Farming and the prevalence of non-reversible airways obstruction: results from a population-based study.
BACKGROUND
Occupational exposure to noxious dusts, gases, and fumes most likely contributes to obstructive lung disease. We studied whether self-reported farming work is associated with non-reversible airways obstruction.


METHODS
Following the burden of obstructive lung disease (BOLD) study protocol, we surveyed a gender-stratified population-based sample of 2,200 adults aged 40 years and over. Pre- and post-bronchodilator spirometry, as well as information on smoking, occupation, and reported respiratory disease was recorded. According to GOLD criteria, non-reversible airways obstruction was defined as a post-bronchodilator forced expiratory volume (FEV(1))/forced vital capacity (FVC) < 0.70. Occupational and smoking history was based on questionnaire. Farming was defined as ever working in this occupation for 3 months or longer.


RESULTS
For 1,258 participants with complete data (post-bronchodilator spirometry and questionnaire data), 288 (=22.9%) reported farming. Among the 288 participants reporting farming, the prevalence of non-reversible airways obstruction was 30.2%. Farming was significantly associated with airways obstruction: chronic obstructive pulmonary disease (COPD) GOLD stage I or higher (OR 1.5; 95% CI 1.1-2.0) and COPD GOLD stage II or higher (OR 1.8; 95% CI 1.2-2.7). The latter estimate was unchanged when adjustment for competing risks gender, age, and smoking was done. In this population the risk for non-reversible airways obstruction attributable to farming was 7.7%.


CONCLUSIONS
Farming should be considered a risk factor for non-reversible airways obstruction.
Lamprecht
B
B
Department of Pneumology, Paracelsus Medical University, Salzburg, Austria. b.lamprecht@salk.at
Schirnhofer
L
L
Kaiser
B
B
Studnicka
M
M
Buist
A S
AS
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000382:Agricultural Workers' Diseases / Q000175:diagnosis / Q000453:epidemiology*; D000395:Air Pollutants, Occupational / Q000009:adverse effects*; D003430:Cross-Sectional Studies; D005260:Female; D005541:Forced Expiratory Volume; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D009922:Oregon; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology*; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology; D013147:Spirometry; D013223:Statistics as Topic; D014797:Vital Capacity
D000395:Air Pollutants, Occupational