June 9, 2017
A recent study has associated air pollution exposure to ambient particulate matter – that is, small solid and liquid particles like those found in smoke and smog – with increases in the length of the QT interval on electrocardiograms, which is a known risk factor for sudden cardiac death.
This evidence supports previous findings that established the connection between air pollution exposure, especially exposure to particulate matter, and the increased burden of cardiovascular diseases both in the United States and globally.
Rahul Gondalia, MPH, a doctoral student of epidemiology in the UNC Gillings School of Global Public Health, is lead author of the new study. His findings suggest that some individuals may have an inherent genetic susceptibility to experiencing longer QT intervals upon exposure to elevated levels of particulate matter in the air.
The full article, titled “Genome-wide Association Study of Susceptibility to Particulate Matter-Associated QT Prolongation,” was published online June 8 by Environmental Health Perspectives.
Gondalia and co-authors studied 22,158 participants from the Atherosclerosis Risk in Communities Study and the Women’s Health Initiative clinical trials, all of whom underwent electrocardiograms and provided genomic data during the period between 1986 and 2004. Participants included African-American, Hispanic/Latino, and white men and women in the United States.
After analyzing these data, the investigators found evidence that a common genetic variation may make some people more vulnerable to experiencing longer QT intervals when they are exposed to high levels of particulate matter.
In the United States, the Clean Air Act mandates the setting of National Ambient Air Quality Standards for particulate matter in order to protect residents from ambient air pollution exposure.
“Some individuals are more sensitive to the effects of air pollution, such as young children with developing lungs or older adults with diabetes,” Gondalia explained. “According to our findings, some people also may be innately, or genetically, susceptible to air pollution, and may experience negative effects at pollution levels far below the current accepted standards.”
If this finding is corroborated, it may warrant more stringent air quality standards than those now mandated by the Clean Air Act.
“Because everyone breathes air, air pollution regulation can benefit large groups of people,” said Gondalia. “By implementing more stringent standards, we could see a reduction in population exposure to air pollution that directly translates to a reduction in the burden of related diseases.”
Other study co-authors associated with the Gillings School include Christy L. Avery, PhD, assistant professor, Melanie D. Napier, PhD, recent alumna, Raúl Méndez-Giráldez, PhD, postdoctoral fellow, James D. Stewart, MS, senior spatial analyst, Kari E. North, PhD, professor, and Eric A. Whitsel, MD, research associate professor, all with the Department of Epidemiology, and Yun Li, PhD, associate professor with the Department of Biostatistics.