Abstract
This Mendelian randomization (MR) study aimed to investigate the relationships between Sjögren syndrome (SS) and osteoporosis (OP). We selected genetic instruments for predisposition to SS on published genome-wide association studies. Using a two-sample MR approach, we assessed association SS and OP. The random effects inverse variance weighting method was used as the primary analysis method, and the weighted median method, MR-Egger, weighted mode, and simple mode were used as supplementary analytical methods. Sensitivity analysis was performed using the heterogeneity test, the pleiotropy test, and the leave-one-out test. SS was notably associated with the presence of OP (odds ratio: 1.191; 95% confidence interval: 1.084-1.309; P < .005), but OP was not a susceptible factor for SS. This study suggested that from a genetic point of view, the SS was indeed a risk factor for OP. Furthermore, no significant causal effect of OP on SS was observed, indicating the absence of reverse causality between SS and OP.