Table 1

Patient's baseline characteristics

CharacteristicsTotal patient population (n=105)Group A (concordant) (n=54)Group B (discordant) (n=51)p Value
Age, mean (SD), y54 (14)53 (13)56 (14)0.006
Female, no. (%)91 (87)47 (87)44 (86)ns
Dis. duration, median (IQR), y10.1 (4.6–12.6)7.6 (2.5–12.4)8.7 (2.6–13.6)ns
Initial DAS28, mean (SD)5.6 (1.2)5.5 (1.2)5.7 (1.1)ns
Biol. duration, median (IQR), y2.6 (0.6–5.3)2.9 (0.5–4.7)1.9 (0.6–6)ns
Switchers, no. (%)47 (45)31 (57)16 (31)0.01
Biologic at baseline, no. (%)
 Infliximab24 (22.9)8 (14.8)15 (29.4)
 Etanercept48 (45.7)31 (57.4)18 (35.3)
 Adalimumab33 (31.4)15 (27.7)18 (35.3)
Methotrexate use, no. (%)102 (97)52 (96)50 (98)ns
Corticosteroids use, no. (%)103 (98)53 (98)50 (98)ns
DAS28 study baseline, mean (SD)4.1 (1.3)3.9 (1.6)4.2 (1.1)0.003
RF positive, no (%)72 (70)34 (63)38 (79)ns
ACPA positive, no (%)75 (73)38 (70)37 (75)ns
Erosive disease, no. (%)56 (62)29 (62)27 (63)ns
ESR, median (IQR), mm/h29 (16–52)29 (19–41)33 (21–50)ns
CRP, median (IQR), mg/l2.9 (1.2–4.5)3.9 (2–8)3.6 (2–7)ns
  • Values shown are n (%), means (SD) or median (IQR).

  • Differences between patients’ baseline characteristics were tested by Mann–Whitney U or χ2 tests.

  • Infliximab was administered at 3 mg/kg intravenous at 0, 2, 6, 14 weeks and every 8 weeks thereafter. Adalimumab was administered 40 mg subcutaneous every other week. Etanercept was administered 25 mg subcutaneous twice a week or 50 mg once a week.

  • Switchers=patients who have been previously exposed to biologic therapy and switch to a new agent.

  • ACPA, anticitrullinated peptides antibodies; Biol, biologic; CRP, C-reactive protein; DAS, disease activity score; Dis, disease; ESR, erytrocyte sedimentation rate; Initial DAS28, DAS before biologic therapy; ns, non-significant; RF, rheumatoid factor.