Demographics and disease characteristics for the entire cohort and separated by fulfilment of the ACR/EULAR classification criteria
| All patients | pSS patients | Non-pSS patients | pSS patients vs non-pSS patients, p value | |
| No of patients | 134 | 43 | 91 | |
| Age (mean±SD) | 55.5±15.8 | 60.2±13.9 | 53.3±16.2 | 0.01 |
| Sex, women | 110 (82%) | 39 (91%) | 71 (78%) | 0.12 |
| Symptom duration >2 years | 56 (42%) | 28 (65%) | 28 (31%) | <0.001 |
| Anti-SSA antibodies | 61 (46%) | 38 (88%) | 23 (25%) | <0.001 |
| Anti-SSB antibodies | 20 (15%) | 16 (37%) | 4 (4%) | <0.001 |
| ANA positive | 65/131 (50%) | 37/43 (86%) | 28/88 (32%) | <0.001 |
| IgM-RF positive | 24/78 (31%) | 15/24 (63%) | 9/54 (17%) | <0.001 |
| Anti-CCP positive | 3/85 (3%) | 1/28 (4%) | 2/57 (4%) | 1.00 |
| Schirmer’s test positive | 20 (15%) | 16 (37%) | 4 (4%) | <0.001 |
| Sialometry positive | 62 (46%) | 32 (74%) | 30 (33%) | <0.001 |
| Performed labial salivary gland biopsies (positive) | 45 (34%) (15 (11%)) | 16 (37%) (14 (33%)) | 29 (32%) (1 (1%)) | <0.001 |
| Parotid glands: highest US score (0/1/2/3) | 53 (40%)/51 (38%)/17 (13%)/13 (10%) | 6 (14%)/14 (33%)/12 (28%)/11 (26%) | 47 (52%)/37 (41%)/5 (5%)/2 (2%) | <0.001 |
| Submandibular glands: highest US score (0/1/2/3) | 25 (19%)/70 (52%)/22 (16%)/17 (13%) | 4 (9%)/9 (21%)/15 (35%)/15 (35%) | 21 (23%)/61 (67%)/7 (8%)/2 (2%) | <0.001 |
| All glands: highest US score (0/1/2/3) | 20 (15%)/71 (53%)/23 (17%)/20 (15%) | 2 (5%)/10 (23%)/15 (35%)/16 (37%) | 18 (20%)/61 (67%)/8 (9%)/4 (4%) | <0.001 |
| At least one gland with US score 1, 2 or 3 | 114 (85%) | 41 (95%) | 73 (80%) | 0.04 |
| At least one gland with US score 2 or 3 | 43 (32%) | 31 (72%) | 12 (13%) | <0.001 |
| At least one gland with US score 3 | 20 (15%) | 16 (37%) | 4 (4%) | <0.001 |
| At least two glands with US score 1, 2 or 3 | 97 (72%) | 38 (88%) | 59 (65%) | 0.008 |
| At least two glands with US score 2 or 3 | 37 (28%) | 30 (70%) | 7 (8%) | <0.001 |
| At least two glands with US score 3 | 17 (13%) | 15 (35%) | 2 (2%) | <0.001 |
P values, t-test for continuous variables, χ2 test for categorical variables and Cochran-Armitage test of trend for ordered categorical variables. Data on ANA, IgM-RF and anti-CCP were missing in 3, 56 and 49 patients, respectively.
ACR, American College of Rheumatology; ANA, antinuclear antibodies; CCP, cyclic citrullinated peptide; IgM-RF, IgM rheumatoid factor; non-pSS, patients without pSS; non-pSS patients, 2016 ACR/EULAR criteria for primary SS not fulfilled (below 4 points, 27 patients had 1-3 points according to the 2016 ACR/EULAR criteria but did not have labial salivary gland biopsy); pSS, primary Sjögren’s syndrome; SS, Sjögren syndrome; US, ultrasonography.