New link between gum and cardiovascular diseases

Virginia Commonwealth University researchers have found that changes in the plasma lipoprotein profile of patients with severe periodontitis – a condition characterized by chronic infection and inflammation of the gums – may contribute to these patients’ elevated risk for heart disease and stroke.

The findings suggest that it may be beneficial to test periodontitis patients for changes in their plasma lipoprotein profiles, so that available medication can be taken if necessary.

In the December issue of the Journal of Lipid Research, researchers found that patients with generalized aggressive periodontitis generally had elevated plasma levels of a particularly bad subclass of the low density lipoprotein (LDL) called small-dense LDL.

“Previous research has shown that people who have predominantly small-dense LDL in their blood are at a three- to six-fold increased risk of heart disease and stroke”, said lead author Rik van Antwerpen, Ph.D., an assistant professor of biochemistry at VCU. “A person may have predominantly small-dense LDL without having alarmingly high blood levels of cholesterol. Therefore, unhealthy levels of small-dense LDL are not always detected in regular cholesterol tests.”

According to the study, a second factor influencing the cardiovascular risk of patients with severe periodontitis may be platelet activating factor acetylhydrolase (PAF-AH), an enzyme that is associated with small-dense LDL. PAF-AH is able to break down some of the inflammatory, atherogenic components of LDL. Van Antwerpen said that the enzyme may lower the atherogenic effects of LDL, and that the observed decrease of LDL-associated PAF-AH activity in patients with severe periodontitis may increase the cardiovascular risk of these patients.

“Our results indicate that these differences may in part be responsible for the enhanced plaque build up in the arteries of patients with severe periodontitis,” said van Antwerpen.

In this study, a limited number of participants were enrolled – 12 patients with generalized aggressive periodontitis and 12 control subjects without periodontal disease. Currently, van Antwerpen and his colleagues are evaluating a greater number of patients with varying degrees of periodontal infection and inflammation as they work toward establishing testing guidelines for periodontitis patients.

This research was supported by grants from the National Institutes of Health.

Van Antwerpen collaborated with Harvey A. Schenkein, Ph.D., Director of the Clinical Research Center for Periodontal Diseases, and chair of the Department of Periodontics, VCU School of Dentistry; Suzanne E. Barbour, Ph.D., associate professor in the Department of Biochemistry, VCU School of Medicine; John G. Tew, Ph.D., professor in the Department of Microbiology and Immunology, VCU School of Medicine. Experiments were carried out by Miguel Rufail, a graduate student in the VCU Department of Biochemistry.