For over twenty years, studies have shown a link between poor oral health and coronary heart disease. One such study showed a 25% increased risk of heart disease in individuals with periodontitis (gum disease) (DeStefano et. al, 1993). Recent studies have shown additional risks: one study showed participants with greater amounts of plaque on their teeth correlated with a 4.43-fold increased occurrence of infective endocarditis, an inflammation of the inner layer of the heart (Lockhart et. al, 2009).
But how is it that brushing and flossing decrease chances of heart problems?
No one is quite sure yet, but there are two leading theories.
Firstly, experts know that bacteria in the mouth can enter the bloodstream through the gums. This occurs when tiny cuts, caused by eating, brushing and flossing allow the bacteria to get into the bloodstream. Bacteria from the mouth travel through the circulatory system and stick to fatty plaques in the bloodstream, contributes to blockages. Large numbers of bacteria have been found clumped in artery plaques (Griffin, 2000). Bacteria may also be able to travel directly to the heart and infect the inner layer (Lockhart et. al, 2009).
The other theory focuses on the body’s defense mechanism against the bacteria. Inflammation is one of the primary responses of the body’s immune system. When bacteria from the mouth enter the bloodstream, arteries and blood cells become inflamed. The swelling causes the blood vessels to narrow, increasing the risk of clots (Griffin, 2000). In the case of gum disease, the inflammation would become chronic, increasing the risk of heart attack and stroke (Is Flossing Good For Your Heart?, 2000).
One of the issues in identifying the connection between periodontitis and heart disease is that individuals commonly affected by one disease also have the other – but the two illnesses may be unrelated. The most common group affected often had other contributing factors to heart disease including diabetes, high blood pressure, high cholesterol, and smoking (Is Flossing Good For Your Heart?, 2000). The difference between causation and correlation becomes apparent in these studies.
Regardless, doctors still advocate for maintaining good oral hygiene. Routine brushing and flossing decreases damage done to the gums by the bristles of the toothbrush and material of the floss. It also decreases the number of bacteria in the mouth. “It’s fairly easy to do,” says Gordon Douglass, DDS, “and why not get rid of a potential risk factor for heart disease?” (Griffin, 2000)
References:
DeStefano, F., Anda, R.F., Kahn, H.S., Williamson, D.F., Russell, C.M. (1993). Dental disease and risk of coronary heart disease and mortality. British Medical Journal, 306(6879), 688-91.
Griffin, R.M. & Chang, L. (Ed.) (2000). Gum disease and heart health: Brushing and flossing may actually save your life. Web MD. Retrieved from: http://www.webmd.com/heart-disease/features/periodontal-disease-heart-health
Is flossing good for your heart? (10 September, 2000). Web MD. Retrieved from: http://www.webmd.com/heart/news/20000919/is-flossing-good-for-your-heart
Lockhart, P.B., Brennan, M.T., Thornhill, M., Michalowicz, B.S., Noll, J., Bahrani-Mougoet, F.K., Sasser, H.C. (2009). Poor oral hygiene as a risk factor for infective endocarditis-related bacteremia. Journal of the American Dental Association, 140(10), 1238-44.
The connection between oral health and cardiovascular health has recently been gaining a lot of attention, and the cause and effect relationship was interesting to me. It seems as though the two leading theories are centered around bacteria, which certainly makes sense, but maybe other factors are playing a role.
ReplyDeleteAs you stated, one of the biggest limitations is that most people often have both problems. I found a paper in which they studied the state of gingival disease in 75 patients, and its correlation to the hormone leptin. As the gingival disease progressed, it actually led to a significant increase in plasma leptin levels(1).
Leptin is a hormone produced by adipose tissue, and is essentially an indicator of the amount of fat in the body. Fat cells will release leptin when they are "sufficient in energy"(2). The data from the paper shows that progression of gingival disease, or worse oral health, induces another mechanism that causes increased storage of fat. Increased fat, of course, would directly correlate to an increased risk in cardiovascular disease by increasing the amount of LDLs and cholesterol in the blood(3).
Prasad et al also makes an interesting point that as research continues, and assuming the correlation between oral health and cardiovascular disease becomes more prominent, oral healthcare professionals (primarily dentists) will have to be trained to identify patients in serious risk of cardiovascular disease(3).
In my opinion, although there might be a connection via physiological/biochemical mechanisms between oral health and heart health, I believe there is a more basic explanation. DeStefano et al did not find a clear correlation between dental disease and coronary heart disease, and claims that dental health may be an indicator of hygiene and health care practices(4). Essentially, those that take care of their oral hygiene are more likely to take care of themselves and be more healthy. A healthy lifestyle, to this day, is the best way to minimize the risk of cardiovascular disease. And I believe that oral health is just another way of measuring that lifestyle.
References:
(1) http://www.ncbi.nlm.nih.gov/pubmed/22124048
(2) http://www.webmd.com/diet/features/the-facts-on-leptin-faq
(3) http://www.ncbi.nlm.nih.gov/pubmed/21760667
(4) http://www.ncbi.nlm.nih.gov/pubmed/8471920
While working in the dental office I experienced firsthand risks associated with poor oral hygiene and affects on coronary heart disease (CHD). Each week we would treat several patients that required premedication in form of antibiotics prior to most dental procedures.
ReplyDeleteHistorically, premedication was required for most cardiovascular conditions, but recently the American Heart Association with American Dental Association released new guidelines for antibiotic premedication. Antibiotic premedication is no longer required for dental patients with rheumatic heart disease and other heart conditions, such as ventricular and atrial septal defects, among several others.
Premedication however remains in effect for patients with artificial heart valves, history of infective endocarditis, unrepaired cyanotic congenital heart disease and patients with cardiovascular prosthetic devices placed in the past 6 months (Rethman, 2007).
Such a change in premedication practices of the past half-century was a result of better understanding risks associated with possible allergic reactions to antibiotics. Furthermore, recent reviews found no significant benefits of premedication for dental patients with certain health conditions. Finally and most importantly, multiple studies discovered that oral bacteria have a continuous passage into bloodstream via daily activities such as chewing, thus having a healthy mouth in the first place greatly reduces amount of bacteria that could be disturbed. This supports the ongoing message that is being heard in dental offices about the significance of good daily oral hygiene practices at home.
References:
Rethman, M.P. (2007). New Guidelines for Antibiotic Premedication. Dimensions of Dental Hygiene, 5(5): 12-13.
Antibiotic Recommendations for Patients Requiring Premedication Before Dental Procedures. Retrieved from: http://www.hdnds.org/aha.html