Characteristics of patients with primary Sjögren's syndrome associated interstitial lung disease and relevant features of disease progression.

OBJECTIVE: To investigate characteristics of patients with primary Sjögren's syndrome (pSS)-associated interstitial lung disease (ILD) and relevant features of ILD progression.

METHOD: Patients with pSS were retrospectively reviewed, and pSS-ILD and pSS non-ILD were identified. Clinical data, laboratory parameters, pulmonary high-resolution CT (HRCT), and pulmonary function tests (PFTs) were collected. pSS-ILD patients were further categorized into subgroups according to HRCT patterns or PFTs.

RESULTS: Eighty-five pSS-ILD patients and 85 pSS non-ILD patients were included. The average age at disease onset and median disease duration were significantly higher in pSS-ILD patients than those in pSS non-ILD patients (p < 0.001). Fever, xerostomia, xerophthalmia, and numbness were more frequent, and white blood cells, C reactive protein, and immunoglobulin G (IgG) levels were higher in pSS-ILD patients when compared to pSS non-ILD patients (p < 0.01). More male patients, older age at disease onset, and less frequent anti-Ro52 antibody were noted in patients with CT-usual interstitial pneumonia (UIP) pattern. In 49 patients with pSS-ILD, who repeated PFTs 6 months from the baseline, 79.6% were stable while 20.4% progressed, with ESR and CT-UIP pattern related with disease progression.

CONCLUSIONS: Patients with pSS-ILD were characterized by more frequent fever, xerophthalmia, and elevated IgG levels, while male, older age at disease onset, and less frequent anti-Ro52 antibody were related with CT-UIP pattern. ESR and CT-UIP pattern were potential predictors for ILD progression.Key Points• pSS-ILD patients are characterized by more frequent fever, xerophthalmia and elevated IgG.• Anti-Ro52 antibody is less frequent in patients with CT-UIP pattern compared to non-UIP patterns.• ESR and CT-UIP pattern are associated with pSS-ILD progression.