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Failure to brush your teeth twice a day increases risk of heart disease

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Never mind your dentist. Your cardiologist might want you to brush your teeth more often.

Neglecting to brush twice a day could lead to a 70 percent increased risk of cardiovascular disease, according to a new large population-based study.

Researchers examined self-reported oral hygiene habits and coronary disease in 11,869 adults aged 35 and older (with a mean age of 50) from the Scottish Health Survey—a study conducted once every three to five years—between the years 1995 and 2003. The team, led by Cesar de Oliveira, a research fellow in epidemiology and public health at University College London, followed up with subjects after an average of eight years to see if they had had a heart attack or coronary disease.

Even though the researchers found that those who reported brushing their teeth less than twice a day were more likely to be male, older, smokers and to have other health issues (such as diabetes, hypertension and obesity), the team controlled for those variables and others and still found that tooth brushing is associated with cardiovascular disease. The association held even after adjusting for socioeconomic group, visits to dentist, BMI, family history of cardiovascular disease, hypertension and diagnosis of diabetes.

The findings were published online May 27 in the British Medical Journal.

Many previous studies have found a similar link, although other data have shown more modest increases in risk. One study from 2000, however, failed to find a convincing link between periodontitis and chronic coronary disease in a study of more than 8,000 people followed for 20 years. But the authors of the new paper noted that having periodontal disease increases the risk of getting cardiovascular disease in the future by 19 percent (that figure jumps to 44 percent for people who have periodontal disease before they are 65). That level of risk increase could "have a profound public health impact," the authors noted.

Although the study isn't proof of causation, the researchers highlight inflammation as a possible mechanism behind the link between periodontal disease and heart disease.

Chronic inflammation—and the body's response to it—is thought to be a factor for heart disease, and as the authors noted, periodontal disease "is one of the most common chronic infections and is associated with a moderate systemic inflammatory response."

As part of the study, de Oliveira and colleagues also tested blood samples from 4,830 of the survey subjects for two key inflammatory markers (C reactive protein and fibrinogen). They found a strong association between poor oral hygiene routines and high levels of these markers, suggesting inflammation as a possible link between oral and heart health. The possibility should be enough, the authors noted, to suggest that, "doctors should be alert to the possible oral source of an increase inflammatory burden." And it might just be another reason for people to brush more often.

Image courtesy of iStockphoto/diego_cervo