Insights into Patient Heterogeneity in Sjögren's Disease.

Sjögren's disease is multi-system autoimmune disease characterized by dryness of mucosal surfaces, fatigue, and pain. Heterogeneity among patients is a major obstacle for timely diagnosis, management of patients, and clinical trial design. Strategies for patient stratification are therefore desperately needed. In this review, we aimed to summarize current stratification approaches. Two major approaches for patient stratification are currently used. The first one is based on patient-reported symptoms and the subsequent analysis of the clinical and biological characteristics defining the identified clusters. The second strategy is based on the molecular stratification of patients, followed by the analysis of clinical characteristics along with other biological data. The combination of different approaches holds great potential to improve the recognition of patient subgroups and the development of tailored therapies. The current literature suggests that three to four subgroups of patients with SjD exist. Whether these subgroups represent disease stages or disease endotypes is still a matter of debate and will be a topic of future research.