Studies in the Clinical Evaluation of Disability in Anthracosilicosis

¹ The Barton Memorial Division of the Jefferson Medical College Hospital and the Department of Medicine of the Jefferson Medical College of Philadelphia, Pennsylvania.

The clinical features of disability in an unselected group of 375 hard coal miners with various stages of silicosis have been studied. The clinical findings in 150 cases were correlated with pulmonary function studies.

Evaluation of disability requires recognition and consideration of all factors which may contribute to the function impairment. In 49.5 per cent of cases, disability was related to one or more infectious, metabolic or degenerative medical conditions. Cardiovascular disease was seen most frequently, occurring in 18.4 per cent of cases. Active pulmonary tuberculosis was present in 12.5 per cent. Right heart strain occurred in 16.2 per cent and showed a definite relationship to the degree of emphysema.

In 50.5 per cent of cases disability was due to pulmonary function impairment per Se, related to ventilatory changes, the degree of emphysema and the respiratory gas exchange. The factors involved were multiple in most cases.

A fair estimate of the degree of function impairment can be obtained by the ordinary clinical methods when the major factors in the impairment are related to decreased ventilation and increased emphysema. Clinical examination will not reveal impairment due to arterial blood oxygen unsaturation.

In a significant number of cases the degree of function impairment was not proportional either to the amount of silicosis or to the length of exposure.