ER and urgent care visits persisted after controlling for housing characteristics, household characteristics, householder characteristics, and presence of other asthma triggers. The relationship between exposure to mold in a bedroom and asthma-related ER and urgent care visits also persisted after controlling for these factors.

Although the AHS does not include information about insurance coverage, which is an important missing factor in explaining the variations, our analysis suggests that secondhand smoke and exposure to mold in the bedroom may play a role in pediatric asthma-related ER and urgent care visits.

This study also provides nationally representative estimates of the share of households with at least one school-age child with asthma that were exposed to certain asthma triggers over the past year, which can help target programs to reduce asthma triggers.

How can we reduce exposure to asthma triggers?

Home-based education and asthma trigger remediation can reduce exposure to allergens like mold. Despite the evidence that exposure to tobacco smoke is particularly detrimental for children with asthma, many home-based asthma education and trigger reduction programs do not include parental or household member smoking cessation interventions.

Parents of school-age children with asthma may also face barriers to smoking cessation, including financial barriers or other conditions like depression that make it difficult to quit. Broader access to evidence-based smoking cessation interventions—like medication and counseling through health insurance, such as the Medicaid program, which covers many low-income parents—could help more parents quit.

Broadening insurance coverage for low-income adults through Medicaid improves mental health and could reduce mental health–related barriers to quitting.

Finally, tobacco quitlines, particularly quitlines that offer follow-up counseling calls can reduce smoking and exposure to secondhand smoke.

Among renters in multiunit buildings, pests, mold, and secondhand smoke may be present across multiple units, making them difficult for individual renters or owners in multiunit housing to address. Household-level interventions like home-based asthma education and trigger remediation, which reduce exposure to asthma triggers like mold, may need to be supplemented with broader policy initiatives like smoke-free policies, tobacco quitlines, rental housing inspections, and public housing quality inspections.

The US Department of Housing and Urban Development (HUD) now requires smoke-free policies to be developed and implemented in all public housing, and private landlords can implement such policies. Some local governments have implemented rental property registration and inspection programs, and these programs could be expanded to cover health hazards like mold.

Similarly, mold and other health hazards could be included in HUD’s standards for housing quality inspections of public housing properties and units leased by a household with a rental assistance voucher.

Data from the Healthcare Cost and Utilization Project show that hospitals charged over $807 million for asthma-related ER visits for school-age children in 2014. The costs of asthma morbidity are even higher when considering broader impacts like missed school days for children and missed work days for parents.

Our findings point to a need to consider the whole household—including housing conditions and behaviors of household members, neighbors, and visitors—when exploring programs to reduce ER and urgent care visits among children with asthma and to apply both household-level and broader policy interventions to reduce exposure to indoor asthma triggers among households with school-age children.