Association of adipokine levels with obesity in periodontal health and disease: A systematic review with meta-analysis and meta-regression

This study aimed to investigate the levels of serum, gingival crevicular fluid (GCF), and salivary adipokines and their possible relationship with periodontitis and obesity. An electronic search was conducted in the following databases: PubMed/ Medline, Scopus, and EBSCOhost through February 2023. Two independent reviewers screened the titles, abstracts, and full text of all the studies. Studies comparing the levels of adipokines in GCF, serum, and/or saliva in subjects with obesity and periodontitis (group 1), subjects with normal weight and periodontitis (group 2), and subjects with obesity and gingival health (group 3) were included. Meta-analyses and meta-regression were performed on the data from included studies. Seventeen studies with study participants ranging from 30 to 120 were included with subjects in each group ranging from 10 to 40. There was a significant increase in levels of serum TNF-α, leptin, IL-6, and CRP between groups 1 and 2 (p < .05). In GCF, TNF-α and resistin levels were significantly higher (p < .05) in Group 1 vs. 2. Serum level of leptin was higher for group 1 vs. 3 (p < .05). Meta-regression analysis revealed that the obesity definition (body mass index (BMI) cut-off value >25 or >30) was significant for serum resistin (p < .05) and GCF resistin (p < .05) between group 1 and 2. The current analysis indicates that both periodontitis and obesity can modulate the pro-inflammatory cytokines at systemic and local levels. This bidirectional interaction of periodontitis and obesity via the inflammation pathway seems likely plausible. Further studies are required to elucidate this mechanism in more detail.

Exploring the bi-directional relationship between periodontitis and dyslipidemia: a comprehensive systematic review and meta-analysis

AIM

As periodontitis and dyslipidemia are diseases that occur with high incidence, the relationship between them has attracted much attention. Previous studies on these diseases have tended to focus on lipid parameters and periodontitis, we aimed to investigate the relationship between dyslipidemia and periodontitis.

MATERIALS AND METHODS

A comprehensive search to identify the studies investigating the relationship between dyslipidemia and periodontitis was performed on PubMed, Web of Science and Cochrane Library before the date of August, 2023. Studies were considered eligible if they contained data on abnormal blood lipid parameters and periodontitis. Studies that reported mean differences and 95% confidence intervals or odds ratios were used.

RESULTS

A total of 73 publications were included in the meta-analysis. Hyper total cholesterol (TC), triglycerides (TGs), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL) and lower high-density lipoprotein (HDL) levels are risk factors for periodontitis. Periodontal disease is a risk factor for high TG and low HDL levels. Three months after periodontal treatment, the levels of TC, TG and HDL were significantly improved, and statin treatment only improved gingival index (GI) levels compared to that of the dietary control.

CONCLUSIONS

The findings reported here suggest that the mutual promotion of periodontitis and dyslipidemia can be confirmed. Non-surgical periodontal therapy may improve lipid abnormalities. It can't be demonstrated whether systematic application of statins have a better effect on the improvement in periodontal status in patients with dyslipidemia compared to that of the control.

Systemic benefits of periodontal therapy in patients with obesity and periodontitis: a systematic review

This systematic review aimed to answer the focused question: "What are the benefits of subgingival periodontal therapy on blood hematological and biochemical index, biomarkers of inflammation and oxidative stress, quality of life, and periodontal pathogen counts in patients with obesity and periodontitis?". A systematic literature search was performed in six databases: PubMed, Embase, LILACS, Web of Science, Cochrane and SCOPUS and other sources, and a manual search was conducted as well. Inclusion criteria were randomized and non-randomized clinical trials, and before-and-after studies on patients with obesity subjected to periodontal therapy. The results were synthesized qualitatively. Risk of bias within studies was assessed using RoB 2 and ROBINS-I tools. The certainty of evidence was evaluated following the GRADE approach. Three randomized controlled trials and 15 before-and-after studies were included. Randomized controlled trials were considered to have a low risk of bias, as compared to before-and-after studies assessed as having low, serious, and critical risks of bias. Non-surgical periodontal therapy plus azithromycin, chlorhexidine, and cetylpyridinium chloride reduced blood pressure and decreased serum levels of HbA1c, hsCRP, IL-1β, and TNF-α. Salivary resistin level also decreased in patients with obesity and periodontitis after therapy and chlorhexidine mouth rinse. Before-and-after data suggest an improvement in total cholesterol, LDL, triglycerides, insulin resistance, C3, GCF levels of TNF-α, chemerin, vaspin, omentin-1, visfatin, 8-OHdG, and periodontal pathogen counts after therapy.

Effect of non-surgical periodontal treatment on cytokines/adipocytokines levels among periodontitis patients with or without obesity: a systematic review and meta-analysis

BACKGROUND

The objective of this systematic review and meta-analysis was to evaluate the effects of non-surgical periodontal therapy (NSPT) on inflammatory-related cytokines/adipocytokines in periodontitis patients with or without obesity.

METHODS

We followed the preferred reporting items for systematic reviews and meta-analyses statement and registered the study (CRD42022375331) in the Prospective International Register of Systematic Reviews. We screened randomized-controlled trials and controlled clinical trials from six databases up to December 2022. Quality assessment was performed with RoB-2 and ROBINS-I tools for randomized trials and non-randomized trials, respectively. Meta-analysis was carried out using a random-effect model.

RESULTS

We included seventeen references in the systematic analysis, and sixteen in the meta-analysis. Baseline results of pro-inflammatory biomarkers, including serum interleukin (IL)-6, serum and gingival crevicular fluid (GCF), tumor necrosis factor (TNF)-a, serum C-reactive protein (CRP)/hs-CRP, and serum and GCF resistin, were higher in obesity subjects than in normal weight subjects. The effect of NSPT with respect to levels of cytokines/adipocytokines, including IL-6, TNF-a, CRP/hs-CRP, resistin, adiponectin, leptin and retinol binding protein 4 (RBP4), were then analyzed in the systematic and meta-analysis. After three months of NSPT, serum (MD = -0.54, CI = -0.62 - -0.46), and GCF (MD = -2.70, CI = -4.77 - -0.63) levels of IL-6, along with the serum RBP4 (MD = -0.39, CI = -0.68-0.10) decreased in periodontitis individuals with obesity. NSPT also improved GCF adiponectin levels after three months (MD = 2.37, CI = 0.29 - 4.45) in periodontitis individuals without obesity.

CONCLUSIONS

Obese status altered the baseline levels of cytokines/adipocytokines (serum IL-6, serum and GCF TNF-a, serum CRP/hs-CRP, and serum and GCF resistin). Then NSPT can shift the levels of specific pro-inflammatory mediators and anti-inflammatory mediators in biological fluids, both in obesity and non-obesity individuals. NSPT can reduce serum and GCF IL-6 levels together with serum RBP4 level in individuals with obesity after 3 months, besides, there is no sufficient evidence to prove that obese patients have a statistically significant decrease in the levels of other cytokines compared to patients with normal weight. NSPT can also increase GCF adiponectin level in normal weight individuals after 3 months. Our findings imply the potential ideal follow-up intervals and sensitive biomarkers for clinical bioanalysis in personalized decision-making of effect of NSPT due to patients' BMI value.

Periodontal and systemic health of morbidly obese patients eligible for bariatric surgery: a cross-sectional study

Background

In obese patients, periodontitis might be associated with deprived systemic health. Edmonton obesity staging system (EOSS) is a new tool for classification of obesity that considers the metabolic, physical, and psychological health. The cross-sectional study aimed to evaluate the periodontal status of morbidly obese patients eligible for bariatric surgery and the association between periodontitis, obesity-related comorbidities, and EOSS.

Methods

Morbidly obese patients eligible for bariatric surgery underwent detailed periodontal examination and were divided into the periodontitis group (PG) and the non-periodontitis group (NPG). The medical and demographic data were obtained from medical files, while behavioural data were obtained by the interview. Descriptive statistics and simple statistical tests were used to summarise the characteristics of the sample and the differences between PG and NPG. The logistic regression models were used to calculate the association (odds ratio (OR)) between periodontitis and obesity-related diseases and EOSS.

Results

The study included 79 patients, with an average BMI of 44.6 kg/m² (SD = 7.2). The prevalence of periodontitis was 65% (CI 95% 53%-75%). PG patients (n = 51) were older, more often smokers and were more often hypertensive than NPG patients (n = 28) (p < 0.05). Hypertension was positively associated with periodontitis with adjusted OR 3.98 (95% CI 1.23–12.8; p = 0.021)) and age with adjusted OR 1.06, (95% CI 1.01–1.13; p = 0.038)), while other tested conditions (diabetes, dyslipidaemia, and smoking habits) did not show significant association with periodontitis. Periodontitis did not correlate with EOSS or other obesity-related comorbidities (p > 0.05).

Conclusion

The morbidly obese patients eligible for bariatric surgery show a high prevalence of periodontitis and, therefore, are advised to be examined by a dentist before undergoing surgery. They have higher odds of hypertension but not of other obesity-related diseases or higher stages of EOSS. The medical personnel should raise awareness among obese patients on the potential association of poor periodontal health with hypertension.

Trial registration

NCT04653714.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-022-02207-0.

Effects of periodontitis and periodontal treatment on systemic inflammatory markers and metabolic profile in obese and non-obese rats

BACKGROUND

Little is known about a synergistic effect of periodontitis and obesity on systemic biomarkers and a possible effect periodontal treatment may exert. This study aimed to evaluate the impact of periodontitis and periodontal treatment on systemic inflammation and metabolic profile in obese and non-obese rats.

METHODS

60 male Wistar rats were randomly divided in six groups differentiated by diet and periodontal status: no periodontitis (G1 and G4), untreated ligature-induced periodontitis (G2 and G5) and treated ligature-induced periodontitis (G3 and G6). Groups G4, G5 and G6 were exposed to cafeteria diet to induce obesity. Periodontitis was induced by silk ligatures over 4 weeks (G2, G3, G5, G6). Rats in G3 and G6 received scaling and root planning and were followed for additional 4 weeks. After sacrifice, serum levels of C-reactive protein (CRP), interleukin (IL)-1β, IL-6, IL-10, IL-17a, tumor necrosis factor alfa (TNF-α), glucose, triglycerides, and total cholesterol (TC) were compared between groups.

RESULTS

CRP was significantly higher in obese rats with than without periodontitis (G5 = 10.15μg/L vs. G4 = 4.47μg/L, p = 0.01). No beneficial effects of periodontal treatment were observed for CRP levels, IL-6, IL-1β, IL-17a, TNF-α, glucose and triglycerides. Treated periodontitis (G6) exhibited significantly lower TC than the periodontitis group (G5) in obese rats.

CONCLUSION

Periodontitis increased serum CRP in obese rats, indicating a synergistic role of periodontitis in the systemic inflammatory burden triggered by obesity. The treatment of induced periodontitis reduced TC levels in obese rats. This article is protected by copyright. All rights reserved.

Distinct Lipidomic Signatures in People Living With HIV: Combined Analysis of ACTG 5260s and MACS/WIHS

CONTEXT

Disentangling contributions of HIV from antiretroviral therapy (ART) and understanding the effects of different ART on metabolic complications in persons living with HIV (PLHIV) has been challenging.

OBJECTIVE

We assessed the effect of untreated HIV infection as well as different antiretroviral therapy (ART) on the metabolome/lipidome.

METHODS

Widely targeted plasma metabolomic and lipidomic profiling was performed on HIV-seronegative individuals and people living with HIV (PLHIV) before and after initiating ART (tenofovir/emtricitabine plus atazanavir/ritonavir [ATV/r] or darunavir/ritonavir [DRV/r] or raltegravir [RAL]). Orthogonal partial least squares discriminant analysis was used to assess metabolites/lipid subspecies that discriminated between groups. Graphical lasso estimated group-specific metabolite/lipid subspecies networks associated with the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR). Correlations between inflammatory markers and metabolites/lipid subspecies were visualized using heat maps.

RESULTS

Of 435 participants, 218 were PLHIV. Compared to HIV-seronegative individuals, ART-naive PLHIV exhibited higher levels of saturated triacylglycerols/triglycerides (TAGs) and 3-hydroxy-kynurenine, lower levels of unsaturated TAGs and N-acetyl-tryptophan, and a sparser and less heterogeneous network of metabolites/lipid subspecies associated with HOMA-IR. PLHIV on RAL vs ATV/r or DRV/r had lower saturated and unsaturated TAGs. Positive correlations were found between medium-long chain acylcarnitines (C14-C6 ACs), palmitate, and HOMA-IR for RAL but not ATV/r or DRV/r. Stronger correlations were seen for TAGs with interleukin 6 and high-sensitivity C-reactive protein after RAL vs ATV/r or DRV/r initiation; these correlations were absent in ART-naive PLHIV.

CONCLUSION

Alterations in the metabolome/lipidome suggest increased lipogenesis for ART-naive PLHIV vs HIV-seronegative individuals, increased TAG turnover for RAL vs ATV/r or DRV/r, and increased inflammation associated with this altered metabolome/lipidome after initiating ART. Future studies are needed to understand cardiometabolic consequences of lipogenesis and inflammation in PLHIV.

What Are the Clinical and Systemic Results of Periodontitis Treatment in Obese Individuals?

Purpose of Review

Periodontitis and obesity are characterized by a dysregulated inflammatory state. Obese individuals have a higher chance of presenting periodontitis. Clinical studies in different populations demonstrate that individuals with obesity have worse periodontal conditions. This current review aims to explore recent literature to understand what the impacts of obesity on periodontal treatment outcomes are and to learn whether periodontal treatment can improve systemic biomarkers in obese individuals.

Recent Findings

Short- and long-term evaluations demonstrated that non-surgical periodontal treatment could improve clinical parameters in obese individuals, represented as the reduction in mean probing depth, sites with probing depth ≥ 4 mm, and extension of bleeding on probing. However, obese individuals may have less clinical improvement when compared to normal-weight individuals with a similar periodontal profile. Additionally, periodontal treatment may contribute to a reduction in systemic levels of retinol-binding protein 4 and leptin, while promoting an increase in systemic levels of adiponectin.

Summary

Overall, obese individuals with periodontitis can significantly benefit from non-surgical periodontal treatment. However, clinical improvements seem to be less prominent in obese individuals with periodontitis compared to non-obese individuals with similar periodontal status. Nevertheless, periodontal treatment may impact significantly on the reduction of several biochemical biomarkers of obesity with or without weight reduction. Further investigations are needed to improve our comprehension of the mechanisms underlying those findings.

Association between periodontal inflammation and serum lipid profile in a healthy population: A cross-sectional study

AIMS

The impact of periodontal inflammation on lipid metabolism is controversial. This study aimed to investigate the association between full-mouth periodontal inflammation and serum lipid levels.

MATERIALS AND METHODS

In this cross-sectional study, we performed periodontal and bacteriological examinations during medical checkup on 131 subjects. The association between the periodontal inflamed surface area (PISA) and the lipid markers was analyzed by multiple linear regression, adjusting for age, sex, smoking, and body mass index.

RESULTS

Overall, 118 medically healthy participants were analyzed. The proportions of none, mild, moderate, and severe periodontitis were 37.3%, 32.2%, 25.4%, and 5.1%, respectively. Multivariate analysis showed that high-density lipoprotein cholesterol was significantly higher in participants with the lowest tertile of PISA values (PISA low, coefficient: 7.94; 95% confidence interval [CI]: 1.63, 14.26, p = .01) compared to those in other tertiles (PISA high). Low-density/high-density lipoprotein cholesterol and total/high-density lipoprotein cholesterol ratios were significantly lower in the PISA-low group than the PISA-high group (coefficient: -0.26 and -0.30; 95% CI: -0.50, -0.02, and -0.59, -0.0002; p = .04 and .0498). Serum high-sensitivity C-reactive protein level, but not serum Porphyromonas gingivalis antibody titer, partly explained the association between PISA and high-density lipoprotein cholesterol. A significant interaction between female sex and PISA values toward high-density lipoprotein cholesterol level was detected.

CONCLUSION

Periodontal inflammation was inversely associated with higher high-density lipoprotein cholesterol, especially in females. Elevated serum C-reactive protein partly explained this association.

Association between clinical measures of gingival inflammation and obesity in adults: systematic review and meta-analyses

OBJECTIVE

This study aimed to systematically review the literature about the association between clinical measures of gingival inflammation and obesity in adults.

MATERIAL AND METHODS

Searches for studies were performed in five databases (Medline-PubMed, Scopus, Web of Science, Cochrane Library, and Embase) to compile studies of any design that evaluated the association between clinical measures of gingival inflammation and obesity in adults. Selection of studies, data extraction and risk of bias analysis were performed independently by two reviewers, and a third researcher was involved to resolve disagreements. Meta-analyses were performed for measures of gingival inflammation as compared to body mass index (BMI). Independent analyses were performed for studies involving periodontitis, gingivitis, and population-based/studies that did not provide a periodontal diagnosis. Standard mean deviation (SMD) and its 95% confidence interval (95%CI) were estimated.

RESULTS

Ninety studies were included (cross-sectional/clinical trials [n=82], case-control [n=3], cohorts [n=5]). Most of the studies demonstrated no significant difference in the measures of gingival inflammation regardless of the comparison performed. However, meta-analysis showed that among individuals with periodontitis, significantly higher levels of gingival inflammation are observed in those with obesity (n of individuals=240) when compared to those who were not obese (n of individuals=574) (SMD:0.26; 95%CI:0.07-0.44). When considering population-based/those studies that did not provide periodontal diagnosis, significantly higher measures of gingival inflammation were observed in the groups with higher BMI.

CONCLUSIONS

Within the limitations of the present study, it was concluded that higher measures of gingival inflammation may be expected for those with higher BMI.

CLINICAL RELEVANCE

Clinicians must be aware that higher measures of gingival inflammation may be expected for individuals with higher BMI. However, there is a necessity for further longitudinal studies regarding the association between obesity and gingival inflammation.

Effect of compliance during periodontal maintenance therapy on c-reactive protein levels: a 6-year follow-up

AIMS

To longitudinally evaluate the effects of compliance during periodontal maintenance therapy (PMT) on C-reactive protein (CRP) levels and its relation to periodontal status.

MATERIALS AND METHODS

A subsample comprising of 30 matched pairs was taken from a previous 6-year longitudinal study under PMT. Pairs were composed of one regular (RC) and one irregular (IC) compliers, matched by age and sex. Periodontal parameters and plasma samples were collected at 3 times: T1[prior to active periodontal therapy (APT)], T2(after APT), and T3(after 6 years). CRP plasma levels were quantified using ELISA.

RESULTS

RC presented better clinical periodontal status, lower recurrence of periodontitis (sites with PD ≥4 mm and CAL ≥3 mm, together with the persistence and/or presence of BOP and/or suppuration, during any of the subsequent recall evaluations) and significant reductions in CRP levels over time [(T1: RC = 3.64 ± 2.13 and IC = 3.92 ± 2.02 mg/L) and (T3: RC = 2.12 ± 1.39 mg/L and IC = 3.71 ± 1.82 mg/L)]. Logistic regression analysis demonstrated that individuals with periodontitis recurrence presented 2.19 higher chances of presenting altered CRP levels (values ≥3 mg/L- T2 to T3) than those without periodontitis recurrence (95%CI:1.16-3.27; p = 0.017).

CONCLUSIONS

Higher CRP plasma levels were associated with higher recurrence of periodontitis and worse clinical periodontal parameters among IC when compared to RC.

Periodontal therapy and cardiovascular risk

Cardiovascular diseases are the worldwide leading cause of mortality. Cardiovascular diseases are noncommunicable conditions with a complex pathogenesis, and their clinical manifestations include major cardiovascular events such as myocardial infarction and stroke. Epidemiologic evidence suggests a consistent association between periodontitis and increased risk of cardiovascular diseases. Some evidence supports a beneficial effect of the treatment of periodontitis on both surrogate and hard cardiovascular outcomes. This narrative review has been conducted as an update of the most recent evidence on the effects of periodontitis treatment on cardiovascular outcomes since the last commissioned review of the European Federation of Periodontology-American Academy of Periodontology World Workshop in 2012. Newer evidence originating from published randomized controlled trials confirms a positive effect of periodontal treatment on surrogate measures of cardiovascular diseases, whereas there have been no randomized controlled trials investigating the effect of periodontal treatment on the incidence of cardiovascular disease events such as myocardial infarction and stroke. In conclusion, there is sufficient evidence from observational and experimental studies on surrogate cardiovascular measures to justify the design and conduct of appropriately powered randomized controlled trials investigating the effect of effective periodontal interventions on cardiovascular disease outcomes (ie, myocardial infarction and stroke) with adequate control of traditional cardiovascular risk factors.

Evaluation of recurrence of periodontal disease after treatment in obese and normal weight patients: Two-year follow-up

BACKGROUND

Obesity may represent a chronic low-grade inflammation, but there is a lack of long-term longitudinal studies. The aim of this longitudinal study was to evaluate the recurrence of periodontal disease in obese and normal weight patients submitted to scaling and root planing.

METHODS

The study included 22 patients who had received periodontal treatment 2 years previously, 13 obese and nine non-obese. The patients were evaluated for anthropometric measurements of body mass index, waist circumference, waist-to-hip ratio, and fat percentage through bioimpedance. The following periodontal parameters were recorded: visible plaque index (VPI), gingival bleeding index (GBI), probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP). The immunological evaluation analyzed the proinflammatory cytokines interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) in the gingival crevicular fluid (GCF).

RESULTS

Obese and normal weight patients did not differ in relation to the periodontal parameters of VPI, GBI, PD, CAL, or BOP 2 years after completion of the periodontal therapy. Sites with periodontitis in obese individuals showed higher levels of IL-6 and TNF-α in the gingival fluid (P <0.05).

CONCLUSION

Obese and normal weight individuals had similar periodontal behaviors, with low recurrence of the periodontal disease; however, obesity was related to increased inflammatory activity in gingival fluid, which may become a risk indicator for future greater recurrence of the disease in the presence of inadequate plaque control.

Periodontal complications with obesity

The purpose of this paper was to identify and summarize current evidence describing periodontal complications associated with obesity. Electronic searches supplemented with manual searches were carried out to identify relevant systematic reviews. Identification, screening, eligibility, and inclusion of studies were performed independently by two reviewers. A MeaSurement Tool to Assess systematic Reviews (AMSTAR) was used to assess the quality and risk of bias of the included reviews. From 430 titles and abstracts screened, 14 systematic reviews were considered as eligible for inclusion in this meta-review. Eight reviews reported on cross-sectional studies investigating the association of obesity and periodontal diseases, 4 included longitudinal studies, 5 addressed response to periodontal therapy, 5 reported on studies investigating biomarkers, and only 2 were related to pediatric population samples. Systematic review summaries in the various study design domains (cross-sectional, longitudinal and experimental) report that obese individuals are more likely to have periodontal diseases, with more severe periodontal conditions, than nonobese individuals, with cross-sectional evidence congruent with longitudinal studies showing that obesity or weight gain increases the risk of periodontitis onset and progression. Published research on the effect of obesity on responses to periodontal therapy, or systemic or local biomarkers of inflammation, is variable and therefore inconclusive based on the evidence currently available, which suggests that overweight/obesity contributes to periodontal complications independently of other risk factors, such as age, gender, smoking, or ethnicity. This evidence supports the need for risk assessments for individual patients to facilitate personalized approaches in order to prevent and treat periodontal diseases.