Bronchitis in agricultural workers

Three groups of agricultural workers, which include grain workers, farmers, and animal confinement workers have been studied extensively in order to understand better the respiratory complaints seen in these populations. It appears that chronic bronchitis is more common in all of these groups than it is in the general population. Symptoms that suggest the presence of acute bronchitis are also common in these workers and are seen more often in smokers than in nonsmokers. Areas in need of further study include the potential relationship between repeated episodes of acute respiratory symptoms following grain dust inhalation and the risk for developing chronic bronchitis. Some studies suggest that the effects of smoking are additive with those of the organic dust exposure in the causation of chronic bronchitis, emphasizing the need for smoking cessation in these groups. Respiratory protective devices, although not conclusively demonstrated to be useful in the prevention of bronchitis in agricultural workers, likely have an important role in protecting workers from organic dust. Pharmacologic agents have yet to be tested in agricultural workers with chronic bronchitis or acute bronchitis symptoms. The organic dusts that agricultural workers inhale are heterogenous, complicating efforts to understand the pathophysiologic mechanisms by which they cause airways inflammation. However, work with grain dust extracts, with endotoxin, and other components of organic dusts may ultimately lead to the designing of pharmacologic therapies for bronchitis in agricultural workers.