Objective To find the strength of association between periodontal disease (PD) and rheumatoid arthritis (RA) in non-smoking, disease modifying antirheumatic drug (DMARD)-naive RA patients in a case-control design.

Methods Patients of RA (DMARD-naive, non-smokers) satisfying the American college of Rheumatology 1987 criteria and healthy controls were included. PD was defined as present if the mean pocket depth (MPD) is ≥3 mm. Demographic data and disease specific variables were recorded for RA patients and healthy controls. Titres of immunoglobulin M-rheumatoid factor (IgM-RF) and anticitrullinated peptide antibodies (ACPAs) were measured using ELISA.

Results Patients with RA (n=91) had a 4.28 (CI 2.35 to 7.38) higher odds of PD (64.8% vs 28%, p<0.001) compared with healthy controls (n=93). The MPD was 3.61±1.22 mm in cases and 2.46±0.74 mm in controls (p<0.001). IgM-RF titres (110.56±95.81 vs 66.53±70.29; p=0.02) and ACPA titres (753.05±1088.27 vs 145.15±613.16, p=0.001) were significantly higher in RA patients with PD than those without PD. The MPD positively correlated with titres of ACPAs in RA patients (r=0.24; p=0.02).

Conclusions PD is more frequent and severe in non-smoking DMARD-naive RA patients compared with healthy controls. PD in RA is associated with high titres of ACPAs.