Lung function of farmers in England and Wales.

A study was performed to compare respiratory symptoms and lung function measurements in a sample of male farmers and farmworkers in different regions of England and Wales with the results obtained in a similar number of control men working in industries in the same areas. A total of 428 farmers and farmworkers drawn from 146 farms were studied. The prevalence of symptoms of chronic bronchitis assessed by the Medical Research Council questionnaire did not differ between farmers and controls. Farmers were older, taller, and heavier than controls; were less likely to smoke; and had significantly higher forced vital capacity (FVC). When each of these factors was taken into account, together with social class and geographical region, in a multiple linear regression analysis farmers were found to have significantly lower forced expiratory volume in one second (FEV1) and forced mid expiratory flow rate (FEF25-75). Among the farmers, those doing dairy farming and silage work were the only groups on their own to have significantly reduced lung function. The results of this survey suggest the need for further exploration of the mechanism of an effect of farming occupations on lung function.