Colombian researchers have shown that a family history of rheumatoid arthritis (RA) is consistently associated with the early appearance of substantial radiographic joint damage (ASRD).
“RA progresses more rapidly in some patients than in others and diverse factors influence radiographic progression in a specific population,” note Juan-Manuel Anaya (Rosario University, Bogota) and co-authors in the Journal of Autoimmunity.
Anaya and team therefore searched for variables associated with an early appearance of substantial joint damage in 157 patients with RA using radiographic assessments.
They collected information on patient demographics and cumulative clinical and laboratory manifestations over an average of 3.2 years, including family history of RA, extra-articular manifestations, rheumatoid factor, anti-cyclic citrullinated peptide (CCP)3 antibodies, tumor necrosis factor single nucleotide polymorphism at –308 position genotype, and HLA-DRB1 status.
The researchers report that when a Sharp–van der Heijde erosive score of greater than 5 was used to define substantial joint damage, early ASRD was significantly associated with a family history of RA, an increased number of shared epitope (SE) alleles, and anti-CCP3 seropositivity.
After adjusting for potential confounders, the likelihood of substantial damage in a patient positive for anti-CCP3 was 99% higher than for a patient negative for anti-CCP3.
Having an additional SE allele was associated with a 56% increase in the risk for appearance of substantial joint damage. In addition, family history of RA increased the risk for substantial joint damage by a factor of 3.
When a joint space narrowing score of greater than 5 was used to define substantial joint damage, a family history of RA (hazard ratio
=5.45), the number of SE alleles (HR=1.54), and female gender (HR=2.42) were significantly associated with early ASRD.
Anaya and team conclude that family history of RA is a key risk factor for joint damage but may depend on the population studied because genetic and environmental variation are population specific.
They add: “Our results emphasize the usefulness of assessing familial disease, testing anti-CCP antibodies and genotyping HLA-DRB1 gene in patients with RA because these factors may be used to predict clinical outcomes and guide therapeutic interventions.”