Respiratory symptoms and intensity of occupational dust exposure

Objectives: Occupational exposure to dusts may result in chronic respiratory symptoms. Methods: To investigate the utility of obtaining a history of occupational exposure to dust in US veterans, a respiratory health survey was conducted between 1988 and 1992 in a community-based cohort of US veterans in southeastern Massachusetts that were eligible for Veterans' Affairs (VA) healthcare benefits but were not regular users. A mail questionnaire was used to obtain a history of cough, phlegm, and wheeze, work in a dusty job, and duration, type, and intensity of dust exposure. Information on cigarette use and other possible confounders was obtained. Results: In 2,617 white men, after the data had been adjusted for cigarette smoking, age, distance to the nearest major roadway, and chronic respiratory disease, the relative odds of chronic cough, chronic phlegm, and persistent wheeze attributable to occupational dust exposure was increased twofold. Risk also increased, based on exposure intensity. For heavy dust exposure the OR was 1.98 (95% CI 1.39-2.81) for chronic cough, 2.82 (95% Cl 2.03-3.93) for chronic phlegm, and 2.70 (95% Cl 1.95-3.75) for persistent wheeze. Conclusions: After active cigarette smoking and other possible confounders had been considered, it was found that dust exposure was related to respiratory symptoms in US veterans and that the greatest risk was attributable to heavy intensity exposure.