Natural history of coal-workers' pneumoconiosis in men over 65.

: Between 1975 and 1977, 107 Kent miners aged 65 or over who had coal-workers' pneumoconiosis (CWP) were examined for current disability. The men had worked an average of 43 years underground. Forty-nine had simple CWP, and 48 complicated (33 'A', 25 'B' and 'C' shadows). In only 34 had their CWP category increased during the last 21 years, though 62 had had their disability percentage increased (by an average of 20 per cent). Seventy-two of the 95 men tested by spirometry showed normal results for their ages. No clear relationship existed between spirometry results and category of CWP. The complicating effects of obstructive airways disease or cigarette-smoking were difficult to disentangle from those of CWP. Coal-workers' pneumoconiosis is increasingly a disease of elderly miners, and can be more benign than was previously thought. It is in these miners' interests that other (perhaps treatable) causes should be sought for any chest symptoms.