Table 1.

Baseline characteristics of RA patients included in the IL-33 ancillary study from the SMART trial and a comparison between the patients in the SMART cohort included in the IL-33 study (cohort 1, n = 111) and the rest of the cohort not assessed for serum IL-33 level (n = 113)

	Cohort 1	Patients in the SMART cohort without IL-33 dosage	Whole SMART cohort	Inter-group comparison
	(n = 111)	(n = 113)	(n = 224)
Age (years)	56 ± 11	56 ± 11	56 ± 11	0.99
Female	95 (86%)	92 (81%)	187 (84%)	0.401
Disease duration (years)	11 (1–42)	10 (0.8–45)	11 (0.8–45)	0.094
DAS28-CRP	5.8 ± 0.8	5.8 ± 0.9	5.8 ± 0.9	0.791
HAQ-DI	1.8 ± 0.6	1.8 ± 0.6	1.8 ± 0.6	0.753
Prednisone treatment	76 (68%)	88 (78%)	165 (74%)	0.11
Prednisone dosage (mg/day)	8 (2–20)	10 (2–15)*	10 (2–20)*	0.243
MTX (mg/week)	14 ± 4	14 ± 4	14 ± 4	0.351
Previous biologic: None/mAb/Eta	8 (7%)/66 (60%)/37(33%)	7 (6%)/70(62%)/36(32%)	15 (7%)/136 (61%)/73(33%)	0.914
Positive RF	76 (69%)	68 (61%)	144 (65%)	0.226
Positive anti-CCP	92 (83%)	78 (70%)	170 (76%)	0.02
Serum IgG level (g/L)	11.8 (4.6–19.2)	12 (5.4–23.3)	12 (4.6–23.3)	0.564
CRP level (mg/L)	12 (0.4–139)	11 (0.3–102)	11 (0.3–139)	0.938
Radiographic erosions	100 (90%)	98 (87%)	198 (88%)	0.432
MTX duration (years)	3.6 (0.1–20.8)	3.2 (0.3–20.5)	3.5 (0.1–20.8)	0.856
Time since last anti-TNF (months)	2.7 (0.6–64.4)	2.8 (1.2–73.6)	2.7 (0.6–73.6)	0.458

Values are shown as means and standard deviations (mean ± SD) or medians (range) for continuous data, and n (%) for qualitative data

*Some patients had a deviation protocol concerning the authorized prednisone dosage

anti-CCP anti-cyclic citrullinated peptide antibody, CRP C-reactive protein, DAS28 Disease Activity Score in 28 joints, Eta etanercept, HAQ-DI Health Assessment Questionnaire—Disease Index, IL interleukin, mAb monoclonal antibody, MTX methotrexate, RF rheumatoid factor, TNF tumor necrosis factor