Does emotional health influence susceptibility to the physiologic effects of air pollution on adults?

Abstract

Depression has been linked to an increased susceptibility to physical illness. Our objective is to determine if emotional health modifies the effect of air pollution on pulmonary and cardiovascular physiology. This cross-sectional study was based on data collected on 5,604 subjects between 2007 and 2009 during the Canadian Health Measures Survey. Subjects were assigned the air pollution values obtained from the National Air Pollution monitor closest to the subject's home. We tested the associations between air pollution and lung function, heart rate and blood pressure for adults whose ages were greater than 20 when the survey was conducted. Results were stratified by a self-reported happiness scale (HS). Among those who were less happy ('others'), an interquartile increase in fine particulate air pollution was associated with a 2.86% (95%CI 0.41, 5.31) increase in systolic blood pressure, a 1.70% (95% CI 0.07, 3.33) decrease in forced vital capacity (FVC), and a 1.59% (95% CI 0.09, 3.08) decrease in the FEV1/FVC ratio (ratio of percent predicted 1-second forced expiratory volume (FEV1) to FVC). Significant adverse effects were observed for six 'others' air pollution - physiology associations. In 'happy' group, none of the associations were significant. In the Canadian population, the degree of happiness may modify the vulnerability to the adverse health effects of air pollution.