Association between Sjogren's Syndrome and Respiratory Failure: Put Airway, Interstitia, and Vessels Close Together: A National Cohort Study

Objectives: Few studies have evaluated the association between Sjogren's syndrome (SS) and respiratory failure (RF). Thus, we conducted a retrospective national cohort study to investigate whether Sjogren's syndrome (SS) increases the risk of respiratory failure (RF). Methods: The cohort consisted of 4954 newly diagnosed patients with SS but without a previous diagnosis of RF, and 19816 patients as the comparison cohort from the catastrophic illnesses registry, obtained from the 2000-2005 period. All of the study participants were followed from the index date to December 31, 2011. We analyzed the association between the risk of RF and SS by using a Cox proportional hazards regression model, controlling for sex, age, and comorbidities. Results: The overall incidence rate of RF showed a 3.21-fold increase in the SS cohort compared with the comparison cohort. The adjusted HR of RF was 3.04 for the SS cohort compared with the comparison cohort, after we adjusted for sex, age, and comorbidities. The HRs of RF for patients with primary SS and secondary SS compared with the comparison cohort were 2.99 and 3.93, respectively (P for trend,. 001). The HRs of RF increased as the severity of SS increased, from 2.34 for those with no inpatient care experience to 5.15 for those with inpatient care experience (P for trend, <.001). Conclusion: This study indicates that clinical physicians should not only consider secondary SS but also primary SS as a critical factor that increases the risk of RF.