A connection between prevalence of rheumatoid arthritis (RA) and periodontitis has been reported. The hypothesis for this association involves increased citrullination in the oral mucosa in patients with periodontitis. Whether ongoing periodontitis has an effect on IgA antibodies to citrullinated peptides (ACPA) in saliva is unknown. We studied IgA ACPA in saliva and serum and their relation to periodontitis and smoking in a population-based elderly RA cohort.
A population-based cohort of patients with RA ≥61 years of age (n=132) was examined by rheumatologists and a dental hygienist. Analyses of IgG ACPA in serum and IgA ACPA in serum and saliva were performed. The presence of ACPA was compared in patients with RA with and without periodontitis.
IgA ACPA in serum occurred in 35% of RA patients with periodontitis and in 43% of RA patients without periodontitis (p=0.740). IgG ACPA in serum was found in 66% of RA patients with periodontitis, and in 69% without periodontitis (p=0.740). IgA ACPA in saliva occurred in 20% with periodontitis and 55% without periodontitis (p=0.062). A logistic regression analysis adjusting for age, gender and smoking gave an odds ratio (OR) of 0.456 (95% CI=0.183-1.137, p=0.092) for saliva IgA ACPA positive individuals to have periodontitis.
IgA ACPA in serum or saliva was not more common in RA patients with periodontitis. This implies that local production of ACPA by the oral mucosa is not enhanced by periodontal inflammation, in patients with established RA.