Table 1 Clinical and demographic characteristics of the study participants

Female: Male

69:31

189:36

Age (years)

44.32 (21–66)

57.71 (27–87)

 < 0.001

CRP (IU/mL)

2.6 (0.5–6.0)

19.3 (1.0–127.0)

0.003

ESR (mm/h)

9.7 (2.0–24.0)

43.8 (2.0–140.0)

0.002

IgA (IU/mL)

2.1 (0.9–3.9)

2.6 (0.2–6.4)

0.16

IgG (IU/mL)

12.8 (9.4–19.8)

14.2 (5.9–50.7)

0.39

IgM (IU/mL)

1.1 (0.4–3.2)

1.3 (0.3–4.4)

0.61

Disease duration (minimum–maximum in months)

–

9.7 (0.4–40)

DAS28-CRP (minimum–maximum)

–

3.5 (1.0–7.1)

DAS28-ESR (minimum–maximum)

–

4.0 (1.2–7.8)

Rheumatoid factor positive

–

57.8%

ACPA positive

–

42.2%

ANA positive

–

49.4%

AKA positive

–

49.4%