Abstract
OBJECTIVE: Laboratory diagnostic markers and clinical presentations of Sjögren’s disease (SjD) may vary by sex. This study aimed to investigate the association between lnc-DC expression and female SjD and to evaluate its potential as a diagnostic biomarker in female SjD patients. METHODS: 599 SjD patients were retrospectively analyzed in this cohort, additionally 337 healthy adults without autoimmune diseases served as the healthy control group (HC). Adjusted p - values are reported for all exploratory analyses. Associations between diverse clinical parameters and SjD occurrence among female SjD patients were assessed using Cox proportional hazards models. To account for multiple hypothesis testing across 40 comparisons, we applied the Benjamini-Hochberg false discovery rate (FDR) correction with q = 0.05. Subsequently, receiver operating characteristic (ROC) curves were constructed to evaluate the diagnostic performance of lnc-DC expression levels in distinguishing female SjD patients. RESULTS: After a retrospective observation for median 44 months (Interquartile Range (IQR): 35–55 months), symptoms such as dry mouth, joint pain, reduced tear flow, elevated IgM concentrations, increased ESSDAI scores, and higher detection rates of rheumatoid factor (RF), anti-Ro52 antibody, and anti-SSA antibody were significantly more prevalent among female patients (all p < 0.05). Moreover, female participants exhibited substantially increased levels of lnc-DC expression (p < 0.001). In contrast, males displayed a higher prevalence of parotid gland enlargement and interstitial lung disease (ILD) (both p < 0.001). Cox proportional hazards models identified elevated lnc-DC expression as an independent predictor for SjD development in females (p < 0.001). After FDR correction, elevated lnc-DC remained significantly associated with SjD status (adjusted p < 0.001). Other biomarkers did not survive correction (adjusted p > 0.05). Additionally, ROC curve analysis demonstrated that elevated lnc-DC levels effectively distinguished female SjD patients, with an area under the curve (AUC) of 0.83, sensitivity of 78.64%, and specificity of 73.61%, p < 0.001. CONCLUSIONS: Female SjD patients exhibited significantly elevated lnc-DC expression. When integrated with conventional serological markers, lnc-DC enhanced SjD diagnostic accuracy. These findings suggest lnc-DC as a sex-specific adjunct biomarker for SjD clinical diagnosis.