Lung function in rheumatoid arthritis: a clinic survey

Abstract

Respiratory function tests were undertaken in 42 patients (25 female, 17 male) with rheumatoid arthritis in order to see whether parenchymal involvement of the lung could be detected in patients with a normal chest X ray. Significant airways obstruction was present in 10 patients (3 female, 7 male), but impaired gas transfer, as measured by the carbon monoxide method, was present in 10 female patients without any other abnormality. This latter group had no history of occupational exposure to dust, and did not differ in respiratory symptoms or clinical features from the remainder of the patients, apart from the fact that most were heavy smokers. A significant correlation between gas transfer and smoking habits was found in the group of patients as a whole, and it is concluded that while abnormal gas transfer may indicate rheumatoid involvement of the lung, smoking habits must be taken into account in the interpretation of the results.