The Trial
August 29, 2007
Infections are pretty common in young children, and so is use of antibiotic treatment. But this rite of passage often has unpleasant consequences − about one-third of kids will develop diarrhea because either the infection or its treatment upsets their bodies’ normal balance of intestinal bacteria. Now, researchers at Georgetown University Medical Center are, for the first time, set to test whether one of the world’s oldest “health” drinks can produce a better outcome in children being treated for an infection.

This month, researchers in the Department of Family Medicine began a clinical trial to study whether use of kefir, a drink rich in “probiotics,” can prevent diarrhea in children who have been prescribed a ten-day course of antibiotics. Probiotics are live bacteria, which given in sufficient amounts, may improve health, says the study’s lead investigator, Daniel J. Merenstein, M.D., director of the Department of Family Medicine. Probiotics are found in supplemental forms or in foods such as yogurt, kombucha tea, sauerkraut and kefir.

“ Kefir, which originated in Eurasia, has been used for hundreds of years to promote health, and has much promise as a preventive food that may help treat certain conditions,” Merenstein says. “We are interested in putting such potential benefits under the microscope, so to speak, by examining it through clinical trials.”

Kefir is a milk product produced by the action of ten probiotics, which is “five times the amount that most yogurts contain,” he says. Some probiotics have been shown to keep the stomach and immune system strong and stable, especially when disturbed by antibiotics. Studies have examined the potential health beefits of other probiotics in the prevention and treatment of both antibiotic and infectious diarrhea, Merenstein says. “The probiotics have generally been given as supplements or pills, but we want to test the effects of supplying these probiotics in food products that are more readily available.”

Their MILK Study will enroll 130 children, 1-5 years of age, who will be randomized into two groups. One group will drink 5 ounces of kefir with their antibiotic tablet each day and the other group will be given a similar-tasting placebo drink. According to research associate Haewon Park, M.P.H., investigators will look to see if there is a statistically significant reduction of 10 percent or more in occurrence of diarrhea in patients drinking kefir, compared to participants who consumed the placebo drink.

The study is being funded by Lifeway Foods, which manufacturers Probug’s Organic Whole Milk Kefir™, but Georgetown University owns all of the data that results from the study and has full publication rights, Merenstein says.

“The current treatment for diarrhea in young children is oral rehydration products and while they do rehydrate youngsters, they play no role in the prevention of diarrhea,” Merenstein says.

Results
August 3, 2009
Kefir, one of the world’s oldest “health” drinks, did little to prevent diarrhea in young children being treated with antibiotics, say researchers at Georgetown University Medical Center (GUMC), who tested the drink in a unique and rigorous double-blind clinical trial.

While the study results, published in the August issue of Archives of Pediatrics and Adolescent Medicine, are negative, investigators say there are intriguing hints that the drink, which is rich in probiotics – live bacteria - appeared to help the children in the study who were the least healthy.

“We were initially interested in this study because many physicians are already recommending yogurts, kefirs, and probiotics supplements to prevent diarrhea associated with use of antibiotics,” says the study’s lead author, Daniel J. Merenstein, MD, director of research in the Department of Family Medicine at GUMC.

A number of studies have shown that probiotics can help prevent and treat diarrhea, even in people using antibiotics but this has often been shown in very different settings than is typical in the United States, Merenstein says. Children are especially susceptible to this problem, he says - about 20-30 percent of kids using antibiotics will develop diarrhea from the antibiotic, and this often results in them stopping the antibiotic or additional doctor visits. Many of these previous studies, however, were not “double-blinded” – that is, compared with a placebo drink that resembled kefir.

“This study didn’t prove the benefit of kefir in these children– not all probiotics work the same - but the results also suggest that kefir may work best in younger, sicker children,” Merenstein says. “More studies with this particular group of children are warranted.”

Kefir, which originated in Europe and Asia and has been used for hundreds of years, is a milk drink. The kefir Merenstein studied was fermented by ten probiotics. It is believed to keep the stomach and immune system strong and stable.

Previous studies lacked the rigor needed to be conclusive, so Merenstein designed a clinical trial in which 125 children, ages 1-5, being treated for antibiotics, were given either a kefir drink to use with their antibiotic tablet each day for ten days or a kefir drink in which the probiotics were previously destroyed by heat (placebo). Neither the study coordinators, the children, nor their parents knew which drink was given to which participant until the study ended. “This double-blind trial design is the gold standard for a clinical trial,” Merenstein says. “It is the best way to determine if an agent or substance being studied provides benefit.”

The study was designed by Merenstein and funded by Lifeway Foods, which manufacturers Probug’s Organic Whole Milk Kefir™, but Georgetown University owns the data that results from the study and has had full publication rights, Merenstein says.

Researchers found that 18 percent of children in the kefir group developed diarrhea compared to 22 percent in the placebo group – which is not a statistically significant difference. However, in the children whose health was poorer at enrollment, 23 percent developed diarrhea in the kefir group, compared with 31 percent in the placebo group.

“Our theory is that kefir may not have helped healthy children that much because the extra immune system boost provided by the drink may not be necessary,” Merenstein says. “It is possible looking at our data that Probug’s kefir may have some benefit in specific groups. We have found with our other studies that in very healthy children the benefit of probiotics may be minute and difficult to elicit in small studies. That is why we need new larger studies in children to elicit who might benefit.”

About Georgetown University Medical Center
Georgetown University Medical Center is an internationally recognized academic medical center with a three-part mission of research, teaching and patient care (through our partnership with MedStar Health). Our mission is carried out with a strong emphasis on public service and a dedication to the Catholic, Jesuit principle of cura personalis -- or "care of the whole person." The Medical Center includes the School of Medicine and the School of Nursing and Health Studies, both nationally ranked, the world-renowned Lombardi Comprehensive Cancer Center and the Biomedical Graduate Research Organization (BGRO), home to 60 percent of the university’s sponsored research funding.