Long-term air pollution exposure is associated with increased severity of rhinitis in 2 European cohorts

Background: Very few studies have examined the association between long-term outdoor air pollution and rhinitis severity in adults. Objective: We sought to assess the cross-sectional association between individual long-term exposure to air pollution and severity of rhinitis. Methods: Participants with rhinitis from 2 multicenter European cohorts (Epidemiological Study on the Genetics and Environment on Asthma and the European Community Respiratory Health Survey) were included. Annual exposure to NO2, PM10, PM2.5, and PMcoarse (calculated by subtracting PM2.5 from PM10) was estimated using land-use regression models derived from the European Study of Cohorts for Air Pollution Effects project, at the participants' residential address. The score of rhinitis severity (range, 0-12), based on intensity of disturbance due to symptoms reported by questionnaire, was categorized into low (reference), mild, moderate, and high severity. Polytomous logistic regression models with a random intercept for city were used. Results: A total of 1408 adults with rhinitis (mean age, 52 years; 46% men, 81% from the European Community Respiratory Health Survey) were included. The median (1st quartile-3rd quartile) score of rhinitis severity was 4 (2-6). Higher exposure to PM10 was associated with higher rhinitis severity (adjusted odds ratio [95% CI] for a 10 μg/m3 increase in PM10: for mild: 1.20 [0.88-1.64], moderate: 1.53 [1.07-2.19], and high severity: 1.72 [1.23-2.41]). Similar results were found for PM2.5. Higher exposure to NO2 was associated with an increased severity of rhinitis, with similar adjusted odds ratios whatever the level of severity. Adjusted odds ratios were higher among participants without allergic sensitization than among those with, but interaction was found only for NO2. CONCLUSIONS: People with rhinitis who live in areas with higher levels of pollution are more likely to report more severe nasal symptoms. Further work is required to elucidate the mechanisms of this association. The following bodies funded the local studies in ECRHS III in this article: Belgium: Antwerp South, Antwerp City: Research Foundation Flanders (FWO), grant code G.0.410.08.N.10 (both sites); France: Ministère de la Santé , Programme Hospitalier de Recherche Clinique (PHRC) national 2010; Germany: Erfurt: German Research Foundation ( HE 3294/10-1 ); Spain: Fondo de Investigación Sanitaria ( PS09/02457 , PS09/00716 09/01511 , PS09/02185 , and PS09/03190 ), Servicio Andaluz de Salud, Sociedad Española de Neumología y Cirurgía Torácica ( SEPAR 1001/2010 ); Barcelona: Fondo de Investigación Sanitaria ( FIS PS09/00716 ); Galdakao: Fondo de Investigación Sanitaria ( FIS 09/01511 ); Huelva: Fondo de Investigación Sanitaria ( FIS PS09/02185 ) and Servicio Andaluz de Salud ; Oviedo: Fondo de Investigación Sanitaria ( FIS PS09/03190 ); United Kingdom: Medical Research Council (grant no. 92091 ). The Epidemiological Study on the Genetics and Environment on Asthma is funded in part by PHRC-Paris, PHRC-Grenoble, ANR 05-SEST-020-02/05-9-97, ANR-06-CEBS, ANR-CES-2009, Région Nord Pas-de-Calais, and Merck Sharp & Dohme. European Study of Cohorts for Air Pollution Effects Funding: The research leading to these results has received funding from the European Community’s Seventh Framework Program ( FP7/2007-2011 ; under grant agreement no. 211250 )