Decline in air pollution and change in prevalence in respiratory symptoms and chronic obstructive pulmonary disease in elderly women.
BACKGROUND
While adverse effects of exposure to air pollutants on respiratory health are well studied, little is known about the effect of a reduction in air pollutants on chronic respiratory symptoms and diseases. We investigated whether different declines in air pollution levels in industrialised and rural areas in Germany were associated with changes in respiratory health over a period of about 20 years.


METHODS
We used data from the SALIA cohort study in Germany (Study on the influence of Air pollution on Lung function, Inflammation and Aging) to assess the association between the prevalence of chronic obstructive pulmonary disease (COPD) and chronic respiratory symptoms and the decline in air pollution exposure. In 1985-1994, 4874 women aged 55-years took part in the baseline investigation. Of these, 2116 participated in a questionnaire follow-up in 2006 and in a subgroup of 402 women lung function was tested in 2008-2009. Generalized estimating equation (GEE) models were used to estimate the effect of a reduction in air pollution on respiratory symptoms and diseases.


RESULTS
Ambient air concentrations of particulate matter with aerodynamic size < 10 microm (PM10) declined in average by 20 microg/m3. Prevalence of chronic cough with phlegm production and mild COPD at baseline investigation compared to follow-up was 9.5% vs. 13.3% and 8.6% vs. 18.2%, respectively. A steeper decline of PM10 was observed in the industrialized areas in comparison to the rural area, this was associated with a weaker increase in prevalence of respiratory symptoms and COPD. Among women who never smoked, the prevalence of chronic cough with phlegm and mild COPD was estimated at 21.4% and 39.5%, respectively, if no air pollution reduction was assumed, and at 13.3% and 17.5%, respectively, if air pollution reduction was assumed.


CONCLUSIONS
We concluded that parallel to the decline of ambient air pollution over the last 20 years in the Ruhr area the age-related increase in chronic respiratory diseases and symptoms appears to attenuate in the population of elderly women.
Schikowski
Tamara
T
Department of Epidemiology, Institut für Umweltmedizinische Forschung (IUF) at the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany. tamara.schikowski@unibas.ch
Ranft
Ulrich
U
Sugiri
Dorothee
D
Vierkötter
Andrea
A
Brüning
Thomas
T
Harth
Volker
V
Krämer
Ursula
U
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000397:Air Pollution / Q000009:adverse effects*; D015331:Cohort Studies; D004781:Environmental Exposure / Q000009:adverse effects; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D052638:Particulate Matter / Q000009:adverse effects*; D015995:Prevalence; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology* / Q000503:physiopathology; D012129:Respiratory Function Tests / Q000639:trends; D012307:Risk Factors
D052638:Particulate Matter