On Aug 7, 8:13=C2=A0am, Kofi <k...@[EMAIL PROTECTED]
> wrote:
> <http://www.sciencedaily.com/releases/2008/07/080715071419.htm>
>
> Science News
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> Stomach Bug Appears To Protect Kids From Asthma, Says New Study
> ScienceDaily (July 20, 2008) =E2=80=B9 A long-time microbial inhabitant
o=
f the
> human stomach may protect children from developing asthma, according to
> a new study among more than 7,000 subjects led by NYU Langone Medical
> Center researchers. Helicobacter pylori, a bacterium that has co-existed
> with humans for at least 50,000 years, may lead to peptic ulcers and
> stomach cancer. Yet, kids between the ages of 3 and 13 are nearly 59
> percent less likely to have asthma if they carry the bug, the
> researchers re****t.
>
> The study appears in the July 15, 2008, online issue of The Journal of
> Infectious Diseases.
>
> "Our findings suggest that absence of H. pylori may be one explanation
> for the increased risk of childhood asthma," says Yu Chen, Ph.D.,
> assistant professor of epidemiology at New York University School of
> Medicine and a co-author of the study. "Among teens and children ages 3
> to 19 years, carriers of H. pylori were 25 percent less likely to have
> asthma."
>
> The impact was even more potent among children ages 3 to 13: they were
> 59 percent less likely to have asthma if they carried the bacterium, the
> researchers re****t. H. pylori carriers in teens and children were also
> 40 percent less likely to have hay fever and associated allergies such
> as eczema or rash.
>
> These results, which follow on from similar findings in adults published
> by the same authors last year, are based on an analysis of data gathered
> from 7,412 participants in the fourth National Health and Nutrition
> Survey (NHANES IV) conducted from 1999 to 2000 by the National Center
> for Health Statistics.
> Dr. Chen collaborated on the survey with Martin J. Blaser, M.D., the
> Frederick H. King Professor of Internal Medicine, chair of the
> department of medicine, and professor of microbiology at NYU Langone
> Medical Center. Dr. Blaser has studied H. pylori for more than two
> decades.
>
> Asthma has been rising steadily for the past half-century. Meanwhile H.
> pylori, once nearly universal in humans, has been slowly disappearing
> from developed countries over the past century due to increased
> antibiotic use, which kills off the bacteria, and cleaner water and
> homes, explains Dr. Blaser. Data from NHANES IV showed that only 5.4
> percent of children born in the 1990s were positive for H. pylori, and
> that 11.3 percent of the participants under 10 had received an
> antibiotic in the month prior to the survey.
>
> The rise in asthma over the past decades, Dr. Blaser says, could stem
> from the fact that a stomach harboring H. pylori has a different
> immunological status from one lacking the bug. When H. pylori is
> present, the stomach is lined with immune cells called regulatory T
> cells that control the body's response to invaders. Without these cells,
> a child can be more sensitive to allergens.
> "Our hypothesis is that if you have Helicobacter you have a greater
> population of regulatory T-cells that are setting a higher threshold for
> sensitization," Dr. Blaser explains. "For example, if a child doesn't
> have Helicobacter and has contact with two or three cockroaches, he may
> get sensitized to them. But if Helicobacter is directing the immune
> response, then even if a child comes into contact with many cockroaches
> he may not get sensitized because his immune system is more tolerant."
>
> In other words, the presence of the bacteria in the stomach may
> influence how a child's immune system develops: if a child does not
> encounter Helicobacter early on, the immune system may not learn how to
> regulate a response to allergens. Therefore, the child may be more
> likely to mount the kinds of inflammatory responses that trigger asthma.
>
> "There's a growing body of data that says that early life use of
> antibiotics increases risk of asthma, and parents and doctors are using
> antibiotics like water," Dr. Blaser says. "The reality is that
> Helicobacter is disappearing extremely rapidly. In the NHANES IV study,
> less than six percent of U.S. children had Helicobacter, and probably
> two generations ago it was 70 percent. So, this is a huge change in
> human micro-ecology. The disappearance of an organism that's been in the
> stomach forever and is dominant is likely to have consequences. The
> consequences may be both good--less likelihood of gastric cancer and
> ulcers later in life--and bad: more asthma early in life."
>
> ------------------------------------------------------------------------
> Adapted from materials provided by NYU Langone Medical Center / New York
> University School of Medicine.
>
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Hi Kofi.
There are, however, potential dangers in H. Pylori
The two that I'm aware are peptic ulcer (that my wife suffered) and
gastric cancer: see below
=46rom the abstract of http://pmid.us/15106235
"REVIEWERS' CONCLUSIONS: Treatment of H. pylori infection is more
effective than antisecretory non-eradicating therapy (with or without
long-term maintenance antisecretory therapy) in preventing recurrent
bleeding from peptic ulcer. Consequently, all patients with peptic
ulcer bleeding should be tested for H. pylori infection, and
eradication therapy should be prescribed to H. pylori-positive
patients."
=46rom the free full text of http://pmid.us/17589938
"H PYLORI INFECTION AND GC [Gastric Cancer] RISK
Since the incidental discovery in 1983, the association of H pylori
with GC has become a hot topic of gastroenterological studies. Just a
decade later, a large cross-sectional study (the EUROGAST study)
involving 17 populations from 13 different countries (Unites States,
Japan and 11 European countries), concluded that H pylori-infected
patients had six-fold increased risk of GC compared with uninfected
subjects[72]. In 1994, despite some controversial opinion, the
International Agency for Research on Cancer declared H pylori to be a
group=E2=85=A0human carcinogen for gastric adenocarcinoma[73]. The
statemen=
t
was mainly based on epidemiological investigations since no
experimental studies had been performed at that time to prove the
causal link between H pylori and GC. Currently, although substantial
evidence sup****ts the role of H pylori infection in GC development,
the magnitude of the risk of GC associated with infection remains
unclear.
<big snip>
However, the most powerful evidence comes from a prospective study on
1526 Japanese patients followed for approximately 7.8 years. GC
developed in 36 out of 1246 H pylori-positive patients (2.9%) in
contrast to none of the 280 non-infected subjects[146]."
Fran=C3=A7ois Rose
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