Tip of the Day!
Dangers of a Toothless
Grin!
Poor dental health may raise
stroke risk
By Jennifer Warner
Dec. 12, 2002 -- Losing your teeth may do more than just sacrifice your smile. A new study suggests tooth loss may increase the risk of stroke by as much as 74% compared with those who have a healthy mouthful of teeth.
The findings add more evidence to support the growing link between gum (periodontal) disease, which is caused by bacterial infections, and the risk of stroke and heart disease. Recent studies have shown that infections play a complex and important role in increasing the risk of these problems.
But researchers say this study is unique because it shows an association between tooth loss and heightened stroke risk that was over and above the risks associated with gum disease alone. It found men with fewer than 25 teeth at the start of the study had a 57% higher risk of the most common type of stroke caused by a blockage or blood clot in an artery leading to the brain (ischemic stroke) compared with men who have more than 25 teeth.
The study appears in Stroke: Journal of the American Heart Association.
According to the American Dental Association, adults normally have 32 teeth, including four wisdom teeth, which are often removed if they cause problems in early adulthood.
In the study, researchers looked at 41,380 healthy men who were involved in the Health Professional's Follow-Up study, which consisted of mostly white dentists, veterinarians, pharmacists, optometrists, and other health professionals who were between the ages of 40 and 70 at the start of the study. During 12 years of follow-up, 349 clot-related strokes occurred among the men.
Compared with men with the most teeth, researchers found that men with 17 to 24 teeth had a 50% higher risk of stroke, and that increased risk rose to 74% among men with 11 to 16 teeth.
Researcher Kaurmundi J. Joshipura, BDS, ScD, associate professor of epidemiology at Harvard School of Public Health, says participants with fewer teeth tended to be older, drank more alcohol, were less physically active, and more likely to smoke than the others. But researchers were surprised to find that the association between tooth loss and stroke risk was higher among nonsmokers than among smokers.
Smoking is known to increase the risk of both gum disease and stroke, but Joshipura says the higher risk found among nonsmokers suggests the link between tooth loss and stroke isn't completely due to tobacco use.
Researchers also looked at whether differences in diet might explain the link between tooth loss and stroke.
"When people lose teeth, they may eat fewer fruits and vegetables,'" Joshipura says in a news release. "And that, in turn, might affect their stroke risk. However, the results suggested that the dietary factors evaluated did not seem to play an important role in the association between tooth loss and stroke found in this study."
Previous studies on tooth loss and stroke risk have produced conflicting results, and the researchers say more research is needed to fully understand the link. But they say a strength of this study is that they looked at a group of health professionals who tended to be very similar in terms of education, socioeconomic status, and health behavior.
"They would be doing more things to keep themselves healthy, whether that is for their overall health, dental health, or cardiovascular health. So if we find an association in this kind of population, it is more likely that it is causal," says
Joshipura.
SOURCES: Stroke: Journal of the American Heart Association, Dec. 12, 2002 • News release, American Heart Association • American Dental Association.
|