Pollution in at-risk communities linked to congenital heart disease in newborns
Social deprivation and environmental pollutant exposure are potential risk factors for live-born congenital heart disease in California, indicating that harmful toxins may be prevalent in at-risk communities, researchers reported.
Maternal comorbidities accounted for a small proportion of this relationship, but not all.
According to research published in the Journal of the American Heart Association, investigators utilized U.S. census data in addition to an environmental exposure index that included data from the California Communities Environmental Health Screening Tool to assess possible risk factors for live-born incidence of congenital heart disease. Individuals were stratified into four quartiles, with quartile 1 being the best and quartile 4 the worst.
After adjustment for maternal race, ethnicity and age, researchers observed that the OR for live-born congenital heart disease was 1.31 times greater among individuals in quartile 4 of social deprivation (95% CI, 1.21-1.41) compared with those in quartile 1.
The OR for live-born congenital heart disease was 1.23 in individuals in quartile 4 for exposure to environmental pollutants (95% CI, 1.15-1.31) compared with those in quartile 1.
More common characteristics among infants with congenital heart disease vs. without included prematurity (19.1% vs. 8.7%; P < .001), small for gestational age (16.6% vs. 8.1%; P < .001) and chromosomal abnormalities (20.1% vs. 0.25%; P < .001).
Through causal mediation analysis, researchers determined that one or more maternal comorbidities accounted for only 13% (95% CI, 10-20) of the relationship. The most significant factors that affected infants with congenital heart disease included prepregnancy BMI of at least 25 kg/m2 (45.1% vs. 42.7%; P < .001), preexisting diabetes (3.2% vs. 0.8%; P < .001), preexisting hypertension (1.7% vs. 1.1%; P < .001) and preeclampsia (5.6% vs. 3.8%; P < .001).
“In this large population-based sample from the state of California, we demonstrate the influence of socioeconomic factors and exposures to environmental pollutants on the incidence of live-born, clinically significant congenital heart disease,” Shabnam Peyvandi, MD, MAS, associate professor of pediatrics at the University of California, San Francisco, and colleagues wrote. “In particular, increasing exposure to social deprivation and environmental pollutants was associated with an increased live-born incidence of congenital heart disease in offspring. Some, but not all, of this association is explained by maternal comorbidities, suggesting other potential pathways for the role of the maternal environment in the formation of congenital heart disease in offspring.”
For this study, researchers included live-born infants with gestational ages 22 to 42 completed weeks with valid census tract information (n = 2,419,651; 7,698 with congenital heart disease). Forms of environmental exposures included in this analysis were toxic release from facilities, air quality measured by ozone, fine particulate matter, drinking water contaminants and pollution from diesel engines or exhaust.
“Our findings further strengthen the notion that environmental injustice exists and that social policy initiatives to decrease the burden of congenital heart disease should focus on minimizing exposures to harmful toxins in socioeconomically deprived regions,” the researchers wrote. “In addition to large organizations attempting to modify environmental policies to minimize these social disparities, engagement with at-risk communities is key to empower those affected to influence policy change. Research is needed to determine whether community engagement and outreach to at-risk communities can allow for the identification of exposures and other risk factors and the development of feasible and cost-effective interventions to lessen health disparities.” – by Scott Buzby
Disclosures: The authors report no relevant financial disclosures.