Pulmonary disability in former Appalachian coal miners.

A prospective case-control study was undertaken to assess respiratory disability in 133 former coal miners who were claimants for "black lung" benefits. Consecutive assignment was made to either case or control group based on their chest radiograph having shown coal workers' pneumoconiosis or no coal workers' pneumoconiosis. A respiratory occupational survey was completed with physical examination that placed special emphasis on the cardiorespiratory systems. Subjects underwent pulmonary function testing while 92 of these also received arterial blood gases to assess respiratory disability and pulmonary insufficiency. Arterial blood gases were superior to spirometry in assessment of pulmonary insufficiency/disability. Smoking interacts with coal workers' pneumoconiosis to cause pulmonary insufficiency. The most frequent spirometric pattern was obstructive. Disability was caused by occupational injuries and comorbidities, both of which occurred with greater frequency in miners with coal workers' pneumoconiosis than in controls. Pulmonary insufficiency appears to be a better discriminator than respiratory disability in coal miners, suggesting that arterial blood gases replace spirometry in their evaluation. Greater emphasis on smoking intervention among coal miners should be given.