Table 1

EAC: number of autoantibodies and clinical characteristics at presentation

n=8280 (n=261)1 (n=138)2 (n=139)3 (n=290)Ordinal OR (95% CI)p ValueMultivariable
ordinal OR (95% CI)
p Value
Age (years), M±SD60±1659±1753±1655±15Per 10 years: 0.85 (0.79 to 0.92)<0.001*0.87 (0.79 to 0.95)0.001
Female, n (%)171 (66)99 (72)95 (68)190 (66)0.98 (0.75 to 1.27)0.868
BMI (kg/m2), M±SD26.5±4.026.0±3.825.1±3.125.3±3.80.93 (0.90 to 0.97)<0.001*0.95 (0.92 to 0.99)0.022
Smoking (ever), n (%)115 (45)70 (52)71 (53)167 (59)1.51 (1.17 to 1.94)0.001*1.52 (1.17 to 1.97)0.001
Family history of RA, n (%)50 (20)35 (26)37 (28)85 (30)1.47 (1.11 to 1.96)0.0081.45 (1.08 to 1.95)0.015
(Sub-)Acute onset symptoms, n (%)157 (66)82 (59)66 (48)145 (51)0.70 (0.54 to 0.90)0.005*0.80 (0.61 to 1.05)0.104
Symptom duration (months), M±SD4.6±4.94.9±4.96.0±5.36.1±5.3Per 3 months: 1.14 (1.05 to 1.23)0.001*1.09 (1.00 to 1.18)0.044
Location start of symptoms, n (%)
 Small joints150 (60)75 (54)78 (56)166 (58)1 (ref)0.279
 Large joints36 (14)22 (16)20 (14)53 (18)1.22 (0.85 to 1.73)0.806
 Both64 (26)41 (30)41 (30)68 (24)0.96 (0.72 to 1.29)
Symmetric start of symptoms, n (%)179 (77)101 (79)93 (72)177 (68)0.70 (0.52 to 0.94)0.017
Start symptoms in, n (%)
 Upper extremity120 (54)71 (60)46 (37)92 (36)1 (ref)<0.001
 Lower extremity24 (11)14 (12)17 (14)46 (18)2.18 (1.46 to 3.24)†<0.001*
 Both78 (35)34 (29)61 (49)115 (46)1.71 (1.29 to 2.27)†
ESR (mm/hour), M±SD36±2537±2638±2742±29Per 10 mm/hour: 1.06 (1.02 to 1.11)0.0091.14 (1.08 to 1.21)<0.001
CRP (mg/L), M±SD32±3627±3130±4230±331.00 (1.00 to 1.00)0.743
SJC in 28 joints, M±SD9±68±67±57±50.95 (0.93 to 0.97)<0.001*0.95 (0.93 to 0.97)<0.001
TJC in 28 joints, M±SD11±89±68±79±60.97 (0.95 to 0.99)0.002*
HAQ score, M±SD1.2±0.71.2±0.71.0±0.71.0±0.70.81 (0.67 to 0.97)0.0230.85 (0.69 to 1.05)0.126
SHS score, M±SD8±99±109±149±111.01 (0.99 to 1.02)0.435
VAS general health, M±SD41±2644±2441±2541±251.00 (0.99 to 1.01)0.760
DAS28-ESR, M±SD5.2±1.45.1±1.14.8±1.45.1±1.10.93 (0.84 to 1.03)0.143
  • Significant p values (p<0.05) are shown in bold typeface.

  • EAC univariable and multivariable ordinal regression analyses for increasing number of autoantibodies present. ORs of imputed data sets are pooled.

  • *Significant after correction for multiple testing (only performed in univariable analysis).

  • †Test of parallel lines significant. Joint symptoms refer to any signs or symptoms of synovitis (eg, pain, swelling and tenderness). Onset of symptoms was (sub-)acute when symptoms started within 1 week. Patient data were partly missing for a number of baseline variables, in particular for BMI, TJC28, HAQ, VAS general health and DAS28-ESR. Multivariable analysis was performed after exclusion of variables not available in BARFOT and of TJC28 due to high correlation.

  • BARFOT, Better Anti-Rheumatic Farmaco-Therapy; CRP, C-reactive protein; DAS28-ESR, 28 joints-disease activity score using erythrocyte sedimentation rate; EAC, Early Arthritis Cohort; HAQ, Health Assessment Questionnaire; RA, rheumatoid arthritis; SHS, Sharp–van der Heijde Score; VAS, Visual Analog Scale.