AIRWAYS INVOLVEMENT IN RHEUMATOID-ARTHRITIS - CLINICAL, FUNCTIONAL, AND HRCT FINDINGS

The aim of the present study was to assess the prevalence and characte ristics of airways involvement in rheumatoid arthritis (RA) patients i n the absence of interstitial lung disease. We prospectively evaluated , with high-resolution computed tomography (HRCT) and pulmonary functi on tests (PFTs), 50 patients with RA (nine males and 41 females; mean age: 57.8 yr), including 39 nonsmokers and 11 smokers (mean cigarette consumption: 15.3 pack-yr) without radiographic evidence of RA-related lung changes. PFTs demonstrated airway obstruction (i.e., reduced FEV 1/VC) in nine patients (18%) and small airways disease (SAD) (i.e., de creased FEF25-75, defined as exceeding the predicted value by 1.64 res idual SD [RSD] or more, and/or an increased phase III slope > 2 SD by single breath nitrogen washout) in four patients (8%). HRCT demonstrat ed bronchial and/or lung abnormalities in 35 cases (70%), consisting o f air trapping (n = 16; 32%), cylindral bronchiectasis (n = 15; 30%), mild heterogeneity in lung attenuation (n = 10; 20%), and/or centrilob ular areas of high attenuation (n 3; 6%). Airway obstruction and SAD w ere correlated with the presence of bronchiectasis and bronchial-wall thickening (p = 0.003), and with bronchial infection (p = 0.01), but w ere unrelated to rheumatologic data. FEF25-75 was reduced and the slop e of phase III was increased in patients with airway changes on HRCT s cans, whereas no PFT abnormalities were found in 13 of 15 patients wit h normal HRCT scans. HRCT depicted features of SAD in 20 of the 33 pat ients with normal PFTs. HRCT findings were unrelated to rheumatologic data. A high prevalence of airway abnormalities as assessed with HRCT and/or PFTs was observed in our RA population. HRCT appears to be more sensitive than PFTs for detecting small airways disease.