RT Journal Article
SR Electronic
T1 Vehicle exhaust levels outside home and exhaled NO - Results from the Swedish GA2LEN study
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P1045
VO 40
IS Suppl 56
A1 Bertil Forsberg
A1 David Olsson
A1 Anders Bjerg
A1 Alexandra Ek
A1 Linda Ekerljung
A1 Andrei Malinovschi
A1 Roelinde Middelveld
A1 Christer Janson
YR 2012
UL http://erj.ersjournals.com/content/40/Suppl_56/P1045.abstract
AB Fraction of NO in exhaled air (FeNO) is a common method to assess airway inflammation. FeNO has been used to study effects of air pollution, especially short-term exposure. Our aim was to study if living in areas with high levels of vehicle exhaust results in chronically increased levels of FeNO.We study subjects with asthma (n=473), sinusitis (n=109), asthma and sinusitis (n=130), symptoms suggestive of asthma (n=383), and a random control group (n=222), aged 17-76 years (median 45 years) from the Swedish GA2LEN Study.Exhaust exposure at the home address was modelled as the annual mean concentration of nitrogen oxides (NOx) in 50 m grids from a dispersion model using traffic counts and emission factors (NOx/km). We used log-transformed FeNO (50mL/s) from the clinical examination. The fully adjusted regression models included NOx at home, age, sex, current smoking, height and atopy, and in the combined model diagnosis category.Overall there was a very weak positive, non-significant coefficient for the effect of NOx on FeNO. For the asthma group and the group with some asthma-like symptom, this increase was 4% per 10 µg/m3 increase in NOx. The geometric mean FeNO levels were 19.3 for the asthmatics and 15.7 for the control group. Subjects with chronic high pollution exposure in terms of tobacco smoke had reduced FeNO also in our study.In conclusion, we see no significant association between modelled annual level of vehicle exhaust outside home and FeNO in any of the studied groups. A few other studies have observed such an association. We have not yet adjusted for a possible short-term effect of air pollution levels on FeNO.