Malnutrition is associated with mortality in Sjögren's syndrome-associated interstitial lung disease

The role of nutritional status as a prognostic factor in patients with Sjögren's syndrome-associated interstitial lung disease (SjS-ILD) is currently unclear. This study aimed to predict the prognosis of patients with SjS-ILD through their nutritional status assessment. In this retrospective observational study, nutritional status was evaluated at the time of diagnosis using body mass index (BMI) and nutritional markers such as controlling nutritional status (CONUT), the Glasgow prognostic score (GPS), and prognostic nutrition index (PNI) for all participants. Receiver operating characteristic (ROC) analyses were performed using BMI and each nutritional marker data to compare the area under the ROC curve (AUC) and find the cutoff value using the maximum Youden index. Kaplan-Meier analysis and Cox proportional hazards regression analysis were performed to predict the prognosis of SjS-ILD patients. A total of 112 SjS-ILD patients were enrolled in the study, and 8.9% died during the follow-up period. The median time from diagnosis to follow-up period was 4.2 years. The AUC for PNI was the highest among nutritional markers and BMI, and PNI cutoff value was used to distinguish between the PNI < 47.7 and PNI ≥ 47.7 groups. A statistical difference was observed in the Kaplan-Meier analysis and log-rank test (p = 0.005). In multivariable analyses, PNI < 47.7 (hazard ratio 9.40, 95% confidence interval 1.54-57.21) is associated with increased mortality, suggesting the importance of early nutritional intervention for malnutrition in SjS-ILD patients.