Study of chronic periodontitis in rheumatoid arthritis patients and its relation to serum anticitrulinated peptide antibody levels

Background
Recently discovered evidence suggests that periodontitis might have a direct role in initiating and sustaining the immunoinflammatory responses in rheumatoid arthritis (RA), besides the risk factors that are common to both conditions.
Aim
The aim of this study was to determine the prevalence of chronic periodontitis in a cohort of Egyptian RA patients and their first-degree relatives and siblings compared with a control group and its relation to serum anticitrulinated peptide antibody (ACPA) levels.
Patients and methods
This study was carried out on three groups: group I included 100 patients with RA who fulfilled the 2010 ACR/EULAR classification criteria for RA and had less than 5 years’ disease duration. They were recruited from the Rheumatology Unit and Rheumatology Outpatient Clinic at Alexandria Main University Hospital. Group II included 50 first-degree relatives and siblings of RA patients who were free of clinical joint disease, and group III included 50 age-matched and sex-matched healthy subjects referred for general dental treatment at the Dental Clinic of Alexandria Main University Hospital. RA disease activity was assessed by applying Disease Activity Score 28, and the functional state of the patients was assessed by applying the Health Assessment Questionnaire. All subjects underwent a dental examination, including Probing Pocket Depth (PPD), Clinical Attachment Loss (CAL), Plaque Index (PI), and modified Gingival Index. The ACPA levels in serum were evaluated in group I, group II, and group III participants with periodontitis.
Results
Group I patients had significantly more periodontitis than group II (<0.001) and group III (<0.001). There was a statistically significant difference between group I and group II in PPD (<0.001), CAL (<0.001), and PI (<0.001) and a statistically significant difference between group I and group III in PPD (=0.001), CAL (=0.006), and PI (=0.002). In group I, 82 (82%) patients had positive serum ACPA (20 U/ml), compared with only four (8%) subjects in group II and none of the controls in group III. There was a statistically significant difference between group I and group II in serum ACPA level (<0.001), as well as between group I and group III (<0.001).
Conclusion
Our study shows an association between RA and chronic periodontitis. Individuals with RA are more likely to experience periodontitis.