Abstract
Background
Worsening of asthma has been found associated with traffic pollution indicators.
Aims
The aim of the study was to evaluate the impact of traffic pollution on quality of life in asthmatic subjects, individuals with CRS, and controls.
Methods
Within the Swedish GA2LEN Study, 605 asthmatics with and without CRS, 110 individuals with CRS only and 226 controls were surveyed. The mini Asthma Quality of life Questionnaire (mAQLQ), the Euro Quality of Life (EQ-5D) health questionnaire, spirometry, skin prick test, exhaled nitric oxide, smell test and peak nasal inspiratory flow were used. Air pollution levels at the home address were modeled using dispersion models.
Results
Levels of NO2 (mean 10 microg/m3) and NOx (14 microg/m3, IQR 8.7-70) were similar among groups (controls, asthmatics, individuals with CRS, and asthmatics with CRS). The mAQLQ overall score was not found associated with NO2 or NOx, with or without adjustments, and neither was scores within each of the four domains of mAQLQ: symptoms, activity limitations, emotional functions, and effects of environmental stimuli. The mean EQ-5D index value, based on the five dimensions mobility, self-care, usual activities, pain/discomfort and anxiety depression, was also found unrelated to NO2 and NOx. Stratification by condition did not reveal any differences in NO2 or NOx related effects.
Conclusions
Within these exposure levels, NO2 and NOx appear not to affect quality of life among controls, asthmatics, individuals with CRS, or asthmatics with CRS. This could perhaps be explained by selection bias related to susceptibility (avoidance), moderate exposure levels or confounders related to the type of residential area.
- © 2013 ERS