Table 1 Baseline characteristics of study subjects
CharacteristicsAnti-TNF group n = 64No anti-TNF group, n = 48Healthy controls n = 18p Value
Women (%)7369780.74*
Age, mean (range), years51 (23–75)46 (18–85)47 (21–75)0.23†
Gastroenterological disease (%)9330.002‡
Rheumatoid arthritis (n)5227
Juvenile chronic arthritis (n)22
M. Still (n)20
Psoriatic arthritis (n)13
Spondyloarthropathy (n)10
M. Crohn (n)615
Inflammatory bowel disease (n)01
Duration of disease activity, mean (months)1561110.041§
Prednisone (%)20230.74‡
Mean daily dose, mg790.58§
Methotrexate (%)71750.58‡
Mean weekly dose, mg16150.72§
Azathioprine (%)8170.15‡
Mean daily dose, mg1151090.73§
NSAIDs (%)57580.90‡
Prior vaccination (%)62386<0.001*
  • *χ2 test (two-sided) for anti-TNF versus no anti-TNF versus healthy controls.

  • †One-way ANOVA for anti-TNF versus no anti-TNF versus healthy controls.

  • ‡χ2 test (two-sided) for anti-TNF versus no anti-TNF.

  • §Wilcoxon rank sum test (two-sided) for anti-TNF versus no anti-TNF

  • TNF, tumour necrosis factor α; NSAIDs, non-steroidal anti-inflammatory drugs; M, morbus.