Heart attack survivors who suffer advanced gum disease show significantly higher levels of a protein in their blood called C-reactive protein (CRP) than such patients without gum disease, new University of North Carolina at Chapel Hill research indicates.
The findings, presented Sunday (Nov. 12) during a news conference at the annual American Heart Association meeting in New Orleans, suggest that the presence of gum disease might increase the risk of a second heart attack in people with a history of heart disease.
"Not only did the heart attack patients with periodontal disease have higher levels of CRP than those without gum disease, but the CRP levels were directly related to the severity of the gum disease," said Dr. Efthymios N. Deliargyris, an interventional cardiologist and a member of the Center for Oral and Systemic Diseases at UNC-CH. "The more severe the gum disease, the higher the CRP levels."
Besides Deliargyris, also an instructor in medicine at the UNC-CH School of Medicine, study investigators were Drs. Steven Offenbacher, professor of periodontology and center director, James D. Beck, professor of dental ecology, both at the UNC-CH School of Dentistry, and Sidney C. Smith Jr., chief of cardiology and past president of the American Heart Association.
"We know a lot of risk factors for heart attacks, including high blood pressure, high cholesterol, diabetes and cigarette smoking, but all those combined only explain about two-thirds of heart attacks," Deliargyris said. "Since about a third of people who suffer heart attacks don’t have those risk factors, there’s a wide search going on for other conditions that may contribute to increased risk."
Studies at UNC-CH and elsewhere have linked periodontal disease -- an advanced form of gingivitis -- with increased risk of heart attacks, but it has been unclear what the two conditions have in common, the physician said.
"The one thing we know the two conditions share is that they tend to initiate an immune response, also called an inflammatory response, in the body," he said. "The most common marker for this response is this C-reactive protein, which is considered predictive of future adverse events like heart attack."
To learn how common severe gum disease was in heart attack victims, the UNC-CH team conducted their pilot study of 38 heart attack patients and matched them with a comparable group of 38 other people without known heart disease. Researchers found a high percentage of the former had periodontal disease -- 85 percent -- as compared with only 29 percent of the controls.
"The most exciting finding was that among people with a heart attack, those with periodontal disease had much higher CRP levels than those with a heart attack but no periodontal disease," Deliargyris said. "It seems that the presence of periodontal disease on top of a heart attack has a synergistic effect and a very accentuated CRP release."
Despite its small size, the study findings are the first of their kind and potentially very important, he said.
"This gives us an insight into possible mechanisms underlying the association between gum disease and heart disease," Deliargyris said. "Now we believe that patients with a heart attack and periodontal disease have an exaggerated inflammatory response with higher CRP levels that might put them at risk for future heart attacks. This work also raises the possibility that by treating severe gum disease in people with heart attacks, we might be able to reduce their CRP levels and their risk of another heart attack."