부산대학교 도서관

Introduction and objectivesThere is evidence that exposure to traffic-related air pollution may impact adversely on asthma and other respiratory conditions. We aimed to test the hypothesis that day-to-day variability in personal air pollution exposure has clinically important effects on asthma symptoms, lung function and airway inflammation.MethodsWe recruited 31 patients with a clinical diagnosis of asthma from Leicester and the surrounding area. Participants were provided with a personal air pollution monitor (Cairclip NO2/O3; Cairpol, La Roche Blanche, France) which measures total oxidants in the ambient air and stores 15 min average readings. The Cairclip was attached to a belt or handbag when outdoors, and kept in close proximity to participants when indoors. We also measured exposure using modelled daily average ambient levels of NO2and particulate matter (PM2.5and PM10) based upon satellite imaging data, as well as directly measured ozone, NO2and PM2.5levels from a monitoring station in central Leicester.Participants were provided with an electronic symptom diary and peak expiratory flow metre (Micro Diary; Carefusion, Basingstoke, UK) and a portable exhaled nitric oxide monitor (NOBreath; Bedfont, Maidstone, UK), and made daily measurements using these for 12 weeks. Relationships between exposure and outcome variables were analysed using cross-correlation.ResultsAt a group level there were no consistent relationships between personal air pollution exposure and clinical outcomes. However, a number of individuals (n=6) manifested strong correlations between exposure and outcome variables, particularly those residing within inner-city Leicester. Figure 1 shows overlaid time series of modelled ambient NO2levels and exhaled nitric oxide measurements in Participant 13 (Panel A). Results of the cross-correlation analysis are shown in Panel B, indicating a strong positive correlation centred on a lag of zero days.[Figure]ConclusionsAir pollution exposure appears to have a significant effect on symptoms, lung function and airway inflammation in selected patients with asthma. These individuals may have a combination of increased susceptibility and higher than average levels of exposure. Future studies should focus on understanding the genetic and epigenetic mechanisms underlying susceptibility to air pollution, as well as developing strategies to mitigate the effects of exposure in susceptible individuals.