Journal Article

Reducing Personal Exposure to Particulate Air Pollution Improves Cardiovascular Health in Patients with Coronary Heart Disease

Lee, Matthew M.Y., Barnes, Gareth D., Boon, Nicholas A., Mills, Nicholas L., Langrish, Jeremy P., Li, Liming, Wang, Shengfeng, Newby, David E., Li, Jing, Li, Xi, Cassee, Flemming R., Miller, Mark R., Jiang, Lixin, Donaldson, Ken

2012

Overview

Air pollution exposure increases cardiovascular morbidity and mortality and is a major global public health concern. We investigated the benefits of reducing personal exposure to urban air pollution in patients with coronary heart disease. In an open randomized crossover trial, 98 patients with coronary heart disease walked on a predefined route in central Beijing, China, under different conditions: once while using a highly efficient face mask, and once while not using the mask. Symptoms, exercise, personal air pollution exposure, blood pressure, heart rate, and 12-lead electrocardiography were monitored throughout the 24-hr study period. Ambient air pollutants were dominated by fine and ultrafine particulate matter (PM) that was present at high levels [74 μg/m³ for PM(2.5) (PM with aerodynamic diamater <2.5 µm)]. Consistent with traffic-derived sources, this PM contained organic carbon and polycyclic aromatic hydrocarbons and was highly oxidizing, generating large amounts of free radicals. The face mask was well tolerated, and its use was associated with decreased self-reported symptoms and reduced maximal ST segment depression (-142 vs. -156 μV, p = 0.046) over the 24-hr period. When the face mask was used during the prescribed walk, mean arterial pressure was lower (93 ± 10 vs. 96 ± 10 mmHg, p = 0.025) and heart rate variability increased (high-frequency power: 54 vs. 40 msec², p = 0.005; high-frequency normalized power: 23.5 vs. 20.5 msec, p = 0.001; root mean square successive differences: 16.7 vs. 14.8 msec, p = 0.007). However, mask use did not appear to influence heart rate or energy expenditure. Reducing personal exposure to air pollution using a highly efficient face mask appeared to reduce symptoms and improve a range of cardiovascular health measures in patients with coronary heart disease. Such interventions to reduce personal exposure to PM air pollution have the potential to reduce the incidence of cardiovascular events in this highly susceptible population.

• Publisher: US Department of Health and Human Services,National Institute of Environmental Health Sciences
• Subject: Aged / Air / Air pollution / Arrhythmias, Cardiac - chemically induced / Arrhythmias, Cardiac - epidemiology / Arrhythmias, Cardiac - prevention & control / Biological and medical sciences / Blood Pressure / Blood Pressure Monitoring, Ambulatory / Carbon / Cardiac dysrhythmias / Cardiology. Vascular system / Cardiovascular diseases / China - epidemiology / Coronary Disease - chemically induced / Coronary Disease - epidemiology / Coronary Disease - prevention & control / Coronary heart disease / Cross-Over Studies / Electrocardiography, Ambulatory / Environment. Living conditions / Environmental pollutants toxicology / Exposure / Female / Free radicals / Health / Heart / Heart diseases / Heart Rate / Humans / Incidence / Inhalation Exposure - prevention & control / Male / Masks / Medical sciences / Middle Aged / Myocardial Ischemia - chemically induced / Myocardial Ischemia - epidemiology / Myocardial Ischemia - prevention & control / Organic carbon / Particulate matter / Particulate Matter - analysis / Particulate Matter - toxicity / Patients / Polycyclic aromatic hydrocarbons / Prospective Studies / Protective equipment / Public health / Public health. Hygiene / Public health. Hygiene-occupational medicine / Toxicology / Urban Health