Clinical Context

Periodontitis has been associated with a higher risk for cardiovascular disease among adults, and a joint working group from the European Federation of Periodontology and American Academy of Periodontology addressed this issue in a statement published in the April 2013 issue of the Journal of Periodontology.

The group found clear evidence from multiple studies that periodontitis was associated with an increased risk for cardiovascular disease that went beyond that associated with more traditional cardiovascular risk factors. This relationship was evident among women and men and in different age groups.

There were far fewer data on how the treatment of periodontitis might influence the risk for cardiovascular events. The group found moderate evidence that the treatment of periodontitis improved markers of systemic inflammation as well as measures of endothelial function. However, they found no studies that assessed periodontal treatment in the primary prevention of cardiovascular events, and there was only 1 low-quality study of treatment of periodontitis for secondary prevention.

The systemic inflammation associated with periodontitis may also represent a risk factor for cancer. The current study addresses this issue.

Study Synopsis and Perspective

Severe gum disease may increase not only the risk for cancer, including lung and colorectal cancer, but also the likelihood of dying of the disease, particularly pancreatic cancer, suggest results from 2 large-scale studies from the United States and Finland.

The US study, led by Dominique Michaud, ScD, professor of public health and community medicine at Tufts University School of Medicine, Boston, Massachusetts, included almost 7500 individuals who had undergone dental examination. Of them, more than 1600 developed cancer.

The findings, which were published online in the Journal of the National Cancer Institute on January 12, showed that severe periodontitis was associated with a 24% increased risk for cancer, with the highest risks seen for lung cancer and colorectal cancer.

“This is the largest study addressing the association of gum disease and cancer risk using dental examinations to measure gum disease prior to cancer diagnosis,” Dr Michaud said in a statement.

“Additional research is needed to evaluate if periodontal disease prevention and treatment could help alleviate the incidence of cancer and reduce the number of deaths due to certain types of cancer,” he added.

Although also acknowledging the need for more work on, for example, the racial disparities they identified in the study, the team believe that their findings underline the need for expanded access to dental insurance.

Study coauthor Elizabeth Platz, ScD, from Johns Hopkins Bloomberg School of Public Health and the Johns Hopkins Kimmel Cancer Center, Baltimore, Maryland, said, “Knowing more about the risks that come about with periodontal disease might give more support to having dental insurance in the way that we should be offering health insurance to everyone.”

In the second study, lead author Timo Sorsa, DDs, PhD, from the University of Helsinki and Helsinki University Central Hospital, Finland, and colleagues examined registry data on more than 68,000 adults who had made a primary dental healthcare visit.

This revealed that periodontitis was associated with a 33% increased risk for overall cancer mortality. The mortality risk associated with gum disease among individuals with pancreatic cancer was far higher, with a more than 2-fold increased risk.

The study was published in the International Journal of Cancer on January 11.

Dr Sorsa and colleagues also refer to another study they conducted, recently published in the British Journal of Cancer, which shows that a virulence factor associated with a bacterium seen in periodontitis also occurs in gastrointestinal tumors.

“These studies have demonstrated for the first time that the virulence factors of the central pathogenic bacteria underlying gum disease are able to spread from the mouth to other parts of the body, most likely in conjunction with the bacteria, and take part in central mechanisms of tissue destruction related to cancer,” Dr Sorsa said in a statement.

As a consequence, the prevention and early diagnosis of periodontitis could be important for not only oral health but also overall well-being.

“In the long run, this would be extremely cost-effective for society,” said Dr Sorsa.

 

Largest Study Based on Dental Exam

To date, most studies looking at the association between periodontitis and cancer risk have relied on self-reports. In contrast, the study conducted by Dr Michaud and colleagues included a dental examination.

The team used data from the Atherosclerosis Risk in Communities study cohort, a prospective analysis of 15,792 individuals aged 44 to 66 years who were recruited from 4 areas of the United States between 1987 and 1989.

All the participants took part in a baseline examination, followed by 3 follow-up visits over the course of 10 years. At the fourth visit, the remaining participants were invited to undergo a clinical dental examination that probed depth and gingival recession at 6 sites.

Via linkage to state cancer registries, supplemented by medical records and hospital discharge codes, the team assessed the cancer incidence between 1987 and 2012; cancer deaths were obtained from death certificates.

Ruling out participants with a cancer history, the team included in the current analysis 6056 individuals who underwent the dental examination and 1410 who had no teeth (ie, were edentulous).

Depending on the definition used, 2420 to 2543 individuals had no or mild periodontitis, whereas 2104 to 2514 had moderate periodontitis and 1122 to 1409 had severe periodontitis.

More severe periodontitis, regardless of the definition of severity used, was associated with being older, male, black, less educated, obese, and a smoker.

During a mean follow-u