Low Albumin-to-globulin Ratio is Associated with Interstitial Lung Disease in Primary Sjögren's Syndrome: a Single-Center Retrospective Cohort Study with Propensity Score Matching

To investigate the association between albumin-to-globulin ratio (AGR) and interstitial lung disease (ILD) in patients with primary Sjögren's syndrome (pSS), to identify high-risk clinical phenotypes for SS-ILD, and to construct an AGR-based nomogram risk stratification model. This was a single-center retrospective cohort study enrolling pSS patients who met the 2016 ACR/EULAR classification criteria between January 2014 and December 2024. Patients were divided into ILD and non-ILD groups based on the presence or absence of ILD. Propensity score matching (PSM) was applied to balance baseline characteristics. Univariable and multivariable logistic regression analyses were performed to evaluate the independent association between AGR and ILD. A nomogram risk stratification model was constructed based on predictors identified in the multivariable analysis, and its predictive performance was assessed using receiver operating characteristic (ROC) curve analysis. A total of 1,087 pSS patients were enrolled (93.6