Association of the clinical presentation and disease activity index in Sjogren's syndrome

Investigate the impact of different clinical presentation on disease activity in patients with primary Sjogren’s syndrome. The retrospective study including data about 40 outpatients who visited a rheumatologist in SIA “ORTO klīnika” from 2014 to 2020 with diagnosis defined as M35.0 by the ICD-10. Disease activity measured by EULAR Sjogren’s syndrome activity index (ESSDAI). 40 patients – 36 women and 4 men with mean age 55.5 years (±2.14; SD=13.55). Average disease manifestation age – 48.4 years (±1.93; SD=12.23), average disease activity index – 12.6 points (±1.28; SD=8.1). Complains about dry mouth had 32 patients, dry eyes – 26, parotid gland enlargement or ultrasonographic inflammation – 23, articular involvement – 26, renal – 20, skin – 9, lungs – 9, neural – 7. Changes in complete blood count tests were common finding: lymphopenia was observed in 15 patients, anaemia -12, leukopenia or neutropenia -10, thrombocytopenia -3. Immunological changes were found in majority of patients: ANA had 39 patients, ENA -38, SS-A/Ro -36, SS-B/La -19, rheumatoid factor -29, polyclonal hypergammaglobulinemia -27, hypocomplementemia -12 (only 25 from 40 checked). Higher disease activity index was in association with lymphopenia (16.6 vs 10.2 points; p=0.014), anaemia (18.1 vs 10.77 points; p=0.011), renal (14.85 vs 10.35 points; p=0.017) and lung (18.89 vs 10.77 points; p=0.006) involvement, lower disease activity – in association with articular involvement (10.54 vs 16.43 points; p=0.026). Lymphocyte count (k=-0.48; p=0.02) and ANA (k=0.51; p=0.002) moderately correlates with disease activity index, rheumatoid factor level – have only weak correlation (k=0.334; p=0.04). Anaemia, lymphopenia, renal and lung involvement associated with more severe disease course, but articular involvement – with less severe. High antinuclear antibody and rheumatoid factor level are characteristic for Sjogren’s syndrome and important in the diagnosis, but are not strong markers of the disease activity.