Researchers in England analyzed data from more than 11,000 people taking part in a study called the Scottish Health Survey. They examined lifestyle habits such as smoking, overall physical activity, and oral health routines.
Patients were asked whether they visited a dentist at least once every six months, every one to two years, rarely, or never. They were also asked how often they brushed their teeth -- twice daily, once a day, or less than every day.
The researchers found that:
- 62% of participants said they went to a dentist every six months.
- 71% said they brushed their teeth twice a day.
After adjusting the data for cardiovascular risk factors such as obesity, smoking, social class, and family heart disease history, the researchers found that people who admitted to brushing their teeth less frequently had a 70% extra risk of heart disease.
People who reported poor oral hygiene also tested positive for bloodstream inflammatory markers such as fibrinogen and C-reactive protein.
"Our results confirmed and further strengthened the suggested association between oral hygiene and the risk of cardiovascular disease," Richard Watt, DDS, of University College London, says in a news release. "Furthermore, inflammatory markers were significantly associated with a very simple measure of poor oral health behavior."
He says more studies are needed to confirm the findings and to determine whether oral health and cardiovascular disease are causal or simply risk markers.
The findings of the study were not necessarily shocking, the researchers say, because scientists have increasingly wondered about a possible connection between dental disease and cardiovascular health.
"Inflammation plays an important role in the pathogenesis of atherosclerosis, and markers of low grade inflammation have been consistently associated with a higher risk of cardiovascular disease," they write.
Poor oral hygiene is the major cause of periodontal disease, a chronic infection of the tissues surrounding the teeth. Thus, gum infections seem to add to the inflammatory burden on individuals, increasing cardiovascular risk, the researchers say.
Oral infections are common, so doctors should be alert to infections in the mouth as signs of increased inflammation, and tell patients to brush their teeth and maintain good oral hygiene, the researchers conclude.
The study is published in the journal BMJ.