Objectives
Anti-centromere antibodies (ACA) define a subset of primary Sjögren’s syndrome (SS) with a unique phenotype, including features of limited cutaneous systemic sclerosis and a lower frequency of anti-SSA/-SSB antibodies. We sought to determine whether ACA are associated with more severe exocrine glandular dysfunction in a large cohort of primary SS subjects.
Methods
We performed a cross-sectional analysis of 1361 subjects with primary SS from the Sjögren’s International Collaborative Clinical Alliance (SICCA) registry, stratified by the presence or absence of ACA. ACA were assayed by immunofluorescence staining on HEp-2 cells.
Results
ACA were present in 82 (6%) of the 1361 SS subjects and were associated with older age, female gender, and lower frequencies of anti-SSA/-SSB, rheumatoid factor, and hyperglobulinemia. Among ACA (+) vs ACA (−) subjects, there was a higher frequency of focus score ≥2 (71 vs 53%, p=0.002), higher median focus score (2.8 vs 2.5, p=0.0440) and greater exocrine gland dysfunction: Schirmer’s test value: median 4 vs 5 mm/5 min, p=0.0003; unstimulated whole saliva (UWS) flow rate: median 0.08 vs 0.37 ml/5 min, p<0.0001. ACA (+) subjects had an increased risk of UWS<0.1 ml/min [OR=12.24 (95% CI, 4.91–41.02)] and Schirmer value <5 mm/5 min [OR=2.52 (95% CI, 1.50–4.36)] after correcting for age, gender, anti-SSA/-SSB, and focus score. Labial gland fibrosis was not different between the two groups.
Conclusions
In a large international registry of SS, ACA had an independent association with more severe exocrine glandular dysfunction. This dysfunction was associated with more pronounced labial salivary glandular inflammation but not fibrosis.