According to the study results, children born in socio-economic sectors that have a greater proportion of low-income households, higher population densities and greater poverty experienced a higher incidence of asthma.

In addition, black and Hispanic children faced significantly higher asthma risks than white children, regardless of neighborhood, the researchers wrote in the study published in JAMA Pediatrics.

“Although we know that black and Hispanic children have high rates of asthma and that children who reside in neighborhoods with increased poverty also have an increased risk of asthma, few studies have been able to investigate these two risk factors at the same time”, Antonella Zanobetti, PhD, senior researcher in the Department of Environmental Health at the Harvard TH Chan School of Public Health in Boston, Healio told.

Antonella Zanobetti

“We were able to do this because we combined multiple birth cohorts from across the country,” Zanobetti said.

Study results

Researchers examined data from 10 birth cohorts participating in the Children’s Respiratory and Environmental Labor Group, including census tract-level information from 4 census years between 1980 and 2010 on each participant’s birth address .

The asthma analysis included 5809 children, while the analyzes for early wheeze included 5686 children and persistent wheeze included 4789 children.

Health outcomes included incidence of asthma up to age 11 in 24.8% of the population, early wheeze in 45.5% and persistent wheeze in 25.8% .

Children who lived in census tracts with higher poverty rates, lower income, and lower median household income, as well as black children, all experienced early onset asthma, with associations significant between census variables and asthma incidence, the researchers found.

According to the researchers, the incidence of asthma appeared to be significantly higher in black children (HR = 1.47; 95% CI, 1.26-1.73) and Hispanic children (HR = 1.29 ; 95% CI, 1.09-1.53) compared to white children as well as children whose parents had a history of asthma (HR = 2.08; 95% CI, 1.87-2 ,31).

Although the researchers did not consider the interaction between a child’s race and ethnicity and statistically significant census variables, they found that there was an elevated risk of asthma incidence among black and Hispanic children compared to white children in all census tracts.

Similarly, children in areas with higher median household incomes had a reduced risk of early wheeze (OR = 0.94; 95% CI, 0.88-1.01) and persistent wheeze ( OR = 0.89; 95% CI, 0.81-0.96).

Black and Hispanic children had significantly higher ORs for persistent and early wheezing compared to white children, as did children whose parents had a history of asthma and children of mothers who smoked during pregnancy.

Consequences

Overall, black and Hispanic children were more likely to live in neighborhoods that had higher population densities and higher poverty rates, the researchers found, and children born in census tracts with higher levels of poverty and lower household income were at high risk for childhood wheeze and asthma. .

However, the researchers continued, race and ethnicity persisted as risk factors when neighborhood income was taken into account, indicating that structural inequalities increased the risks of wheezing and asthma in residing Black and Hispanic children. in rich and poor neighborhoods.

“We were surprised that after taking into account both neighborhood characteristics and individual risk factors for asthma, such as having a parent with asthma, black and Hispanic children continued to have an increased risk of asthma. compared to white kids,” Zanobetti said.

Although the complexity of multiple individual-level and neighborhood-level factors makes it difficult to define the root causes of these disparities, the researchers wrote, structural and social determinants can include racism, discrimination, discriminatory policies, education, the physical environment and access to health. care.

Physicians and other stakeholders can act at the individual and system levels to improve care, Zanobetti said.

“Physicians can learn about neighborhood, home, and school-related asthma risk factors, educate vulnerable patients about potentially fixable risk factors, and ask if they have any outdoor neighborhood exposures. or indoors that can increase the risk of asthma,” Zanobetti said.

If risk factors are identified, she continued, doctors might have the ability to prescribe housing changes or advocate for neighborhood and housing improvements.

Additionally, she said, hospitals, doctors and other healthcare workers can work within their own systems to provide equal access to excellent healthcare, including medicines for all.

“This requires training to reduce implicit and explicit racial or ethnic bias in health care and increase the hiring of diverse, culturally competent staff,” Zanobetti said.

Finally, she added, doctors can work as citizens for environmental justice in all communities, including their own.

“Our findings really underscore that addressing health inequalities requires not only individual-level changes in practice, but also large-scale population-level changes,” Zanobetti said.

“Housing conditions, environmental exposures and access to care are all likely contributors to our findings. But on top of that, racism, both individual and institutional, can also contribute to health inequalities,” she said.

While the researchers recommended observational studies that could identify these risk factors and guide interventions and policies to mitigate them, an editorial that accompanied the study called for a fundamental shift in research priorities.

Structural solutions and policy changes will be needed to mitigate these racial disparities in asthma risk, Daniel T MalleskeMD, MS, an attending neonatologist at Children’s Hospital of Philadelphia and his colleagues wrote in the editorial.

Funding previously earmarked for observational studies should instead support quasi-experimental trials to assess interventions designed to mitigate the ongoing association between historic redlining and modern housing quality, homeownership, and environmental pollutants with the risk of asthma and disease, they wrote.

Calling the root causes of racial disparities very well documented, the editorial authors concluded that programmatic and legislative policies and interventions that target these causes must be rigorously and scientifically evaluated and disseminated.

Meanwhile, Zanobetti and his colleagues plan to continue their research.

“We are now exploring other factors that may have contributed to these results. For example, environmental exposures like air pollution may play a role in the disparities,” she said.

“We are also looking at historic policies like redlining that contribute to the current segregation and concentration of poverty in many areas,” she said. “If this is the case, future policy changes will be needed to eliminate the persistent inequities in health outcomes that we see in the United States”

Reference:

Malleske DT, et al. pediatrician. 2022; doi:10.1001/jamapediatrics.2022.1457.

For more information:

Antonella Zanobetti, PhD, can be contacted at azanobet@hsph.harvard.edu.