Navigation Links
Disappearing bacterium may protect against stroke

New York (January 9, 2013) -- A new study by NYU School of Medicine researchers reveals that an especially virulent strain of the gut bacterium Helicobacter pylori (H. pylori) isn't implicated in the overall death rate of the U.S. population, and may even protect against stroke and some cancers. The findings, based a nationwide health survey of nearly 10,000 individuals over a period of some 12 years, are published online, January 9, in the journal Gut.

Those individuals carrying the most virulent strain of H. pylori, the study found, had a 55 percent reduced risk of deaths from stroke compared with their counterparts who were not infected with H. pylori. Participants with the most virulent strain also had a 45 percent reduced risk of death from lung cancer.

These surprising findings emerged from an analysis by Yu Chen, PhD, MPH, associate professor of population health and environmental medicine, and Martin J. Blaser, MD, professor of internal medicine and professor of microbiology, of individuals who participated in a national survey designed to assess the health and nutritional status of adults and children in the United States. Previous studies by Dr. Blaser have confirmed the bacterium's link to gastric diseases ranging from gastritis to stomach cancer. He and Dr. Chen have more recently shown that H. pylori may protect against childhood asthma. The most virulent H. pylori strains have a gene called cagA.

"The significance of this study is that this is a prospective cohort of participants representative of the U.S. population with a long follow-up," says Dr. Chen. "We studied both the overall H. pylori as well as cagA strain of H. pylori, which is more interactive with the human body. We found that H. pylori is not related to the risk of death from all causes, despite it being related to increased risk of death from gastric cancer."

"This finding confirms earlier work, however, that gastric cancers are now uncommon in the United States," says Dr. Chen. "We also found that H. pylori was related to a reduced risk of stroke and lung cancer, and these effects were stronger for the cagA strain, suggesting its mixed role in human health," she says.

H. pylori, an ancient bacterium, lives in the mucous layer lining the stomach where, until recently, it survived for decades. More than half of the world's population harbor H. pylori in their upper gastrointestinal tract. Mainly transmitted in families, the bacterium is usually acquired before age 10. In developing countries H. pylori is still prevalent, but is vanishing in the developed world thanks to better sanitation and widespread use of antibiotics.

To better understand the relationship between H. pylori and the overall death rate, or all-cause mortality, the researchers analyzed data from 9,895 participants in the National Health and Nutrition Surveys (NHANES III), enrolled from 1988 to 1994. Test results for H. pylori and cagA were available on 7,384 subjects at the time of enrollment, and participants were followed until 2000.

There was no association of either H. pylori-positivity or cagA-positivity with all-cause mortality in the population, the researchers found. Participants with and without H. pylori experienced a similar risk of death from all causes. Consistent with past reports, a strong association was observed between H. pylori and gastric cancer mortality, according to the study. Individuals who were H. pylori positive were 40 times more likely to die from gastric cancer. The study also found that participants with cagA-positivity had a 55 percent reduced risk of deaths from stroke compared with their counterparts who were H. pylori negative/ cagA-negative. Participants with cagA-positivity also had a 45 percent reduced risk of deaths from lung cancer.

"The most interesting finding was that there is a strong inverse association with stroke which could be protective," says Dr. Blaser. "There is some precedent for this and it is possible that the same cells (T reg cells) that H. pylori induces that protect against childhood asthma could be the protective agents, however, the findings need to be confirmed."


Contact: Lorinda Klein
NYU Langone Medical Center / New York University School of Medicine

Related biology news :

1. Disappearing grasslands: ASU scientists to study dramatic environmental change
2. Scientists reveal how natural antibiotic kills tuberculosis bacterium
3. Bacterium signals plant to open up and let friends in
4. Virginia Tech and University of Tuscia lead team to unravel origin of devastating kiwifruit bacterium
5. Romper suit to protect against sudden infant death
6. Native orchid protection and conservation subject of new AgriLife Research study
7. UC Irvine study of leaping toads reveals muscle-protecting mechanism
8. Arming US troops with insect-protective gear
9. Double duty: Immune system regulator found to protect brain from effects of stroke
10. Better protection for forging dies
11. Ah, that new car smell: NASA technology protects spacecraft from outgassed molecular contaminants
Post Your Comments:
(Date:6/20/2016)... , June 20, 2016 Securus Technologies, ... technology solutions for public safety, investigation, corrections and ... prisons involved, it has secured the final acceptance ... facilities for Managed Access Systems (MAS) installed. Furthermore, ... facilities to be installed by October, 2016. MAS ...
(Date:6/9/2016)... 9, 2016 Paris Police ... video security solution to ensure the safety of people and ... during the major tournament Teleste, an international technology ... services, announced today that its video security solution will be ... back up public safety across the country. The system roll-out ...
(Date:6/2/2016)... NEW YORK , June 2, 2016   The ... (Weather), is announcing Watson Ads, an industry-first capability in which ... advertising, by being able to ask questions via voice or ... Marketers have long ... with the consumer, that can be personal, relevant and valuable; ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... /PRNewswire/ - FACIT has announced the creation of ... company, Propellon Therapeutics Inc. ("Propellon" or "the Company"), ... portfolio of first-in-class WDR5 inhibitors for the treatment ... represent an exciting class of therapies, possessing the ... cancer patients. Substantial advances have been achieved with ...
(Date:6/23/2016)... 2016 Houston Methodist Willowbrook Hospital has ... Association to serve as their official health care ... Willowbrook will provide sponsorship support, athletic training services, ... coaches, volunteers, athletes and families. "We ... Association and to bring Houston Methodist quality services ...
(Date:6/23/2016)... Prostate Cancer Foundation (PCF) is pleased to announce 24 new Young ... cancer. Members of the Class of 2016 were selected from a pool of ... More About the Class of 2016 PCF Young Investigators ... ... ...
(Date:6/23/2016)... , June 23, 2016   EpiBiome , ... secured $1 million in debt financing from Silicon Valley ... up automation and to advance its drug development efforts, ... new facility. "SVB has been an incredible ... the services a traditional bank would provide," said Dr. ...
Breaking Biology Technology: