Table 6.
Association between anticyclic citrullinated peptide antibody and rheumatoid factor with shared epitope alleles according to the du Montcel classification
| aCCP | RF | |||
|---|---|---|---|---|
| Allele | OR (95% CI) | P value | OR (95% CI) | P value |
| S1 allele (n = 55) | 2.9 (0.7 to 12.4) | 0.2054 | 4.5 (1.2 to 16.9) | *0.0291 |
| S2 allele (n = 28) | 12.0 (2.4 to 59.5) | 0.0019** | 8.3 (1.6 to 43.3) | *0.0122 |
| S3D allele (n = 38) | 7.5 (1.8 to 31.4) | 0.0100* | 5.3 (1.3 to 22.7) | *0.0246 |
| S3P allele (n = 61) | 13.3 (3.2 to 54.4) | 0.0003*** | 4.5 (1.2 to 16.8) | *0.0264 |
| X allele (n = 64) | 4.7 (1.2 to 17.6) | 0.0213* | 2.7 (0.8 to 9.8) | 0.1678 |
aCCP = anticyclic citrullinated peptide antibodies; RF = rheumatoid factor. du Montcel classification is from du Montcel et al. [7]. OR (95% CI) and P values were calculated using Fisher's exact test to compare with SE noncarrier rheumatoid arthritis patients (n = 12). *P < 0.05. **P ≤ 0.001 and ***P ≤ 0.0003 values are highly significant.