Increased risk of periodontitis in patients with rheumatoid arthritis: A nationwide register study in Norway

Exploring the Bidirectional Relationship Between Periodontitis and Rheumatoid Arthritis in a Large Danish Cohort

OBJECTIVE

We investigated the bidirectional relationship between rheumatoid arthritis (RA) and periodontitis and their cross-sectional association using national administrative health care data.

METHODS

The sample included 3,308,903 individuals aged 20 to 79 years who resided in Denmark in 2000 and had remained free of RA and periodontitis in the previous 10 years. RA and periodontitis were defined using diagnosis and treatment codes. Marginal structural survival models were employed to estimate the effects of RA on periodontitis incidence and vice versa from 2000 to 2017. Using a cross-sectional sample of 2,574,536 individuals from 2017, the association of periodontitis with RA was investigated using regression analyses and probabilistic quantitative bias analyses, simulating RA and periodontitis misclassification and unmeasured confounding of smoking.

RESULTS

Between 2000 and 2017, 20,348 individuals developed RA and 740,799 developed periodontitis. The estimated hazard ratio (HR) for the effect of periodontitis on incident RA was 1.05 (95% confidence interval [CI] 0.88-1.25), resulting in a restricted mean survival time difference of one day. The HR for the effect of RA on incident periodontitis was 0.84 (95% CI 0.80-0.88), corresponding to a restricted mean survival time difference of 151 days. Cross-sectionally, the unadjusted prevalence ratio for the association was 1.15 (95% CI 1.11-1.19), whereas the estimate adjusted for measured and simulated confounding was practically null (0.99, 95% simulation interval 0.93-1.04).

CONCLUSION

These findings challenge previously reported bidirectional relationships between periodontitis and RA, pointing to potential residual confounding as an important link and prompting reconsideration of the biologic plausibility and clinical significance of these associations.

Neutrophil extracellular traps in rheumatoid arthritis and periodontitis: Contribution of PADI4 gene polymorphisms

AIM

We sought to investigate the release of neutrophil extracellular traps (NETs) in neutrophils from individuals with rheumatoid arthritis (RA) and controls and compare the presence of NETs in gingival tissues according to periodontal status. Also, the association between single nucleotide polymorphisms (SNPs) of the peptidyl arginine deaminase type 4 (PADI4) gene and the GTG haplotype with RA, periodontitis and NETs was evaluated in vitro.

MATERIALS AND METHODS

Peripheral neutrophils were isolated by density gradient, and NET concentration was determined by the PicoGreen method. Immunofluorescence was studied to identify NETs by co-localization of myeloperoxidase (MPO)-citrullinated histone H3 (H3Cit). Genotyping for SNPs (PADI4_89; PADI4_90; PADI4_92; and PADI4_104) was performed in 87 individuals with RA and 111 controls.

RESULTS

The release of NETs in vitro was significantly higher in individuals with RA and periodontitis and when stimulated with Porphyromonas gingivalis. Gingival tissues from subjects with RA and periodontitis revealed increased numbers of MPO-H3Cit-positive cells. Individuals with the GTG haplotype showed a higher release of NETs in vitro and worse periodontal parameters.

CONCLUSIONS

The release of NETs by circulating neutrophils is associated with RA and periodontitis and is influenced by the presence of the GTG haplotype.

Prevalence and Comorbidities Among Individuals With Rheumatoid Arthritis in the Saudi Arabian Context

BACKGROUND

 Rheumatoid arthritis (RA) in Saudi Arabia (SA) is a significant health concern with a notable impact on individuals and the healthcare system. This study aimed to investigate the prevalence and profile of comorbidities in patients with RA.

METHODOLOGY

 This is a retrospective descriptive study involving 150 RA patients from August 2022 to August 2023, which was conducted at Khamis Mushait General Hospital, a major healthcare institution in SA. We examined the medical records to gather pertinent information. Stata Statistical Software: Release 18 (2023; StataCorp LLC, College Station, Texas, United States) was used for data analysis. The examination focused on sociodemographic factors, disease duration, prescribed medications (including methotrexate and biologic therapy), and the presence of comorbidities. Approval for the study was obtained from the Institutional Review Board of the Aseer Ministry of Health (approval number: H-06-B-091).

RESULTS

 The study found a high prevalence of comorbidities in patients with RA. Around 96.7% of the patients had at least one documented comorbidity, highlighting this population's burden of additional health conditions. The most common comorbidity observed was anemia, affecting 48.7% of the patients. Other frequently observed comorbidities include hypertension, hyperlipidemia, diabetes mellitus, osteoporosis, interstitial lung disease, chronic renal disease, stroke, and coronary artery disease. The factors influencing comorbidities included an odds ratio of 1.086 (p=0.025), while being male was associated with lower odds (odds ratio=0.529, p=0.017). Additionally, disease duration (odds ratio=1.164, p=0.007), methotrexate use (odds ratio=2.553, p=0.001), and receiving biologic therapy (odds ratio=3.488, p<0.001) were significant contributors to comorbidities.

CONCLUSION

 These findings highlight the need for comprehensive approaches to address RA and its associated comorbidities. Research and awareness initiatives are essential to understand better the specific nuances of RA in SA, leading to improved diagnostic and treatment strategies for the needs of the local population.

Methotrexate and Non-Surgical Periodontal Treatment Change the Oral-Gut Microbiota in Rheumatoid Arthritis: A Prospective Cohort Study

This study evaluated the changes in the composition of oral-gut microbiota in patients with rheumatoid arthritis (RA) caused by methotrexate (MTX) and non-surgical periodontal treatment (NSPT). Assessments were performed at baseline (T0), 6 months after MTX treatment (T1), and 45 days after NSPT (T2). The composition of the oral and gut microbiota was assessed by amplifying the V4 region of the 16S gene from subgingival plaques and stools. The results of the analysis of continuous variables were presented descriptively and non-parametric tests and Spearman's correlation were adopted. A total of 37 patients (27 with periodontitis) were evaluated at T0; 32 patients (24 with periodontitis) at T1; and 28 patients (17 with periodontitis) at T2. MTX tended to reduce the alpha diversity of the oral-gut microbiota, while NSPT appeared to increase the number of different species of oral microbiota. MTX and NSPT influenced beta diversity in the oral microbiota. The relative abundance of oral microbiota was directly influenced by periodontal status. MTX did not affect the periodontal condition but modified the correlations that varied from weak to moderate (p < 0.05) between clinical parameters and the microbiota. MTX and NSPT directly affected the composition and richness of the oral-gut microbiota. However, MTX did not influence periodontal parameters.

Periodontitis in patients with primary Sjögren's syndrome: A nation-wide register study

The aim of this study was to compare the occurrence of periodontitis in patients with primary Sjögren's syndrome (pSS) and a non-Sjögren's patient group during a 7-year period from 2011 through 2017. In this population-based study, the patients were identified based on the International Classification of Diseases-10 (ICD-10) codes registered in the Norwegian Patient Registry (NPR), which contains information on diagnosis and time of admission for all hospitalized patients in Norway. The pSS group comprised patients with ≥4 registrations with ICD-10 code M35.0 (Sjögren's syndrome) as the main diagnosis. The dependent variable was periodontitis, defined by procedure codes registered in the Norwegian Control and Payment of Health Reimbursement (KUHR). Logistic regression analyses estimated the odds ratio for periodontitis in pSS patients relative to non-pSS patients, adjusted for relevant covariates. Lastly, regression analyses were performed separately for each of the 6 age categories. In total, 760 (7.5%) patients in the pSS group and 22,178 (7.1%) in the non-pSS group had periodontitis. When adjusting for covariates, the presence of pSS had no association with periodontitis (OR = 1.06, 95% CI: 0.98-1.14).