To determine factors influencing the age at onset of rheumatoid arthritis (RA).
A sample of 152 Colombian patients was investigated. Hazard ratios (HRs) that measured the effect size of risk factors on the age at RA onset were computed by using Cox regression models.
Positive anti-CCP antibodies were associated with an increased risk of early RA onset (HR = 1.60; 95% confidence interval, [1.06, 2.4]), whereas the presence of the protective (70)DERAA(74) sequence was associated with a delayed onset (HR = 0.55; [0.33, 0.92]). After controlling for both anti-CCP antibodies and the (70)DERAA(74) sequence, the following variables did not influence significantly the age at RA onset: gender, ever cigarette smoking, family RA history, the TNF-308 A polymorphism, HLA shared epitope, and the presence of rheumatoid factor.
Anti-CCP antibodies and the HLA-DRB1 (70)DERAA(74) sequence influence the age at onset of RA.