Association of ambient ozone exposure with airway inflammation and allergy in adults with asthma.
BACKGROUND
Previous studies have demonstrated associations of high ozone levels with increased epidemiologic as well as lung function measures of asthma activity.


OBJECTIVE
In an observational study during the summer months, we hypothesized that higher ambient ozone levels are associated with more frequent symptoms, higher airway and systemic inflammation, as well as worse lung function in asthmatics as compared with non-asthmatic individuals.


METHODS
Thirty-eight asthmatics and thirteen healthy control subjects residing in metropolitan Atlanta were enrolled during peak ozone season. Medical histories, quality-of-life questionnaires, spirometry, serum immunoglobulin (IgE), peripheral eosinophil counts, and exhaled nitric oxide (NO) were obtained during study visits. Personal ozone exposures over the 2 days before presentation were estimated based on location and activity surveys.


RESULTS
Upper airway symptoms were more frequent in asthmatics. Higher levels of ozone were associated with worse airflow obstruction, lower quality of life scores, greater eosinophilia, and higher exhaled NO levels in asthmatics. Finally, both asthmatics and non-asthmatics with allergies showed associations between air quality and airway inflammation.


CONCLUSIONS
In adults with asthma but not controls studied during peak ozone season, increasing ozone exposure predicted lower lung function and increased biomarkers of respiratory and systemic inflammation. These associations were enhanced in atopic participants, both with and without asthma. Importantly, the study findings were noted while atmospheric ozone levels were predominantly within the current and revised national air quality standards.
Department of Medicine, MetroHealth Medical Center, Case School of Medicine, Cleveland, Ohio 44109, USA. skhatri@metrohealth.org
Sumita B
SB
Khatri
Fernando C
FC
Holguin
P Barry
PB
Ryan
David
D
Mannino
Serpil C
SC
Erzurum
W Gerald
WG
Teague
D000328:Adult; D001249:Asthma / Q000097:blood / Q000276:immunology*; D001772:Blood Cell Count; D001944:Breath Tests; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000009:adverse effects*; D005845:Georgia; D006801:Humans; D006967:Hypersensitivity / Q000097:blood / Q000276:immunology*; D007073:Immunoglobulin E / Q000097:blood; D007249:Inflammation / Q000097:blood / Q000276:immunology; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism; D010126:Ozone / Q000276:immunology*; D012621:Seasons; D013147:Spirometry; D018709:Statistics, Nonparametric; D014505:Urban Population
D009569:Nitric Oxide; D007073:Immunoglobulin E; D010126:Ozone