Table 2

Baseline characteristics (n=219)

VariableACPA-positive individuals* (n=109)RF-positive individuals*
Seronegative individuals with CSA
FDRs of patients with RA†
Age‡49 (12.9)54 (13.2)45 (12.6)57 (9.5)
Females (%)72647289
Symptom duration (months)§23 (10–52)30 (12–60)11 (4–39)22 (7–51)
Tender joint count (44 joints)0 (0–2)0 (0–2)2 (0–7)1 (0–3)
VAS pain (mm)§18 (2–56)27 (3–47)56 (34–71)ND
VAS patient global assessment (mm)§28 (3–56)22 (0–49)48 (25–69)ND
VAS fatigue (mm)§50 (9–80)33 (6–59)65 (40–82)ND
Current smoking (%)24152517
FDR with RA (%)§292128100
  • *ACPA-positive individuals: with or without RF positivity, RF-positive individuals: only RF-positive.

  • †FDRs of patients from Switzerland with RA were used as comparison cohort.

  • ‡Mean (SD), all other continuous variables mentioned as median (25th–75th percentile).

  • §Missing values; 2% for VAS global and family history, 3% for VAS pain, 4% for VAS fatigue, 6% for symptom duration, one individual for RF (marked as ACPA positive only now).

  • Netherlands: ACPA+ n=71; RF+ n=40; seronegative n=14.

  • UK: ACPA+ n=21; RF+ n=8; seronegative n=40.

  • Sweden: ACPA+ n=15; RF+ n=0; seronegative n=0.

  • Austria: ACPA+ n=2; RF+ n=5; seronegative n=3.

  • Switzerland: ACPA+ n=6; RF+ n=1; seronegative n=11.

  • ACPA, anticitrullinated protein antibodies; CSA, clinically suspect arthralgia; FDR, first degree relative; ND, not done; RA, rheumatoid arthritis; RF, rheumatoid factor; VAS: Visual Analogue Scale.