AIRWAY-OBSTRUCTION AND RHEUMATOID-ARTHRITIS

The aim of this study was to assess the percentage of respiratory diso rders and airway obstruction in patients with rheumatoid arthritis by comparing lung function test results between patients with rheumatoid arthritis and control subjects with other rheumatological conditions. A prospective case-control study of respiratory symptoms and lung func tion abnormalities was performed in a series of 100 patients with rheu matoid arthritis., Eighty eight patients with other rheumatological di seases served as controls. Diagnosis of respiratory disorders was base d on clinical, radiological and spirometric findings. Airway obstructi on was determined from predicted values. The results were compared usi ng Student's t-test and Chi-squared tests. An explanatory analysis was carried out by linear regression. The number of symptoms, respiratory disorders (including bronchiectasis) and lung function abnormalities was higher in patients with rheumatoid arthritis than in controls. Aft er exclusion of smokers, the proportion of airway obstruction in patie nts with rheumatoid arthritis was 16% (versus 0% in controls), althoug h the patients with rheumatoid arthritis still had more symptoms and r espiratory disorders. The Chi-squared test did not identify any relati onship between airway obstruction, duration of rheumatoid arthritis an d type of treatment and occurrence of Sjogren's syndrome. In the nonsm okers, different explanatory models for the patients with and without a history of cardiac and respiratory disease emerged from multivariate analysis of indices of obstruction. These models included variables c haracterizing the severity and course of the rheumatoid arthritis. Res piratory disorders (including bronchiectasis) and airway obstruction a re more frequent among patients with rheumatoid arthritis than in rheu matological controls. Although the exact pathophysiology of the link b etween bronchial obstruction and rheumatoid arthritis is still a matte r of debate, explanatory factors for obstruction included variables ch aracterizing the rheumatoid arthritis.