1000 Lives Plus



[pic] | |

|Oral health and systemic disease: a rapid review of the evidence |

|Author: Dr Mary Webb, Public Health Specialist |

|Date: 22 July 2011 |Version: 1 |

|Publication/ Distribution: |

|1000 Lives Dental Programme |

|Review Date: N/A |

|Purpose and Summary of Document: Work is being performed as part of the 1000 Lives Plus programme to establish the role of poor dental |

|hygiene and the development of periodontal disease (POD) on the outcomes of systemic diseases. The present document reports the results |

|of a rapid review of the literature on the association of oral health and systemic diseases. Evidence was particularly sought for a |

|causal role for POD. There was some evidence, mainly observational in type, to support an association with the diseases studied, but |

|evidence to support causality was lacking. Evidence was inconsistent on the most effective oral hygiene methods, but ongoing research may|

|clarify this issue. |

|Work Plan reference: HS 11 |

2011 Public Health Wales NHS Trust.

Material contained in this document may be reproduced without prior permission provided it is done so accurately and is not used in a misleading context.

Acknowledgement to Public Health Wales NHS Trust to be stated

Contents

| |Page |

|Key messages |3 |

| Introduction |6 |

|Research questions |6 |

|Methods |7 |

|3.1 Identifying existing and ongoing research |7 |

|Results |8 |

|4.1 Does poor oral health cause community and nosocomial acquired |8 |

|pneumonia in adults? | |

|4.1.1 Community acquired pneumonia |11 |

|4.1.2 Nursing home acquired pneumonia |12 |

|4.1.3 Nosocomial acquired pneumonia |13 |

|4.2 Is there an association between poor oral health and systemic |15 |

|disease | |

|4.2.1 Cardiovascular disease |16 |

|4.2.2 Hyperlipidaemia |19 |

|4.2.3 Obesity |19 |

|4.2.4 Stroke |20 |

|4.2.5 Hyperglycaemic control in diabetics |22 |

|4.2.6 Renal disease |24 |

|4.2.7 Adverse pregnancy outcomes [?] |25 |

|4.2.8 Rheumatoid arthritis |27 |

|4.2.9 Cancer |27 |

|4.2.10 Dementia |28 |

|5. References |29 |

|Appendices |39 |

Key messages

• There was a considerable amount of systematic review literature and meta-analyses of observational studies on the association of periodontal disease (POD) and systemic disease. Interpretation of the literature was hampered by the heterogeneity of the studies and the lack of a consistent definition of POD. Meta-analyses of observational studies can help explore potential associations, but such studies do not control for unmeasured confounders and adjust incompletely for measured confounders, hence such meta-analyses often contain substantial bias.

• Well designed randomised controlled trials are therefore required to establish a causal link between POD and systemic diseases and to determine the most effective methods for prevention of POD.

• The results of the available evidence, which were not from adequately powered RCTs, indicated that the link between POD and pneumonia could not be proved to be causal. Evidence for the most effective oral hygiene intervention to reduce the risk of pneumonia was inconsistent, but there was some evidence for tooth brushing and the use of chlorhexidine.

• Evidence was not found to demonstrate a link between POD and community acquired pneumonia.

• It is clear that aspiration of oropharyngeal commensals has some role in the aetiology of nursing home acquired pneumonia and it is possible that this allows for improved oral care as a therapeutic intervention. Adequately powered RCT data in this area is required.

• Pneumonia is a considerable problem in critically ill ventilated patients. A number of observational studies have suggested an association of POD and pneumonia in such patients. The evidence was inconsistent for the effectiveness of tooth brushing or the use of chlorhexidine solution. Research is being performed into the involvement of oral surgeons in intensive care.

• Evidence from large epidemiological datasets and meta-analyses of small-scale longitudinal studies and periodontal intervention studies showed that after adjustment for variables known to increase cardiovascular risk, there remained a significant increase in both incidence and prevalence of cardiovascular disease (CVD) in subjects with POD. The evidence was however not adequate to conclusively demonstrate causality.

• The evidence was inadequate to demonstrate conclusively an association of POD and hyperlipidaemia.

• There was some evidence for a biologically plausible role for obesity in the development of POD. However whether the relationship is causal needs to be assessed in further studies.

• There was a lack of consistent, good quality evidence to demonstrate an increased risk of stroke in persons with periodontitis compared with those without POD; the strongest association was for ischaemic stroke.

• Substantial evidence from systematic reviews and meta-analyses supported an association between POD and diabetes. However, the individual clinical trials that form the evidence base of these systematic reviews have low statistical power, are heterogeneous, and have poor internal validity. Periodontal therapy for the person with diabetes may have potential implications for public health. However, further larger, carefully conducted and reported studies are needed.

• There was a lack of good quality evidence to demonstrate an association between POD and renal disease.

• There was some evidence indicating an association between POD and adverse pregnancy outcomes.[?] A causal effect could not be established with the current available evidence. The maintenance of oral health is an important part of routine preventive care, and should be encouraged during and outside of pregnancy. Expert opinion concluded that it should be performed as part of routine preventive care, rather than specifically to improve pregnancy outcomes.

• There was a lack of consistent evidence to demonstrate an association of rheumatoid arthritis and POD.

• The most consistent risk for cancer and POD was found in oral and oesophageal cancers. There was some evidence suggesting a shared genetic risk for POD and cancer.

• There was limited evidence supporting a possible association between poor oral health and dementia. Additional studies of the relationships between oral health and cognition are required.

• Planned Cochrane reviews may help to clarify the role of POD in adverse outcomes and determine effective prevention methods.

Introduction

Poor oral health is a major public health problem worldwide and despite improvements in prevention and treatment oral conditions, such as gingivitis and periodontitis, are amongst the most prevalent microbial diseases in humans. [?]

Internationally there have been consensus reports on the association between poor oral health and systematic diseases and the importance of interventions to improve oral health. Epidemiological studies have linked poor oral health with a variety of conditions, such as cardiovascular disease, diabetes, adverse pregnancy outcomes, respiratory disease, stroke, rheumatoid arthritis, malignant disease, and obesity. [?] [?] [?] [?] [?] [?] [?] The European review by Williams et al. 2 concluded that oral health education should be considered part of the general healthy lifestyle messages to improve outcomes in the growing population of people who have for example, diabetes or are at risk for developing diabetes and/or cardiovascular disease. Most of the published literature on the associated health risks of poor oral heath is concerned with periodontal disease (POD). The term POD usually refers to gingivitis and periodontitis that are caused by pathogenic microflora in the biofilm or dental plaque. [?] If POD is a significant risk factor for systemic conditions then failure to address poor oral health will increase the risk of patients developing such conditions. 7

In the past three decades, marked advances have occurred in our understanding of the infectious agents of POD. Approximately 500 different bacterial entities and various human viruses are associated with dental microbial plaque. [?] Dental plaque biofilms containing periodontal pathogens give rise to POD, the manifestation of which is determined by the virulence of the bacteria, the host immunological response, and environmental factors such as smoking. [?]

Dental care services are one of the new clinical areas within the 1000 Lives Plus programme that is designed to improve patient outcomes throughout Wales. Public Health Wales was requested to perform a rapid review of the literature to determine the evidence for the effect of poor oral health on the development of systemic diseases and specifically acquired pneumonia in adults.

Research questions

• Does poor oral health cause community and nosocomial acquired pneumonia in adults?

• Is there an association between poor oral health and systemic diseases?

Methods

The two research questions in Section 2 were converted to structured questions for searching using the Population, Intervention, Comparison and Outcome (PICO) format. [?]

1 Identifying existing and ongoing research

Literature searches of Ovid Medline were performed by the British Dental Association Library between 1948 to March 2011. Supplementary searches were then performed by the author. It is well known that the classical databases for medical literature, such as Medline, do not adequately index all relevant literature. The reviewer used previously described validated methods that involved the use of meta-search engines and other databases for ‘high level’ searching to quickly identify relevant evidence. Search terms were kept broad to maximise retrieval of literature; details of the search strategies can be obtained from the author. The following databases were searched in June 2011, OVID online (Medline, Embase), PubMed, TRIP, Google, Google Scholar, NHS Evidence, UptoDate and SUMsearch. Papers were restricted to those in English, French, German and Spanish. Where information was available from good quality secondary sources this was used extensively to inform the document. It should be emphasised that the review is not a systematic review of primary studies. Every effort was made to avoid reviewer bias, but some selection bias of evidence is likely to be present

For critical appraisal, the methods recommended for use in the National Institute for Health and Clinical Excellence (NICE) Guideline Development Methods manual were used. [?] The quality of the evidence was graded using the NICE hierarchy of evidence and the quality checklists. It was particularly important for the review to consider causality with regard to POD and the reported systemic conditions. Leake has discussed the questions that one has to consider to establish a cause and effect relationship and the appraisal checklist for assessing causality was used, where applicable, for the relevant articles. [?] (Appendix 1)

Evidence was rejected if graded as poor quality, apart from where it was of Level 1 type (see Appendix 2 for explanation of evidence grading system) and was highly relevant to the question. The levels of evidence for the included papers are given after each reference in the reference section and in the Evidence Table (Appendix 3). Due to practical limitations a single reviewer performed the critical appraisal and data extraction.

4. Results

There were several good quality, up to date systematic reviews and meta-analyses relevant to the questions and these were used extensively to inform the present rapid review. 5 6 [?] [?]

4.1 Does poor oral health cause community and nosocomial acquired pneumonia in adults?

Pneumonia can be divided into two general categories, community acquired and nosocomial acquired. [?] These acquired pneumonias are important causes of morbidity and mortality despite improved antimicrobial therapy, supportive care, and prevention. Good quality systematic review evidence indicated that there has been increasing awareness from research studies that the oral cavity is an important reservoir for bacterial pathogens that cause respiratory disease. 4 15 16

In the first systematic literature review on respiratory diseases and oral health published in 2003, Scannapieco et al selected randomised controlled trials (RCTs), longitudinal, cohort, and case-control studies. The study populations included patients with any form of pneumonia or chronic obstructive pulmonary disease (COPD) and POD, as measured by assessments of gingival inflammation, probing depth, clinical attachment level, and/or radiographic bone loss, or oral hygiene indices. The summary statistics used to analyse the RCTs included weighted mean differences in rates of disease between control and intervention groups. For cohort studies that measured differences in rates of disease between groups with and without oral disease, weighted mean differences, relative risks, or odds ratios were compared. Of the initial 1,688 studies 21 (11 case control and cohort studies) (n= 1,413) and 9 RCTs (n= 1,759) were included. The results from the 30 studies demonstrated that the oral cavity may harbour bacteria for lower airway infections, especially for hospitalised patients and medically complex patients. 16

For the second systematic literature review, Azarpazhooh et al selected 19 studies. The authors concluded that there was evidence to support a fair association between pneumonia and oral health, drawing on evidence from well-designed cohort and case control studies.4 The authors identified dental decay and the presence of cariogenic bacteria in addition to periodontal pathogens as significant risk factors for aspiration pneumonia. 15

With regard to demonstrating a causal effect one recent review discussed the fact that relatively few RCTs have investigated the casual association between oral health and respiratory disease. In any such studies, it is extremely important to define the type of respiratory disease as well as the specific diagnostic criteria used for both the exposure measurement (periodontitis) and outcome measurement (respiratory infection). The authors concluded that the severity of POD appears to have a dose-response effect, although there was a lack of good quality studies demonstrating this relationship. [?]

Scannapieco and Ho [?] and Hayes et al. [?] found a tendency toward diminished pulmonary function with increasing clinical attachment loss. In a retrospective longitudinal study, Awano et al. [?] demonstrated that individuals with at least 10 teeth that had periodontal pockets greater than 4mm, presented with a higher incidence of mortality due to pneumonia than did those without any teeth with periodontal pockets, indicating that the greater the number of periodontally compromised teeth and consequently, the greater the quantity of oral bacteria, the greater the risk of mortality due to pneumonia. In the light of such evidence, Bágyi et al. [?] suggested that evaluation of the periodontal condition could be a method for identifying individuals who were at high risk of developing nosocomial pneumonia.

It is important in order to demonstrate causality of POD and pneumonia that prevention and/or treatment of POD results in a reduction in the occurrence of pneumonia. The following section discusses the evidence for prevention and treatment of POD and subsequent development of pneumonia.

Abe et al. [?] observed that elderly people who received professional oral hygiene care presented lower prevalence of respiratory pathogens such as Candida albicans than did individuals who did not receive such oral care. In another prospective study, it was noted that the mortality rate due to aspiration pneumonia was lower among elderly people who had been included in an oral care program than among those who had not participated in the programme. [?]

There was also systematic review evidence of interventional studies designed to measure the effectiveness of enhanced oral hygiene in relation to occurrence and/or progression of respiratory diseases. As part of the systematic review, Scannapieco et al completed a meta-analysis of combined data from five intervention trials and concluded that the oral hygiene intervention significantly reduced occurrence of pneumonia in institutionalised subjects. 16

In a review of 10 clinical research trials, Azarpazhooh et al. concluded that there was a good level of evidence that improved oral hygiene and the provision of professional oral care reduced the occurrence and/or progression of respiratory disease in high-risk elderly adults in intensive care units (ICUs) and nursing facilities. 15 No standard protocols for oral hygiene and/or professional oral care were identified through the research literature selected for review.

Two additional systematic reviews have been published regarding oral hygiene practices and respiratory diseases. In the first of the two reviews, Berry et al [?] focused on intensive oral health care for patients receiving mechanical ventilation. Although the authors found 55 published articles, they did not find high level evidence from either RCTs or systematic reviews, and as such, were limited in their evidence-based recommendations for clinical nursing practice. The authors recommended that standard protocols be developed and tested in multicentre trials in order to provide evidence on standard protocols for oral hygiene and professional care in hospitals and institutional settings.

In the second systematic review published in 2008, Sjogren et al selected 15 articles for analysis. [?] The oral hygiene measures studied were weekly conducted professional oral hygiene, or tooth brushing after every meal, alone, or in combination with daily 1% povidone iodine scrubbing of the pharynx. Although the authors noted a wide variety in the design and quality of the studies, they concluded that oral hygiene had positive preventive effects on reducing pneumonia and other respiratory infections in elderly patients who were either hospitalised or were nursing home residents. Approximately 1/10 cases of death from pneumonia among these individuals could be prevented by improving their oral hygiene; the number needed to treat being approximately.

It has been observed that the use of toothbrushes as a means of removing dental plaque amongst hospitalised individuals is more efficient than the use of foam swabs, especially when used at an appropriate frequency[?] [?]. Needleman et al. [?] performed a small RCT to investigate the effect of a powered toothbrush on colonisation of dental plaque by VAP associated organisms and dental plaque removal. Forty-six adults were recruited within 48h of admission. The test intervention was powered toothbrush cleaning and the control intervention sponge toothettes, both used four times per day for 2 min. Groups received 20 ml, 0.2% chlorhexidine mouthwash at each time point. The results showed a low prevalence of respiratory pathogens throughout with no statistically significant differences between groups. A highly statistically significantly greater reduction in dental plaque was produced by the powered toothbrush compared with the control treatment; mean plaque index at day 5, powered toothbrush 0.75 (95% confidence interval [CI] 0.53-1.00), sponge toothette 1.35 (95%CI 0.95-1.74), p=0.006. The total bacterial viable count was also highly statistically significantly reduced in the test group at day 5; Log10 mean total bacterial counts for powered toothbrush were 5.12 (95% CI 4.60-5.63), sponge toothette 6.61 (95% CI 5.93-7.28), p=0.002. The authors concluded that powered toothbrushes are highly effective for plaque removal in intubated patients in an intensive care unit (ICU) and should be further investigated for their ability to reduce VAP incidence and health complications.

Some authors have however, expressed concern that tooth brushing may carry an additional risk of bacteraemia. [?] [?]

Chlorhexidine, which is widely used for inhibiting the formation of the dental biofilm and controlling gingivitis and oral ulceration, leads to changes in bacterial retention and growth thereby resulting in reductions in bacterial colonisation on teeth. DeRiso et al. [?] tested oropharyngeal decontamination using 0.12% chlorhexidine digluconate in patients who would be undergoing surgical procedures. They obtained a reduction in the nosocomial infection rate of 65%. More recently, Munro et al. [?] examined the effects of brushing, the use of chlorhexidine, and a combination of both on the development of pneumonia associated with mechanical ventilation in 547 hospitalised patients. Their results showed that independent of brushing that 0.12% chlorhexidine reduced the incidence of pneumonia on the third day among individuals without infection at baseline. In another clinical trial, Scannapieco et al. [?] showed that topical application of chlorhexidine once or twice a day was effective against S. aureus in the dental biofilm of individuals undergoing mechanical ventilation, but that it did not significantly reduce the frequency of Gram-negative pathogens. However, these authors attributed this lack of association to the greater sensitivity of Staphylococcus aureus to chlorhexidine and to the small sample size of their study.

There is ongoing research into chlorhexidine mouth rinse as an adjunct treatment for gingival health in the form of a Cochrane protocol. [?]

A considerable number of hypotheses have been proposed to explain the possible role of oral bacteria in the pathogenesis of respiratory diseases, particularly for ventilated patients. 18 Firstly, dental plaque biofilm harbours both periodontal and pulmonary pathogens and this is of importance for patients in intensive care who are mechanically ventilated. [?] There was evidence that demonstrated that bacterial isolates from dental plaque are genetically indistinguishable from those cultured from bronchoalveolar lavage of ventilated patients. [?] [?] Secondly, enzymes associated with POD and the pathogens that cause it may facilitate adherence of respiratory pathogens to airways, destroy protective salivary pellicles, thereby reducing non-specific host defence mechanisms. [?]

4.1.1 Community acquired pneumonia

Community acquired pneumonia (CAP) is associated with conditions that increase the propensity for aspiration, such as alterations of consciousness due to stroke, dementia or alcohol abuse.

A study from the United Kingdom (UK) reported case-fatality rates of 5.6% in those aged 2.5 mm to 4.0 mm (p=0.230) for those who had clinical attachment loss >3.0 mm to 4.5 mm. [?]

A case control study of 1,137 men followed for up to 34 years indicated that there were 80 incidents of stroke or TIA. Periodontal bone loss was found to be the main link to stroke or TIA, (hazard ratio [HR] 3.52 95%CI 1.59-7.81 P=60 years) and investigated the relationship of POD to the self-reported history of stroke in the elderly by examining the data of the Third National Health and Nutrition Examination Survey (NHANES III). Owing to the fact that 1,563/5,123 subjects in the study were edentulous, and POD is a major cause of tooth loss, it was necessary to account for edentulousness in the statistical analysis to avoid bias. Therefore, a new index called the periodontal health status (PHS) index was developed to address this problem. Based on multiple logistic regression analysis of PHS with adjustment for age and tobacco use only, completely edentulous elderly adults (PHS Class 5) and partially edentulous (teeth in one arch) elderly adults with appreciable clinical attachment loss (PHS Class 4) were significantly more likely to have a history of stroke compared with dentate adults (teeth in both arches) without appreciable clinical attachment loss (PHS Class 1). When multiple logistic regression models were fit with adjustment of all significant confounders, no statistically significant association was found between PHS and stroke. Based on the results of this study, there was evidence of an association between cumulative POD based on PHS, and a history of stroke. However, it was unclear whether cumulative POD is an independent risk factor for stroke or a risk marker for the disease. [?]

In a Finnish study looking at the influence of genetics, the study population was comprised of a subpopulation of 392 community-living elderly people who participated in the population-based Kuopio 75+ study in Finland. After controlling for gender, age, basic education, diabetes, hypertension, smoking, alcohol consumption, physical activity, BMI, serum triglycerides and serum high-density lipoprotein (HDL) cholesterol, dentate persons had a slightly, non-significantly decreased likelihood of having a history of ischaemic stroke (positive predictive ration [PPR] 0.9 95% CI 0.2–2.8) when compared with edentulous subjects. The number of teeth was weakly and statistically non-significantly associated with a history of ischaemic stroke (PPR 1.02 95% CI 0.94–1.08). The limitations of this study are the use of cross sectional data, which means the temporal sequence between explanatory and outcome variables cannot be determined. [?]

4.2.5 Hyperglycaemic control in diabetes

There is now a growing body of research indicating a bidirectional relationship between POD and diabetes. Poor glycaemic control in diabetes may be a risk factor for POD and POD could have an adverse effect on glycaemic control. 5

In 2004 Taylor and Borgnakke identified POD as a possible risk factor for poor metabolic control in people with diabetes mellitus (DM). [?] The review examined 42 observational studies and found that overall there was consistent evidence of greater prevalence, incidence, severity, extent, or progression of POD in individuals with diabetes. The evidence also supported a bi-directional relationship between POD and diabetes. In addition, a dose-response relationship provided some support for a cause-effect relationship. The review examined 25 observational studies and found that there was insufficient evidence to conclude that there is an association between tooth loss, coronal or root caries, and diabetes. The authors concluded that the evidence supported oral examinations and POD prevention and treatment for persons with diabetes.

A 2006 meta-analysis examined the extent and severity of POD between diabetics and non-diabetics. [?] The meta-analysis was based on international studies including 18 comparative cross sectional studies, 3 prospective cohort studies, and baseline data from 2 clinical trials comparing oral hygiene, gingival and periodontal status. The study showed that the severity of POD was significantly higher in diabetics compared with non-diabetics, but the extent of the disease was the same in both groups. The difference in the average of plaque index between diabetics and non-diabetics was statistically significant at 0.218 (95% CI, 0.098-0.330); the gingival index was 0.147 (95% CI, 0.012-0.281); probing pocket depth was 0.346 (95% CI, 0.194-0.498). Clinical attachment loss, bleeding on probing, and the calculus index were not significant.

A meta-analysis systematically reviewed the studies on the association between DM and destructive POD. Of the 2440 identified studies, 49 cross-sectional and 8 longitudinal studies met the inclusion criteria. Twenty-seven/49 cross-sectional studies included in the review detected more POD in diabetic subjects compared with non-diabetic subjects. The greater risk of POD progression was associated with type 2 DM, and one study associated DM with response to periodontal therapy. Methodological flaws in the majority of studies included inadequate control for confounders, insufficient statistical analysis and lack of information about sampling design. Random effect models showed a significant association with clinical attachment level (mean difference = 1.00 95%CI 0.15-1.84) and periodontal pocket depth (mean difference = 0.46 95%CI 0.01- 0.91) between type 2 diabetics and non-diabetics. The authors concluded that type 2 DM can be considered a risk factor for periodontitis. More studies are needed however, to confirm the harmful effects of type 1 DM on POD. 63

Another meta-analysis investigated the link between POD and glycaemic control in diabetics. Twenty-five studies, involving 976 subjects, were included. Of these, nine studies, involving a total of 485 patients, were controlled trials and were included in a meta-analysis. The standardised mean difference in HbA1c with POD therapy was 0.46 (95% CI 0.11-0.82). The findings suggested that periodontal treatment could lead to a significant 0.79% (95% CI 0.19-1.40) reduction in HbA1c level. The results should however be viewed with caution because of methodological problems with some of the included studies. Another subsequent meta-analysis suggested improvement of glycaemic control in diabetic patients, but again there were problems with heterogeneity of the studies. 62

A 2010 Cochrane review investigated the relationship between periodontal treatment and glycaemic control in people with diabetes and aimed to identify an appropriate future strategy for such therapy. Seven studies were included and 3 studies had results pooled into a meta-analysis. The effect for the mean percentage difference in HbA1c for scaling/root planing and oral hygiene (+/- antibiotic therapy) versus no treatment/usual treatment after 3/4 months was -0.40% (95% CI fixed effect -0.78%-0.01%), representing a statistically significant reduction in HbA1c (P = 0.04) for scaling/root planing. One study was assessed as being at a low risk of bias with the other two at moderate to high risk. A subgroup analysis examined studies without adjunctive antibiotics -0.80% (one study: 95% CI -1.73%-0.13%; P = 0.09), with adjunctive antibiotics in the test group -0.36% (one study 95% CI -0.83%-0.11%, P = 0.14), and with antibiotics in both test and control groups after 3/4 months -0.15% (one study 95% CI -1.04%-0.74%, P = 0.74). The authors concluded that there is some evidence of improvement in metabolic control in people with diabetes, after treating POD. There were however, few studies available and individually these lacked the power to detect a significant effect. Most of the participants in the study had poorly controlled Type 2 DM with little data from randomised trials on the effects on people with Type 1 DM. [?]

4.2.6 Renal disease

Chronic inflammation contributes to both coronary heart disease and chronic kidney disease (CKD) occurrence and progression and POD adds to the cumulated chronic systemic inflammatory burden. [?] A bidirectional relationship between CKD and POD is plausible and preliminary modelling studies have demonstrated a bidirectional relationship between CKD and POD. Data from 11,211 adults were used in multivariable logistic regression models. In 2 separate models POD score and POD were associated with CKD when simultaneously adjusting for 14 other factors. [?]

It appeared however, from the literature that evidence for the association of POD with CKD consisted of a small amount of observational Level 3 evidence studies; RCTs were not found. There was some observational evidence indicating that POD adversely affects the survival of patients with end stage renal disease (ESRD) who are on dialysis. 87 The same study also found a lack of good quality evidence to recommend POD treatment for patients with acute or chronic renal disease.

In a small study of 168 adult patients with ESRD, 100 patients had mild or no POD but the remaining 68 had moderate-to-severe disease defined as 2 or more teeth with at least 6 mm of inter-proximal attachment loss. At baseline, the proportion of males was significantly lower in the moderate-to-severe group. Compared with mild or no POD, moderate-to-severe disease was significantly associated with death from cardiovascular causes. Adjustment for age, gender, centre and length of time on dialysis, smoking status, and history of DM or hypertension did not decrease the strength of this association. The authors concluded that there is a need for larger studies to confirm the connection between POD and outcomes in CKD, together with intervention trials to determine if treating periodontitis reduces coronary vascular disease mortality in dialysis patients. Another study suggested that POD is associated with mortality in ESRD receiving maintenance dialysis but confounding was present in this study and the results require confirmation. [?]

The prevalence of metabolic syndrome was also reported in one study of 253 haemodialysis patients. Metabolic syndrome was present in 65.1% among individuals (n = 149) with moderate-severe periodontitis, 54.5% among individuals (n = 55) with mild periodontitis and 36.7% among individuals (n = 49) without periodontitis. After adjustment of confounders, patients with moderate-severe periodontitis were 2.736 [95% CI 1.293–5.790] times more likely to develop metabolic syndrome than were those without periodontitis. In addition, the OR for metabolic syndrome was 1.561 (95% CI 1.121–2.166) per score of gingival inflammation severity and 1.724 (95% CI 1.135–12.615) per score of dental plaque burden.

Serum samples from patients in the Dental Atherosclerosis Risk in Communities (ARIC) study was used to study antibodies to periodontal organisms in patients with decreased renal function. The results demonstrated elevated immunoglobulin G (IgG) to periodontal pathogens was significantly associated with impaired renal function. The results require confirmation in prospective studies with attempts to reduce confounding. [?]

7. Adverse pregnancy outcomes

Several studies have shown the extent and severity of POD as a risk factor for adverse pregnancy outcomes. 59 60 61 One report from Canada reviewed the published systematic reviews and meta-analyses published up to 2006 that examined the effect of oral disease on pregnancy outcomes. 6

A systematic review of twelve studies concluded that POD may be a risk factor for pre-term/low birth weight (PT/LBW) and there was preliminary evidence suggesting that periodontal intervention may reduce adverse pregnancy outcomes. [?] The review included six case control studies, three cross-sectional and longitudinal studies, and three intervention studies. Due to study heterogeneity, meta-analysis was not possible.

A 2004 review on this topic included nine studies: four case control, two prospective. The review concluded that POD may act as a risk factor for PT/LBW.[?]

A 2005 meta-analysis of five observational studies

concluded that POD in the pregnant mother significantly increased the risk of PT/LBW. This meta-analysis included two case-control studies and three prospective cohort studies. These studies showed that pregnant women with POD have an adjusted OR of 4.28 (95% CI, 2.62-6.99, P= ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download