Abstract: Objective To investigate the clinical features, imaging scores, and prognosis of secondary interstitial lung disease (ILD) in patients with overlapping rheumatoid arthritis and Sjögren’s syndrome (RA-pSS). Methods Clinical data and high-resolution lung CT (HRCT) data of 43 cases of RA-pSS patients were retrospectively collected including 15 cases of RA-pSS associated ILD and 28 cases of RA-pSS with non-ILD. There were no significant differences in age, gender and course of disease between the two groups. The clinical data, lung function, imaging changes in patients with RA-pSS, and score of the lung HRCT were observed, imaging characteristics and prognosis of RA-pSS associated ILD were analyzed. Results Compared with RA-pSS without secondary ILD group, patients with RA-pSS secondary to ILD showed significantly higher levels of C reactive protein (CRP, P＜0.05). RA-pSS secondary to ILD group showed the most common manifestation of interlobular septal thickening in high-resolution CT (HRCT). The most common type of ILD was nonspecific interstitial pneumonia (NSIP) in the RA-pSS secondary ILD group. Compared with the non-UIP group, the clinicalradiology-physiology score (CRP score) was significantly higher in the UIP group (P＜0.05). Compared with the RA-pSS without the secondary ILD group, the survival rate was significantly lower in the RA-pSS secondary ILD group (P＜0.01).Conclusion Patients with RA-pSS associated ILD have higher CRP for their inflammatory markers, complicated imaging characteristic and poor prognosis, and should receive clinical attention.

Key words: arthritis, rheumatoid, Sjogren's syndrome, lung diseases, interstitial, overlap syndrome, clinical-radiology;physiology score