Secondary Sjogren's Syndrome in 83 Patients With Rheumatoid Arthritis

Sjogren syndrome (SS) can occur alone, primary Sjogren syndrome, or in association with other rheumatic diseases, secondary Sjogren syndrome (sSS), such as Rheumatoid arthritis (RA). The occurrence of Sjogren syndrome with RA makes it course worse and increases high morbidity and mortality of RA. In this exploratory study we aim to determine the prevalence of sSS (diagnosed based on the revised version of American-European consensus Group Classification Criteria: AUCG-criteria), sicca symptoms (dry eye, dry mouth), positive autoantibody tests (Anti RO or Anti-LA antibodies), UWSFR (Unstimulated Whole Salivary Flow Rate), Schirmer and Lissamine test. In this cross-sectional study, eighty three consecutive RA patients (according to American College of Rheumatology criteria 1987) who were visited at rheumatology clinic of Razi General Hospital located in the north of Iran entered into our study. Our exclusion criteria was a positive history of past head and neck radiation treatment, Hepatitis C infection, acquired immunodeficiency disease (AIDS), pre-existing lymphoma, sarcoidosis, graft versus host disease, use of anticholinergic drugs (including neuroleptics, antidepressants, antihypertensive and parasympatholytics). They examined with UWSFR by a rheumatologist and with Schirmer test and Lissamine test by an ophthalmologist. Participants were 90.4% female with the mean age 48.3±13 years. Duration of RA was in 36.1% less than 5 years, in 22.9% 5-10 years, in 12.1% 11-15 years and in 28.9% more than 15 years. Our results demonstrated that the prevalence of sSS was 5.9% (CI:0.6%-10.5%). Number of 27.7% of RA patients positively responded to at least one question about sicca symptoms. Among objective tests, only Positive UWSFR and Lissamine test were significantly more common in RA patients with sSS in comparison to ones without sSS (P<0.001, P=0.01 respectively). In RA patients, we found a linear trend between sicca symptoms and aging (P=0.02). In patients with sicca symptoms, among tests that used for assessing decrease in saliva or tear production, only USWFR significantly more common (P=0.01).

In RA population in North of Iran prevalence of sSS was less than 10%. In them, a significant linear trend existed between aging and sicca symptoms. Among objective tests of AUCG-criteria (except for lip biopsy that was not performed in the current study) only UWSFR and Lissamine test were significantly more common in patients with sSS in comparison ones without it.