Table 2 Characteristics of the patients with rheumatoid arthritis stratified by calprotectin percentiles. All results are mean (with standard deviation), except those with an asterisk* which are median [with interquartile range] and those marked with a “§” which are number of patients (%). Abbreviations: BMI body mass index, CRP C-reactive protein, ESR erythrocyte sedimentation rate, RADAI Rheumatoid Arthritis Disease Activity Index, HAQ Health Assessment Questionnaire, CDAI Clinical Disease Activity Index, DAS28 28-joints Disease Activity Score, US ultrasound, SONAR Swiss Sonography in Arthritis and Rheumatism, ACR/EULAR American College of Rheumatology/European League Against Rheumatism, RF rheumatoid factor, ACPA anti-citrullinated peptide antibodies
From: Serum calprotectin: a promising biomarker in rheumatoid arthritis and axial spondyloarthritis
Serum calprotectin quartile [μg/ml] | 0–1.7 | 1.7–2.6 | 2.6–4.3 | 4.3–13 | p value |
|---|---|---|---|---|---|
n | 243 | 242 | 242 | 242 | Â |
Age years | 56.6 (13.0) | 57.2 (13.0) | 58.3 (13.8) | 58.3 (12.8) | 0.41 |
Elderly onset§1 | 38 (15.6) | 51 (21.1) | 45 (18.6) | 43 (17.8) | 0.77 |
Disease duration, years | 10.6 (10.1) | 10.8 (10.0) | 10.8 (10.0) | 11.3 (10.5) | 0.92 |
Gender = male§ | 53 (21.8) | 56 (21.3) | 65 (26.9) | 76 (31.4) | 0.01 |
BMI kg/m2 | 25.3 (5.0) | 26.3 (5.5) | 26.3 (5.9) | 27.0 (5.2) | 0.16 |
CRP mg/l* | 2.0 [1.0, 4.6] | 2.0 [1.0, 7.0] | 2.2 [1.0, 7.0] | 4.2 [2.0, 12.0] | < 0.01 |
ESR mm/h* | 8.0 [5.0, 16.0] | 10.0 [6.0, 20.0] | 12.0 [5.5, 22.5] | 16.0 [8.0, 30.0] | < 0.01 |
Tender joint count | 2.6 (4.3) | 3.2 (4.8) | 3.6 (5.2) | 4.0 (5.6) | 0.02 |
Swollen joint count | 1.3 (2.5) | 1.7 (2.8) | 2.2 (3.3) | 3.4 (4.5) | < 0.01 |
RADAI score | 2.3 (1.8) | 2.9 (2.2) | 2.9 (2.2) | 3.3 (2.2) | < 0.01 |
HAQ | 0.6 (0.6) | 0.8 (0.7) | 0.8 (0.7) | 1.0 (0.7) | < 0.01 |
CDAI | 7.3 (7.9) | 9.8 (9.9) | 11.2 (11.7) | 12.3 (13.4) | < 0.01 |
DAS28 CRP | 2.5 (1.0) | 2.8 (1.1) | 2.8 (1.2) | 3.2 (1.4) | < 0.01 |
DAS28 ESR | 2.6 (1.3) | 2.9 (1.3) | 3.0 (1.3) | 3.5 (1.5) | < 0.01 |
DAS28 ESR moderate/high§2 | 58/190 (30.5) | 78/196 (39.8) | 83/193 (43.09) | 118/200 (59.0) | < 0.01 |
DAS28 ESR remission §3 | 103/190 (54.2) | 86/196 (43.9) | 78/193 (40.4) | 60/200 (30.0) | < 0.01 |
US score B mode score | 8.9 (6.5) | 9.1 (6.3) | 10.4 (5.3) | 11.6 (8.7) | 0.13 |
US Power Doppler score | 2.2 (5.9) | 2.0 (4.0) | 2.0 (3.0) | 4.7 (6.1) | 0.01 |
SONAR positive§ | 28/44 (63.6) | 30/47 (63.8) | 31/47 (66.0) | 58/71 (81.7) | 0.02 |
ACR/EULAR 2010 Criteria | 6.7 (2.1) | 7.1 (2.1) | 7.3 (2.2) | 7.6 (2.1) | < 0.01 |
RF positive§ | 157/232 (67.7) | 164/233 (70.4) | 172/228 (75.4) | 179/236 (75.8) | 0.02 |
ACPA positive§ | 144/226 (63.7) | 145/223 (65.0) | 158/217 (72.8) | 159/227 (70.0) | 0.06 |
Rheumatoid nodules§ | 36/232 (15.5) | 51/232 (21.9) | 46/226 (20.3) | 59/223 (26.4) | 0.01 |