Exposure of chronic obstructive pulmonary disease patients to particles: Respiratory and cardiovascular health effects

Abstract

To examine hypotheses regarding air pollution health effects, we conducted an exploratory study to evaluate relationships between personal and ambient concentrations of particles with measures of cardiopulmonary health in a sample of patients with chronic obstructive pulmonary disease (COPD). Sixteen currently non-smoking COPD patients (mean age=74) residing in Vancouver were equipped with a particle (PM_2.5) monitor for seven 24-h periods. Subjects underwent ambulatory heart monitoring, had their lung function and blood pressure (BP) measured, and recorded symptoms and medication use. Ambient PM_2.5, PM₁₀, sulfate, and gaseous pollutant concentrations were monitored at five sites within the study area. Although no associations between air pollution and lung function were statistically significant, an estimated effect of 3% and 1% declines in daily FEV₁ change (ΔFEV₁) for each 10 μg/m³ increase in ambient PM₁₀ and PM_2.5, respectively, was observed. Increases of 1 μg/m³ in personal or ambient sulfate were associated with 1.0% and 0.3% declines in ΔFEV₁, respectively. Weak associations were observed between particle concentrations and increased supraventricular ectopic heartbeats and with decreased systolic BP. No consistent associations were observed between any particle metric and diastolic BP, heart rate, or heart rate variability (r-MSSD or SDNN), symptom severity, or bronchodilator use. Of the pollutants measured, ambient PM₁₀ was most consistently associated with health parameters; the use of personal exposures did not improve the strength of any associations or lead to increased effect estimates.