By LINDSEY TANNER, AP Medical Writer
CHICAGO (AP) – Floss-haters, take heart.
A new study rebuts evidence suggesting that gum disease may lead to heart trouble.
That doesn’t mean gums shouldn’t be attended to by floss and brush. But the results question theories stemming from a growing area of research into the relationships among infection, inflammation and many diseases.
Some say the new study does not settle the issue.
Previous researchers have suggested that bacteria in the mouths of people with gum disease may create heart problems by causing clots to form in coronary arteries.
Others have theorized that substances released by the body in response to infection may also cause plaque buildup in arteries when the process – known as the inflammatory response – drags on indefinitely, as happens in chronic infections such as gum disease.
The theories have led some to reason that vigilant flossing and brushing could prevent not only gum disease but also heart disease.
But the lead author of the latest study, published in Wednesday’s Journal of the American Medical Association says his findings don’t support that idea.
“There is no evidence that any dental treatment will have a positive impact on chronic coronary heart disease, said researcher Philippe Hujoel, an associate professor at the University of Washington’s dentistry school.
If there is any link between gum disease and heart problems, it’s either “very small or very hard to reliably detect,” Hujoel said.
More than half of the U.S. adult population has either reversible gum disease, known as gingivitis, or periodontitis – advanced disease affecting the tissue and bone that support the teeth. Heart disease – the nation’s leading killer – affects an estimated 12 million Americans.
Dennis Mangan, chief of infectious diseases and immunity at the National Institute of Dental and Craniofacial Research, said the study “could change the way we take a look at this link between infectious disease and cardiovascular disease.”
Still, Mangan said the study doesn’t prove there is no connection and noted that upcoming University of North Carolina research suggests a link between heart disease and gum disease exists in women, but not men.
The contradictory findings “highlight the importance of continued investment in research in this area,” said Dr. Sidney Smith, an American Heart Association spokesman.
Hujoel and colleagues examined data on 8,032 adults aged 25 to 74 who participated in a national health study from 1982 to 1992. No participant had a history of heart disease but about half had mild or advanced gum disease.
During the study, 1,265 had at least one “coronary heart disease event,” including heart attacks, heart bypass surgery and hospitalization for heart disease.
Those with gum disease were all much more likely to be low-income, black, older and overweight. They also tended to suffer diabetes and high blood pressure, and to smoke cigarettes and drink alcohol – all heart disease risk factors.
While they also were more likely than those with healthy gums to develop heart disease, the link evaporated when the researchers factored in the other characteristics.
Hujoel said previous studies failed to control for the cardiovascular risk factors prevalent among people with gum disease.
Dr. Mark Herzberg of the University of Minnesota, whose research has found a gum disease-heart disease connection, said his findings remain “biologically possible.”
He said the new study shows other risk factors should not be discounted and give researchers “more guidance in the design of future studies.”