The pulmonary vasculature are the first blood vessels to encounter polluted air that is breathed in, and a dual-action study is now pointing out the negative effect pollutants have on pulmonary function and the resulting risk posed to cardiovascular function.
More than 16,000 participants joined the population-based part of the new study, led by cardiologist Dr. Jean-Francois Argacha, which was the first human study to make clear connections between air pollution and pulmonary vascular function. Air pollutants exist in the form of both particles and gases, and the result from the population study showed that specific particles and specific gases, such as ozone, are particularly associated with a negative effect on pulmonary vascular function.
The population study investigated common levels of outdoor air pollution, measured with echocardiography and compared to parameters conventionally used to evaluate pulmonary circulation and right ventricular function.
“Patients with obstructive sleep apnoea were at greater risk,” Argacha added.
During the individual study, ten healthy male participants were recruited to study the effect of air pollution on pulmonary circulation in more detail. Each participant was exposed to pollutants in a chamber, either ambient air or dilute diesel exhaust for two hours. In addition to echocardiography, researchers conducted a cardiac stress test to measure and compare effects.
The results showed that exposure to diesel exhaust was only more harmful than ambient air during the cardiac stress test. “This suggests that pollution is more harmful to the lung circulation during exercise," Argacha said.
The study’s dual findings suggest that clean air is just as important for pulmonary vascular function as a factor of cardiovascular disease as are other factors like cholesterol, diet, and exercise. "Our dual approach provides original data on the impact of air pollution on the pulmonary circulation,” Argacha said. ‘The individual study strengthens the plausible link emerging from the epidemiological research."
Impaired pulmonary vascular function can lead to heart disease as the blood vessels narrow and the heart doesn’t receive as much oxygen as it needs. "This is a major public health issue for people living in polluted urban areas where exercise could damage the lungs and potentially lead to decompensated heart failure,” Argacha said.
Based on the findings from Argacha’s study, researchers suggest that individuals limit their physical activity during heavy air pollution, although the duration and intensity of exercise to avoid is yet to be defined. Emission control via particulate filters helps to prevent air pollution in the first place, but much more is needed to truly bring air back to a cleaner state.
Source: European Society of Cardiology