Background It has been suggested that functional disability in patients with rheumatoid arthritis (RA) could influence in hygiene procedure performance,promoting the development of periodontitis (P).However, this factor has been tested in few studies, with inconsistent data^1,2. Hence, it has been implied both that functional disability has a possible role in P process risk (13,4%)²,and that there is no higher plaque index³ (PI) or no association between P severity and functional index by HAQ⁴.

Objectives 1)To test whether the functional ability of RA patients is associated with the presence of a more severe P.2) To describe the possible influence of functional disability on the development of P in terms of RA activity.

Methods Observational,cross-sectional,case-control study,performed in adult RA patients (ACR/EULAR 2010) in a Rheumatology Service; and a control group with a non-inflammatory joint pathology,with at least 4 teeth,without dental prophylaxis or antibiotic intake 6 months before. RA activity was evaluated:DAS28 (ESR), DAS28(CRP) and SDAI, and patients were categorized by activity and functional disability (HAQ index).Periodontal parameters:PI (Silness and Löe,1964)⁵,4 surfaces/tooth (0–3);bleeding on probing (BoP), probing pocket depth (PPD), clinical attachment level (CAL). Dental team:2 periodontists/2 general dentists (inter-observer variability<30%). Full mouth CAL,PPD and periapical x-rays were taken. CAL was classified according to the European Workshop 2005 (Tonetti):level 0 (absence), N1 T (mild), N2 T (severe). Statistical Analysis:t-student, Kruskal Wallis, Chi-square. Statistical program: Stata 13.1.

Results 344 patients:187RA (147 F/40 M)and 157 control (101F/56M),mean age 54,9 (17,9), follow-up 8,8 years;18,72% patients with early RA. 83/187 (44,39%) RA patients presented a remission/low disease activity and 55,61%, moderate/high activity. 69,05% patients had P N2 T. Mean HAQ index was 0,76 (0,62), finding differences between patients with varied disease activity:p50 [p25-p75] 0,250 (0–0,750) in RA patients with remission/low activity vs 1,125 (0,625–1,5) those with moderate/high activity, p=0,000. There was no association between HAQ values and presence of P (OR 1,0003 IC 95% 0,999–1,001). Nevertheless, there was a gradually increase in PI values from control patients 0,56 (0,40), to remission/low RA activity 0,59 (0,37), RA moderate/high 0,86 (0,53), with statistically significant differences between consecutive categories (p<0,001 and p=0,001, respectively).

Conclusions 1. No association was found between functional ability of RA patients measured by HAQ index and presence of a more severe P.2. An ascendant gradient in PI is observed related to RA clinical activity with significant difference, despite an acceptable preserved functional ability.3. These findings could strenghten an classic risk factor independent relationship between RA and P.

1. de Pablo P,et al. J Rheumatol 2008;

2. Pischon N,et al. J Periodontol 2008;

3. .Mercado FB, et al. J Periodontol. 2001;

4. Dissick A, et al J Periodontol. 2010;

5. Silness J,Loe H. Acta Odontol Scand 1964.

Disclosure of Interest None declared