Periodontal disease and risk of subsequent cardiovascular disease in U.S. male physicians

Relationship between self-reported periodontal status and skeletal bone mineral density in Japanese postmenopausal women

OBJECTIVE

Several investigators have linked periodontal disease progression and low skeletal bone mineral density in postmenopausal women. However, little is known about whether self-reported periodontal status is the reflection of skeletal bone mineral density. We investigated whether self-reported poor periodontal status is associated with low skeletal bone mineral density in postmenopausal women.

DESIGN

Relationships among self-reported periodontal status, number of teeth remaining, and bone mineral density of the lumbar spine and the femoral neck were evaluated in 253 Japanese postmenopausal women (mean +/- SD, 56.6 +/- 7.7) recruited from the patients who visited our clinic for bone mineral assessment between 1997 and 2003. Self-reported periodontal symptoms included gingival swelling, gingival bleeding, purulent discharge, and tooth mobility at the time of bone mineral assessment.

RESULTS

Analysis of covariance adjusted for age, height, weight, years since menopause, duration of estrogen use, and regular oral care revealed that subjects without periodontal symptoms had significantly higher BMD of the lumbar spine than did those with periodontal symptoms (mean +/- SEM, 0.962 +/- 0.014 vs 0.921 +/- 0.013; P = 0.038); however, there were no significant differences in the number of remaining teeth and bone mineral density of the femoral neck between them. The odds of low spine bone mineral density in subjects with periodontal symptoms was 2.01 (95% CI = 1.15 to 3.50).

CONCLUSION

Our results suggest that self-reported poor periodontal status may be associated with low bone mineral density of the lumbar spine in postmenopausal women.

Periodontal disease and mortality in type 2 diabetes

OBJECTIVE

Periodontal disease may contribute to the increased mortality associated with diabetes.

RESEARCH DESIGN AND METHODS

In a prospective longitudinal study of 628 subjects aged > or =35 years, we examined the effect of periodontal disease on overall and cardiovascular disease mortality in Pima Indians with type 2 diabetes. Periodontal abnormality was classified as no or mild, moderate, and severe, based on panoramic radiographs and clinical dental examinations.

RESULTS

During a median follow-up of 11 years (range 0.3-16), 204 subjects died. The age- and sex-adjusted death rates for all natural causes expressed as the number of deaths per 1,000 person-years of follow-up were 3.7 (95% CI 0.7-6.6) for no or mild periodontal disease, 19.6 (10.7-28.5) for moderate periodontal disease, and 28.4 (22.3-34.6) for severe periodontal disease. Periodontal disease predicted deaths from ischemic heart disease (IHD) (P trend = 0.04) and diabetic nephropathy (P trend < 0.01). Death rates from other causes were not associated with periodontal disease. After adjustment for age, sex, duration of diabetes, HbA1c, macroalbuminuria, BMI, serum cholesterol concentration, hypertension, electrocardiographic abnormalities, and current smoking in a proportional hazards model, subjects with severe periodontal disease had 3.2 times the risk (95% CI 1.1-9.3) of cardiorenal mortality (IHD and diabetic nephropathy combined) compared with the reference group (no or mild periodontal disease and moderate periodontal disease combined).

CONCLUSIONS

Periodontal disease is a strong predictor of mortality from IHD and diabetic nephropathy in Pima Indians with type 2 diabetes. The effect of periodontal disease is in addition to the effects of traditional risk factors for these diseases.

The association between tooth loss and coronary heart disease in men and women

OBJECTIVES

This paper evaluates the relation of tooth loss to incidence of coronary heart disease in two large cohort studies.

METHODS

Participants included 41,407 men and 58,974 women free of any cardiovascular diseases at baseline. We recorded 1,654 incident coronary heart disease events (562 fatal events) among men during 12 years of follow-up and 544 events (158 fatal events) among women during 6 years of follow-up.

RESULTS

After controlling for important cardiovascular risk factors, compared to men with 25-32 teeth at baseline, men with 0-10 teeth had a significantly higher risk of coronary heart disease (relative risk [RR]= 1.36; 95 percent confidence interval [CI]=1.11, 1.67). The relative risk increased to 1.79 (95% CI=1.34, 2.40) when limited to fatal events. Women with 0-10 teeth were also at increased risk of coronary heart disease compared to women with 25-32 teeth (RR=1.64; 95% CI=1.31, 2.05). The association was similar for fatal events (RR= 1.65; 95% CI=1.11, 2.46). The association between number of teeth and incidence of coronary heart disease was similar between men with and without a history of periodontal disease, and there was no significant association between tooth loss during follow-up and coronary heart disease.

CONCLUSIONS

This study showed a significant association between number of teeth at baseline and risk of coronary heart disease and the mechanisms to explain this association should be further clarified.

Oral health, atherosclerosis, and cardiovascular disease

During the last two decades, there has been an increasing interest in the impact of oral health on atherosclerosis and subsequent cardiovascular disease (CVD). The advent of the inflammation paradigm in coronary pathogenesis stimulated research in chronic infections caused by a variety of micro-organisms-such as Chlamydia pneumoniae, Helicobacter pylori, and cytomegalovirus-as well as dental pathogens, since these chronic infections are thought to be involved in the etiopathogenesis of CVD by releasing cytokines and other pro-inflammatory mediators (e.g., C-reactive protein [CRP], tumor necrosis factor [TNF-alpha]) that may initiate a cascade of biochemical reactions and cause endothelial damage and facilitate cholesterol plaque attachment. Yet, due to the multi-factorial nature of dental infection and CVD, confirming a causal association is difficult, and the published results are conflicting. The main deficit in the majority of these studies has been the inadequate control of numerous confounding factors, leading to an overestimation and the imprecise measurement of the predictor or overadjustment of the confounding variables, resulting in underestimation of the risks. A meta-analysis of prospective and retrospective follow-up studies has shown that periodontal disease may increase the risk of CVD by approximately 20% (95% confidence interval [CI], 1.08-1.32). Similarly, the reported risk ratio between periodontal disease and stroke is even stronger, varying from 2.85 (CI 1.78-4.56) to 1.74 (CI 1.08-2.81). The association between peripheral vascular disease and oral health parameters has been explored in only two studies, and the resultant relative risks among individuals with periodontitis were 1.41 (CI 1.12-1.77) and 2.27 (CI 1.32-3.90), respectively. Overall, it appears that periodontal disease may indeed contribute to the pathogenesis of cardiovascular disease, although the statistical effect size is small.

Periodontal diseases and the risk of coronary heart and cerebrovascular diseases: a meta-analysis

BACKGROUND

This meta-analysis was conducted to examine the relationship between periodontal diseases and coronary heart diseases (CHD) and cerebrovascular diseases (CVD) in observational studies.

METHODS

This study was based on seven cohort studies and four studies of other designs that met prestated inclusion criteria. Information on study design, year of publication, study location, sample size, study population, participant characteristics, measurement of risk factors, exposure and outcome measures, matching, controlling for confounders, and risk estimates was abstracted independently by two investigators using a standard protocol.

RESULTS

Subjects with periodontitis had an overall adjusted risk of CHD that was 1.15 times (95% confidence interval [CI]: 1.06 to 1.25; P = 0.001) the risk for healthy subjects. There was no heterogeneity among the studies in the overall relative risk estimate (P = 0.472). As compared to healthy subjects, those with periodontitis had an overall adjusted relative risk of CVD of 1.13 (95% CI: 1.01 to 1.27; P = 0.032).

CONCLUSIONS

Findings indicated that periodontal infection increases the risk of CHD and CVD. However, this meta-analysis provided no evidence for the existence of strong associations between periodontitis and CHD and CVD. Larger and better-controlled studies involving socially homogeneous populations and measuring specific periodontal pathogens are required to identify a definite association between periodontal disease and the risk of coronary heart disease and cerebrovascular disease.

Relationship of periodontal disease and tooth loss to prevalence of coronary heart disease

BACKGROUND

Studies relating periodontal disease to coronary heart disease (CHD) have provided equivocal results using tooth loss and/or clinical signs of periodontal disease as measures of periodontal exposure.

METHODS

The purpose of this cross-sectional study was to evaluate the relationship of tooth loss and periodontitis to prevalent CHD at the Atherosclerosis Risk in Communities (ARIC) visit 4 using both tooth loss and clinical signs of disease in a population-based sample of 8,363 men and women aged 52 to 75 years from four U.S. communities. Each subject participated in a complete periodontal examination, assessment of missing teeth, assessment of prevalent CHD, and a number of laboratory tests and questionnaires. High attachment loss was defined as > or = 10% of sites with attachment loss > 3 mm and high tooth loss was defined as fewer than 17 remaining teeth.

RESULTS

Individuals with both high attachment loss and high tooth loss (odds ratio [OR] 1.5, 95% confidence interval [CI] 1.1 to 2.0) and edentulous individuals (OR 1.8, CI 1.4 to 2.4) had elevated odds of prevalent CHD compared to individuals with low attachment loss and low tooth loss, while controlling for a number of traditional risk factors for CHD.

CONCLUSIONS

These results suggest that tooth loss and periodontal disease are associated with prevalent CHD, but only when both are present. The weaker relationships between periodontal disease and CHD that have been found among older adults may be due to older adults having fewer teeth. Future longitudinal studies should be designed to ascertain the cause of tooth loss during follow-up.

Periodontitis and atherogenesis: causal association or simple coincidence?

OBJECTIVES

The aim of this study was to assess the systemic effects of treating severe widespread periodontitis in a population of otherwise healthy individuals by examining treatment associated changes in markers of inflammation that are also implicated in cardiovascular atherosclerotic diseases. The potential impact of specific polymorphisms in cytokine genes known to influence both periodontitis and cardiovascular diseases was also examined.

MATERIALS AND METHODS

A convenience sample of patients affected with severe generalised periodontitis was enrolled into a prospective single blind longitudinal intervention trial with a 6 months follow-up. Serum C-reactive protein (CRP) and interleukin-6 (IL-6) levels were assessed by high-sensitivity assays. Serological and clinical periodontal parameters were evaluated at baseline, 2 and 6 months after completion of non-surgical periodontal therapy.

RESULTS

In the 94 subjects that completed this pilot trial improvements in all clinical periodontal parameters were achieved. These were accompanied with significant reductions in serum IL-6 and CRP concentrations. In a multivariate model, serum CRP levels were significantly associated with the outcome of periodontal treatment after correcting for potential covariates (age, body mass index, gender, smoking) and polymorphisms in the IL-6 (-174 C/G) and IL-1A (-889) genes. A median decrease in serum CRP of 0.5 mg/l (95% CI 0.4-0.7 mg/l) was observed 6 months after completion of periodontal therapy in this population. Subjects with above average response to periodontal therapy (<30 residual pockets and <30% of sites bleeding on probing) accounted for the observed improvement in serum CRP.

CONCLUSIONS

Control of periodontitis, achieved with non-surgical periodontal therapy, significantly decreased serum mediators and markers of acute phase response. The significance of the serum response was associated with the half of the population that responded better to non-surgical periodontal therapy. The results of this pilot study indicate that severe generalised periodontitis causes systemic inflammation. This is consistent with a causative role of periodontitis in atherogenesis.

Relationship Between Electrocardiographic Abnormalities and Periodontal Disease: The Hisayama Study

BACKGROUND

Recent studies have suggested a relationship between periodontitis and cardiovascular disease (CVD). This study investigated the relationship between periodontitis and electrocardiographic (ECG) abnormalities, which are known predictors of CVD.

METHODS

We examined the periodontal status of 1,111 residents of Hisayama Town, Fukuoka, Japan. Nine hundred fifty-seven (957) subjects (374 males, 583 females) with > or = 10 teeth and without a medical history of CVD were included in the analysis. Probing depth (PD) and clinical attachment level (CAL) were measured on two randomly selected quadrants, one maxillary and one mandibular. A 12-lead ECG was recorded using a standard electrocardiograph. ECG abnormalities included left ventricular hypertrophy (Minnesota code 3-1) and ST depression (4-1, 2, 3). The relation of periodontal condition and ECG abnormalities was assessed with logistic regression analysis.

RESULTS

Univariate analysis revealed that mean probing depth, mean attachment loss, number of teeth, and plaque index were significantly associated with ECG abnormalities, as well as with known risk factors of CVD. In multivariate analysis, the subjects with deep pockets (mean probing depth > or = 2 mm) had an increased risk for ECG abnormalities (odds ratio [OR] = 1.6; 95% confidence interval [CI] = 1.01 to 2.50) compared to the subjects with mean PD < 2 mm. Subjects with severe attachment loss (mean CAL > or = 2.5 mm) had also significant risk for ECG abnormalities (OR = 1.7; 95% CI = 1.07 to 2.67) compared to those whose mean CAL was < 2.5 mm.

CONCLUSION

This study clearly shows the relationship between periodontitis and ECG abnormalities, which are important predictors of CVD.

The association of gingivitis and periodontitis with ischemic stroke

OBJECTIVES

The aim of this study was to assess the associations of different periodontal parameters with cerebral ischemia.

METHODS

In a case-control study, 303 consecutive patients with ischemic stroke or transient ischemic attack, and 300 representative population controls received a complete clinical and radiographic dental examination. Patients were examined on average 3 days after ischemia. The individual mean clinical attachment loss measured at four sites per tooth was used as indicator variable for periodontitis.

RESULTS

Patients had higher clinical attachment loss than population (p<0.001). After adjustment for age, gender, number of teeth, vascular risk factors and diseases, childhood and adult socioeconomic conditions and lifestyle factors, a mean clinical attachment loss >6 mm had a 7.4 times (95% confidence interval 1.55-15.3) a gingival index >1.2 a 18.3 times (5.84-57.26) and a radiographic bone loss a 3.6 times (1.58-8.28) higher risk of cerebral ischemia than subjects without periodontitis or gingivitis, respectively.

CONCLUSION

Periodontitis is an independent risk factor for cerebral ischemia and acute exacerbation of inflammatory processes in the periodontium might be a trigger for the event of cerebral ischemia.

Poor oral health is associated with coronary heart disease and elevated systemic inflammatory and haemostatic factors

OBJECTIVES

To assess the relationship between poor oral health and coronary heart disease (CHD) and systemic inflammatory and haemostatic factors in an Italian population.

MATERIAL AND METHODS

The study population consisted of 63 males aged 40-65 years with proven CHD and 50 controls matched for age, geographic area, and socioeconomic status. A detailed description of their oral status was given using four different dental indices (total dental index (TDI), panoramic tomography score, clinical periodontal sum score (CPSS), and clinical and radiographic sum score (CRSS)). Blood samples were taken for measurement of the following CHD risk factors: serum total cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and glucose; a series of systemic markers of inflammation (C-reactive protein, leucocytes, fibrinogen, homocysteine) and a series of haemostatic factors (von Willebrand factor, fibrin D-dimer, prothrombinic fragment F1.2, plasminogen activator inhibitor type I (PAI-1), and serum antibodies) against oxidized LDL (anti-Ox-LDL).

RESULTS

Multiple logistic regression adjusted for all risk factors for CHD showed statistically significant relationships (p<0.01) between all dental indices and CHD. Significant relationships (p always <0.01) were found between CPSS and CRSS and leucocyte count. Significant relationships (p always <0.05) were also found between TDI and the von Willebrand factor, and between CPSS and the von Willebrand factor, anti-Ox-LDL, and PAI-1.

CONCLUSIONS

The present study suggests an association between poor oral status and CHD, and provides evidence that inflammatory and haemostatic factors could play an important role in this association.

Analysis of periodontal risk profiles in adults with or without a history of myocardial infarction

BACKGROUND

An association between periodontitis and cardiovascular diseases has been suggested.

AIMS

To study whether a combination of clinical variables in a functional risk diagram enhanced the ability to differentiate between subjects with or without an immediate history of acute myocardial infarction (AMI).

MATERIAL AND METHODS

A functional periodontal pentagon risk diagram (PPRD) with five periodontal risk vectors was created. The surface of individual PPRDs was calculated using data from 88 subjects with recent AMI and 80 matched control subjects with no history of AMI.

RESULTS

Age, gender, number of remaining teeth (mean value: 21.1 versus 21.6 teeth), smoking status, and pocket probing depth (PPD) distribution did not differ by group. Gingival recession was greater in control subjects (mean difference: 5.7, SD: +/- 1.9, p<0.01, 95% CI: 1.8-9.6). Bone loss > or = 4.0 mm was at all levels studied was significantly greater in subjects with AMI and bone loss > or = 50% (> or = 4 mm) was the best individual predictor of AMI (beta = 2.99, p < 0.000, 95% CI: 7.5-53.4). Only PPRD scores were associated with AMI status when factors not included in the PPRD were studied (beta = 22.1, SE: 5.9, p < 0.0001, 95% CI: 10.3-33.7). The best association between AMI status and study variables was the combination of > or = 4 mm of bone loss > or = 50%, proportion of bleeding on probing (%BOP), %PPDs > or = 6 mm, and tooth loss (Nagelkirke r2 = 0.46).

CONCLUSIONS

The combination of five periodontal parameters in a PPRD added predictive value, suggesting that comprehensive data should be used in studies of associations between periodontitis and heart diseases. Radiographic evidence of bone loss was the best individual parameter.

The Short-Term Effects of Treatment of Chronic Periodontitis on Circulating Levels of Endotoxin, C-Reactive Protein, Tumor Necrosis Factor-α, and Interleukin-6

BACKGROUND

The acute-phase response involves molecules including tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and C-reactive protein (CRP). This study aimed to determine whether subgingival scaling resulted in rapid changes in plasma concentrations of these molecules.

METHODS

Twenty-three non-smoking adults with chronic periodontitis received subgingival scaling for 60 minutes. Venous blood samples were taken at 0, 15, 30, 60, and 120 minutes. TNF-alpha and IL-6 were assayed from all samples and CRP from the baseline and final samples. Lipopolysaccharide (LPS) was assayed at 0, 15, and 30 minutes using limulus lysate assay (LAL) and EndoCAb Ig assays.

RESULTS

LPS assays were suggestive of a transient low-grade bacteremia, but changes in LPS approaching significance (P=0.061) were seen with LAL only. There was a significant increase in circulating TNF-alpha (P=0.0387) and IL-6 (P<0.0001), and the degree of change in TNF-alpha was correlated with the severity of periodontal breakdown (P=0.001). There was also a significant correlation between levels of IL-6 and TNF-alpha (P<0.001).

CONCLUSIONS

Chronic periodontitis patients undergoing an episode of subgingival scaling show a significant elevation in circulating TNF-alpha and IL-6. This may account for anecdotal reports of pyrexia following treatment and may be significant in terms of the relationship between periodontal disease, bacteremia, and cardiovascular disease.

Periodontal Disease as a Risk Factor for Ischemic Stroke

BACKGROUND AND PURPOSE

Chronic infectious diseases may increase the risk of stroke. We investigated whether periodontal disease, including periodontitis and gingivitis, is a risk factor for cerebral ischemia.

METHODS

We performed a case-control study with 303 patients examined within 7 days after acute ischemic stroke or transient ischemic attack, 300 population controls, and 168 hospital controls with nonvascular and noninflammatory neurological diseases. All subjects received a complete clinical and radiographic dental examination. The individual mean clinical attachment loss measured at 4 sites per tooth served as the main indicator for periodontitis.

RESULTS

Patients had higher clinical attachment loss than population (P<0.001) and hospital (P=0.010) controls. After adjustment for age, sex, number of teeth, vascular risk factors and diseases, childhood and adult socioeconomic conditions, and lifestyle factors, the risk of cerebral ischemia increased with more severe periodontitis. Subjects with severe periodontitis (mean clinical attachment loss >6 mm) had a 4.3-times-higher (95% confidence interval, 1.85 to 10.2) risk of cerebral ischemia than subjects with mild or without periodontitis (<or=3 mm). Severe periodontitis was a risk factor in men but not women and in younger (<60 years) but not older subjects. Periodontitis increased the risk of cerebral ischemia caused by large-artery atherosclerosis, cardioembolism, and cryptogenic etiology. Gingivitis and severe radiologic bone loss were also independently associated with the risk of cerebral ischemia, whereas caries was not.

CONCLUSIONS

Our study indicates that periodontal disease, a treatable condition, is an independent risk factor for cerebral ischemia in men and younger subjects.

Correlation study on oral health and electrocardiogram abnormalities

The purpose of this study was to investigate the association between periodontal conditions and electrocardiogram test results that were obtained to screen for coronary heart disease risk factors. The present study included a total of 578 subjects who underwent annual medical check-ups at the Total Health Care Center in Otsu, Shiga Prefecture, Japan. To calculate the odds ratios for the electromyography abnormalities, we performed a logistic regression analysis for the oral examination, electrocardiogram, and blood analysis data. The crude odds ratio was obtained by a logistic regression analysis of age, sex, number of missing teeth, number of filled teeth, simplified oral hygiene index, community periodontal index, and blood analysis factors and results indicated there was a statistically significant correlation with the prevalence of electrocardiogram abnormalities. However, electrocardiogram abnormalities have a strong correlation with demographic factors such as sex and age. Therefore the experimental factors representing oral status were reexamined after the odds ratios were adjusted for age and sex. As a result of this adjustment, the new odds ratios that were determined indicated that there were no correlations between the oral factors and the prevalence of electrocardiogram abnormalities.

Inflammation and infections as risk factors for ischemic stroke

BACKGROUND

Inflammatory processes have fundamental roles in stroke in both the etiology of ischemic cerebrovascular disease and the pathophysiology of cerebral ischemia. We summarize clinical data on infection and inflammation as risk or trigger factors for human stroke and investigate current evidence for the hypothesis of a functional interrelation between traditional risk factors, genetic predisposition, and infection/inflammation in stroke pathogenesis.

SUMMARY OF REVIEW

Several traditional vascular risk factors are associated with proinflammatory alterations, including leukocyte activation, and predispose cerebral vasculature to thrombogenesis on inflammatory stimulation. Furthermore, accumulation of inflammatory cells, mainly monocytes/macrophages, within the vascular wall starts early during atherogenesis. During later disease stages, their activation can lead to plaque rupture and thrombus formation, increasing stroke risk. Inflammatory markers (eg, leukocytes, fibrinogen, C-reactive protein) are independent predictors of ischemic stroke. Chronic infections (eg, infection with Chlamydia pneumoniae or Helicobacter pylori) were found to increase the risk of stroke; however, study results are at variance, residual confounding is not excluded, and causality is not established at present. In case-control studies, acute infection within the preceding week was a trigger factor for ischemic stroke. Acute and exacerbating chronic infection may act by activating coagulation and chronic infections and may contribute to atherogenesis. Genetic predisposition of the inflammatory host response may be an important codeterminant for atherogenesis and stroke risk.

CONCLUSIONS

Inflammation contributes to stroke risk via various interrelated mechanisms. Infectious diseases, traditional risk factors, and genetic susceptibility may cooperate in stimulating inflammatory pathways. Final proof of a causal role of infectious/inflammatory mechanisms in stroke pathogenesis is still lacking and will require interventional studies.

Oral health indicators poorly predict coronary heart disease deaths

Several earlier studies have suggested that development of coronary heart disease (CHD) is causally related to oral infections. The aim of this study was to investigate the association between oral health indicators and CHD deaths. Out of a nationally representative sample, 6527 men and women aged 30-69 years participated in the health examination with a dental check. Detailed oral health data included caries, periodontal and dental plaque status, presence of remaining teeth, and various types of dentures. Over a mean 12-year follow-up, persons dying of CHD were older and more often smoked, had hypertension, hypercholesterolemia, diabetes, and only a basic education compared with other persons. In univariate analyses, several oral health indicators were associated with CHD deaths. Adjustment for the established CHD risk factors reduced all these associations to statistical non-significance. The associations between oral health indicators and CHD are mostly explained by confounding factors, particularly those relating to health behavior.

Relationship between periodontal disease, tooth loss, and carotid artery plaque: the Oral Infections and Vascular Disease Epidemiology Study (INVEST)

BACKGROUND AND PURPOSE

Chronic infections, including periodontal infections, may predispose to cardiovascular disease. The present study investigates the relationship of periodontal disease and tooth loss with subclinical atherosclerosis.

METHODS

We enrolled 711 subjects with a mean age of 66+/-9 years and no history of stroke or myocardial infarction in the Oral Infections and Vascular Disease Epidemiology Study. Subjects received a comprehensive periodontal examination, extensive in-person cardiovascular disease risk factor measurements, and a carotid scan using high-resolution B-mode ultrasound. Regression models were adjusted for conventional risk factors (age, sex, smoking, diabetes, systolic blood pressure, low- and high-density lipoprotein cholesterol, race-ethnicity, education, physical activity) and markers of cultural background, healthy lifestyle, and psychosocial health.

RESULTS

Measures of both current and cumulative periodontitis became more severe as tooth loss increased. A significant association was observed between tooth loss levels and carotid artery plaque prevalence. Among those with 0 to 9 missing teeth, 46% had carotid artery plaque, whereas among those with >or=10 missing teeth, carotid artery plaque prevalence was approximately 60% (P<0.05).

CONCLUSIONS

Our data suggest that tooth loss is a marker of past periodontal disease in this population and is related to subclinical atherosclerosis, thereby providing a potential pathway for a relationship with clinical events.

Is periodontitis associated with an increased risk of coronary heart disease and preterm and/or low birth weight births?

The objective of this systematic review was to determine whether periodontal disease is associated with an increased risk for coronary heart disease (CHD) and preterm and/or low birth weight deliveries (PLBW). A literature search was performed to identify cross-sectional, case-control, and cohort studies as well as clinical trials addressing different aspects of periodontal disease (clinical, microbial, immunological) and clinical outcomes of CHD or PLBW. The periodontitis-CHD association was evaluated in eight cohort, four case-control- and four cross-sectional studies. Meta-analysis was not performed due to the extensive heterogeneity of the studies, particularly with regard to periodontitis measures, which varied from full mouth probing assessments to questionnaires. Percentage-wise, 50% of the cohort studies (4/8), 75% of the case-control studies (3/4) and 50% of the cross-sectional studies (2/4) reported a significant association between clinical measures of periodontitis and CHD (excess risk ranged from 0 to 3.3-fold). The periodontitis-PLBW association was evaluated in one cohort and two case-control studies. The cohort study as well as one of the two case-control studies reported a significant association between periodontitis and PLBW (odds ratios 4.4-7.9). From two additional case-control studies microbiological data could be extracted. Bacteroides forsythus was found to be associated with PLBW in both studies. In conclusion, the evidence linking periodontitis with an increased risk for CHD and PLBW is limited. There is a clear need for new, well designed observational and intervention studies to confirm the thus far observed associations, explore the validity of the associations in diverse populations, establish whether they are causal in nature and determine potential benefits of periodontal intervention in reducing the risk for these conditions.

Oral infections and systemic diseases

An association between periodontal infection and CVD has been revealed in some epidemiologic studies, whereas other studies were unable to demonstrate such an association. A link between the two diseases may be explained by shared established or nonestablished risk factors. Future studies with extended control of confounding factors and intervention studies may add to the understanding of a possible relationship between the diseases. In some cases, IE is caused by dental plaque bacteria. Several studies are suggestive of oral bacteria causing respiratory infection. The pathogenesis and course of a number of other diseases including DM and rheumatoid arthritis have been associated wish periodontitis, but more research is necessary to elucidate possible pathogenic interactions.

Periodontal disease is associated with brachial artery endothelial dysfunction and systemic inflammation

OBJECTIVE

The purpose of this study was to determine whether periodontal disease is associated with endothelial dysfunction and systemic inflammation. Epidemiological studies suggest that severe periodontal disease is associated with increased cardiovascular disease risk, but the mechanisms remain unknown.

METHODS AND RESULTS

We assessed flow-mediated dilation and nitroglycerin-mediated dilation of the brachial artery using vascular ultrasound in 26 subjects with advanced periodontal disease and 29 control subjects. The groups were matched for age and sex, and patients with hypercholesterolemia, diabetes mellitus, hypertension, and history of cigarette smoking were excluded. We also examined serum levels of C-reactive protein using an established high-sensitivity method. Subjects with advanced periodontal disease had lower flow-mediated dilation compared with control patients (7.8+/-4.6% versus 11.7+/-5.3%, P=0.005). Nitroglycerin-mediated dilation was equivalent in the two groups. Subjects with advanced periodontitis exhibited higher serum levels of high-sensitivity C-reactive protein compared with healthy controls patients (2.3+/-2.3 versus 1.0+/-1.0 mg/L, P=0.03).

CONCLUSIONS

Subjects with advanced periodontal disease exhibit endothelial dysfunction and evidence of systemic inflammation, possibly placing them at increased risk for cardiovascular disease.

Relationship of destructive periodontal disease to the acute-phase response

BACKGROUND

Destructive periodontal diseases have been associated with an increased risk of atherosclerotic complications; however, the potential mechanisms are yet to be defined. Inflammation plays a central role in atherosclerosis since C-reactive protein (CRP), an acute-phase protein monitored as a marker of inflammatory status, has been identified as a major risk factor for atherosclerotic complications. Recent reports that destructive periodontal diseases can increase CRP values present the possibility that the acute-phase response may link these 2 disease processes. The objective of the present investigation was to determine the effect of destructive periodontal disease status, severity, and progression on components of the acute-phase response in an urban minority population.

METHODS

Clinical measurements recorded included probing depth, attachment level, gingival erythema, bleeding upon probing, suppuration, and plaque. Disease progression was defined as a >2 mm loss of attachment 2 months post-baseline. Serum antibody was measured by enzyme-linked immunosorbent assay. CRP was measured using a high-sensitivity CRP (hsCRP) assay. A commercial laboratory measured serum glucose (non-fasting), albumin, cholesterol, high-density lipoprotein (HDL), triglycerides, low-density lipoprotein (LDL), and iron.

RESULTS

Increased serum IgG antibody to Porphyromonas gingivalis, but not to 5 other species, was associated with periodontal disease status, increased severity, and progression as were age, male gender, and smoking. Cholesterol and LDL were increased in disease, and HDL and iron were increased in health. hsCRP, glucose, and cholesterol increased with disease progression. By regression analysis, IgG antibody to P. gingivalis correlated with age, probing depth, and hsCRP, and negatively correlated with albumin and iron. By logistic regression, subjects who experienced multiple sites of disease progression and elevated antibody to P. gingivalis increased the odds ratio of hsCRP>2.08 mg/l by 14.1 and 5.6, respectively.

CONCLUSION

These results suggest that destructive periodontal disease and disease progression are associated with changes in serum components consistent with an acute-phase response.

The role of infection in the pathogenesis of cardiovascular disease

Atherosclerosis is a complex, multifactorial disease. Recently, research has intensified to identify the role of various infections in the pathogenesis of atherosclerosis. Specific agents have been proposed as direct initiators or accelerators of atherosclerosis, while other infectious agents have been proposed as accelerators of atherosclerosis through nonspecific stimulation of the inflammatory cascade. Recently, the total pathogen burden concept has suggested that while each specific infection contributes only slightly to the pathogenesis of atherosclerosis, the cumulative effects of infectious agents contribute greatly. Several randomized trials evaluating antibiotic therapy in the prevention of cardiovascular events have now been completed, although results have been conflicting. This manuscript summarizes current understanding of the role of infectious agents as a trigger of inflammation, as a contributor to atherosclerosis, and the potential role of antibiotic therapy in the treatment of atherosclerosis.

Meta-analysis of periodontal disease and risk of coronary heart disease and stroke

OBJECTIVE

The purpose of this study was to analyze published studies and abstracts in order to provide a quantitative summary of periodontal disease as a risk factor for cardiovascular disease and to explore the possible causes for conflicting results in the literature.

STUDY DESIGN

We searched all published literature on the Medline literature search engine since 1980. An additional search was performed with bibliographic citations from each article. Nine cohort studies (8 prospective and 1 retrospective), in which relative risks (RRs), CIs, and P values were reported or could be calculated were included. Four researchers independently extracted RRs, CIs, and P values from each study and evaluated the degree of confounding adjustment. The combined result was calculated with weighted average, and sources of disparity were tested with regression analyses.

RESULTS

The summary RR was 1.19 (95% CI, 1.08 1.32), indicating a higher risk of future cardiovascular events in individuals with periodontal disease compared with those without. In an analysis stratified to individuals of </=65 years of age, the RR was 1.44 (95% CI, 1.20 to 1.73). When the outcome was restricted to stroke only, the RR was 2.85 (95% CI, 1.78 to 4.56). In the metaregression analysis, the effects of residual confounding caused an overestimate of the results by 12.9% and, with a proxy for periodontal disease, caused an underestimate of 29.7%.

CONCLUSIONS

Periodontal disease appears to be associated with a 19% increase in risk of future cardiovascular disease. This increase in RR is more prominent (44%) in persons aged </=65 years. Although the increment of risk between subjects with or without periodontal disease in the general population is modest, at around 20% because nearly 40% of population has periodontal disease, this modest increase may have a profound public health impact.

Effect of treatment of chronic periodontitis on levels of serum markers of acute-phase inflammatory and vascular responses

AIMS

Recent epidemiological work suggests an association between periodontal disease severity and cardiovascular disease risk. This study aimed to ascertain if circulating levels of cardiovascular and systemic inflammatory markers could be modified following treatment of periodontal disease.

METHOD

Adult subjects were recruited from those awaiting periodontal treatment and randomised to either immediate (test, n=24) or delayed treatment (control, n=15). Demographic and clinical data were collected and venous blood was taken before and either 6 weeks after completion of treatment or after an equivalent 3-month control period. Periodontal examination included probing depth, loss of attachment, plaque scores and bleeding scores. Blood was analysed to determine serum and plasma fibrinogen, C-reactive protein, sialic acid, tumour necrosis factor-alpha and interleukin -6 and -1beta. Effects of treatment were assessed by paired tests and analysis of variance by treatment group with baseline covariates.

RESULTS

Treatment improved plaque and bleeding scores and reduced probing depths (p<0.002). However, there were no statistically significant changes in levels of any of the systemic markers.

CONCLUSION

Improvement in periodontal health did not influence the levels of vascular markers.

WBC count, atherosclerosis and coronary risk factors

An association between total white blood cell (WBC) count and the risk of coronary heart disease (CHD) is well known. In the present study, we investigated the relationship between WBC counts and other clinical factors including coronary risk factors, and periodontal disease in 1,620 adults. Factors found to have a significant association with the WBC count by multivariate regression analysis were age (negative association), body mass index (negative association), serum triglycerides, high-density lipoprotein cholesterol (negative association), and periodontal levels in the smoking group.Whereas, in the non-smoking group, systolic blood pressure and diastolic blood pressure (negative association) were included and serum triglycerides were excluded.Non-smoking subjects who were free of periodontal disease had a mean WBC count of 4.69 +/- 1.0 x 109 cells/l. This value can be used as a reference for WBC counts in healthy subjects. Our data suggest that values significantly higher than this could be an important indicator of inflammation derived from cigarette smoking or periodontal disease. Further study is necessary to determine whether an improvement in the WBC count could prevent the occurrence of CHD.

Association between periodontal disease and left ventricle mass in essential hypertension

Chronic periodontitis has been associated with an increased risk for cardiovascular disease. Left ventricular mass is an established independent predictor of cardiovascular disease. In the present cross-sectional study, we tested the association between periodontitis and left ventricular mass in subjects with essential hypertension. One hundred four untreated subjects with essential hypertension underwent clinical examinations, including echocardiographic study, laboratory tests, and assessment of periodontal status according to the community periodontal index of treatment needs (CPITN). With increasing severity of periodontitis, there was a progressive increase in left ventricle mass. Mean values (g/height2.7) were 39.0 (+/-2.7) in CPITN 0 (periodontal health), 40.2 (+/-6.4) in CPITN 1 (gingival bleeding), 42.7 (+/-6.8) in CPITN 2 (calculus), 51.4 (+/-11.7) in CPITN 3 (pockets 4 to 5 mm), and 76.7 (+/-11.3) in CPITN 4 (pockets > or =6 mm) (overall F 51.2; P<0.0001). Body surface area (P=0.04), systolic (P<0.0001) and diastolic (P<0.01) blood pressure, and left ventricular mass (P<0.0001) were determinants of a composite of CPITN 3 and 4. In a multivariate logistic analysis, left ventricular mass was the sole determinant (P<0.0001) of CPITN stages 3 and 4. Our findings suggest a direct association between severity of periodontitis and left ventricular mass in subjects with essential hypertension. Periodontal evaluation might contribute to refine cardiovascular risk assessment in hypertensive subjects.

Oral health and health behavior in patients referred for open-heart surgery

OBJECTIVE

Little is known about the dental health and health behavior of patients referred for open-heart surgery because of severe heart disease. Yet, coronary atherosclerosis has been suggested to be an inflammatory disease in which chronic dental infections may trigger pathogenic mechanisms in the walls of arteries. In epidemiological studies periodontal disease in particular has been linked with coronary heart disease (CHD).

STUDY DESIGN

We set out to investigate by means of clinical examination, x-ray, and questionnaire the oral health status, health-related behavior, and conceptions of 256 CHD patients referred for open-heart surgery in the Kuopio University Hospital. The patients' heart disease was New York Heart Association grades II-IV. For comparison, 250 age- and sex-matched non-CHD patients were also studied. Differences between groups were analyzed conventionally and with the Total Dental Index (TDI), which uses linear modeling and logistic regression analyses to summarize periodontal factors and other signs of oral infections. We expected to find neglected dental care and worse oral health situation among the CHD patients.

RESULTS

Edentulousness was seen in 35% of the CHD group and in 15% of the non-CHD group (P < .001). The CHD group had significantly lower number of teeth (8.8 +/- 9.1) than the non-CHD group (17 +/- 10.5; P < .001). No dental appointment in the past 10 years was reported in 66% of the CHD patients and 35% of the non-CHD patients. Forty-nine percent of the CHD group and 69% of the non-CHD group had had a dental visit within the past 2 years (P < .001). Daily tooth brushing was reported by 46% of the CHD group and 56% of the non-CHD group (P < .05). Only 2% of the CHD group and 8% of the non-CHD group flossed daily (P < .001). TDI scores were significantly higher in the edentulous than in the dentate study groups (P < .001), but no difference was observed between CHD and non-CHD patients of the same dentate or edentulous status. Mean TDI score was 3.2 +/- 0.8 in edentulous CHD patients and 3.1 +/- 0.4 in edentulous non-CHD patients; the scores in the dentate patients were 2.5 +/- 0.9 in the CHD group and 2.4 +/- 2.0 in the non-CHD group. The TDI score appeared almost significant a predictor of CHD when used as a dependent variable in logistic regression analysis (P = .08).

CONCLUSION

Worse oral health status and less satisfactory oral health behavior were observed in the CHD patients than among the cardiologically healthy.

Periodontal disease, tooth loss, and incidence of ischemic stroke

BACKGROUND AND PURPOSE

Periodontal and other infections have been suggested as potential risk factors for stroke. This study evaluates periodontal disease and tooth loss as risk factors for ischemic stroke.

METHODS

The study population consisted of 41 380 men who were free of cardiovascular disease and diabetes at baseline. Periodontal disease history was assessed by mailed validated questionnaires. During 12 years of follow-up, stroke incidence was assessed and subclassified by use of medical history, medical records, and imaging reports. Hazard ratios (HRs) were adjusted for age, amount smoked, obesity, alcohol, exercise, family history of cardiovascular disease, multivitamin use, vitamin E use, profession, baseline reported hypertension, and hypercholesterolemia. Sex and socioeconomic status were inherently controlled for by restriction. Confounding variables were updated in the analyses for each 2-year follow-up interval.

RESULTS

We documented 349 ischemic stroke cases during the follow-up period. Men who had < or =24 teeth at baseline were at a higher risk of stroke compared to men with > or =25 teeth (HR=1.57; 95% CI, 1.24 to 1.98). There was little evidence of an increased risk with recent tooth loss during follow-up. A modest association was seen between baseline periodontal disease history and ischemic stroke (HR=1.33; 95% CI, 1.03 to 1.70). Addition of dietary factors to the model changed the HR only slightly.

CONCLUSIONS

Our results suggest that periodontal disease and fewer teeth may be associated with increased risk of ischemic stroke.

Relationships Among Clinical Measures of Periodontal Disease and Their Associations With Systemic Markers

BACKGROUND

Recent investigations of the relationship between periodontitis and systemic disease require that periodontal disease also must be thought of as a disease process that is an exposure for a systemic disease or condition (outcome), rather than as the outcome itself. When viewing periodontal disease as an exposure, investigators must consider the clinical, microbiological, and inflammatory components of periodontitis that potentially convey risk for the systemic outcome of interest, which may or may not be the same as those associated with the assessments used to define tooth-based disease. Another important consideration is the temporal relationship between the exposure and the outcome of interest.

METHODS

To explore which definitions of periodontal disease or clustering of clinical signs are important with regards to systemic exposure to inflammatory stress, we examined the relationship between clinical periodontal disease measures and 2 systemic inflammatory markers of increased risk for cardiovascular disease: serum soluble intercellular adhesion molecule (sICAM), which is a measure of vascular stress and serum C-reactive protein (CRP), which is a measure of hepatic acute-phase response. The Dental Arteriosclerosis Risk in Communities (ARIC) study, a cross-sectional study of the relationship between periodontal disease and cardiovascular disease, forms the basis for the examples used in this investigation.

RESULTS

Our findings demonstrated that while attachment loss, probing depth, (PD) and bleeding on probing (BOP) are individually associated with sICAM and CRP, only BOP remains significant for sICAM when all 3 are in the model and, for CRP, only PD remains significant. Both of these clinical parameters were more robust in estimating the degree of systemic inflammation than traditional classifications of mild, moderate, and severe periodontitis or other measures of disease severity such as attachment loss.

CONCLUSIONS

When selecting a definition of "systemic periodontitis" (periodontal disease that represents an exposure for a systemic condition), it is helpful to think of periodontal disease as a chronic oral infection with a number of clinical signs, rather than as the dento-centrically defined entity, periodontal disease. Thus, "systemic periodontitis" should be defined predicated upon those clinical signs that best represent the underlying mechanisms and temporal sequence that may affect that systemic outcome.

Inflammation and infection in clinical stroke

Stroke has enormous clinical, social, and economic implications, and demands a significant effort from both basic and clinical science in the search for successful therapies. Atherosclerosis, the pathologic process underlying most coronary artery disease and the majority of ischemic stroke in humans, is an inflammatory process. Complex interactions occur between the classic risk factors for atherosclerosis and its clinical consequences. These interactions appear to involve inflammatory mechanisms both in the periphery and in the CNS. Central nervous system inflammation is important in the pathophysiologic processes occurring after the onset of cerebral ischemia in ischemic stroke, subarachnoid hemorrhage, and head injury. In addition, inflammation in the CNS or in the periphery may be a risk factor for the initial development of cerebral ischemia. Peripheral infection and inflammatory processes are likely to be important in this respect. Thus, it appears that inflammation may be important both before, in predisposing to a stroke, and afterwards, where it is important in the mechanisms of cerebral injury and repair. Inflammation is mediated by both molecular components, including cytokines, and cellular components, such as leukocytes and microglia, many of which possess pro- and/or antiinflammatory properties, with harmful or beneficial effects. Classic acute-phase reactants and body temperature are also modified in stroke, and may be useful in the prediction of events, outcome, and as therapeutic targets. New imaging techniques are important clinically because they facilitate dynamic evaluation of tissue damage in relation to outcome. Inflammatory conditions such as giant cell arteritis and systemic lupus erythematosus predispose to stroke, as do a range of acute and chronic infections, principally respiratory. Diverse mechanisms have been proposed to account for inflammation and infection-associated stroke, ranging from classic risk factors to disturbances of the immune and coagulation systems. Considerable opportunities therefore exist for the development of novel therapies. It seems likely that drugs currently used in the treatment of stroke, such as aspirin, statins, and modulators of the renin-angiotensin-aldosterone system, act at least partly via antiinflammatory mechanisms. Newer approaches have included antimicrobial and antileukocyte strategies. One of the most promising avenues may be the use of cytokine antagonism, for example, interleukin-1 receptor antagonist.

Cellular Responses to Oral Pathogens

BACKGROUND

Several previous epidemiological studies, along with the results of more recent animal model approaches, have suggested a role for periodontitis in atherosclerosis. Such an association could be mediated by direct interactions of periodontopathic bacteria with host vascular tissues.

METHODS

The interactions of Porphyromonas gingivalis with endothelial cells and macrophages in vitro were investigated relative to modification of low-density lipoproteins (LDL).

RESULTS

P. gingivalis 381, its outer membrane vesicles, and the lipopolysaccharide (LPS) derived from these organisms were all shown to induce modification of LDL in the presence of the murine macrophage J774.A.1. Such alterations led to an increase in the migration of the particles through agarose gels. In addition, direct modification of LDL by strain 381 was demonstrated in the absence of macrophages. This latter property appears to be related to the potent protease activities of the bacterium. These properties may contribute to modification of LDL to forms which have been strongly implicated in cholesterol lipid accumulation in vascular tissues. P. gingivalis 381 also appears to induce cyclooxygenase-2 expression in endothelial cells as determined with human umbilical vascular endothelial cells (HUVEC).

CONCLUSIONS

These in vitro results with vascular cells in culture suggest a molecular basis for a potential role for periodontopathic bacteria such as P. gingivalis in augmenting foam cell formation characteristic of atherosclerotic lesions.

Novel risk factors for peripheral arterial disease in young women

PURPOSE

To investigate traditional and novel risk factors (homocysteine and C-reactive protein levels, and exposure to infections) for peripheral arterial disease in young women.

SUBJECTS AND METHODS

In a multicenter, population-based, case-control study, 212 young women (mean [+/- SD] age, 48.2 +/- 7.0 years) with peripheral arterial disease and 475 healthy control women (mean age, 45.5 +/- 8.1 years) completed a standardized questionnaire and provided blood samples. Peripheral arterial disease was angiographically confirmed if a stenotic lesion (more than 50% reduction of the lumen) was present in at least one major peripheral artery. Hyperhomocysteinemia was defined as a nonfasting plasma homocysteine level exceeding the 90th percentile of the control group. History of infectious diseases was determined by questionnaire.

RESULTS

Elevated C-reactive protein levels were associated with an increased likelihood of peripheral arterial disease (odds ratio [OR] = 3.9; 95% confidence interval [CI]: 1.8 to 8.5 for women in the third quartile; OR = 3.1; 95% CI: 1.4 to 6.8 for women in the fourth quartile; both comparisons with women in the first quartile). Hyperhomocysteinemia was not associated with a significantly increased risk of peripheral arterial disease (OR = 1.6; 95% CI: 0.9 to 3.0). A history of chickenpox, shingles, mumps, pneumonia, chronic bronchitis, peptic ulcer, or periodontitis was independently related to peripheral arterial disease, with adjusted odds ratios varying from 1.7 (95% CI: 1.0 to 3.1) for mumps to 3.4 (95% CI: 1.5 to 7.7) for peptic ulcer. The risk of peripheral arterial disease increased with the number of these infections; exposure to five or more infections increased the odds 3.7-fold (95% CI: 1.7 to 8.2). This association was not affected by the level of C-reactive protein.

CONCLUSION

Our results do not support a strong relation between homocysteine and peripheral arterial disease in young women. However, an elevated C-reactive protein level and several types of symptomatic infection were associated with peripheral arterial disease.

Investigation of the association between angiographically defined coronary artery disease and periodontal disease

BACKGROUND

The association between periodontal disease and coronary artery disease (CAD) has been investigated in numerous studies with inconsistent results. Resolving these differences is complicated by the use of varying definitions of CAD. The aim of this study was to investigate the association between angiographically-defined CAD and periodontal disease.

METHODS

Non-smoking, non-diabetic patients, over 40 years of age, with no history of a myocardial infarction in the previous 6 months and who had undergone cardiac catheterization within the previous 12 months were enrolled in this study. Subjects were classified as having CAD (CAD+) if they had 50% stenosis in at least one major epicardial artery and classified as CAD negative (CAD-) if they had <50% stenosis in all identified arteries. Periodontal disease severity was measured through bleeding on probing, probing depth, clinical attachment level (CAL), gingival recession, number of missing teeth, and radiographic bone loss.

RESULTS

One hundred (53 = CAD+; 47 = CAD-) patients were examined. CAD+ patients were more likely to be male (CAD+ 83.0% male; CAD- 40.4% male; P= 0.001), and were older (CAD+ 65.3 years; CAD- 60.8 years; P= 0.0138). Although all patients reported they were currently non-smokers and had not smoked for at least 5 years, the fraction who were former smokers was greater for CAD+ patients (66% versus 24.4%; P = 0.0001) and mean pack/year history of smoking was higher for CAD+ patients (15.8 versus 4.5; P = 0.0003). Mean CAL (3.13 mm versus 2.78 mm; P 0.0227), number of sites with CAL > or = 6 mm (6.85 versus 3.32; P = 0.0242), radiographic bone loss (3.60 mm versus 3.18 mm; P = 0.0142) were greater for CAD+ patients than for CAD- patients. However, after adjustment for age and previous smoking history, factors common to both diseases, the associations of CAD and periodontal disease were reduced and were not statistically significant (odds ratio [OR]: mean CAL OR = 1.06; number of sites with CAL > or = 6 mm OR = 1.03; mean radiographic bone loss OR = 1.31; P > or = 0.2055).

CONCLUSIONS

After accounting for factors common to both periodontal disease and CAD, there was no significant association between periodontal disease and chronic CAD as assessed angiographically. Further investigations into the relationship between periodontal disease and CAD should clearly separate chronic CAD and acute coronary events.

The role of inflammation and infection in the pathogenesis and evolution of coronary artery disease

Inflammation plays a major role in the initiation and progression of coronary artery disease (CAD) and the precipitation of acute coronary events. However, the inflammatory triggers are poorly understood. Noninfectious stimuli undoubtedly play a role. Recently, chronic infection has been proposed as another inflammatory trigger. Histologically, unstable atherosclerotic plaque contains activated macrophages and T lymphocytes, adhesion molecules, chemokines and cytokines, matrix-degrading enzymes, and prothrombotic factors. Circulating inflammatory markers such as C-reactive protein, fibrinogen, and interleukins are increased in high-risk cohorts and predict future risk. Experimental models and human studies have supported a role of infection in the promotion of atherosclerosis. Although the independent predictive value of seropositivity to individual agents has varied, total pathogen burden, the sum of seropositivities to many bacterial and viral vectors, has been more consistent. Whether antibiotics or vaccines will be useful in CAD prevention remains to be shown. Meanwhile, therapies with proven vascular anti-inflammatory effects (eg, diet, exercise, smoking cessation, aspirin, statins) should be optimized.

Dentistry and distributive justice

There is a growing concern in most countries to address the problem of inequities in health-care within the context of financial restraints on the public purse and the realities of health professions that are influenced strongly by the economic priorities of free-market economies. Dental professionals, like other health professionals, are well aware that the public expects oral health-related services that are effective, accessible, available and affordable. Yet, there is remarkably little reference in the literature to the theories of distributive justice that might offer guidance on how an equitable oral health service could be achieved. This paper considers three prominent theories of distributive justice--libertarianism, egalitarianism and contractarianism--within the controversial context of basic care and quality of life. The discussion leads towards a socially responsible, egalitarian perspective on prevention augmented by a social contract for curative care with the aim of providing maximum benefit to the least advantaged in society.

Higher C-reactive protein concentration and white blood cell count in subjects with more coronary risk factors and/or lower physical fitness among apparently healthy Japanese

Of 2,722 people (1.876 men, mean age: 51.3+/-10.3 years; 846 women, mean age: 51.4+/-11.1) who underwent the fitness check program at Aichi Prefectural Center for Health Care, the concentration of C-reactive protein (CRP) and the white blood cell count (WBC) were investigated in relation to the number of coronary risk factors, maximum oxygen uptake (VO2max) quartiles and physical fitness score. CRP was measured by conventional latex immunoturbidimetric assay. Both CRP and WBC were higher in those who had more risk factors. In men the lowest mean CRP was 0.07 mg/dl in those with only one risk factor (RF1) and the highest was 0.29 mg/dl in RF6 (p<0.0001). The lowest mean WBC was 4,868/mm3 in RF1 and the highest was 7,096/mm3 in RF6 (p<0.0001). In women the lowest mean CRP was 0.073 mg/dl in those with no risk factors (RF0) and the highest was 0.22mg/dl in RF5 (p=0.0379). The lowest mean WBC was 5,065/mm3 in RF1, and the highest was 6,792/mm3 in RF4 (p=0.0001). A similar relationship was noticed when the groups were analyzed by VO2max quartile or fitness score. CRP and WBC both showed a stepwise increase or decrease in men, but was generally in order in women in accordance with the number of risk factors, VO2max level or fitness score. In apparently healthy Japanese subjects, elevated inflammatory indices (ie, higher CRP and WBC) were associated with more coronary risk factors and poorer physical fitness. Therefore, high-risk coronary subjects might be screened by conventional measurement of CRP.

Does chronic periodontitis cause coronary heart disease? A review of the literature

BACKGROUND

Chronic periodontitis, or CP, has been associated with coronary heart disease, or CHD. This article reviews the available prospective CP-CHD evidence.

LITERATURE REVIEWED

In nine cohort studies, CP was associated with a 15 percent greater risk of developing CHD. Conclusions from individual studies depended on study characteristics. Summary risk estimates for studies controlling for smoking intensity (five of nine studies) or health awareness (two of nine studies) or studies with more than 600 CHD events (three of nine studies) suggest that CP is either not at all or weakly associated with CHD. Summary risk estimates for the studies that did not control for these factors or that examined an insufficient number of CHD events reported a weak increase in CHD risk associated with CP (20 percent greater). These data suggest that the CP-CHD associations observed in smaller studies are due to insufficient control for lifestyle differences. In addition, one cohort study reported that edentulous people had a CHD risk similar to that of people with CP. Therefore, the plausibility of dental infection elimination affecting CHD risk appears limited.

SUMMARY

Current evidence supporting a causal CP-CHD link is weak. Rigorous methodological and analytical control of lifestyle factors such as smoking will be required to elucidate whether the CP-CHD disease association is either small or nonexistent.

CLINICAL IMPLICATIONS

Cigarette smoking destroys both oral and systemic health. Because of this strong common causal factor, oral and systemic health are linked. Dentistry should continue to play an important role in implementing smoking prevention and cessation programs.

Periodontal disease and cardiovascular disease: epidemiology and possible mechanisms

BACKGROUND

Many early epidemiologic studies reported an association between periodontal disease and cardiovascular disease. However, other studies found no association or nonsignificant trends. This report summarizes the evidence from epidemiologic studies and studies that focused on potential contributing mechanisms to provide a more complete picture of the association between periodontal and heart disease.

TYPES OF STUDIES REVIEWED

The authors summarize the longitudinal studies reported to date, because they represent the highest level of evidence available regarding the connection between periodontal disease and heart disease. The authors also review many of the case-control and cross-sectional studies published, as well as findings from clinical, animal and basic laboratory studies.

RESULTS

The evidence suggests a moderate association--but not a causal relationship--between periodontal disease and heart disease. Results of some case-control studies indicate that subgingival periodontal pathogenic infection may be associated with myocardial infarction. Basic laboratory studies point to the biological plausibility of this association, since oral bacteria have been found in carotid atheromas and some oral bacteria may be associated with platelet aggregation, an event important for thrombosis. Animal studies have shown that atheroma formation can be enhanced by exposure to periodontal pathogens.

CONCLUSIONS

The accumulation of epidemiologic, in vitro, clinical and animal evidence suggests that periodontal infection may be a contributing risk factor for heart disease. However, legitimate concerns have arisen about the nature of this relationship. These are early investigations. Since even a moderate risk contributed by periodontal disease to heart disease could contribute to significant morbidity and mortality, it is imperative that further studies be conducted to evaluate this relationship. One particularly important study to be carried out is the investigation of a possible clinically meaningful reduction in heart disease resulting from the prevention or treatment of periodontal disease.

The relationship between oral conditions and ischemic stroke and peripheral vascular disease

BACKGROUND

This article is a critical review of the epidemiologic studies linking or disassociating oral conditions with stroke and peripheral vascular disease, or PVD. It also describes possible causal and non-causal pathways for these associations.

TYPES OF STUDIES REVIEWED

The author reviewed studies that evaluated the oral conditions of periodontal disease or tooth loss as risk factors for arterial disease and stroke.

RESULTS

Seven of nine studies evaluating tooth loss and periodontal disease as risk factors for stroke or PVD showed some significant associations. The studies varied in the exposures and outcomes evaluated; therefore, the associations were not consistently replicated. It is unclear whether the associations found between these oral conditions and cardiovascular disease had any causal component. In the absence of any causal relationship, the associations may be explained by common risk factors. Alternatively, there may be a causal relationship that may be explained by one or more potential causal pathways. Further epidemiologic studies are needed, and the role of nutrition and other inflammatory mediators needs to be explored further in this context.

CLINICAL IMPLICATIONS

It is recommended that clinicians continue to provide standard professional care, as well as nutritional counseling to help patients maintain a healthy diet after extractions. Clinicians are cautioned against suggesting extractions as a means of preventing cardiovascular disease.

Association between periodontal pockets and elevated cholesterol and low density lipoprotein cholesterol levels

BACKGROUND

Periodontitis is associated with increased prevalence of cardiovascular morbidity and mortality; however, the nature of this association is unclear. There is a rationale that indicates that the presence of periodontal pockets which can harbor pathogenic microorganisms and evoke a host response could elicit a systemic effect. The hypothesis of this study is that periodontal pockets may be associated with elevated blood lipid levels, a known risk factor for atherosclerotic disease.

METHODS

The periodontal health of 10,590 Israeli military service men and women was assessed using the Community Periodontal Index of Treatment Needs (CPITN). The relationship of blood lipids and periodontal disease and CPITN index was tested, controlling for factors that are related to elevated cholesterol levels, including high body mass index (BMI), age, diastolic blood pressure, and smoking.

RESULTS

The presence of periodontal pockets was positively associated with higher cholesterol and low density lipoprotein (LDL) cholesterol blood levels in men. No significant association was found in women.

CONCLUSIONS

In this large cohort study, the presence of periodontal pockets as measured by CPITN was positively associated with total cholesterol and LDL-cholesterol. The findings of the study support the reports linking increased prevalence of cardiovascular mortality among patients with periodontal disease.

Porphyromonas gingivalis infection accelerates the progression of atherosclerosis in a heterozygous apolipoprotein E-deficient murine model

BACKGROUND

Current epidemiological data suggest that dental infections affecting tooth-supporting tissues (periodontitis) can disseminate into the systemic circulation and thereby contribute to atherosclerosis progression. To test this hypothesis, we investigated the effect of repeated systemic inoculations with Porphyromonas gingivalis (Pg), a putative periodontal pathogen, on the progression of atherosclerosis in heterozygous apolipoprotein E-deficient (ApoE(+/-)) mice.

METHODS AND RESULTS

Ten-week-old, male ApoE(+/-) mice fed either a high-fat diet or regular chow were inoculated intravenously with live Pg (10(7) CFU) or vehicle once per week for 10, 14, or 24 consecutive weeks. Histomorphometry of plaque cross-sectional area in the proximal aortas, en face measurement of plaque area over the aortic trees, Pg 16S ribosomal DNA amplification with polymerase chain reaction, ELISA for systemic proinflammatory mediators, and immunolocalization of macrophages in the proximal aorta were performed. Atherosclerotic lesions of the proximal aortas and aortic trees were more advanced in Pg-challenged animals than in vehicle control animals and occurred earlier (at 10 weeks) when no lesions were apparent in control animals. At 24 weeks after inoculation, proximal aortic lesion size quantified by histomorphometry was 9-fold greater in chow-fed mice inoculated with Pg than in noninoculated mice (P<0.001) and was 2-fold greater in Pg-inoculated versus noninoculated high-fat diet-fed mice (P<0.001); all atherosclerotic lesions were macrophage-rich. Pg ribosomal DNA was found in the aortas, livers, and hearts 24 weeks after inoculation.

CONCLUSIONS

These results provide evidence that long-term systemic challenge with Porphyromonas gingivalis, an oral pathogen, can accelerate atherogenic plaque progression.

The association between periodontal diseases and cardiovascular diseases: a state-of-the-science review

Early case-control and cross-sectional studies demonstrating associations between chronic periodontitis and cardiovascular disease (CVD) were quickly followed by secondary analyses of data available from existing longitudinal studies, which indicated that individuals with periodontitis, as determined by clinical measures, were at greater risk for CVD events. Many of these studies contained large numbers of subjects and were adjusted for traditional risk factors. Within the last 18 months, one case-control study and one longitudinal study have reported finding positive associations that were not statistically significant. The earlier studies stimulated a number of studies focused on identifying potential biological mechanisms that might underlie this association. While still early in that process, such studies have implicated a systemic role for oral microorganisms and for the quality and quantity of the host inflammatory response as key biologic processes that may underlie the association of CVD with the clinical manifestation of periodontitis. It is a positive development when changes in our knowledge regarding biologic mechanisms result in reevaluation of past studies, and this reevaluation leads to new studies that incorporate the design elements demanded by this new knowledge. In that spirit, we conclude that all longitudinal studies reported to date can be characterized as follows: none were initially designed to actually test the association of interest; almost all were restricted to clinical measures of periodontitis to index the exposure and lacked measures of infectious burden and host response; and they used a variety of cardiovascular clinical events to index the outcome and did not include subclinical measures of atherosclerosis. In addition, the longitudinal studies that failed to show a significant association between periodontitis and CVD used the least sensitive and crudest clinical measures of periodontal disease. Based upon the current state-of-the-science, all previous studies should be viewed as lacking sufficiently sensitive and comprehensive measures of periodontal disease as a systemic exposure. Since the potential health care impact of this relationship might be extensive, it is time to enter the next phase of research by conducting molecular epidemiology studies that are appropriately designed to test our current understanding of the molecular and cellular mechanisms involved.

General health risk of periodontal disease

The possibility that periodontal disease might influence the morbidity and mortality of systemic diseases constitutes a research topic of great current interest. Human periodontal disease is associated with a complex microbiota containing approximately 500 microbial taxa and various human viruses, many of which possess significant virulence potential. Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and other periodontopathic bacteria that are unique to the oral cavity and may disseminate to other body sites comprise the best-documented form of dental focal infection. However, systemically healthy individuals seem to be at low risk of acquiring acute non-oral diseases from direct infections by periodontal pathogens. Research data from various laboratories point to periodontal infections as a risk factor for chronic medical disorders, including cardiovascular disease, cerebrovascular accidents and low-birth-weight infants. However, recent epidemiological studies have failed to show a significant relationship between periodontal disease and cardiovascular disease. This review paper evaluates the current status of knowledge on dental focal infection and suggests avenues for further research into the topic of general health risks of periodontal disease.