Anti-CCP-positive RA | Anti-CCP-negative RA | |||
---|---|---|---|---|
*04:05, *09:01/Smoking | No. Cases | OR† (95% CI) | No. Cases | OR† (95% CI) |
No/− | 188 | reference | 58 | reference |
No/+ | 30 | 2.20 (1.27–3.82) | 13 | 2.99 (1.38–6.47) |
Single/− | 570 | 5.95 (4.75–7.47) | 74 | 2.39 (1.64–3.47) |
Single/+ | 112 | 10.33 (6.32–16.87) | 15 | 4.47 (2.05–9.73) |
Double/− | 160 | 19.86 (12.49–31.56) | 13 | 4.65 (2.25–9.62) |
Double/+†† | 20 | 23.93 (7.54–75.96) | 7 | 24.22 (6.33–92.68) |
Heterozygote/− | 78 | 27.85 (13.51–57.39) | 12 | 12.72 (5.08–31.86) |
Heterozygote/+ | 12 | 67.46 (8.34–545.62) | 4 | 65.92 (6.60–657.94) |
↵† OR were calculated by comparing each group with the corresponding reference group [individuals without HLA-DRB1 risk alleles (*01:01, *04:01, *04:04, *04:05, *04:08, *04:10, *09:01, *10:01)], and were adjusted for age and sex.
↵†† Double indicates DRB1 *04:05/*04:05 or *09:01/*09:01 or *04:05/*09:01. Heterozygote indicates DRB1*04:05/*09:01. Anti-CCP: anticyclic citrullinated peptide autoantibodies; RA: rheumatoid arthritis.