Table 3 Frequency of occurrence of different autoantibodies assessed at baseline and after 1 year of treatment with anti‐tumour necrosis factor α agents according to clinical response.
| Autoantibody | Responders (83 patients) | Non‐responders (37 patients) | ||||
|---|---|---|---|---|---|---|
| Baseline | 1 year | p Value | Baseline | 1 year | p Value | |
| RF (nephelometry) | 69 | 61 | 0.186 | 33 | 32 | 1 |
| IgM‐RF | 65 | 59 | 0.372 | 31 | 30 | 1 |
| IgA‐RF | 51 | 41 | 0.159 | 25 | 26 | 1 |
| IgG‐RF | 48 | 41 | 0.350 | 26 | 23 | 0.623 |
| Anti‐CCP | 60 | 58 | 0.864 | 32 | 31 | 1 |
Anti‐CCP, anti‐cyclic citrullinated peptide antibodies; RF, rheumatoid factor.