Pulmonary functions testing in patients with rheumatoid arthritis

Background: A high incidence of abnormal pulmonary function tests has been reported in cross-sectional studies among patients with rheumatoid arthritis. Few patients have been enrolled in longitudinal studies. Objectives: To perform PFT in rheumatoid arthritic patients without pulmonary involvement and to identify variables related to changes in PFT over 5 years of follow-up. methods: Consecutive RA patients underwent PFT according to recommendations of the American Thoracic Society. All surviving patients were advised to repeat the examination 5 years later. results: PFT was performed in 82 patients (21 men, 61(women). Their mean age was 55.7 (15.9) years and the mean RA duration was 11.1 (10) years. Five years later 15patients (18.3%) had died. Among the 67 surviving patients,38 (56.7%) agreed to participate in a follow-up study. The initial PFT revealed normal PFT in only 30 patients (36.6%);an obstructive ventilatory defect in 2 (2.4%), a small airway defect in 12 (17%), a restrictive ventilatory defection 21 (25.6%), and reduced DLco in 17 (20.7%). Among the38 patients participating in the 5 year follow-up study, 8developed respiratory symptoms, one patient had a new obstructive ventilatory defect, one patient developed are strictive ventilatory defect, and 5 patients had a newly developed small airway defect. The DLco had improved in7 of the 8 patients who initially had reduced DLco, reaching normal values in 5 patients. Over the study period a newreduction in DLco was observed in 7 patients. Line arregression analyses failed to identify any patient or disease-specific characteristics that could predict a worsening in PFT. The absolute yearly decline in forced expiratory volume in 1sec among our RA patients was 47 ml/year, a decline similar to that seen among current smokers. conclusions: Serial PFT among patients with RA is in dicated and allows for earlier identification of various ventilatory defects. Small airways disturbance was a common finding in our RA patients.