Featured Research

from universities, journals, and other organizations

Tooth Loss Linked To Increased Stroke Risk

Date:
December 13, 2002
Source:
American Heart Association
Summary:
Tooth loss and periodontal disease may increase the risk of ischemic stroke, according to a report in the latest issue of Stroke: Journal of the American Heart Association.

DALLAS, Dec. 13 – Tooth loss and periodontal disease may increase the risk of ischemic stroke, according to a report in today's rapid access issue of Stroke: Journal of the American Heart Association.

Ischemic strokes result from a blockage in an artery leading to the brain. They are the most common type of stroke.

In the study, men who had fewer than 25 teeth when they entered the study had a 57 percent higher risk of ischemic stroke than those with 25 or more teeth.

The link between ischemic stroke and periodontal disease, which is caused by bacterial infections, adds another piece to the growing body of evidence that infection plays a role in stroke and heart disease. However, the new study presents a surprising finding about tooth loss.

"The association of ischemic stroke with tooth loss persisted even after we controlled for periodontal disease history, which could reflect severe periodontal disease in the extracted teeth," says Kaumudi J. Joshipura, BDS, Sc.D., an associate professor of epidemiology at Harvard School of Dental Medicine and Harvard School of Public Health in Boston.

Another unexpected – and unexplained – finding was that the association between tooth loss and stroke risk was higher among nonsmokers than among smokers. Smoking tobacco is a risk factor for both ischemic stroke and periodontal disease.

"We don't know why nonsmokers showed a higher association," Joshipura says. "But that lends support to the argument that the association between tooth loss and stroke is not all due to smoking."

The researchers also found that the risk of stroke was mainly related to the number of missing teeth at entry into the study, rather than teeth lost recently during the follow-up phase. This is possibly because only a few teeth were lost during follow-up or may imply that tooth loss takes many years to impact ischemic stroke risk, she says. This study is the first to examine the timing of tooth loss and the effect on stroke risk.

Periodontal disease, tooth loss and ischemic stroke share about a dozen risk factors, including age, smoking, diabetes, and some socioeconomic factors such as low income, Joshipura says.

Researchers studied 41,380 men in the Health Professionals' Follow-Up Study – mostly white dentists, veterinarians, pharmacists, optometrists, osteopathic physicians and podiatrists who were ages 40 to 75 at the start of the 12-year study. The men completed questionnaires mailed to them every two years about their medical history, health behaviors, and the occurrence of cardiovascular problems or other adverse health events.

Participants with fewer teeth were generally older, drank more alcohol, were less physically active and were more likely to smoke.

Researchers documented 349 ischemic strokes in the entire group. Compared to men with 25 to 32 teeth, those with 17 to 24 teeth had a 50 percent higher risk of stroke. Men with 11 to 16 teeth had a 74 percent higher risk and men with 10 or fewer teeth had a 66 percent higher risk of stroke compared to men with the most teeth.

Researchers studied whether the association between tooth loss and ischemic stroke could partly be the differences in diet, such as the amount of fruits and vegetables consumed. "When people loose teeth, they may eat fewer fruits and vegetables," Joshipura says. "And that, in turn, might affect their stroke risk. However, the results suggested that dietary factors evaluated did not seem to play an important role in the association between tooth loss and stroke found in this study."

She also suggested it is too early for physicians to try to apply the study's findings to patients. "I would be a little cautious," Joshipura says. "We need more studies before we can say that this is a causal association."

Six earlier studies had examined the association between stroke and periodontal disease and/or tooth loss but produced conflicting results. The Harvard researchers sought to resolve the relationship, in part by using a more uniform study population with more participants and by collecting data about whether the tooth loss and periodontal disease occurred before the stroke.

The challenge in determining cause and effect is to rule out the risk factors shared by periodontal disease, tooth loss, and ischemic stroke as alternative explanations.

"What is unique about this study is that we looked at a group of health professionals, who by nature are homogenous with respect to education, socioeconomic status and health behavior," she says. "They would be doing more things to keep themselves healthy, whether it is for their overall health, dental health or their cardiovascular health. So if we find an association in this kind of population, it is more likely that it is causal."

Co-authors are Hsin-Chia Hung, Dr.P.H.; Eric B. Rimm, Sc.D.; Walter C. Willett, M.D.; and Alberto Ascherio, M.D.

The study was funded by the National Institutes of Health.


Story Source:

The above story is based on materials provided by American Heart Association. Note: Materials may be edited for content and length.


Cite This Page:

American Heart Association. "Tooth Loss Linked To Increased Stroke Risk." ScienceDaily. ScienceDaily, 13 December 2002. <www.sciencedaily.com/releases/2002/12/021213062618.htm>.
American Heart Association. (2002, December 13). Tooth Loss Linked To Increased Stroke Risk. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2002/12/021213062618.htm
American Heart Association. "Tooth Loss Linked To Increased Stroke Risk." ScienceDaily. www.sciencedaily.com/releases/2002/12/021213062618.htm (accessed September 2, 2014).

Share This




More Health & Medicine News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Get on Your Bike! London Cycling Popularity Soars Despite Danger

Get on Your Bike! London Cycling Popularity Soars Despite Danger

AFP (Sep. 1, 2014) Wedged between buses, lorries and cars, cycling in London isn't for the faint hearted. Nevertheless the number of people choosing to bike in the British capital has doubled over the past 15 years. Duration: 02:27 Video provided by AFP
Powered by NewsLook.com
Can You Train Your Brain To Eat Healthy?

Can You Train Your Brain To Eat Healthy?

Newsy (Sep. 1, 2014) New research says if you condition yourself to eat healthy foods, eventually you'll crave them instead of junk food. Video provided by Newsy
Powered by NewsLook.com
We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Liberia Continues Fight Against Ebola

Liberia Continues Fight Against Ebola

AFP (Aug. 30, 2014) Authorities in Liberia try to stem the spread of the Ebola epidemic by raising awareness and setting up sanitation units for people to wash their hands. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins