POSTMENOPAUSAL WOMEN WITH PERIODONTAL DISEASE ARE MORE LIKELY TO DEVELOP BREAST
CANCER THAN WOMEN WHO DO NOT HAVE CHRONIC INFLAMMATORY GUM DISEASE.
ined the associations stratified by
smoking status.
After a mean follow-up time of 6.7
years, 2,124 women were diagnosed with breast cancer. The
researchers found that among all
women, the risk of breast cancer
was 14 percent higher in women who
had periodontal disease.
Among women who had quit smoking
within the past 20 years, those with periodontal disease had a 36 percent higher risk of breast
cancer. Women who were smoking at the time of this study had
a 32 percent higher risk if they had periodontal disease, but
the association was not statistically significant. Those who
had never smoked or had quit more than 20 years ago had
a 6 percent and 8 percent increased risk, respectively, if
they had periodontal disease.
Freudenheim said the fact that the highest risk was found
in the smokers who had quit within the past 20 years may
indicate that previous exposure to smoking affected the carcinogenic process, and that the effects of smoking were slow
to be reversed. “We know that the bacteria in the mouths of
current and former smokers who quit recently are different
from those in the mouths of nonsmokers,” Freudenheim
explained.
One limitation of the study is that
women self-reported their periodontal
disease status, after being asked
whether a dentist had ever told them
they had it. Also, Freudenheim
pointed out that since her research
focused on women who were already
enrolled in a long-term national health
study, they were more likely than the
general population to be receiving regular
medical and dental care, and were likely
more health-conscious than the general population. She estimated that the general population would
have a higher rate of periodontal disease and other risk factors,
such as smoking, diabetes, and obesity.
This study was funded by the National Heart, Lung, and Blood Institute;
the National Institutes of Health; and the U.S. Department of Health and
Human Services. Freudenheim declares no conflicts of interest.
BREAST CANCER RISK WAS
14%
IN WOMEN WITH
PERIODONTAL DISEASE
There are several possible explanations for the link between
periodontal disease and breast cancer. One possibility is that
there is a systemic inflammation with periodontal disease that
affects the breast tissues. Another possible explanation is that
bacteria from the mouth can enter
the circulatory system and they
IN WOMEN WHO
affect breast tissues. However, furHAD QUIT SMOKING
ther studies are needed to establish
LESS THAN 20 YEARS AGO
a causal link, Freudenheim said.
AND HAD GUM DISEASE
“If we can study periodontal disease and breast cancer in other
populations, and if we can do more detailed study of the characteristics of the periodontal disease, it would help us understand if there i