Airway Involvement in a Cohort of Patients With Rheumatoid Arthritis

Abstract

PURPOSE: To asses the prevalence and characteristics of airway involvement in rheumatoid arthritis (RA) patients by high resolution computed tomography (HRCT). METHODS: We prospectively evaluated, with high resolution computed tomography (HRCT) (CT Toshiba X Press, y Picker CT Twin) and pulmonary function tests (PFTs) a cohort of 47 patients with diagnosis of RA. Scans were obtained with 1 mm thick sections at 10 mm intervals. Expiratory scans were systematically obtained at 30 mm intervals to detect areas of air trapping. RESULTS: we include 47 consecutive patients with RA (35 females and 12 males, mean age: 55 (plus or minus)13 years). The mean forced expiratory volume in the first second (FEV1) was 90% (plus or minus) 24, the mean diffusing capacity for carbon monoxide (DLCO) was 70% (plus or minus) 24. HRCT demonstrated airway involvement in 16 patients (34%) and the most prevalent features were bronchiectasis (17%), bronchiolectasis (17%), air trapping (12%) and emphysema (9%). In terms of frequency of symptoms, there were no differences between the patients with and without airway involvement. There were no differences in sex (69% females and 31% males vs 77% females and 23% males p=0,30), the prevalence of dyspnea (22 vs 47%, p = 0,882), cough (14 vs 29%, p=0,995), chronic bronchitis (0 in both groups p=1,000), smoking (25% vs 13%, p= 0,500), former smoking (38 vs 13%, p=0,302). There were no differences in the prevalence of airway obstruction defined by a decrease in the FEV1>70% in the patients who show airways involvement in the HRCT (12.5% vs 0% p= 0,258). CONCLUSION: Conclusion: the airway involvement in RA is a frequent feature in HRCT even in asymptomatic patients and no smokers. The clinical relevance is actually unclear and requires further studies. CLINICAL IMPLICATIONS: Pulmonary involvement is a frequent extraarticular manifestation in rheumatoid arthritis (RA) and includes pleural effusion, pneumothorax, interstitial lung disease, bronchiolitis, pulmonary hypertension, alteration of respiratory muscles and airway involvement like bronchiectasis. The prevalence of airway involvement could be higher as previously thought.