Ethnic differences in the prevalence of pulmonary airflow obstruction among grain workers

World Health Organization data suggest that British males over 45 have a higher death rate from chronic bronchitis, emphysema, and asthma combined than do other Europeans. Although widely supposed that this is due to particularly unfavorable environmental factors in the British Isles, as well as a higher rate of tobacco consumption, ethnicity itself may be a significant factor in determining risk of obstructive airways disease. To test this hypothesis, we have analyzed the prevalence of airflow obstruction (100 x FEV1:FVC less than 68% and FEV1 less than 84 percent predicted) in Saskatchewan grain workers of British, German, and Eastern European ancestry using the Mantel-Haenszel odds ratio (OMH) and stepwise logistic regression. We found that the British grain workers had a significantly greater prevalence of airflow obstruction (OMH = 3.2; p less than 0.01) than the Eastern Europeans. We also found that ethnic origin made a significant contribution to the estimation of risk of airflow obstruction among grain workers independent of the effects of age and smoking.