OT:McGill researchers say some antacids raise risk of bacterial infection Canadian Press

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McGill researchers say some antacids raise risk of bacterial infection

Canadian Press

TORONTO — Researchers at McGill University say re-analysis of data from

a large British database supports their controversial argument that

widely prescribed antacid drugs may be predisposing some users to

develop C. difficile, a nasty and recurrent diarrhea that sometimes

proves fatal, outside of hospital settings.

Led by Dr. Dial, the study suggests people who were taking the

drugs — called proton pump inhibitors — were three and a half times

more likely to develop Clostridium difficile-associated disease than

non-hospitalized people who didn't take the popular medications. The

study was published Monday by the Canadian Medical Association Journal.

Evidence on the idea has been conflicting, with some teams finding a

link and others discounting it. More studies will likely emerge in the

next few weeks as infectious disease researchers converge on two major

conferences for their field, one in San Francisco later this week and

one in Toronto in mid-October.

If Dr. Dial's work proves to be true, it would suggest research on C.

difficile has been focused too narrowly to date, looking mainly at the

incidence and causes of cases found in hospitals.

“The more I've looked into Clostridium difficile, I think there's a

whole lot more we need to learn about this disease,” Dr. Dial said from

Montreal.

Concern over the increasing incidence and severity of C. difficile hit

the scientific community's radar several years ago. In the flurry of

research papers that has followed, the nasty and recurrent diarrhea has

been largely described as a hospital-based problem, where rampant

antibiotic use has made patients vulnerable to the sometimes fatal

bacterium.

But Dr. Dial and others are suggesting antibiotics alone can't account

for the entire increase, particularly in C. difficile infections in

people who haven't recently been hospitalized.

“It's almost like they got an unfair head start in the blame game,”

Dial said.

“They definitely play an important role. But the message we'd maybe

like to get out is: If your patient in the community hasn't gotten an

antibiotic but they're having diarrhea, and if they're elderly and

they're sick and have some of the other things (risks) we've found,

consider checking them for C. diff.

“Don't just assume they don't have it because they didn't get an

antibiotic.”

Proton pump inhibitors are used to treat acid reflux and peptic ulcers

and to prevent peptic ulcers in people taking daily doses of Aspirin or

other painkillers which are hard on the stomach. Popular brands include

Nexium, Losec and Pariet.

Dr. Dial and several of the same co-authors suggested the drugs might

be playing a role in C. difficile disease in an article published last

December in the Journal of the American Medical Association. Their

argument, based on analysis of cases from this same British database,

met with skepticism in some quarters, in part because of the way their

study was designed.

In an effort to make the argument more airtight, they went back to the

database, focusing only on people who received an oral form of the

antibiotic vancomycin. As the only accepted use for the expensive drug

is to treat C. difficile, anyone who was prescribed the drug probably

had the disease, they argued.

But some experts not involved in the study, including a field leader,

Dr. Dale Gerding, acknowledge being “a little skeptical about the study

design.”

Dr. Gerding, a researcher at Hines Veterans Affairs Hospital in

Chicago, said it would be useful to test the PPI theory in the animal

model used to study the disease, hamsters.

It's important to find out if the drugs are playing a role in

development of C. difficile, agreed Dr. Clifford Mc, a C.

difficile expert at the U.S. Centers for Disease Control.

“The issue of the PPIs is a big one because they are used so much,”

Dr. Mc said from Atlanta.

As the study of C. difficile has expanded, it's becoming apparent what

happens in hospitals is only part of the story, he suggested, noting

there is other emerging evidence to support the idea PPIs may be

playing a role.

“I think we can say the fact that people can have C. diff without

antibiotic exposure is becoming more clear,” Mc said.

“Whether that's a new phenomenon or people are testing more, we don't

know.”

Gerding suggested if PPIs are linked to a rise in C. difficile cases,

it may be because proton pump inhibitors have a mild antibiotic affect

— not because, as others argue, they lower the acidity of the stomach

and make it easier for C. difficile spores to survive and thrive.

To boost his argument, he noted that Dial's study found that people

taking another type of antacid drug were not at greater risk of

developing C. difficile.

“So it may not have anything to do with the anti-acid effect of the

drug but rather something else about it,” Dr. Gerding suggested.

Dr. Simor, an infectious disease specialist at Toronto's

Sunnybrook Health Sciences Centre, said while he's open to the argument

Dr. Dial is making, the jury is still out on whether PPIs are fostering

an increase in C. difficile cases.

But he agreed that something more is at play than over-use of

antibiotics.

“This disease occurred before antibiotics. So while in today's

environment there is little doubt antibiotics are the major player,

they are obviously not the only one. And there has to be multiple risk

factors involved in many of these patients.”

Carol F.

Celiac, MCS, Latex Allergy, EMS

SCD 6 years