Necrotizing enterocolitis (NEC), a swelling and bloating of the abdomen characterized by diarrhea, is a common cause of death among premature babies. It is caused by the tissue of the intestine dying off. But thankfully, new research shows that probiotics do indeed prevent this condition in infants, as well as late-onset sepsis (infection of tissue caused by bacteria) and other causes of death among low birthweight babies.
In a systematic review and meta-analysis of 44 previous papers on the topic, a study published in Neonatology showed that combinations of probiotics that include L. acidophilus and B. infantis are particularly effective. The study also showed that other strains of probiotics used alone are not effective.
The study distinguishes between extremely low birthweight infants (2 pounds, 3 ounces or less) and very low birthweight infants (3 pounds, 5 ounces or less).
“As the neonatology community moves forward today, it is necessary for the role of probiotics in extremely low birthweight infants to be defined,” wrote the authors, led by Elda Dermyshi, of the Departments of Gastroenterology, Hepatology and Nutrition, and Neonatology at Shanghai Children’s Hospital, Jiao Tong University, China. “We are living in the golden age of probiotics, but the question is whether or not we should use them in very low birthweight infants. The answer currently is that the debate is a very important one to have.”
The meta-analysis further concluded that the research does not support the single-strain use of probiotics L. reuteri, B. breve or S. boulardii.
“Despite the attractiveness of probiotics use in very low birthweight infants, proponents must understand that the counterarguments are very relevant,” Dermyshi et al. wrote. “The reasons not to use some types of probiotics and the difficulty in deriving dosage recommendations or probiotics combinations are as important for patients as the reasons in favor of using them. These doubts must never be ignored or discussed. Facing up to and seeking to resolve this debate is the only way to ensure that patients are the ultimate winners.”
There currently isn’t much clinical trial evidence available to safely determine whether giving probiotics to extremely low birthweight infants is worth the risks. “To address these investigative questions in preterm infants, especially in low birthweight infants, randomized controlled trials (RCTs) are not always easy or ethical to conduct,” per the paper. “Instead, well-designed observational studies may be the next practicable method to address these times of questions, as they have been shown to provide results similar to RCTs.”
In total, the 44 randomized and observational studies reviewed by the researchers included almost 23,000 patients. The authors found:
Twenty-nine randomized and fourteen observational studies on severe NEC showed “administration of probiotics significantly reduced the incidence of severe NEC.”
As for late-onset sepsis, 28 randomized trials showed probiotics reduced the rate of sepsis (pooled effect of all trials) by 12 percent. Among eight observational studies, probiotics reduced sepsis in very low birthweight infants by 19 percent.
Among randomized trials, 27 of them “significantly reduced the rate of mortality in the very low birthweight infants.” Eleven observational studies reached the same conclusion.
However, in extremely low birthweight infants, results were inconclusive.
“Even though our study included a larger number of RCT and observational studies, it did not reach the sample size needed to detect a statistically significant benefit for probiotic use in extremely low birthweight infants,” the authors wrote. “Therefore, the use of probiotics in extremely premature infants needs further investigation.”
In an unrelated study reported in The Guardian, a review of research regarding extremely low birthweight babies showed they are at greater risk of developing mental health and social problems later in life.