Table 1.
Baseline characteristics
| Variable | pSS patients (n = 49) | RA (n = 30) | HC (n = 33) | p-value |
|---|---|---|---|---|
| Age, mean, years | 47.6 ± 11.3 | 48.5 ± 10.1 | 43.3 ± 7.3 | 0.079 |
| Female, no. (%) | 47 (95.9) | 27 (90) | 30 (90.9) | 0.535 |
| Symptom duration, mean, years | 4.8 ± 5.0 | |||
| BMI, mean, kg/m2 | 22.6 ± 4.6 | |||
| Glandular manifestations | ||||
| Ocular symptoms, no. (%) | 49 (100) | |||
| Oral symptoms, no. (%) | 45 (91.8) | |||
| Extraglandular manifestations | ||||
| Photosensitivity, no. (%) | 3 (6.1) | |||
| Arthralgia, no. (%) | 25 (51.0) | |||
| Arthritis, no. (%) | 7 (14.3) | |||
| Raynaud’s phenomenon, no. (%) | 4 (8.2) | |||
| Purpura, no. (%) | 12 (24.5) | |||
| Fatigue, no. (%) | 39 (79.6) | |||
| ESSDAI | 3.67 ± 2.15 | |||
| ESSDAI ≥ 5, no. (%) | 13 (26.5) | |||
| DAS28 | 2.66 ± 1.17 | |||
| Schirmer test, left, mm | 6.19 ± 6.80 | |||
| Schirmer test, right, mm | 5.45 ± 5.20 | |||
| Salivary flow, UWS, mL/min | 0.076 ± 0.126 | |||
| Salivary flow, SWS, mL/min | 0.491 ± 0.508 | |||
| Laboratory data | ||||
| Leukocyte, /μL (normal range 3,400 ‒ 10,600) | 4969.2 ± 1929.5 | 5541 ± 2112.8 | 0.221 | |
| Hemoglobin, g/dL (normal range 12.5 ‒ 17.5) | 12.7 ± 1.16 | 12.9 ± 1.39 | 0.656 | |
| Platelet, 103/μL (normal range 134 ‒ 387) | 238.3 ± 56.2 | 236.2 ± 67.4 | 0.881 | |
| ESR, mm/hr (normal range 0 ‒ 25) | 27.3 ± 22.8 | 16.7 ± 11.4 | 0.008 | |
| CRP, mg/dL (normal range 0 ‒ 0.5) | 0.34 ± 0.88 | 0.30 ± 0.58 | 0.863 | |
| Total protein, g/dL (normal range 6.6 ‒ 8.7) | 7.8 ± 0.77 | 7.17 ± 0.43 | < 0.001 | |
| Albumin, g/dL (normal range 3.5 ‒ 5.2) | 4.5 ± 0.28 | 4.46 ± 0.21 | 0.525 | |
| RF positivity, no. (%) | 30 (61.2) | 28 (93.3) | 0.002 | |
| ANA positivity, no. (%) | 46 (93.9) | |||
| Anti-SSA/Ro positivity, no. (%) | 44 (89.8) | |||
| Anti-SSB/La positivity, no. (%) | 11 (22.4) |
Mean ± SD. pSS, primary Sjogren’s syndrome; RA, rheumatoid arthritis; HC, healthy control; BMI, body mass index; RTA, renal tubular acidosis; ESSDAI, European League Against Rheumatism Sjogren’s Syndrome disease activity index; DAS28, disease activity score of 28 joints; UWS, unstimulated whole saliva; SWS, stimulated whole saliva; ESR, erythrocyte sedimentation rate; CRP, c-reactive protein; RF, rheumatoid factor; ANA, antinuclear antibody
Bold values indicate significant p-value