NATIONAL HARBOR, MD. – Prophylactic use of probiotics appears to reduce the odds of developing antibiotic- associated diarrhea by 60%, based on data from a meta-analysis of more than 3,000 patients. The findings were presented at the annual meeting of the American College of Gastroenterology.

The incidence and severity of antibiotic-associated diarrhea (AAD) are increasing in the United States, with major financial and clinical implications, said Dr. Steven Shamah of Maimonides Medical Center in Brooklyn, N.Y.

“Given the enormous cost, morbidity, and mortality associated with this [disorder], it is important to identify those at-risk populations and institute preventative measures,” Dr. Shamah said. The most common type of AAD is Clostridium difficile–associated diarrhea (CDAD).

Several studies have examined the effectiveness of daily treatment with probiotics to prevent AAD, but results have been mixed, he noted. Dr. Shamah and colleagues reviewed data from 22 studies including 3,096 patients, 63% of whom were adults. A total of 53% of the study subjects were from outpatient settings and 47% were hospitalized patients.

The researchers conducted a chi-square analysis of patients who had successful and failed probiotic treatments. Overall, patients who took probiotics had significantly reduced odds of developing AAD (odds ratio, 0.39). The probiotic treatment periods ranged from 5 days to 3 weeks, with an average treatment duration of 1.5 weeks, Dr. Shamah said.

“This analysis clearly demonstrates that probiotics offer protective benefit in the prevention of [AAD],” said Dr. Shamah.

All patients who are at high risk for AAD should receive probiotic prophylaxis, he added. Risk factors for AAD include recent antibiotics use, old age, recent hospitalization, low albumin, and immunosuppression.

However, additional prospective studies are needed to determine the most effective dose, duration, and specific species of probiotics to prevent AAD and CDAD in these patients, he noted. Dr. Shamah said he had no financial conflict to disclose.


Heidi Splete is a senior writer with Elsevier Global Medical News.