Table 1 Baseline characteristics and antibody positivity

RA (2010 criteria), n (%)

356 (100%)

-

Female sex, n (%)

243 (68%)

-

Age, mean years (SD)

51.2 (13.2)

-

Symptom duration (weeks), median (IQR)

18 (9-35)^a

-

Ever smokers

165 (47%)^a

-

DAS, mean ± SD

3.3 (0.9)

-

Anti-CCP2 IgG, n (%)

292 (82%)

168 (80%)

Anti-CCP2 IgM, n (%)

146 (41%)

62 (30%)

Anti-CCP2 IgA, n (%)

150 (42%)

58 (28%)

RF IgM, n (%)

267 (75%)

121 (58%)

RF IgA, n (%)

212 (60%)^a

84 (40%)^a

Anti-CarP IgG, n (%)

175 (49%)

64 (31%)

Anti-CarP IgM, n (%)

141 (40%)

35 (17%)

Anti-CarP IgA, n (%)

109 (32%)^a

23 (11%)

Anti-cetyl-Lysine IgG, n (%)

130 (37%)

67 (32%)

Anti-Acetyl-Ornithine IgG, n (%)

252 (71%)

132 (63%)

Anti-Cit-Vim IgG, n (%)

208 (58%)

100 (48%)

Anti-Cit-Fib α IgG, n (%)

101 (28%)

29 (14%)

Anti-Cit-Fib β IgG, n (%)

213 (60%)

105 (50%)

Anti-Cit-Eno IgG, n (%)

115 (32%)

58 (28%)

Number of isotypes, median (IQR)

4 (2–6)^a

3 (1–4)^a

Number of AMPAs, median (IQR)

4 (2–-6)

4 (2–5)