Bacteria Behind Gum Disease Are Linked to Heart-Attack Risk
WSJ, B6, 9/30/03
Written by Marilyn Chase

San Diego - Chronic gum disease can lead to tooth loss, but now there is mounting evidence that it also can damage your heart.

Scientists at the Interscience Conference on Antimicrobial Agents and Chemotherapy here presented evidence showing how the bacteria involved in periodontal disease can promote the buildup of artery-clogging plaque, which can lead to heart attacks.

"The links are getting stronger," said Caroline Genco, associate professor at the Boston University School of Medicine. Other bacteria, including shlamydia, long have been implicated in cardiovascular disease. Epidemiological surveys and clinical studies of patients more recently implicated Porphyromona gingivalis, a bacterium linked to gum disease. But it wasn't clear how it acted.

In a study supported by grants from the National Institutes of Health, Dr. Genco put the bacteria into the mouth of mice who were genetically prone to develop heart disease. She then traced the bacteria as they spread from the mouth into the bloodstream and ultimately the aorta, where they caused inflammation and accelerated atheroscleerosis. It is a route vulnerable to bacterial invasion, she said.

"The oral cavity is a prime location for bacteria to become systemic, through bleeding that occurs when you brush your teeth, "Dr. Genco said. Such infection triggers chronic inflammation, which unleashes a cascade of molecular events that build up plaque and choke off arteries.

Dr. Genco doesn't believe disease alone is responsible, but it acts along with other smoldering infections-according to a recent theory called "multiple-pathogen burden" - that exacerbate well-known cardiac risk factors such as high cholesterol or smoking.

As a hedge against this added heart risk, she recommends good oral hygiene and prompt attention to symptoms such as bleeding gums.

A multicenter study also funded by NIH is under way to see whether periodontal treatments such as tooth scaling, gum cleaning and antibiotics can purge P, gingivalis and reduce associated risks.