Table 1. Clinical and serological characteristics at inclusion.
| Healthy controls(n = 16) | SAP(n = 34) | RA patients(n = 12) | |
|---|---|---|---|
| Sex, n (% female) | 12 (75) | 24 (71) | 8 (67) |
| Age, yr, median (IQR) | 53 (50–59) | 50 (38–56) | 59 (52–70)* |
| SE status (% pos)a | 62.5 | 69 | 67 |
| CRP (mg/L), median (range) | NA | <5 (<5–29) | 17 (<5–43)*** |
| ESR (mm/h), median (IQR) | NA | 11 (9–17) | 28 (21–43)** |
| Anti-CCP2 positive, n (% pos) | NA | 33 (97) | 9 (75) |
| Anti-CCP2 (U/ml), median (IQR) | NA | 99 (39–299) | 240 (136–340) |
| RF positive, n (% pos) | NA | 29 (85) | 9 (75) |
| RF (IU/ml), median (IQR) | NA | 54 (21–146) | 346 (104–535)** |
| Lymphocyte count (106/ml), median (range)b | 1.85 (1.38–3.1) | 2.05 (0.9–4.35) | 1.90 (1.37–3.01) |
| CD4+ T-cell count (106/ml), median (range)b | 0.88 (0.46–1.57) | 1.01 (0.37–2.44) | 0.86 (0.64–1.51) |
| CD8+ T-cell count (106/ml), median (range)b | 0.38 (0.26–0.74) | 0.36 (0.11–0.94) | 0.36 (0.15–1.13) |
| CD19+ B-cell count (106/ml), median (range)b | 0.20 (0.14–0.48) | 0.27 (0.05–0.87) | 0.23 (0.08–0.42) |
| CD16+CD56+ NK-cell count (106/ml), median (range)b | 0.31 (0.15–0.58)** | 0.21 (0.01–0.47) | 0.24 (0.10–0.34) |
| DAS28-ESR, median (IQR) | NA | NA | 5.67 (4.11–6.10) |
| TJC46, median (IQR) | NA | NA | 8 (4–15) |
| SJC44, median (IQR) | NA | NA | 7 (2–12) |
| VASgh, median (IQR) | NA | NA | 60 (30–77) |
SE = shared epitope (SE-containing alleles are HLA-DRB1*0401, *0404, *0405, *0408, *0101, *0102 and *1001); CRP = C-reactive protein; ESR = erythrocyte sedimentation rate; Anti-CCP2 = anti cyclic citrullinated peptides antibodies (positive score defined as > 10 IU/mL); RF = rheumatoid factor (positive score defined as ≥ 15 IU/mL); DAS28-ESR = disease activity score 28 using the ESR; TJC46 = tender joint count out of a possible 46; SJC44 = swollen joint count out of a possible 44; VASgh = visible analog scale for global health. NA: not applicable. Groups are compared to SAP (seropositive arthralgia patients).
a Available for 16/16 HC, 33/34 SAP and 10/12 RA patients.
b Available for 14/16 HC, 34/34 SAP and 10/12 RA patients.
*p<0.05
**p<0.01
***p<0.001.