Causal association between periodontitis and hypertension: evidence from Mendelian randomization and a randomized controlled trial of non-surgical periodontal therapy.

AIMS: Inflammation is an important driver of hypertension. Periodontitis is a chronic inflammatory disease, which could provide a mechanism for pro-hypertensive immune activation, but evidence of a causal relationship in humans is scarce. We aimed to investigate the nature of the association between periodontitis and hypertension. METHODS AND RESULTS: We performed a two-sample Mendelian randomization analysis in the ∼750 000 UK-Biobank/International Consortium of Blood Pressure-Genome-Wide Association Studies participants using single nucleotide polymorphisms (SNPs) in SIGLEC5, DEFA1A3, MTND1P5, and LOC107984137 loci GWAS-linked to periodontitis, to ascertain their effect on blood pressure (BP) estimates. This demonstrated a significant relationship between periodontitis-linked SNPs and BP phenotypes. We then performed a randomized intervention trial on the effects of treatment of periodontitis on BP. One hundred and one hypertensive patients with moderate/severe periodontitis were randomized to intensive periodontal treatment (IPT; sub- and supragingival scaling/chlorhexidine; n = 50) or control periodontal treatment (CPT; supragingival scaling; n = 51) with mean ambulatory 24-h (ABPM) systolic BP (SBP) as primary outcome. Intensive periodontal treatment improved periodontal status at 2 months, compared to CPT. This was accompanied by a substantial reduction in mean SBP in IPT compared to the CPT (mean difference of -11.1 mmHg; 95% CI 6.5-15.8; P < 0.001). Systolic BP reduction was correlated to periodontal status improvement. Diastolic BP and endothelial function (flow-mediated dilatation) were also improved by IPT. These cardiovascular changes were accompanied by reductions in circulating IFN-γ and IL-6 as well as activated (CD38+) and immunosenescent (CD57+CD28null) CD8+T cells, previously implicated in hypertension. CONCLUSION: A causal relationship between periodontitis and BP was observed providing proof of concept for development of clinical trial in a large cohort of hypertensive patients. ClinicalTrials.gov: NCT02131922.

The Effect of Treatment of Denture-related Stomatitis on Peripheral T Cells and Monocytes.

PURPOSE: Systemic immune activation has been recently linked to chronic inflammatory disorders of the oral cavity, particularly to periodontitis. The purpose of this study was to determine whether treatment of a fungus-induced oral inflammation, namely denture-related stomatitis (DRS), can affect the activation of the systemic immune response. MATERIALS AND METHODS: Peripheral blood from patients with denture-related stomatitis caused by Candida albicans infection (n = 15) was collected at three time points: before treatment with nystatin, at the end of therapy and 2 months after finishing therapy. Activation of T cells and monocytes was assessed by flow cytometry. RESULTS: The percentages of peripheral lymphocytes, T cells and their subpopulations, as well as monocytes were similar before, immediately following and two months after nystatin treatment. Cells expressing early activation marker CD69 and RANTES C-C chemokine receptor type 5 significantly increased immediately after treatment and returned to baseline levels after two months. Th17 cells, which have been implicated in the pathogenesis of DRS, remained unchanged. Central memory CD4+ subset and intermediate subset of monocytes were lower after therapy and this effect was sustained for two months. CONCLUSION: Treatment of denture-related stomatitis does not seem to affect the general state of the cellular components of the immune system. The results suggest a potential proinflammatory effect of the antifungal agent, nystatin. Although transient and not intense, this effect might be of particular clinical importance, because of relationships between inflammation and certain diseases. Further studies are required to clarify this aspect.

Treatment of denture-related stomatitis improves endothelial function assessed by flow-mediated vascular dilation.

INTRODUCTION: The presence of oral inflammation has recently been linked with the pathogenesis of cardiovascular diseases. While numerous studies have described links between periodontitis and endothelial dysfunction, little is known about the influence of denture-related stomatitis (DRS) on cardiovascular risk. Therefore, the aim of this study was to determine whether the treatment of DRS can lead to improvement of the clinical measures of vascular dysfunction. MATERIAL AND METHODS: The DRS patients were treated with a local oral antifungal agent for 3 weeks. Blood pressure, flow-mediated dilatation (FMD) and nitroglycerine-mediated vascular dilatation (NMD) were measured during three study visits: before treatment, one day and two months after conclusion of antifungal therapy. RESULTS: Flow-mediated dilatation measurements showed significant improvement of endothelial function 2 months after treatment (FMD median 5%, 95 CI: 3-8.3 vs. 11%, 95% CI: 8.8-14.4; p < 0.01), while there was no difference in control, endothelium-independent vasorelaxations (NMD; median = 15.3%, 95% CI: 10.8-19.3 vs. 12.7%, 95% CI: 10.6-15; p = 0.3). Other cardiovascular parameters such as systolic (median = 125 mm Hg; 95% CI: 116-129 vs. 120 mm Hg, 95% CI: 116-126; p = 0.1) as well as diastolic blood pressure and heart rate (median = 65.5 bpm, 95% CI: 56.7-77.7 vs. 71 bpm, 95% CI: 66.7-75; p = 0.5) did not change during or after the treatment. CONCLUSIONS: Treatment of DRS is associated with improvement of endothelial function. Since endothelial dysfunction is known to precede the development of severe cardiovascular disorders such as atherosclerosis and hypertension, patients should be more carefully screened for DRS in general dental practice, and immediate DRS treatment should be advised.

Systemic T Cells and Monocyte Characteristics in Patients with Denture Stomatitis.

PURPOSE: Chronic inflammatory disorders of the oral cavity, such as periodontitis, were recently linked to systemic immune activation. Since fungal oral infections have not yet been studied in this respect, the aim of our study is to determine whether the local inflammation caused by oral fungal infection of the palatal tissue (denture stomatitis-DS) is associated with the systemic inflammatory response. This question is becoming essential as the population ages. MATERIALS AND METHODS: Peripheral blood of DS patients (n = 20) and control patients (n = 24) was assessed with flow cytometry to determine lymphocyte and monocyte profiles. Intracellular cytometric analysis was carried out to establish cytokine production by T cells. DS was diagnosed based on clinical symptoms of DS such as swelling and redness of oral mucosa, confirmed by microbiological swabs for fungal colonization with Candida species. The control group was recruited from denture users without clinical and microbiological signs of oral infections. RESULTS: Percentages of peripheral lymphocytes, T cells, monocytes, and their subpopulations were similar in both studied groups. The exception was median percentages of CD25+ T cell subsets, which were significantly lower in DS patients than in control subjects. This reduction was observed in both CD4 T cell subset (16.7% and 28.1%; p = 0.0006) and CD8 T cell subset (4.6% and 7.0%; p = 0.007) CONCLUSIONS: While DS and associated local fungal infection do not overtly affect activation of monocytes or lymphocytes, the number of CD 25+ T cells is significantly lower in the DS patients, possibly indicating limited potential for the infection clearance in denture-using aging patients.

Denture-related stomatitis is associated with endothelial dysfunction.

UNLABELLED: Oral inflammation, such as periodontitis, can lead to endothelial dysfunction, accelerated atherosclerosis, and vascular dysfunction. The relationship between vascular dysfunction and other common forms of oral infections such as denture-related stomatitis (DRS) is unknown. Similar risk factors predispose to both conditions including smoking, diabetes, age, and obesity. Accordingly, we aimed to investigate endothelial function and major vascular disease risk factors in 44 consecutive patients with dentures with clinical and microbiological features of DRS (n = 20) and without DRS (n = 24). While there was a tendency for higher occurrence of diabetes and smoking, groups did not differ significantly in respect to major vascular disease risk factors. Groups did not differ in main ambulatory blood pressure, total cholesterol, or even CRP. Importantly, flow mediated dilatation (FMD) was significantly lower in DRS than in non-DRS subjects, while nitroglycerin induced vasorelaxation (NMD) or intima-media thickness (IMT) was similar. Interestingly, while triglyceride levels were normal in both groups, they were higher in DRS subjects, although they did not correlate with either FMD or NMD. CONCLUSIONS: Denture related stomatitis is associated with endothelial dysfunction in elderly patients with dentures. This is in part related to the fact that diabetes and smoking increase risk of both DRS and cardiovascular disease.

Endothelial function assessment in atherosclerosis: comparison of brachial artery flow­mediated vasodilation and peripheral arterial tonometry.

INTRODUCTION:  Endothelial dysfunction, characterized by the loss of nitric oxide bioavailability, is a key element in the pathogenesis of atherosclerosis and an important prognostic factor in cardiovascular diseases. Therefore, the development of reliable, safe, and noninvasive methods of endothelial function assessment is important for their use in cardiovascular risk stratification. Brachial artery flow­mediated dilation (FMD) is widely used in research but technical difficulties and problems with calibration between laboratories limit its clinical use. Reactive hyperemia-peripheral artery tonometry (RH­PAT, EndoPAT) has been developed as a simpler, cheaper, and potentially more reproducible method. OBJECTIVES:  We aimed to investigate associations between RH­PAT and FMD in relation to atherosclerotic risk factor profile. PATIENTS AND METHODS:  The study involved 80 subjects (52 men, 28 women) aged 43.6 ±14.8 years, with moderate­to­low cardiovascular risk (mean SCORE, 2.2% ±2%), in whom FMD, RH­PAT, and intima-media thickness (IMT) were determined. RESULTS:  The reactive hyperemia index (RHI) measured by RH­PAT correlated with FMD (r = 0.35, P <0.01). However, no significant correlation was observed between RHI and IMT, SCORE, or the number of classical atherosclerotic risk factors (hypertension, smoking, diabetes, hypercholesterolemia), while FMD was significantly correlated with IMT (r = -0.53, P <0.001), risk factors (r = -0.55, P <0.05), and SCORE (r = -0.4, P <0.05). CONCLUSIONS:  Despite its technical requirements, FMD is a more sensitive method than RH­PAT in evaluating the effect of classical atherosclerotic risk factors on vascular endothelial function. Microvasculature response during RH­PAT needs to be further studied, including the assessment of nonendothelial factors that may affect the measurements, before RH­PAT becomes the universal tool for the evaluation of the endothelial cells.