May 27, 2010
Toothbrushing Good For The Heart
Brush away some of your risks of heart disease.
Individuals who have poor oral hygiene have an increased risk of heart disease compared to those who brush their teeth twice a day, finds research published today on BMJ.com.
In the last twenty years there has been increased interest in links between heart problems and gum disease. While it has been established that inflammation in the body (including mouth and gums) plays an important role in the build up of clogged arteries, this is the first study to investigate whether the number of times individuals brush their teeth has any bearing on the risk of developing heart disease, says the research.
Toothbrushing isn't just about cavities and breath smell.
Once the data were adjusted for established cardio risk factors such as social class, obesity, smoking and family history of heart disease, the researchers found that participants who reported less frequent toothbrushing had a 70% extra risk of heart disease compared to individuals who brushed their teeth twice a day, although the overall risk remained quite low. Particpants who had poor oral hygiene also tested positive for inflammatory markers such as the C-reactive protein and fibrinogen.
Chronic bacterial infection can cause chronic inflammation which sets in motion processes that lead to clogged arteries, heart attacks, and stroke.
Flossing will probably help even more than brushing. Regular teeth cleaning appointments will help too.
Are healthier people more likely to brush more frequently?
Jim - I was wondering the same thing. Perhaps unhealthy people are more likely to engage in bad habits like brushing and eating fatty foods.
Yeah, you really shouldn't make this kind of claim about correlational studies... People who brush their teeth are also health =/= If you brush your teeth you will be healthy (causation direction, third variable problem, etc.). Seriously.
Did you guys see the part of the article that said "Once the data were adjusted for established cardio risk factors such as social class, obesity, smoking and family history of heart disease, the researchers found..."? It sounds to me like they adjusted for the stuff you want them to adjust for.
Correlation is not causation. Jeez.
I remember reading an article a couple of years ago that said that the bacteria that flourish when you have gum disease excrete toxins that get into the bloodstream and can damage the heart muscle. So apparently that's the correlation, or causation.
No, adjusting for "social class, obesity, smoking and family history of heart disease" -- or any other proven or suspected factors -- does not eliminate the separate factor, that people self-select for brushing twice a day, and that this is likely to correlate positively with their self-selection for other healthy behaviors, some of which are not on any finite list of factors the researchers do adjust for. Even with random assignment correlation does not prove causation, though it often will prove probable; but with self-selection, the results are almost useless. One could design a study where doctors are urged to emphasize dental care to a random selection of heart patients, and with proper followup this would provide much more meaningful data.
I'm really going to stop reading FuturePundit if Randall continues to post such studies without addressing correlation bias.
Sometimes I do not address correlation bias because I'm posting on a topic with a huge body of literature supporting the same conclusions as the latest report. I'm basically posting as a reminder. In this case I'm posting to remind people to brush and floss and get their teeth clean.
The idea that periodontal disease contributes to heart disease is very well established. For example, from a research report in 2002:
Researchers found diseased gums released significantly higher levels of bacterial pro-inflammatory components, such as endotoxins, into the bloodstream in patients with severe periodontal disease compared to healthy patients. As a result, these harmful bacterial components in the blood could travel to other organs in the body, such as the heart, and cause harm.
The study is in line with recent findings by the University of Buffalo where researchers suggest periodontal disease may cause oral bacterial components to enter the bloodstream and trigger the liver to make C-reactive proteins, which are a predictor for increased risk for cardiovascular disease.
"We found the mouth can be a major source of chronic or permanent release of toxic bacterial components in the bloodstream during normal oral functions," said Dr. E.H. Rompen, director of the study. "This could be the missing link explaining the abnormally high blood levels of some inflammatory markers or endotoxemia observed in patients with periodontal disease."
Here's the abstract from a meta-analysis published in 2008: (my bold emphasis added)
BACKGROUND: Periodontal disease is common among adults in the US and is a potential source of chronic inflammation. Recent data have suggested an important role for chronic inflammation in the development of coronary heart disease (CHD). OBJECTIVE: To aid the United States Preventive Services Task Force (USPSTF) in evaluating whether periodontal disease is an independent novel risk factor for incident CHD. METHODS: Studies were identified by searching Medline (1966 through March 2008) and reviewing prior systematic reviews, reference lists, and consulting experts. Prospective cohort studies that assessed periodontal disease, Framingham risk factors, and coronary heart disease incidence in the general adult population without known CHD were reviewed and quality rated using criteria developed by the USPSTF. Meta-analysis of good and fair quality studies was conducted to determine summary estimates of the risk of CHD events associated with various categories of periodontal disease. RESULTS: We identified seven articles of good or fair quality from seven cohorts. Several studies found periodontal disease to be independently associated with increased risk of CHD. Summary relative risk estimates for different categories of periodontal disease (including periodontitis, tooth loss, gingivitis, and bone loss) ranged from 1.24 (95% CI 1.01-1.51) to 1.34 (95% CI 1.10-1.63). Risk estimates were similar in subgroup analyses by gender, outcome, study quality, and method of periodontal disease assessment. CONCLUSION: Periodontal disease is a risk factor or marker for CHD that is independent of traditional CHD risk factors, including socioeconomic status. Further research in this important area of public health is warranted.
Given the accumulating and very large body of evidence that sees inflammation is playing a key role in artery clogging and periodontal disease's role in causing inflammation it is no surprise that heart and dental researchers are collaborating on this. By 2009 the consensus on the causative link had become pretty strong:
Q. Is there a link between heart disease and gum disease?
A. There is growing evidence that there is, indeed, such a link, and if you have either condition, you should pay extra attention to treating the other as well. That’s the conclusion of a “consensus’’ statement written by leading gum disease specialists and cardiologists published online earlier this year in the American Journal of Cardiology and the Journal of Periodontology.
“The mechanism of the relationship strongly points to inflammation’’ as the culprit in both cardiovascular disease and periodontitis, or gum disease, says Dr. Thomas E. Van Dyke, a professor of periodontology and oral biology at the Boston University School of Medicine.
I can dig up tons of reports supporting a causative link. It has been heavily studied.
Here's a previous post I did on it in 2006.