News Release

More data needed to determine safety of probiotics and prebiotics

Peer-Reviewed Publication

American College of Physicians

Annals of Internal Medicine Tip Sheet

Below please find summaries of new articles that will be published in the next issue of Annals of Internal Medicine. The summaries are not intended to substitute for the full articles as a source of information.

1. More data needed to determine safety of probiotics and prebiotics

Trials of interventions aimed at modifying microbiota often neglect to report harms

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Randomized controlled trials (RCTs) assessing the efficacy of probiotics, prebiotics, and synbiotics often fail to report potential harms. Without safety data, experts warn that they cannot broadly conclude that these interventions are safe. The findings are published in Annals of Internal Medicine.

Interventions aimed at modifying microbiota are increasingly popular. Probiotics and prebiotics are becoming more common as an ingredient in foods and are promoted as helping to improve health, especially in the gastrointestinal tract. Despite promising results in clinical trials, questions remain about the safety of these interventions.

Researchers from the Centre of Research in Epidemiology and Statistics Sorbonne University and Columbia University studied 384 published RCTs assessing the safety or efficacy of at least one intervention involving probiotics, prebiotics, or synbiotics to examine how harms were reported. They found that harms reporting for these interventions were almost always missing, insufficient, or inadequate. One-third of the trials studied gave no information on harms, and only 2 percent adequately reported key safety components. According to the researchers, the inadequacy in reporting harms-related results may lead to an inaccurate safety profile and erroneous decision-making, with major consequences for patients.

Media contact: For an embargoed PDF, please contact Lauren Evans at To interview the lead author, Aida Bafeta, PhD, please contact her directly at

2. Physicians warn Zika still an important concern for female travellers

Women of reproductive age should discuss Zika prevention strategies with their doctor before planning a trip to Zika-affected countries

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Zika virus infection remains a risk to travelers who are pregnant or who may conceive in the near future. Women of reproductive age who are considering visiting Zika-affected countries should talk to their doctors about infection prevention strategies. An article discussing the current state of Zika virus is published in Annals of Internal Medicine.

The prevalence of Zika virus has decreased since its peak in 2016. However, according to infectious disease experts from Emory University School of Medicine, knowledge gaps about Zika virus transmission make the actual risk of infection for individual travelers difficult to predict. As such, the experts recommend that patients contemplating travel to Zika-affected areas should engage in shared decision-making with their care providers regarding travel plans and testing for Zika infection, and continue to take precautions against infection. In concurrence with recommendations from the Centers for Disease Control and Prevention (CDC), the experts advise pregnant women not to travel to Zika-affected areas. Returned travelers should take precautions against conception until 2 months for women and 6 months for men after travel or symptomatic infection.

The experts warn that one confounding aspect of Zika virus infection is that up to 80 of cases may be asymptomatic. New tests now under development and improved surveillance data may help travelers make more informed decisions in the future. For now, Zika remains an important concern for women of reproductive age.

Media contact: For an embargoed PDF, please contact Lauren Evans at To interview the lead author, Daniel S. Graciaa, MD, MPH, please contact Holly Korschun at

3. Hospitalists should promote mobility in the hospital to neutralize the toxicity of bedrest

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Promoting patient mobility in the hospital may help to neutralize the toxic effects of bedrest. Experts recommend ways in which hospitalists can take a leading role in preventing functional decline among older patients receiving acute care in the hospital. Their paper is published online in Annals of Internal Medicine.

A robust literature has demonstrated that bedrest leads to functional decline in hospitalized patients. In particular, those older than 65 years are at substantial risk, with approximately 1 in 3 having loss of independence in daily living after hospitalization. Hospitalists are in a unique position to take a leading role in promoting patient mobility. Hospitalists from the Perelman School of Medicine at the University of Pennsylvania outline ways in which hospitalists can promote healthy mobility during acute care.

The authors recommend that hospitalists first assess the patient's current level of mobility to establish a baseline and set goals. This information can be ascertained through speaking with the family and reviewing the patient's chart. Second, they say that hospitalists should formulate a mobility plan for each patient upon admission. The mobility plan should outline daily goals for time out of bed and walking. Finally, hospitalists should discuss the mobility plan with the bedside nurse and patient as an explicit part of the daily rounds to ensure that the plan is followed.

The authors believe that following a mobility plan could help to reduce the number of discharges to skilled nursing facilities, enhance patient engagement and experience, and perhaps even influence post-discharge outcomes.

Media contact: For an embargoed PDF, please contact Lauren Evans at To interview the lead author, S. Ryan Greysen, MD, MHS, please email him directly at and copy his assistant at


Also new in this issue:

Early Experiences With Journal Data Sharing Policies: A Survey of Published Clinical Trial Investigators
Sara Tannenbaum, BA; Joseph S. Ross, MD, MHS; Harlan M. Krumholz, MD, SM; Nihar R. Desai, MD, MPH; Jessica D. Ritchie, MPH; Richard Lehman, MA, BM BCh; Ginger M. Gamble, MPH; Jacqueline Bachand, MPH; Sara Schroter, PhD; Trish Groves, MBBS; Cary P. Gross, MD Letters: Observations: Brief Research Reports

Making the Voices of Female Trainees Heard
Lisa S. Rotenstein, MD, MBA; Rebecca A. Berman, MD; Joel T. Katz, MD; Maria A. Yialamas, MD
Ideas and Opinions

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