Background Rheumatoid arthritis (RA) is a chronic autoimmune condition characterised by inflammatory polyarthritis, with lung disease being an important extra-articular manifestation.
Objectives The primary aim of this study was to explore the different radiological patterns and severity of lung disease in patients with rheumatoid arthritis. A secondary aim was to determine predictors for the various patterns of lung disease.
Methods A total of 90 patients with RA and lung disease were included in this retrospective cohort study. All patients had lung disease confirmed on high resolution computed tomography (HRCT). Radiological patterns of lung disease and their severity were scored independently by an experienced chest physician and a consultant radiologist and consensus was reached.5 patterns of lung disease were characterised– fibrosis, emphysema, large airway dilatation, large airway wall thickening and mosaicism (small airways disease) and graded as absent, mild, moderate or severe.
Results 62 patients were female and 28 were male with a median age of 70 years(range 38-94 years). The mean duration of RA was 13.5 years, although 39 patients (43.3%) were diagnosed with lung disease within 1 year of diagnosis of RA. The majority of patients were receiving either oral steroids(96%) or methotrexate(88%) at the time of diagnosis of lung disease.80 patients were positive for rheumatoid factor (RF) and of the 41 patients with documented anti-citrullinated protein antibodies (ACPA),25 patients were positive. Radiological erosions were seen in 44 patients(48.9%) and extra-articular manifestations were seen in only 14 patients(15.6%). The incidence of the different lung patterns is shown in the graph. Large airway wall thickening was the commonest pattern observed(55.6%). Fibrosis emerged as the most severe radiological pattern(11.1%). Most patients had a mixed pattern of disease. There was no association between RF/ACPA positivity and the individual patterns of lung disease. DAS 28 showed a positive correlation with large airway wall dilatation at the time of diagnosis of lung disease. Female gender was identified as a predictor for mosaicism(p 0.01)and male gender as a predictor for fibrosis(p 0.03) Smoking is confirmed as a strong predictor for emphysema(p 0.002).
Conclusions In patients with RA a variety of radiological patterns of lung disease are seen. Large airway wall thickening was the commonest pattern identified in our cohort although the most severe radiological lung disease was due to fibrosis.
Disclosure of Interest None Declared