OBJECTIVE: It remains debated whether patients with primary Sjögren's syndrome (pSS) are at greater risk of mortality. We aimed to determine the magnitude of all-cause mortality risk in patients with pSS compared with the general population through a systematic review and meta-analysis. METHODS: We searched Pubmed, EMBASE and Cochrane Library for studies published from inception to October 2020. STATA meta-analysis software was used to calculate the pooled risk estimates for mortality (standardized mortality ratio, SMR). RESULTS: Our search identified 2796 articles, of which 14 studies with 14584 patients were eventually included for the analysis. A total of 902 deaths were observed. Overall, we found a 1.46-fold increased risk of death in pSS patients when compared with the general population (meta-SMR: 1.46, 95% CI 1.10-1.93). Subgroup analyses showed that mortality risks were higher in European countries (meta-SMR: 1.55, 95% CI 1.04-2.33), in retrospective studies (meta-SMR: 1.50, 95% CI 1.09-2.05), in studies based on referral cohorts (meta-SMR: 1.55, 95% CI 1.04-2.30), in studies that enrolled patients >500 (meta-SMR: 1.70, 95% CI 1.11-2.61), and in studies with follow-up time longer than 8 years (meta-SMR: 1.55, 95% CI 0.87-2.77). Significantly greater mortality risk was found in patients with older age, male gender, vasculitis, interstitial lung disease, low complements, positive anti-La/SSB and cryoglobulinemia. CONCLUSION: The existing data indicated ∼50% increase of mortality among patients with pSS compared with the general population. More attention should be paid to those patients with poor prognostic factors.
OBJECTIVE: It remains debated whether patients with primary Sjögren's syndrome (pSS) are at greater risk of mortality. We aimed to determine the magnitude of all-cause mortality risk in patients with pSS compared with the general population through a systematic review and meta-analysis. METHODS: We searched Pubmed, EMBASE and Cochrane Library for studies published from inception to October 2020. STATA meta-analysis software was used to calculate the pooled risk estimates for mortality (standardized mortality ratio, SMR). RESULTS: Our search identified 2796 articles, of which 14 studies with 14584 patients were eventually included for the analysis. A total of 902 deaths were observed. Overall, we found a 1.46-fold increased risk of death in pSS patients when compared with the general population (meta-SMR: 1.46, 95% CI 1.10-1.93). Subgroup analyses showed that mortality risks were higher in European countries (meta-SMR: 1.55, 95% CI 1.04-2.33), in retrospective studies (meta-SMR: 1.50, 95% CI 1.09-2.05), in studies based on referral cohorts (meta-SMR: 1.55, 95% CI 1.04-2.30), in studies that enrolled patients >500 (meta-SMR: 1.70, 95% CI 1.11-2.61), and in studies with follow-up time longer than 8 years (meta-SMR: 1.55, 95% CI 0.87-2.77). Significantly greater mortality risk was found in patients with older age, male gender, vasculitis, interstitial lung disease, low complements, positive anti-La/SSB and cryoglobulinemia. CONCLUSION: The existing data indicated ∼50% increase of mortality among patients with pSS compared with the general population. More attention should be paid to those patients with poor prognostic factors.