Oral health-related quality of life in patients with early rheumatoid arthritis is associated with periodontal inflammation and painful temporomandibular disorders: a cross-sectional study

Exploring the causal relationships between rheumatoid arthritis and oral phenotypes: a genetic correlation and Mendelian randomization study

Background

Rheumatoid arthritis (RA) frequently presents with oral manifestations, including gingival inflammation, loose teeth, and mouth ulcers; however, the causal connections between these conditions remain unclear. This study aims to explore the genetic correlations and causal relationships between RA and prevalent oral phenotypes.

Methods

Using summary data from genome-wide association studies of European populations, a cross-trait linkage disequilibrium score regression was conducted to estimate the genetic correlations between RA and six oral phenotypes. Subsequently, a two-sample Mendelian randomization (MR) approach was employed to assess the causal relationships, corroborated by various sensitivity analyses. Heterogeneity was addressed through the RadialMR method, while potential covariates were corrected using the multivariable MR approach.

Results

A significant negative genetic correlation was detected between RA and denture usage (rg = -0.192, p = 4.88 × 10-8). Meanwhile, a heterogenous causal relationship between RA and mouth ulcers was observed (OR = 1.027 [1.005-1.05], p = 0.016, P heterogeneity = 4.69 × 10-8), which remained robust across sensitivity analyses. After excluding outlier variants, the results demonstrated robustly consistent (OR = 1.021 [1.008-1.035], p = 1.99 × 10-3, P heterogeneity = 0.044). However, upon adjusting for covariates such as smoking, alcohol consumption, body mass index, and obesity, the significance diminished, revealing no evidence to support independent genetic associations.

Conclusion

Genetically predicted RA increases the risk of mouth ulcers, and a negative genetic correlation is identified between RA and denture use. The observed heterogeneity suggests that shared immunological mechanisms and environmental factors may play significant roles. These findings highlight the importance of targeted dental management strategies for RA patients. Further clinical guidelines are required to improve oral health among vulnerable RA patients.

Associations of inflammatory polyarthritis with clinical and radiological findings of temporomandibular disorders

OBJECTIVE

To evaluate the association of different forms of inflammatory polyarthritis with clinical signs of temporomandibular disorders (TMD) and radiological findings in temporomandibular joint (TMJ), based on a nationwide health survey in Finland. The aim was also to assess the presence of clinical and radiological TMD findings in subjects with increased risk for developing rheumatoid arthritis (RA).

MATERIAL AND METHODS

Anationally representative sample included 6331 Finnish adults who participated in the Health 2000 Survey (BRIF8901). Subjects were examined for signs of TMD, findings in panoramic radiograph of TMJ, musculoskeletal health and serology (rheumatoid factor, RF, and anti-cyclic citrullinated peptide, aCCP).

RESULTS

Sixty-four percent of seronegative RAand 60% of seropositive RAsubjects had at least one sign of TMD. While adjusting for confounding factors (gender, age, dentures and smoking history), RAwas significantly associated with crepitation and abnormal radiological findings in TMJ. Seronegative RAwas also associated with restricted mouth opening. Systemic autoimmunity associated with RA("at risk of RA") was not associated with clinical or radiological TMD findings.

CONCLUSIONS

Clinical and radiological findings of TMD are more prevalent among subjects with inflammatory polyarthritis than among the population in general in the Finnish adult population.

Temporomandibular disorders in immune-mediated rheumatic diseases of the adult: A systematic review

OBJECTIVE

To systematically review the literature concerning temporomandibular disorders (TMDs) in immune-mediated rheumatic diseases (IMRDs) of the adult. The temporomandibular joint (TMJ) outcomes used in clinical studies, the prevalence of TMDs in IMRDs and the risk factors for their development were qualitatively synthetized.

METHODS

A literature search on PubMed Central, Embase and Cochrane Library databases was performed for studies including TMJ outcomes in IMRDs patients compared with healthy controls, other rheumatic diseases or in the assessed IMRDs patients after follow-up and treatment. Among the IMRDs of the adult, original articles investigating TMJ involvement in inflammatory polyarthritides and/or autoimmune connective tissue diseases were considered. The quality of the studies was scored using the Newcastle-Ottawa scale (NOS).

RESULTS

Of the 3259 screened abstracts, 56 papers were included in the systematic review. Most of the papers (77%) investigated TMDs in rheumatoid arthritis (RA) with a prevalence of signs and symptoms varying from 8% to 70%. The risk factors for TMDs development in RA were female sex, younger age, anti-citrulline peptide autoantibodies (ACPA) positivity, higher disease activity, cervical spine involvement, cardiovascular and neuropsychiatric comorbidities. Ten papers (18%) evaluated TMDs in spondylarthritides (SpA) reporting a prevalence of symptoms and signs in 12%-80% of patients with higher TMDs prevalence in patients with radiographic spine involvement, skin psoriasis and HLADRB1×01 positivity. Among autoimmune connective tissue diseases (CTDs), systemic sclerosis (SSc) displayed the highest evidence of TMDs patient-reported outcomes (PROs) and clinical findings (20-93%), followed by systemic lupus erythematosus (SLE) in 18-85%, primary Sjogren's syndrome (24-54%) and idiopathic inflammatory myopathies (4-26%). In SSc and SLE, TMDs were more frequent in patients with higher disease activity and duration, correlating with the extent of skin fibrosis in SSc and with renal involvement in SLE.

CONCLUSION

TMDs in IMRDs display a significant relevance in the rheumatological clinical practice even if often misdiagnosed. This burden is epidemiologically important in terms of PROs and clinical findings which correlate with disease activity in RA, SpA, SSc and SLE. The early recognition and multidisciplinary management of TMDs is warranted and should be aimed at hindering the TMJ structural damage maximizing the quality of life of patients.

Dental Caries in Adult Patients with Rheumatoid Arthritis-A Systematic Review

Patients suffering from rheumatoid arthritis (RA) are repeatedly affected by oral diseases or complaints, including xerostomia, periodontitis and dental caries. The aim of this systematic review was the evaluation of caries prevalence and/or incidence in patients with RA. Within this review, there is a systematic search of the literature based on PubMed, Web of Science and Scopus. Two independent researchers performed the search in February 2023. The search terms were "dental caries" AND "rheumatoid arthritis". Additionally, a manual search completed the review process. Studies on adult patients (age ≥ 18 years) only suffering from RA were included. Studies had to explicitly report on the prevalence or incidence of dental caries. The respective studies were checked regarding suitability and, if they were eligible, analyzed qualitatively. A quality appraisal was performed for all of the analyzed studies. A total of 336 studies were detected, of which 16 studies met the in- and exclusion criteria. The sample sizes of the clinical investigations ranged between 13 and 1337 participants. Twelve studies evaluated a healthy control group. In 8/12 studies, a significant difference in the prevalence/incidence of caries was found between RA patients and controls. The majority of the studies applied the decayed (DT), missing and filled teeth index (DMFT) for the diagnosis of caries. On average (mean value), 0.8 to 5.79 carious teeth per patient were reported across the studies. There was no information on the stadium, activity or location of caries (e.g., root caries) in any study. Quality appraisal revealed a moderate quality for most studies. In conclusion, caries prevalence was heterogeneous across studies, while a higher caries prevalence was repeatedly reported in RA patients against controls. Further research regarding dental caries in RA appears recommendable; multidisciplinary, patient-centered dental care for patients with RA should be fostered to improve patients' dental health status.

Periodontal Inflamed Surface Area (PISA) associates with composites of salivary cytokines

BACKGROUND

Periodontal disease (PerioD) is a chronic, complex inflammatory condition resulting from the interaction between subgingival dysbiotic bacteria and the host immune response leading to local inflammation. Since periodontal inflammation is characterized by multiple cytokines effects we investigated whether Periodontal Inflamed Surface Area (PISA), a continuous measure of clinical periodontal inflammation is a predictor of composite indexes of salivary cytokines.

METHODS AND FINDINGS

In a cross-sectional study of 67 healthy, well-educated individuals, we evaluated PISA and several cytokines expressed in whole stimulated saliva. Two salivary cytokine indexes were constructed using weighted and unweighted approaches based on a Principal Component Analysis [named Cytokine Component Index (CCI)] or averaging the (standardized) level of all cytokines [named Composite Inflammatory Index (CII)]. In regression analysis we found that PISA scores were significantly associated with both salivary cytokine constructs, (CCI: part R = 0.51, p<0.001; CII: part R = 0.40, p = 0.001) independent of age, gender and BMI showing that single scores summarizing salivary cytokines correlated with severity of clinical periodontal inflammation.

CONCLUSIONS

Clinical periodontal inflammation may be reflected by a single score encompassing several salivary cytokines. These results are consistent with the complexity of interactions characterizing periodontal disease. In addition, Type I error is likely to be avoided.

Oral Health and Frailty in Community-Dwelling Older Adults in the Northern Netherlands: A Cross-Sectional Study

The aim of this study was to explore the association between oral health and frailty in community-dwelling Dutch adults aged 55 years and older. Included were 170 participants (n = 95 female [56%]; median age 64 years [IQR: 59−69 years]). Frailty was assessed by the Groningen Frailty Indicator. Oral health was assessed by the Oral Health Impact Profile-14-NL (OHIP-NL14). OHIP-NL14 item scores were analyzed for differences between frail and non-frail participants. Univariate and multivariate logistic regression analyses were performed to assess the association between oral health and presence of frailty. The multivariate analysis included age, gender, and depressive symptoms as co-variables. After adjustment, 1 point increase on the OHIP-NL14 scale was associated with 21% higher odds of being frail (p = 0.000). In addition, significantly more frail participants reported presence of problems on each OHIP-NL14 item, compared to non-frail participants (p < 0.003). Contrast in prevalence of different oral health problems between frail and non-frail was most prominent in ‘younger’ older adults aged 55−64 years. In conclusion: decreased oral health was associated with frailty in older adults aged ≥55 years. Since oral health problems are not included in most frailty assessments, tackling oral health problems may not be sufficiently emphasized in frailty policies.