Incidence, prevalence and mortality of rheumatoid arthritis-associated interstitial lung disease : a retrospective study

Abstract

<b>Introduction and background:</b> Pulmonary fibrosis (PF) is the most common pulmonary manifestation of rheumatoid arthritis (RA) but is currently largely under-diagnosed. This leads to a late onset of management, resulting in significant morbidity and mortality. <b>Aims and objectives:</b> The aim of our study is to describe the prevalence and incidence of pulmonary manifestations and especially PF among all RA patients referred to our center. We seek to compare their epidemiological characteristics, pulmonary comorbidities and survival rates. <b>Methods:</b> We conducted a retrospective study based on data extracted from our center’s computerized files and completed by a file review. <b>Results:</b> Among 1512 patients with RA, we found out that 197 had a pulmonary manifestation (based on CT scans and pulmonary function testing). In those 197 patients, 29,9% were presenting non-specific interstitial pneumonia (NSIP) pattern and 14,2% were presenting usual interstitial pneumonia (UIP) pattern. In this subgroup, 57 had progressive fibrosing interstitial lung disease (PF-ILD) (45,6% NSIP and 26,3% UIP). The overall ratio of patients suffering from the PF-ILD phenotype in the total RA population was 3,8 % whereas 28,9 % of patients suffering from RA associated lung diseases were presenting the PF-ILD phenotype. <b>Conclusions:</b> RA associated lung disease is associated with a high morbid-mortality rate and is today the major cause of death in those patients. Since anti-fibrotic therapies have shown to be effective in patients with a PF-ILD phenotype there is a clear specific need of identifying those patients at risk of progressive lung decline.