Age, dental infections, and coronary heart disease

The Role of Cigarette Smoking in the Association Between Periodontal Disease and Coronary Heart Disease

BACKGROUND

Cigarette smoking is a significant risk factor for both coronary heart disease and periodontal disease. The goal of this study was to better understand the role of smoking in the relationship between periodontal disease and heart attack history.

METHODS

The study population consisted of 5,285 participants in the Third National Health and Nutrition Examination Survey (NHANES) during 1988-1994 and who were age 40 years or older when examined. The data analysis employed logistic regression models and accounted for the complex sampling design used in NHANES.

RESULTS

After adjustment for potential confounders, we only found significant associations between periodontal loss of attachment (LOA) and heart attack history for smokers, with odds ratios and 95% confidence interval (CI) of 2.64 (1.48 to 4.71), 3.84 (1.22 to 12.10) and 5.87 (1.91 to 18.00) for those with 2.0 to 2.99, 3.0 to 3.99, and 4 mm or more mean LOA, respectively. When the analysis was stratified by smoking status and tertile of age at heart attack, the statistically significant associations were limited to smokers who had a heart attack between the ages of 25 and 50 years, with odds ratios and 95% Cl associated with increasing mean LOA for this group of 3.29 (1.35 to 8.04), 7.32 (1.60 to 33.51), and 8.04 (1.91 to 18.00), respectively.

CONCLUSIONS

These results suggest that cigarette smoking is a necessary cofactor in the relationship between periodontal disease and coronary heart disease, and the increase in risk appears to be age dependent. However, the key role played by smoking in the etiology of both periodontal and heart diseases makes it difficult to determine how much of the observed association resulted from periodontal disease.

Periodontal management of patients with cardiovascular diseases

Periodontists are often called upon to provide periodontal therapy for patients with a variety of cardiovascular diseases. Safe and effective periodontal treatment requires a general understanding of the underlying cardiovascular diseases, their medical management, and necessary modifications to dental/periodontal therapy that may be required. In this informational paper more common cardiovascular disorders will be discussed and dental management considerations briefly described. This paper is intended for the use of periodontists and members of the dental profession.

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.

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.

Oral health in the elderly with non-insulin-dependent diabetes mellitus

Non-insulin-dependent diabetes mellitus (NIDDM) is a common endocrine disease affecting the elderly in particular. Long-term complications involve the vasculature; vision, renal, and neural function; and the periodontium. Knowledge about the oral health of the elderly and the effects of NIDDM is limited. The objective of this study was to compare the oral health of patients aged 60+ years, who have NIDDM, with patients who do not have NIDDM. To evaluate oral health, we recorded retention and condition of the teeth, periodontal health, and condition of the oral mucosa. We also assessed oral hygiene, smoking history, regularity of dental checkups, and medication use. The study group was selected from among patients who came to the ambulatory care clinic at University of Medicine and Dentistry, New Jersey, Center for Aging with a diagnosis of NIDDM. The control group, which did not have NIDDM, was selected from among the same patient group and was matched for age and gender. Patients with severe dementia, those having fewer than 10 teeth or those who were in need of antibiotic prophylaxis were excluded from the study. Patients underwent a short interview and a clinical evaluation. Our study involved 32 elderly adults with NIDDM and 40 elderly adults who did not have NIDDM. Both groups had similar oral hygiene levels and regularity of professional dental care. In addition, the plasma glucose levels among the study group were well controlled. This study did not show statistically significant differences in oral health parameters between participants with diabetes and those in a control group.

Coronary heart disease and periodontitis -- a case control study in Chilean adults

OBJECTIVES

To investigate the association between periodontal disease parameters and coronary ischemic disease among 30-50-year-old Chileans.

MATERIAL AND METHODS

Cases were 30-50-year-olds who were hospitalized in one of four Cardiologic Units in Santiago, Chile, for acute myocardial infarction, unstable angina or angina pectoris. Controls had undergone surgery due to gall bladder stones or abdominal hernia. Information on blood pressure, serum cholesterol, body weight and height, age, occupation, smoking, diabetes and use of antidepressants was obtained. A total of 86 persons participated based on informed consent, but the analysis is based on 61 persons, for whom a complete set of data was obtained. Cases and controls were given a clinical periodontal examination comprising assessment of number of teeth present, periodontal pocket depth and clinical attachment level at six sites per tooth. The association between mean attachment level; mean pocket probing depth; number of teeth present and case status was analyzed by conditional logistic regression controlling for known risk factors for CHD.

RESULTS

The mean attachment level was positively associated with case status (OR = 3.17; 95% CI = [1.31; 7.65]), as was the mean pocket depth (OR = 8.64; 95% CI = [1.22; 61.20]). The number of teeth present was not statistically significantly associated with case status (OR = 0.93; 95% CI = [0.83; 1.04]).

CONCLUSION

The results are in accordance with those of several previous reports. If the results reflect a causal link between periodontal diseases and CHD they emphasize the need for better control of periodontal diseases. If the associations are-non-causal, they still demonstrate that CHD and periodontal diseases cluster in the same sections of the population, which is important from a public health point of view.

Invasion of vascular cells in vitro by Porphyromonas endodontalis

AIM

The objective of this study was to determine whether laboratory strains and clinical isolates of microorganisms associated with root canal infections can invade primary cultures of cardiovascular cells.

METHODOLOGY

Quantitative levels of bacterial invasion of human coronary artery endothelial cells (HCAEC) and coronary artery smooth muscle cells (CASMC) were measured using a standard antibiotic protection assay. Transmission electron microscopy was used to confirm and visualize internalization within the vascular cells.

RESULTS

Of the laboratory and clinical strains tested, only P. endodontalis ATCC 35406 was invasive in an antibiotic protection assay using HCAEC and CASMC. Invasion of P. endodontalis ATCC 35406 was confirmed by transmission electron microscopy.

DISCUSSION

Certain microorganisms associated with endodontic infections are invasive. If bacterial invasion of the vasculature contributes to the pathogenesis of cardiovascular disease, then microorganisms in the pulp chamber represent potential pathogens.

Oral health and cardiovascular disease in Sweden

OBJECTIVE

The purpose of the present study was to assess the relation between dental health and cardiovascular disease in an adult Swedish population.

MATERIAL AND METHOD

A questionnaire was sent to 4811 randomly selected Swedes. It contained 52 questions about dental care habits, oral health, cardiovascular disease and their socio-economic situation. Odd ratios for all cardiovascular diseases (CVD) and the subgroup myocardial infarction, stroke and high blood pressure were calculated with a logistic regression model adjusted for age, gender, smoking, income, civil status and education. These ratios were calculated for subjects > or =41 years since few people suffer from CVD before this.

RESULTS

The national questionnaire was answered by 2839 (59%) people between 20-84 years of age and, of them, 1577 were 41 years of age or more. We found a significant association between self-reported bleeding gums (odds ratio 1.60, p=0.0017), presence of dentures (odds ratio 1.57, p=0.0076) and known CVD, which has also been reported in international studies. However, no association between loose teeth, deep pockets and known CVD was detected.

CONCLUSION

The results indicate that oral health and, especially gingival inflammation is associated with CVD.

Assessment of key elements to determine causation and risk factors in dentistry

The best research method for assessing therapeutic modalities is the RCT. The prospective nature and the randomization of the subjects in an RCT provide the greatest opportunity to control bias and offer the most valid answer to the clinical question. Observational studies generate hypotheses about causation and should be viewed as a first step in the continuum of health care delivery. The preponderance of evidence will mount as the hypotheses are tested by additional prospective, longitudinal, observational trials. The clinician's involvement is to design and implement therapeutic strategies to alter the causal exposure, intervene in the dose-response gradient, and block the pathophysiologic mechanisms. Dentistry is an art and a science. Moving through the continuum from causation hypothesis to therapeutic intervention is the science of dentistry. It is the science of dentistry that will change the scope of the profession in this millennium.

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.

Oral health care in the 21st century: implications for dental and medical education

The past decade has been turbulent for dental education, marked by debate about the future directions of the curriculum and the profession itself. The bulk of the dental school curriculum is still devoted to tooth restoration or replacement techniques, although the need for these procedures has declined. Some dental educators now advocate an oral physician model as the desired direction for the profession, with expanded training in systemic disease pathophysiology and a practice scope that extends beyond exclusive focus on the teeth and supporting structures. Proponents of this model contend for curriculum time with faculty who desire to maintain a technical focus. The outcome of this curricular tug-of-war has implications for medical education, because many oral health problems now fall into the overlapping educational and patient care environments of physicians, dentists, and other health care providers. Will physicians perceive the new dentist as an encroachment on territory or as a resource to enhance patient care? Within dentistry, the traditions of tooth restoration and prosthodontics shape the profession's culture. Are dental educators ready to reconfigure a curriculum that is deeply intertwined with the professional identity of 150,000 U.S. dentists practicing today? To stimulate thinking about these issues, the authors analyze the responses of dental education to changes in the public's oral health and to calls for curricular reform, propose strategies for modifying the way dentists are prepared for their professional responsibilities, and explore the sociology of change in academic institutions, because elements of dental education targeted for reform are revered components of school culture.

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.

Periodontal infections and cardiovascular disease--how strong is the association?

In the past decade there has been renewed interest in the old hypothesis that infections increase the risk of developing cardiovascular disease and stroke. There is now a convincing body of evidence that atherosclerosis has a major inflammatory component and is much more than the simple vascular accumulation of lipids. Infectious agents that have been linked to an increased risk of coronary heart disease (CHD) include Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus, and herpesviruses. The concept has emerged that each of these agents is an independent risk factor for CHD and that common chronic infections are important. In addition, periodontal infections have also been implicated as one of several factors contributing to the development of CHD. Evidence supporting a causative role of chronic infections in CHD is largely circumstantial. However, the evidence is sufficiently strong to warrant further examination of the possible link between chronic infections and CHD. In this review the lines of evidence for a causative role of C. pneumoniae in the development of CHD are summarized and contrasted with the lines of evidence suggesting a periodontal infection--CHD association. If common or widespread chronic infections are truly important risk factors for CHD, it is unlikely that a single infection will be shown to be causative. It is likely that the entire microbial burden of the patient from several simultaneous chronic infections is more important (e.g., H. pylori-caused gastric ulcers + C. pneumoniae-caused bronchitis + periodontitis). Increased cooperation between cardiologists and periodontists will be required to determine if, and what, combinations of common chronic infections are important in the pathogenesis of CHD and stroke.

Relationship between upper body obesity and periodontitis

Upper body obesity, related to visceral fat accumulation, is known to increase the risk of various adult diseases, especially type 2 diabetes and cardiovascular disease. This study was conducted to clarify the relationship between upper body obesity and periodontitis. We studied 643 apparently healthy, dentulous Japanese adults who attended programs at Fukuoka Health Promotion Center. Waist-hip ratio, body-mass index (BMI), and body fat were significant risk indicators for periodontitis after adjustment for known risk factors (p < 0.002). Subjects were divided into four BMI (or body fat) categories. In only the subjects with high waist-hip ratio, higher categories of BMI (or body fat) significantly increased the adjusted risk of periodontitis, compared with subjects with low waist-hip ratios and the lowest category of BMI (or body fat). The reported relationship between cardiovascular disease and periodontitis should be reconsidered, since abdominal adiposity or visceral fat can be related to both diseases.

Relationship between tooth loss and electrocardiographic abnormalities in octogenarians

Recent reports have suggested that periodontal disease is a risk factor for coronary heart disease (CHD). However, little is known about the relationship between periodontal disease and CHD in the very elderly. Therefore, we evaluated the association between tooth loss and abnormal ECG findings in octogenarians. Of the 1,282 octogenarians in Fukuoka Prefecture, Japan, 697 participated. Oral examinations--including a tooth count and an assessment of the Community Periodontal Index--and a 12-lead ECG were performed. Logistic regression analysis revealed that individuals with < 20 teeth had increased prevalence of ST segment depression, and T-wave abnormalities, after we adjusted for gender, smoking, serum cholesterol and glucose, blood pressure, and body mass index. Compared with individuals with > or = 20 teeth, edentulous individuals had an increased prevalence of T-wave abnormalities and arrhythmias after adjustment for coronary risk factors. We conclude that tooth loss may be an independent predictor of abnormal ECG findings in octogenarians.