Pulmonary Abnormalities In Newly Diagnosed Rheumatoid Arthritis

Background: Pulmonary disease is a major cause of excess mortality among patients with rheumatoid arthritis (RA), but the benefit of screening for pulmonary disease in RA is unknown. The aim of this study was to evaluate pulmonary function and CT imaging in patients with early RA. Method: Patients with newly diagnosed RA were recruited prospectively at a single center. They underwent pulmonary function testing and coronary CT angiography at inclusion, and the pulmonary CT images were used in the respiratory assessment. Results: One-hundred and fifty patients were included in the study, and 127 had a pulmonary function test within six months after the RA diagnosis. Mean age was 57 years, 62% were female, and 54% were current or former smokers with an average of 24 packyears. Mean FEV1 was 99% predicted and FVC 106% predicted. Twenty-eight patients (22%) had obstructive spirometry patterns, 24 of those were smokers. Mean total lung capacity was 105%, residual volume (RV) 119% and diffusion capacity for carbon monoxide (DLco) 84%. CT scans were performed in 136 patients. The most common findings were pulmonary nodules (18 pts), emphysema (13 pts), and bronchiectasis (5pts). Two patients had manifest interstitial lung disease (one UIP and one NSIP), and four patients had interstitial lung abnormalities. Thirteen patients had other minor CT findings, and 82 patients (60%) had no pulmonary CT abnormalities. Signs of emphysema with hyperinflation and diffusion impairment (RV>120% and DLco<80%) was significantly associated with smoking (p=0.013) and so was DLco < 80% (p=0.005) and emphysema on CT (p=0.044). Conclusion: Smoking rates were high, and smoking was significantly associated with signs of emphysema in patients with early RA.