A study of the prevalence of sicca symptoms and secondary Sjögren's syndrome in patients with rheumatoid arthritis, and its association to disease activity and treatment profile

Aim: To examine the prevalence of sicca symptoms and secondary Sjögren's syndrome (sSS) in rheumatoid arthritis (RA) patients, and the impact of sSS on disease activity and treatment profile in RA patients. Methods: Three hundred and seven RA patients responding positive to at least one of the questions in a questionnaire about sicca symptoms, were examined by Schirmer I test for tear production, and unstimulated whole saliva collection (USWC). Secondary Sjögren's syndrome was defined by at least one subjective sicca symptom, in addition to a positive Schirmer I test and positive USWC. Results: Among the 307 RA patients, 86 (28%) responded positive to at least one question about sicca symptoms, and 11 patients were positive for both Schirmer I and USWC tests, giving a minimum prevalence of sSS at 3.6%. There were no differences in RA patients with and without sSS regarding age, sex, disease duration, disease activity score (DAS-28) and seropositivity for anti-cyclic citrullinated protein. RA patients with sSS had a tendency for higher numbers of tender and swollen joints and pain. None of the RA patients treated with tumor necrosis factor (TNF) inhibitors had sSS, compared to 22% of the rest of the RA population studied. The treatment of the RA patients with and without sSS was not different. Conclusion: Among the 307 RA patients, 28% had at least one sicca symptom. The estimated minimum of prevalence of sSS in 307 RA patients was 3.6%. Secondary Sjögren's syndrome was not found in RA patients treated with biologics such as TNF blockers.