Prevalence and impact of Sjögren's syndrome in primary biliary cholangitis: a systematic review and meta-analysis

Abstract

Introduction and objectives: We performed a systematic review and meta-analysis to evaluate the prevalence of concomitant Sjögren's syndrome (SS) with primary biliary cholangitis (PBC) in adults and quantify the impact of SS on PBC.

Methods: PubMed, Web of Science and Cochrane library were searched using subject terms and predefined inclusion and exclusion criteria.

Results: Seventeen articles were included. The prevalence of SS in PBC patients ranged from 3.5 to 73% (35% pooled) (95% CI: 28-41%; p < 0.01). Seven studies included various biochemical indicators, including alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), γ-glutamyltransferase (γ-GT), total bilirubin (TBiL), albumin (ALB) and platelet (PLT), and immunological indexes including IgG, IgM, antinuclear antibody (ANA), anti-mitochondrial antibody (AMA), AMA-M2 and anti-Ro/Sjögren's syndrome antigen A (SSA) antibodies. Meta-analysis showed that there were no significant differences in ALT, AST, ALP, γ-GT, TBiL and IgM levels between PBS and PBC with SS. Pooled analysis showed that ALB (MD=0.82; 95% CI: 0.08-1.56) and PLT (MD=30.41; 95% CI: 10.16-50.66) levels were lower, IgG levels (MD=-1.55; 95% CI: -2.39 to -0.72) were higher, and the positive ratios of ANA (RR=0.92; 95% CI: 0.87-0.98), AMA (RR=0.94; 95% CI: 0.89-0.98), AMA-M2 (RR=0.77; 95% CI: 0.70-0.85) and anti-Ro/SSA antibodies (RR=0.29; 95% CI: 0.08-1.01) were significantly higher in PBC patients with SS than in PBC patients.

Conclusions: Our study confirms that SS is common in PBC. Comorbid SS appears to influence the clinical phenotype of PBC and may therefore influence the management of PBC.

Keywords: Autoimmune disease; Biochemical characteristics; Immunological indexes; Overlap syndrome; Prevalence.