Background Positivity of anti-citrullinated peptides antibodies (ACPA) indicates severity in Rheumatoid Arthritis (RA). There is evidence for chronic periodontitis (PD) in RA autoimmune response by periodontopathogenic bacteria such as P.gingivalis, through citrullination of L-arginine.
Objectives 1.To determine whether there is an association between PD and its severity with ACPA(+).2.To assess relationship between PD and ACPA titres.3.To identify association between certain periodontal parameters and ACPA titres and their possible cutoff points.
Methods Observational, cross-sectional study RA patients ≥18 with ≥4 teeth, no tooth cleaning, antibiotic intake 6 months before.Socio-demographic and anthropometric variables, annual dental prophylaxis and comorbidities.Serum ACPA detection:Ab IgG against CCP2 (ELISA)Eurodiagnostica:positive≥25; ACPA titres stratification:Low (25–75), moderate (76–300) and high (>300). Periodontal parameters: plaque index (PI), bleeding on probing (Bop), probing pocket depth,clinical attachment level (CAL). CAL loss was categorized according to European Workshop 2005 (Tonetti):T level0 (absence), TL1 (mild), TL2 (severe). Statistical analysis:t-student, Kruskal Wallis, Chi- squared tests by Stata program 13.1.
Results 187 RA patients included (table 1),ACPA determined in 168 patients: 67.86% (+) with similar titres distribution: low 18%, moderate 26%, high 23%. PD:182 patients (97.3%):TL1 52.4%,TL2 44.9%. Although prevalence of severe PD/ACPA(+) was higher compared to PD/ACPA(-) (69.2% vs 30.7%), there was no association between PD and ACPA positivity/titres. Regarding the association with periodontal parameters, there was tendency of association between ACPA(+) and number of periodontal pockets ≥5mm (NPP),OR 1.02 (95% CI 0.9–1.04) adjusted. There was a gradient effect, where NPP increased as ACPA titles increased, which was significant for high ACPA titres (p≤0.05,OR 1.03 95% CI 1.0–1.05). When ACPA(+) was related to %PI and BoP, a strong association was observed for PI, OR 10.32 (p<0,026), and only a tendency for BoP (p<0.062). With cutoff points of 8% PI and 65% BoP, a risk for ACPA(+) was detected with an OR 2.19 and OR 2.45, respectively.
Conclusions 1.Despite higher prevalence of severe PD in ACPA(+) patients, we found no association between the presence of PD and ACPA positivity nor with serum titres. 2. On analysis of ACPA titres in relation to the severity of the periodontal parameters, there was a “gradient” risk, where NPP increased as ACPA titres increased, which was significant for high ACPA titres.3. Risk cutoff points for ACPA(+) were 8% for PI and 65% for BoP.
Disclosure of Interest None declared