Does periodontitis represent a risk factor for rheumatoid arthritis? A systematic review and meta-analysis

Periodontal disease and sports performance: a systematic review and meta-analysis

This systematic review and meta-analysis aimed to assess the association between athletic performance and periodontal disease (PD). Observational studies published up to April 2022 were searched in online databases (PubMed, Scopus, Web of Science, The Cochrane Library, LILACS, OpenGrey, and Google Scholar). PECO statement focused on studies with professional athletes (Participants) with PD (Exposition) compared to those with healthy periodontium (Comparison) and its effects on sports performance (outcome). Searches were conducted according to the PRISMA guidelines (registration protocol: 10.17605/OSF.IO/7ADH6) and risk of bias evaluation according to the Joanna Briggs Institute checklist. A total of 793 references were retrieved, of which eight were considered eligible. Two studies did not show an association between clinical PD parameters and performance. A meta-analysis with 396 participants suggested a relationship between PD and self-reported reduction in sports performance (odds ratio [OR] = 1.55; 95% confidence interval [CI] 1.04-2.31; p = 0.03; I2 = 0%) with moderate quality of evidence accordingly GRADE analysis. Despite the differences in performance evaluations between studies, PD was associated with reduced self-reported sports performance. Additional studies assessing confounding factors and objective assessment of PD and performance are needed to clarify the real effect of both conditions.

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.

Periodontitis and periodontopathic bacteria as risk factors for rheumatoid arthritis: A review of the last 10 years

Rheumatoid arthritis (RA) is characterized by chronic inflammatory destruction of joint tissue and is caused by an abnormal autoimmune response triggered by interactions between genetics, environmental factors, and epigenetic and posttranslational modifications. RA has been suggested to be interrelated with periodontitis, a serious form or stage of chronic inflammatory periodontal disease associated with periodontopathic bacterial infections, genetic predisposition, environmental factors, and epigenetic influences. Over the last decade, a number of animal and clinical studies have been conducted to assess whether or not periodontitis and associated periodontopathic bacteria constitute risk factors for RA. The present review introduces recent accumulating evidence to support the associations of periodontitis and periodontopathic bacteria with the risk of RA or the outcome of RA pharmacological treatment with disease-modifying antirheumatic drugs. In addition, the results from intervention studies have suggested an improvement in RA clinical parameters after nonsurgical periodontal treatment. Furthermore, the potential causal mechanisms underlying the link between periodontitis and periodontopathic bacteria and RA are summarized.

Systemic immune-inflammation index in patients with generalized stage III grade C periodontitis

OBJECTIVES

Systemic immune-inflammation index (SII) is a novel, inflammatory biomarker whose role in predicting several chronic systemic diseases has been recently identified. However, its association with generalized stage III grade C periodontitis in young adults remains unknown.

MATERIAL AND METHODS

The study is a multicentered, double-blind, hospital-based case-control clinical study. Periodontal examination comprised of recording plaque index, sites with bleeding on probing, pocket depth and clinical attachment loss for patients with generalized stage III grade C periodontitis and periodontally healthy group. Complete blood counts were obtained and used for calculating SII, neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio. Collected data were then subjected to statistical analyses.

RESULTS

SII was significantly higher in patients with generalized stage III grade C periodontitis compared to periodontally healthy individuals (723.87 vs. 537.74 × 109 /L, p < 0.0001). SII is associated with severe periodontitis in young adults (odds ratio [OR]:11.86, 95% CI 9.61-20.76, p < 0.0001) after adjusting for factors found significant in univariate analysis. Receiver operative curve analysis demonstrated a fair predictive validity of SII in detecting generalized stage III grade C periodontitis in young adults (AUC: 0.766, 95%CI 0.731-0.799, p < 0.0001, sensitivity 81.27%, specificity 76.50% and diagnostic accuracy 78.89%). SII did not exhibit superior predictive validity when compared with NLR in the context of generalized stage III grade C periodontitis (AUC for SII: 0.766, 95%CI 0.731-0.799, AUC for NLR: 0.788, 95% CI 0.754-0.819; p = 0.28).

CONCLUSION

SII is associated with generalized stage III grade C periodontitis in young adults.

Periodontitis and risk of immune-mediated systemic conditions: A systematic review and meta-analysis

INTRODUCTION

The aim of this review is to examine and quantify the long-term risk of immune-mediated systemic conditions in people with periodontitis compared to people without periodontitis.

METHODS

Medline, EMBASE and Cochrane databases were searched up to June 2022 using keywords and MeSH headings. The 'Risk of Bias in Non-Randomised Studies of Interventions' tool was used to assess bias. Cohort studies comparing incident metabolic/autoimmune/inflammatory diseases in periodontitis to healthy controls were included. Meta-analysis and meta-regression quantified risks and showed impact of periodontitis diagnosis type and severity.

RESULTS

The search retrieved 3354 studies; 166 studies were eligible for full-text screening, and 30 studies were included for review. Twenty-seven studies were eligible for meta-analysis. The risks of diabetes, rheumatoid arthritis (RA) and osteoporosis were increased in people with periodontitis compared to without periodontitis (diabetes-relative risk [RR]: 1.22, 95% CI: 1.13-1.33; RA-RR: 1.27, 95% CI: 1.07-1.52; osteoporosis-RR: 1.40, 95% CI: 1.12-1.75). Risk of diabetes showed gradient increase by periodontitis severity (moderate-RR = 1.20, 95% CI = 1.11-1.31; severe-RR = 1.34, 95% CI = 1.10-1.63).

CONCLUSION

People with moderate-to-severe cases of periodontitis have the highest risk of developing diabetes, while the effect of periodontal severity on risk of other immune-mediated systemic conditions requires further investigation. More homologous evidence is required to form robust conclusions regarding periodontitis-multimorbidity associations.

Effects of periodontitis on cancer outcomes in the era of immunotherapy

Periodontitis results from dysbiosis of the oral microbiome and affects up to 70% of US adults aged 65 years and older. More than 50 systemic inflammatory disorders and comorbidities are associated with periodontitis, many of which overlap with immunotherapy-associated toxicities. Despite the increasing use of immunotherapy for the treatment of cancer, uncertainty remains as to whether the microbial shift associated with periodontal disease can influence response rates and tolerance to cancer immunotherapy. We herein review the pathophysiology of periodontitis and the local and systemic inflammatory conditions related to oral dysbiosis, and discuss the overlapping adverse profiles of periodontitis and immunotherapy. The effects of the presence of Porphyromonas gingivalis, a key pathogen in periodontitis, highlight how the oral microbiome can affect the hosts' systemic immune responses, and further research into the local and systemic influence of other microorganisms causing periodontal disease is necessary. Addressing periodontitis in an ageing population of people with cancer could have potential implications for the clinical response to (and tolerability of) immunotherapy and warrants further investigation.

Lack of association between periodontitis and rheumatoid arthritis

BACKGROUND AND OBJECTIVE

Periodontitis and rheumatoid arthritis (RA) have been associated in a bidirectional way. The objective of this study was to determine the association between clinical parameters of periodontitis and RA.

MATERIALS AND METHODS

Seventy-five (75) participants distributed in 3 groups (21 patients with periodontitis without RA, 33 patients with periodontitis with RA and 21 patients with reduced periodontium with RA) were included in this cross-sectional study. A full periodontal and medical examination was performed in each patient. Additionally, subgingival plaque samples for the detection of Porphyromonas gingivalis (P. gingivalis) and blood samples for biochemical markers of RA were also taken. Logistic regression analysis adjusted for confounding variables, Spearman's rank correlation coefficient and a linear multivariate regression were used to analyze the data.

RESULTS

Patients with RA presented less severity of periodontal parameters. The highest levels of anti-citrullinated protein antibodies were detected in non-periodontitis patients with RA. Covariates such as age, P. gingivalis, diabetes, smoking, osteoporosis and use of medication were not associated with RA. All periodontal variables and P. gingivalis expressed a negative correlation with biochemical markers of RA (P<0.05).

CONCLUSIONS

Periodontitis was not associated with RA. Furthermore, there was no correlation between periodontal clinical parameters and biochemical markers of RA.

Evolving evidence for relationships between periodontitis and systemic diseases: Position paper from the Canadian Dental Hygienists Association

AIM

The aim of this position paper is to investigate the current state of the evidence for proposed associations between periodontitis and rheumatoid arthritis, Alzheimer's disease, obesity, inflammatory cancers, and renal disease using a narrative review approach. This is the last of a series of 5 position papers from the Canadian Dental Hygienists Association (CDHA) on the relationship between periodontitis and systemic conditions.

METHODS

Individual literature searches were conducted for each of the 5 proposed linkages and limited to human studies, with a preference for systematic reviews (SRs) and prospective studies, in the English language, published between 2015 and 2021, focused on associations between 1) periodontitis and rheumatoid arthritis; 2) periodontitis and Alzheimer's disease/cognitive impairment; 3) periodontitis and obesity; 4) periodontitis and inflammatory cancers; and 5) periodontitis and chronic kidney disease. Databases searched were PubMed, MEDLINE/OVID, CINAHL, Scopus, Cochrane Registry of Systematic Reviews, and Web of Science.

RESULTS

A total of 39 papers were selected for discussion, including 6 SRs for rheumatoid arthritis; 7 SRs for Alzheimer's disease/cognitive impairment; 11 SRs, 1 meta-review of SRs, and 1 population-based cohort study for obesity; 9 SRs for inflammatory cancers; and 4 SRs for kidney disease.

CONCLUSIONS

The evidence for the 5 proposed associations varied in strength, with obesity being most strongly associated with periodontal disease. More robust studies are recommended to clarify the exact nature of these associations.

Epidemiology of rheumatoid arthritis: genetic and environmental influences

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic systemic disease characterized by articular involvement and extra-articular manifestations. The incidence and prevalence of the disease vary across populations, and there is an ongoing debate on whether a change of RA occurrence over time exists or is due to methodological issues and other biases. Moreover, the disease's onset is related to an interaction of genetic and environmental factors that influence its expression.

AREAS COVERED

This review explores the latest knowledge on RA epidemiology and the possible risk factors associated with its presentation to identify potential warning signs that may in the future help disease management.

EXPERT OPINION

Current epidemiological evidence suggests a significant impact of smoking, sex hormones, and lifestyle status in RA occurrence. However, the association between these variables has not yet been thoroughly studied. Still, their effect must be interpreted as they may present subsequently integral indicators for a more rational approach of the disease.

Does periodontal treatment improve rheumatoid arthritis disease activity? A systematic review

Objectives

The association of periodontal disease in people diagnosed with RA is emerging as an important driver of the RA autoimmune response. Screening for and treating periodontal disease might benefit people with RA. We performed a systematic literature review to investigate the effect of periodontal treatment on RA disease activity.

Methods

Medline/PubMed, Embase and Cochrane databases were searched. Studies investigating the effect of periodontal treatment on various RA disease activity measures were included. The quality of included studies was assessed. Data were grouped and analysed according to RA disease outcome measures, and a narrative synthesis was performed.

Results

We identified a total of 21 studies, of which 11 were of non-randomized experimental design trials and 10 were randomized controlled trials. The quality of the studies ranged from low to serious/critical levels of bias. RA DAS-28 was the primary outcome for most studies. A total of 9 out of 17 studies reported a significant intra-group change in DAS-28. Three studies demonstrated a significant intra-group improvement in ACPA level after non-surgical periodontal treatment. Other RA biomarkers showed high levels of variability at baseline and after periodontal treatment.

Conclusion

There is some evidence to suggest that periodontal treatment improves RA disease activity in the short term, as measured by DAS-28. Further high-quality studies with longer durations of follow-up are needed. The selection of the study population, periodontal interventions, biomarkers and outcome measures should all be considered when designing future studies. There is a need for well-balanced subject groups with prespecified disease characteristics.

P. G, Rahman W. Clinical and diagnostic significance of blood leukocyte ratios in young patients with stage III grade C periodontitis

OBJECTIVES

Blood leukocyte ratios have been recently proposed as simple, rapid, cheap and easily accessible biomarkers of systemic inflammation. However, little is known about the relationship of neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and lymphocyte-monocyte ratio (LMR) with periodontitis, which might not only serve as the potential biomarkers of systemic inflammation but also aid in diagnosis/screening of severe periodontitis. Hence, the purpose of this study was to evaluate the differences in the serum levels of these leukocyte ratios in healthy subjects and patients with generalized stage III Grade C periodontitis, and their applicability in identifying patients with the risk of developing severe periodontitis.

MATERIAL AND METHODS

The subjects were categorized into case and control group. Clinical parameters including Plaque index (PI), modified Gingival Index (mGI), Mean ratio of bleeding sites, Probing Pocket depth (PPD) and the clinical attachment loss (CAL) were assessed in both the groups. Venous blood samples were collected from subjects from both groups for the biochemical analysis and blood leukocyte ratios- NLR, PLR and LMR were calculated. The values were then subjected to statistical analysis.

RESULTS

The results showed significantly higher NLR and lower LMR values in patients with generalized stage III grade C periodontitis. Both the blood leukocyte ratios were moderately associated with increasing clinical parameters of periodontal disease. However, the values of PLR, although found to be higher in the periodontitis group, did not make a significant difference when compared with periodontally healthy subjects. The cut-off value of >2.15 for NLR and <7.16 for LMR fairly predicted the risk of severe periodontitis in young adults.

CONCLUSIONS

NLR and LMR can provide a new insight into the relationship between periodontitis and systemic diseases and can be of potential diagnostic value in identifying patients with severe periodontitis of younger age group.

Antimicrobial Activity of Eucalyptus globulus, Azadirachta indica, Glycyrrhiza glabra, Rheum palmatum Extracts and Rhein against Porphyromonas gingivalis

Novel plant-derived antimicrobials are of interest in dentistry, especially in the treatment of periodontitis, since the use of established substances is associated with side effects and concerns of antimicrobial resistance have been raised. Thus, the present study was performed to quantify the antimicrobial efficacy of crude plant extracts against Porphyromonas gingivalis, a pathogen associated with periodontitis. The minimal inhibitory concentrations (MICs) of Eucalyptus globulus leaf, Azadirachta indica leaf, Glycyrrhiza glabra root and Rheum palmatum root extracts were determined by broth microdilution for P. gingivalis ATCC 33277 according to CLSI (Clinical and Laboratory Standards Institute). The MICs for the E. globulus, A. indica and G. glabra extracts ranged from 64 mg/L to 1024 mg/L. The lowest MIC was determined for an ethanolic R. palmatum extract with 4 mg/L. The MIC for the anthraquinone rhein was also measured, as the antimicrobial activity of P. palmatum root extracts can be partially traced back to rhein. Rhein showed a remarkably low MIC of 0.125 mg/L. However, the major compounds of the R. palmatum root extract were not further separated and purified. In conclusion, R. palmatum root extracts should be further studied for the treatment of periodontitis.

Effects of Obesity on Bone Healing in Rats

Although the association between periodontitis and obesity is well explored, it is unclear whether obesity is associated with a worse therapeutic outcome after periodontal treatment. The aim of this study was to investigate the effects of obesity on bone healing with and without the application of regeneration-promoting molecules. A standardized bone fenestration-type defect was created over the root of the mandibular first molar in 15 Wistar rats. Ten animals received a high-fat, high-sucrose diet (HFSD), while the remaining five animals were fed a standard diet. During surgery, the fenestration defects from half of the HFSD-fed, i.e., obese animals, were treated with regeneration-promoting molecules (enamel matrix derivative; EMD). After four weeks, bone healing was evaluated by histomorphometry, TRAP staining and immunohistochemistry for RUNX2 and osteopontin. The analyses revealed that the spontaneous healing of the periodontal defects was compromised by obesity. Application of EMD partially compensated for the negative effect of obesity. Nevertheless, EMD-stimulated bone healing in obese animals was not better than the spontaneous healing in the obesity-free control group, indicating that obesity may also inhibit the stimulatory effects of regeneration-promoting molecules. Our results show that obesity can negatively influence bone healing and suggest that bone healing may be compromised in humans.

Similarity and Potential Relation Between Periimplantitis and Rheumatoid Arthritis on Transcriptomic Level: Results of a Bioinformatics Study

Background

This bioinformatics study aimed to reveal potential cross-talk genes, related pathways, and transcription factors between periimplantitis and rheumatoid arthritis (RA).

Methods

The datasets GSE33774 (seven periimplantitis and eight control samples) and GSE106090 (six periimplantitis and six control samples) were included from the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus (GEO). A differential expression analysis (p < 0.05 and |logFC (fold change)| ≥ 1) and a functional enrichment analysis (p < 0.05) were performed. Based on this, a protein-protein interaction (PPI) network was constructed by Cytoscape. RA-related genes were extracted from DisGeNET database, and an overlap between periimplantitis-related genes and these RA-related genes was examined to identify potential cross-talk genes. Gene expression was merged between two datasets, and feature selection was performed by Recursive Feature Elimination (RFE) algorithm. For the feature selection cross-talk genes, support vector machine (SVM) models were constructed. The expression of these feature genes was determined from GSE93272 for RA. Finally, a network including cross-talk genes, related pathways, and transcription factors was constructed.

Results

Periimplantitis datasets included 138 common differentially expressed genes (DEGs) including 101 up- and 37 downregulated DEGs. The PPI interwork of periimplantitis comprised 1,818 nodes and 2,517 edges. The RFE method selected six features, i.e., MERTK, CD14, MAPT, CCR1, C3AR1, and FCGR2B, which had the highest prediction. Out of these feature genes, CD14 and FCGR2B were most highly expressed in periimplantitis and RA. The final activated pathway-gene network contained 181 nodes and 360 edges. Nuclear factor (NF) kappa B signaling pathway and osteoclast differentiation were identified as potentially relevant pathways.

Conclusions

This current study revealed FCGR2B and CD14 as the most relevant potential cross-talk genes between RA and periimplantitis, which suggests a similarity between RA and periimplantitis and can serve as a theoretical basis for future research.

Should We Be Screening for and Treating Periodontal Disease in Individuals Who Are at Risk of Rheumatoid Arthritis?

There is increasing evidence supporting an association between periodontal disease (PD) and rheumatoid arthritis (RA), both mechanistically and clinically. Trials have shown that treating PD in people with RA may improve RA disease activity. Patients with musculoskeletal symptoms without arthritis, who test positive for cyclic-citrullinated protein antibodies, are at risk of RA (CCP+ at-risk), with seropositivity preceding arthritis onset by months or years. Importantly, there is evidence to suggest that periodontal inflammation may precede joint inflammation in CCP+ at-risk and, therefore, this could be a trigger for RA. There has been increased research interest in RA prevention and the phenotyping of the pre-RA disease phase. This review will examine the merits of identifying individuals who are CCP+ at-risk and performing screening for PD. In addition, we discuss how PD should be treated once identified. Finally, the review will consider future research needed to advance our understanding of this disease association.

No Obvious Role for Suspicious Oral Pathogens in Arthritis Development

A particular role for Porphyromonas gingivalis (Pg) and Aggregatibacter actinomycetemcomitans (Aa) has been suggested in periodontitis and rheumatoid arthritis (RA), as these bacteria could initiate the formation of rheumatoid factor (RF) and anticitrullinated protein autoantibodies (ACPA). We assessed whether serum antibodies against Pg and Aa in RA patients and non-RA controls reflect the subgingival presence of Pg and Aa, and evaluated the relationship of these antibodies to the severity of periodontal inflammation and RA-specific serum autoantibodies. In 70 Indonesian RA patients and 70 non-RA controls, the subgingival presence of Pg and Aa was assessed by bacterial 16S rRNA gene sequencing, and serum IgG levels specific for Pg and Aa were determined. In parallel, serum levels of ACPA (ACPA:IgG,IgA) and RF (RF:IgM,IgA) were measured. The extent of periodontal inflammation was assessed by the periodontal inflamed surface area. In both RA patients and the controls, the presence of subgingival Pg and Aa was comparable, anti-Pg and anti-Aa antibody levels were associated with the subgingival presence of Pg and Aa, and anti-Pg did not correlate with ACPA or RF levels. The subgingival Pg and Aa were not related to RA. No noteworthy correlation was detected between the antibodies against Pg and Aa, and RA-specific autoantibodies.

Effects of non-surgical periodontal therapy on periodontal clinical data in periodontitis patients with rheumatoid arthritis: a meta-analysis

Backgrounds

To date, there is still no consensus about the clinical efficacy of non-surgical periodontal therapy in rheumatoid arthritis (RA) patients with periodontitis. Therefore, the aim of this study was to summarize clinical data regarding the efficacy of scaling and root planing (SRP) in patients with RA and periodontitis compared to non-RA periodontitis patients.

Methods

We selected randomized controlled trials (RCTs) that compared periodontal clinical data in RA as compared to non-RA periodontitis patients by searching Embase, PubMed and Cochrane Central Register of Controlled Trials and by manually retrieving from the earliest records to March 8, 2021. The overall effect size of plaque index (PI), gingival index (GI), attachment loss (AL), probing depth (PD) and bleeding on probing (BOP) were calculated by either a fixed or random-effect model, and subgroup analyses were conducted according to the different time points of follow-up. Two investigators extracted the data and assess the accuracy of the obtained results with 95% of Confidence Intervals (CI). Cochrane Collaboration's tool was responsible for the evaluation of the literature quality and the inter-study heterogeneity was evaluated by Q test and I² statistic. Sensitivity analyses were applied for results with heterogeneity. Publication bias was determined by Begg's test, Egger's test and the trim-and-fill method.

Results

Seven RCTs including 212 patients eventually met the inclusion criteria for the study. As the primary results, the change of PD was not statistically significant and in the secondary results changes of PI, GI, AL and BOP were also not statistically significant in RA patients with periodontitis compared to non-RA periodontitis patients. In subgroup analysis, a larger BOP reduction at 3 months, PI and AL reduction at 6 months were observed in patients with RA and periodontitis group. The results of sensitivity analyses had no significant effect. No evidence of potential publication bias was tested. There were some limitations due to the small number of eligible RCTs.

Conclusions

SRP is equally effective in RA as compared to non-RA periodontitis patients. It suggests RA does not affect the clinical efficacy of non-surgical periodontal therapy. These results could serve evidence-based practice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01695-w.

Tooth Loss Is Associated with Disease-Related Parameters in Patients with Rheumatoid Arthritis and Ankylosing Spondylitis-A Cross-Sectional Study

Background: The aim of this cross-sectional study was to investigate potential associations between periodontal inflamed surface area (PISA) and tooth loss with disease-related parameters in patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Methods: Patients who attended the Department of Nephrology and Rheumatology, University Medical Centre Goettingen, Germany, were included. The oral examination comprised the detection of the number of remaining teeth and periodontal condition based on staging and grading matrix. Based on periodontal pockets with positive bleeding on probing, the periodontal inflamed surface area (PISA) was determined. Disease related parameters were extracted from the patients’ records. Results: In total, 101 (RA) and 32 participants (AS) were included. Patients with RA had 22.85 ± 4.26 and AS patients 24.34 ± 5.47 remaining teeth (p < 0.01). Periodontitis stage III and IV was present in 91% (RA) and 81.2% (AS) of patients (p = 0.04). Associations between PISA and disease-related parameters were not found in both groups (p > 0.05). In RA, a higher age (p < 0.01), C-reactive protein (p = 0.02), disease activity (p < 0.01) and prednisolone intake (p < 0.01) were associated with fewer remaining teeth. In AS, a higher age (p = 0.02) and increased Bath Ankylosing Spondylitis Metrology Index (p = 0.02) were associated with a lower number of remaining teeth. Conclusions: Tooth loss is associated with disease activity, especially in RA individuals. Dental care to prevent tooth loss might be recommendable to positively influence oral health condition and disease activity in RA and SA patients.

Lead exposure and its association with neurological damage: systematic review and meta-analysis

Lead (Pb) is one of the most toxic and abundant elements in the earth's crust, which is pointed out that the intoxication caused by it may damage biological systems. This systematic review with meta-analysis aimed to evaluate the association between Pb exposure and neurological damage. This work was executed according to PRISMA guidelines, and seven online databases were consulted. Based on the PECO strategy, studies presenting humans as participants (populations) exposed to Pb (exposure) compared to non-exposed to Pb (control) evaluating the neurological impairment (outcome) were included. The quality and risk of bias were verified by Fowkes and Fulton checklist. Two meta-analyses were conducted considering Digit Symbol and Profile Mood tests. The certainty of the evidence was evaluated with the GRADE tool. This review identified 2019 studies, of which 12 were eligible according to the inclusion criteria. Eight were considered with a low risk of bias. All the studies elected showed that exposure to Pb is associated with neurological damage, but the meta-analysis did not show any difference for the evaluated tests, and the certainty of the evidence was considered very low. Nevertheless, the included studies showed that Pb occupational exposure is associated with neurological damage, and the main parameters evaluated for possible neurological damage were related to mnemonic aspects, reaction time, intelligence, attention disorders, and mood changes. Thus, our results revealed that a definitive demonstration of an association of Pb and neurological changes in humans is still a pending issue. Future studies should take into consideration more confident methods to answer this question.

Periodontal disease in seropositive rheumatoid arthritis: scoping review of the epidemiological evidence

The link between periodontal disease (PD) and rheumatoid arthritis (RA) has been hypothesized to lie in the anti-cyclic citrullinated protein antibody (ACPA) molecules present in seropositive RA. This review aimed to discuss how RA and specifically ACPA-positive RA link to PD, and appraise the epidemiological evidence on the relationship between ACPA-positive RA and PD. Articles were searched following the PRISMA guideline across the MEDLINE, Web of Science, Scopus and Cochrane Library databases. A total of 21 articles met the inclusion criteria of reporting the epidemiological data on the different ACPA status of the subjects with RA and PD (or periodontitis) parameters. A discrepancy is noted in the epidemiological evidence on the difference in the prevalence and severity of PD between ACPA-positive and ACPA-negative RA patients. Although the link between RA and PD is mostly discussed in terms of ACPA, reports on the different manifestations of PD between the two RA subsets remains inconclusive.

Challenges and Opportunities of Targeted Behavioral Interventions for Groups at Risk for Developing Rheumatoid Arthritis

Background: Rheumatoid arthritis (RA) is a serious autoimmune disease which causes painful, swollen joints and can impact quality of life and increase morbidity and mortality. There are several preclinical stages of RA that correspond to at-risk groups that include: genetic risk, risk from behaviors, elevation of RA-related autoantibodies, and early clinical disease manifestations such as undifferentiated arthritis. Early interventions are crucial to slowing progression to and potentially preventing RA onset. Modification of behaviors among at-risk individuals may decrease RA risk. There are several challenges and opportunities in implementing preventative behavioral interventions, which may vary within different at-risk groups. Methods: We performed a narrative review of the literature, including meta-analyses focused on RA risk-related behaviors as well as publications investigating the potential efficacy of behavioral modifications on RA risk. Results: There are multiple behavioral risk factors associated with RA, including smoking, obesity, low physical activity, low quality diet, and poor dental hygiene, which may contribute to progression to clinical RA. Meta-analyses have been performed for smoking, excess body weight, and physical activity. Likelihood of adopting behavioral modifications may increase as RA risk increases. Conclusions: Clinicians may be able to tailor preventative approaches to various RA at-risk groups to help reduce RA risk, but further research is needed. A better understanding of the relationship of behaviors with RA risk and optimized approaches to implementing behavioral changes may allow for clinicians to tailor their preventative approaches for at-risk individuals.

Rheumatic diseases in Africa

Historically, rheumatic diseases have not received much attention in Africa, particularly in sub-Saharan Africa, possibly owing to a focus on the overwhelming incidence of infectious diseases and the decreased life span of the general population in this region. Global attention and support, together with better health policies and planning, have improved outcomes for many infectious diseases; thus, increasing attention is being turned to chronic non-communicable diseases. Rheumatic diseases were previously considered to be rare among Africans but there is now a growing interest in these conditions, particularly as the number of rheumatologists on the continent increases. This interest has resulted in a growing number of publications from Africa on the more commonly encountered rheumatic diseases, as well as case reports of rare diseases. Despite the limited amount of available data, some aspects of the epidemiology, genetics and clinical and laboratory features of rheumatic diseases in African populations are known, as is some detail on the use of therapeutics. Similarities and differences in these conditions can be seen across the multi-ethnic and genetically diverse African continent, and it is hoped that increased awareness of rheumatic diseases in Africa will lead to earlier diagnosis and better outcomes for patients.

The prevalence of rheumatic diseases is increasing in African countries, leading to an increased need for specialist rheumatologists and disease-modifying drugs. In this Review, the authors outline what is currently known about the state of rheumatic diseases in Africa.

In the past, there has been an emphasis on communicable diseases in Africa, but attention has now shifted towards non-communicable diseases such as rheumatic diseases.

Common rheumatic diseases are seen in Africa and are both comparable and different from presentations seen outside of Africa.

Diverse genetic and environmental factors affect the presentation of common rheumatic diseases among different African nations.

A shortage of appropriately trained staff, laboratory testing capacity and effective medications exists across the whole continent.

Advocacy and research are needed to increase awareness of the risk factors, presentations and management of rheumatic diseases in Africa.

Specialized treatment guidelines are needed for resource-poor countries in Africa.

Rheumatoid arthritis associated with the occurrence, severity and extension of periodontitis: A case-control study

Background

Emerging evidence pointed to a potential association between periodontitis (PE) and rheumatoid arthritis (RA), based on shared characteristics and similarities in risk factors, immunogenetics and pathways of tissue destruction. The aim of this study was to evaluate the potential association between RA and PE, as well as the influence of risk variables in this association.

Material and Methods

The present case-control study comprised 471 individuals (157 cases with RA and 314 controls) that underwent a full-mouth periodontal examination. The association between risk variables and the occurrence of AR and PE were evaluated through univariate and multivariate logistic analysis.

Results

Higher frequency (p<0.001), severity (p=0.006) and extension (p=0.018) of PE was observed among the cases when compared to controls. Variables retained in the final multivariate models for the occurrence of PE were: lower number of teeth, smoking, no use of dental floss, ≥4 daily toothbrushing and RA; for the occurrence of RA were: higher age, female gender, smoking, alcohol use and PE. It is important to stress that RA (OR=2.53; 95%CI 1.24-3.86; p<0.001) was retained in the model for PE, and PE (OR=3.12; 95%CI 1.47-4.26; p<0.001) was retained in the model for RA.

Conclusions

The present study demonstrated a high frequency of PE among individuals with RA and an important association among the occurrence, severity and extension of PE and RA and smoking. Key words:Case-control study, risk factors, periodontitis, rheumatoid arthritis.

Comparative Analysis of Cytokine Expression in Oral Keratinocytes and THP-1 Macrophages in Response to the Most Prevalent Serotypes of Aggregatibacter actinomycetemcomitans

BACKGROUND

Periodontitis is a chronic inflammatory disease associated with a dysbiotic biofilm. Many pathogens have been related with its progression and severity, one of which is Aggregatibacter actinomycetemcomitans, a Gram-negative bacteria with seven serotypes (a-g) according with the structure of its LPS, with serotype b defined as the most virulent compared with the other serotypes. The aim of this study was to evaluate the response of oral keratinocytes and macrophages to A. actinomycetemcomitans.

METHODS

Oral keratinocytes (OKF6/TERT2) and macrophages (THP-1) were infected with A. actinomycetemcomitans serotypes a, b and c. The expression of IL-1β, IL-6, IL-8, IL-18, TNF-α, MMP-9, RANKL, TLR-2, TLR-4, TLR-6, thymic stromal lymphopoietin (TSLP), and ICAM-1 was evaluated by qPCR at 2 and 24 h after infection.

RESULTS

An increase in the expression of these molecules was induced by all serotypes at both times of infection, with macrophages showing higher levels of expression at 24 h compared to epithelial cells in which the highest levels were observed in the first hours after infection.

CONCLUSIONS

Keratinocytes and macrophages contribute to the inflammation in periodontitis from the early stages of infection, producing the first waves of cytokines, acting as the first signal for professional immune cell recruitment and modulation of more specific immune responses.

Exploring the Role of Interleukin-6 Receptor Inhibitor Tocilizumab in Patients with Active Rheumatoid Arthritis and Periodontal Disease

BACKGROUND

The aim of our study was to explore the influence of weekly subcutaneous administration of interleukin-6 (IL-6) receptor inhibitor tocilizumab (TCZ) on periodontal status in a local longitudinal study of patients with rheumatoid arthritis (RA) and periodontal disease (PD).

METHODS

We performed a 6-month prospective study in 51 patients with chronic periodontitis and moderate-to-severe RA starting TCZ in accordance with local recommendations. Extensive rheumatologic (clinical activity, inflammatory, serological biomarkers) and periodontal (visible plaque index, gingival index, bleeding on probing, probing pocket depth, clinical attachment loss) assessments were done. Changes in RA activity and periodontal status were reassessed after 3 and 6 months.

RESULTS

We demonstrated significant correlations between periodontal status, disease activity, and serologic biomarkers (p < 0.05). Tocilizumab significantly improved the gingival index scores and decreased the number of sites with bleeding on probing after only 3 months (p < 0.05), while the probing pocket depth significantly decreased after 6 months; overall, clinical attachment loss presented only slight changes without any statistical significance as well as teeth count and plaque levels (p > 0.05).

CONCLUSION

IL-6 inhibition is able to improve periodontal outcomes in patients with RA and concomitant PD, which is essentially related to a dramatic decrease in serum inflammatory mediators.

Association of periodontitis and tooth loss with liver cancer: A systematic review

A number of epidemiological studies have suggested a positive association between periodontal diseases and oro-digestive cancers, including liver cancer. The purpose of the present systematic review was to analyze the current evidence regarding the potential association between periodontitis and/or tooth loss and the risk of liver cancer. A comprehensive search of PubMed, Scopus and Web of Science databases was conducted in August 2019. The inclusion criteria comprised all observational studies that assessed the relationship between periodontitis or tooth loss and liver cancer. Case reports, animal studies, experimental studies, and reviews were excluded. Due to great heterogeneity among the included studies, no meta-analysis was conducted. Six studies (five prospective cohorts and one case-control) comprising 619,834 subjects (including 916 liver cancer cases) were included. The studies were conducted in the United States, Europe, and Asia. Three large-scale cohort studies reported a positive association between periodontitis or tooth loss and the risk of liver cancer. One case-control study found some association between liver cancer and loss of 12-23 teeth, but such association was not replicated in patients with greater number of tooth loss. Contrarily, two studies failed to report any association between periodontitis and/or tooth loss and the risk of liver cancer. The available evidence suggests a possible link between tooth loss/periodontitis and the risk of liver cancer. However, the evidence is not conclusive enough, a fact that drives to conduct more, well-designed, prospective cohort studies to further explore the potential association between periodontitis and the risk of liver cancer.

Association Between Diabetic Retinopathy and Periodontitis-A Systematic Review

Background: Diabetic retinopathy is a common microvascular complication in diabetic patients and is considered the main cause of visual loss worldwide. Periodontitis is a chronic inflammatory condition, which compromises dental supporting tissues. The chronic bacterial challenge in periodontitis is a persistent source of inflammatory mediators that may be associated with insulin resistance, increasing the risk of complications of diabetes mellitus. This systematic review aimed to summarize the evidence in the association between diabetic retinopathy and periodontitis. Methods: This review was registered under the number CRD 42019142267. A search strategy in five electronic databases and a gray literature source was performed based on the PECO acronym. After data extraction, the qualitative synthesis and risk of bias analyses were performed using the Newcastle-Ottawa scale. The level of evidence of all studies taken together was evaluated through the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Results: Out of the 253 citations screened, five cross-sectional studies met the eligibility criteria and were included in the qualitative analysis, in which two were judged to be of good quality, one as fair quality, and two as poor quality. Among the included studies, a significant relationship between the severity of periodontitis (CAL > 5 mm) and the severity of diabetic retinopathy (p < 0.05) was reported by four studies. Also, an association between both diseases in non-obese adults was found after adjustments [OR 2.206 (1.114-4.366); p = 0.0232). However, the analysis of evidence by GRADE assessment was rated as low. Conclusions: Although the results of individual studies suggest an association between diabetic retinopathy and periodontitis, the quality of the body of evidence was judged to be low by the GRADE approach. Further studies with larger sample sizes, adequate models of cofounders' adjustments, and prospective analysis of periodontitis and diabetes conditions ought to be conducted to clarify this association.

Causal association between periodontitis and risk of rheumatoid arthritis and systemic lupus erythematosus: a Mendelian randomization

OBJECTIVE

To investigate whether periodontitis is causally associated with risk of rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE).

METHODS

We performed two-sample Mendelian randomization (MR) analysis using the inverse variance-weighted (IVW), weighted median, and MR-Egger regression methods on publicly available summary statistics datasets using a periodontitis genome-wide association study (GWAS) as an exposure and RA and SLE GWASs on individuals of European descent as outcomes.

RESULTS

We selected 7 or 20 single-nucleotide polymorphisms from a periodontitis GWAS as instrumental variables for RA or SLE. The IVW method results support a causal association between periodontitis and RA (beta = 0.168, SE = 0.080, p = 0.035) and SLE (beta = 0.0001, SE = 0.0001, p = 0.046) risk; however, the weighted median approach did not indicate a significant causal association. MR-Egger regression revealed that directional pleiotropy was unlikely to be biasing the RA (intercept = -0.115, p = 0.078) or SLE results (intercept = 4.68E-05, p = 0.394); no significant causal association was found between periodontitis and RA and SLE. The MR estimates from the IVW, weighted median, and MR-Egger regression analyses were not consistent.

CONCLUSION

Only the results of MR analysis by the IVW method indicated that periodontitis is likely causally associated with an increased risk of RA and SLE incidence. Our MR showed weak causal association between periodontitis and RA or SLE. These findings may assist in elucidating the underlying mechanisms of the effects of periodontitis on RA and SLE incidence.

Porphyromonas gingivalis and Its Systemic Impact: Current Status

The relationship between periodontitis and systemic diseases, notably including atherosclerosis and diabetes, has been studied for several years. Porphyromonas gingivalis, a prominent component of oral microorganism communities, is the main pathogen that causes periodontitis. As a result of the extensive analysis of this organism, the evidence of its connection to systemic diseases has become more apparent over the last decade. A significant amount of research has explored the role of Porphyromonas gingivalis in atherosclerosis, Alzheimer's disease, rheumatoid arthritis, diabetes, and adverse pregnancy outcomes, while relatively few studies have examined its contribution to respiratory diseases, nonalcoholic fatty liver disease, and depression. Here, we provide an overview of the current state of knowledge about Porphyromonas gingivalis and its systemic impact in an aim to inform readers of the existing epidemiological evidence and the most recent preclinical studies. Additionally, the possible mechanisms by which Porphyromonas gingivalis is involved in the onset or exacerbation of diseases, together with its effects on systemic health, are covered. Although a few results remain controversial, it is now evident that Porphyromonas gingivalis should be regarded as a modifiable factor for several diseases.

A Population-Based Study on the Association between Periodontal Disease and Major Lifestyle-Related Comorbidities in South Korea: An Elderly Cohort Study from 2002-2015

This study determined the association between periodontal disease (PD) and major lifestyle-related comorbidities (LCs) using the database of the nationwide population-based National Health Insurance Service–Elderly Cohort 2002–2015. A nationwide representative sample comprising 558,147 participants, aged 60 years, was analyzed. Univariate and multivariate logistic regression analyses adjusted for sociodemographic and economic factors (sex, age, household income, insurance status, health status, and living area) and major LCs (hypertension, diabetes mellitus, rheumatoid arthritis, osteoporosis, cerebral infarction, angina pectoris, myocardial infarction, erectile dysfunction, lipoprotein disorder, and obesity) were used to determine the association between PD and major LCs. Elderly participants with PD had a higher risk of major LCs (hypertension: odds ratio (OR) = 1.40, diabetes mellitus: OR = 1.22, rheumatoid arthritis: OR = 1.16, osteoporosis: OR = 1.37, erectile dysfunction: OR = 1.73, lipoprotein disorder: OR = 1.50, and obesity: OR = 1.59). Our longitudinal cohort study provided evidence that PD was significantly associated with major LCs in elderly participants. In particular, the association between PD and erectile dysfunction had the highest OR in the multivariate analyses.

Ethanol binge drinking exposure affects alveolar bone quality and aggravates bone loss in experimentally-induced periodontitis

Background

Periodontitis is a multifactorial inflammatory disease of tooth supporting tissues caused by oral biofilms, influenced by environmental and genetic factors, among others. Ethanol consumption has been considered a factor that enhances alveolar bone loss, especially in high doses. The present study aims to investigate the changes promoted by ethanol binge drinking per se or associated with ligature-induced periodontal breakdown on alveolar bone loss.

Materials and methods

Thirty-two Wistar rats were randomly allocated into four groups: control (C), ethanol (3g/kg/day; 3 days On-4 days Off protocol by gavage for 28 days, EtOH), experimental periodontitis (EP) and experimental periodontitis plus ethanol administration (EP+EtOH). On day 14^th, periodontitis was induced by ligatures that were placed around the lower first molars. On day 28^th, the animals were euthanized and mandibles were submitted to stereomicroscopy for exposed root area analysis and micro-computed tomography (micro-CT) for the evaluation of alveolar bone loss and microstructural parameters.

Results

The results revealed that ligature-induced alveolar bone loss is aggravated by ethanol binge drinking compared to controls (1.06 ± 0.10 vs 0.77 ± 0.04; p<0.0001). In addition, binge drinking per se altered the alveolar bone quality and density demonstrating a reduction in trabecular thickness, trabecular number parameter and bone density percentual. Periodontal disorder plus ethanol binge drinking group also demonstrated reduction of the quality of bone measured by trabecular thickness.

Conclusions

In conclusion, intense and episodic ethanol intake decreased alveolar bone quality in all microstructural parameters analyzed which may be considered a modifying factor of periodontitis, intensifying the already installed disease.

[Protein arginine deiminase of oral microbiome plays a causal role in the polyarthritis rheumatoid initiating]

In the last decade, the association between the periodontitis and rheumatoid arthritis (RA) has been established, suggesting that oral microbiome plays a causal role by initiating this chronic autoimmune inflammatory disease of articulation. Both pathogenesis are similar in term of chronic inflammation, tissue breakdown and bone resorption. Molecular aspects have also revealed that citrullination, a post-translational modification catalyzed by peptidyl-arginine deiminases (PADs), is involved in both diseases. For RA, citrullinated proteins production leads to the synthesis the of anti-citrullinated protein antibodies triggering the loss of immune tolerance. In humans, five PADs have been identified. Recently, studies have found that only Porphyromonas species possess PAD. Thus, a major periodontal pathogen, Porphyromonas gingivalis, is able to generate citrullinated epitopes, and could consequently induce anti-citrullinated protein antibodies. In this review, citrullination process, periodontitis and RA are described to put them in relation with molecular, clinical and epidemiological studies establishing the association between periodontitis and RA.

Efficacy of baricitinib on periodontal inflammation in patients with rheumatoid arthritis

OBJECTIVE

Despite a widely recognized bidirectional pathobiologic relationship between rheumatoid arthritis (RA) and periodontal disease, the impact of innovative anti-rheumatic drugs in modulating not only inflammatory and immune articular damage, but also periodontal microenvironment remains debatable. We aimed to evaluate the periodontal status in RA with and without baricitinib, a Janus kinase (JAK) inhibitor, and to better describe association between these entities.

METHODS

We performed a prospective longitudinal 24-weeks study in 21 active RA initiating baricitinib. Standard assessments included a dual rheumatologic (RA activity, disability, serological, inflammatory profile) and dental evaluation comprising plaque index, gingival index, bleeding on probing, probing depth, clinical attachment level.

RESULTS

More than half of RA presented at baseline with chronic periodontitis, as suggested by high prevalence of sites with dental plaque, abnormal bleeding on probing, probing depth and clinical attachment level. Aggressive periodontal disease was reported particularly in disease subsets with excessive inflammatory (serumC reactive protein level) and serologic biomarkers (anti-citrullinated peptide antibodies). Furthermore, significant correlations between dental pathology, disease activity and ACPA levels were also reported (P<0.05). Consistent improvement was noticed in both rheumatoid arthritis characteristics and periodontal status after 24 weeks of baricitinib (P<0.05).

CONCLUSION

RA, particularly severe active ACPA-positive disease, is basically associated with altered periodontal health. JAK blockade through oral baricitinib may be efficient in patients with active RA and potentially able to modulate the inflammatory process in the periodontal tissue.

A cross-sectional investigation into the association between Porphyromonas gingivalis and autoantibodies to citrullinated proteins in a German population

Background

Porphyromonas gingivalis (P.g) is unique among pathogens due to its ability to generate citrullinated proteins in an inflammatory milieu, potentially mediating the loss of immune tolerance, the production of anticitrullinated protein antibodies (ACPAs), and subsequently the development of rheumatoid arthritis (RA). Based on this hypothesis, we set out to investigate whether P.g is linked to ACPAs in a well-characterized German population.

Participants and methods

A total of 600 participants (292 women and 308 men with a mean age of 67 years) of the European Prospective Investigation into Cancer and Nutrition-Potsdam study were selected in 2013, and paired saliva and serum samples were collected. Salivary P.g DNA and serum anticyclic citrullinated peptide (anti-CCP2) levels were quantified by real-time polymerase chain reaction and anti-CCP2 enzyme-linked immunosorbent assay, respectively. In selected participants, additional ACPA fine-specificities were also analysed on a custom-made multiplex peptide array.

Results

Among participants with C-reactive protein greater than 3.0 mg/l, a one-unit increase in P.g DNA was associated with an almost twofold increase in anti-CCP2 levels. Moreover, participants with high P.g DNA had on average approximately 2.8-times higher anti-CCP2 levels when compared with participants with low P.g DNA, (Holm-adjusted p value = 0.01). Furthermore, citrullinated epitopes on α-enolase and vimentin were common ACPA reactivities among participants who also had high P.g DNA and elevated C-reactive protein.

Conclusions

Our study suggests that in specific subgroups of individuals with systemic inflammation, higher salivary P.g DNA is associated with elevated serum ACPA. These data support a role for P.g in the development of anticitrulline immunity.