Obstructive airway disease as a risk factor for asbestos-associated malignancy.

A case-control study of a heavily asbestos-exposed group was performed to determine if obstructive airway disorder is an independent risk factor for developing asbestos-associated malignancies. From a group of 1,500 asbestos workers who had previously undergone careful evaluation, 18 case employees were identified. Each case employee was matched by smoking status, pack-years, age, and years of asbestos exposure to a single referent, a member of the same exposed population known to be free of malignancy. The spirometry results, obtained prior to the clinical manifestation of the cancer, were compared. The FEV1/FVC ratio and the FEV1/height3 ratio were lower (P less than .05, P less than .10, respectively) in the case employees. These results suggest that obstructive airway disease may be an independent risk factor for cancer.