Note to our followers: Our nearly 13-year run of daily publication of new content on HealthNewsReview.org came to a close at the end of 2018. Publisher Gary Schwitzer and other contributors may post new articles periodically. But all of the 6,000+ articles we have published contain lessons to help you improve your critical thinking about health care interventions. And those will be still be alive on the site for a couple of years.
Read Original Story

HealthDay carefully describes link between breastfeeding and preemie eye disease

baby face

Breast-feeding a premature infant may help reduce the risk of a serious eye problem known as retinopathy of prematurity (ROP), new research suggests.

The researchers said that when babies were exclusively fed breast milk, the risk of any-stage ROP appeared to drop by about 75 percent. And the risk of severe ROP seemed to be reduced by 90 percent, the researchers added.

“Human milk feeding potentially plays a strong role in protecting very preterm newborns from any-stage ROP and severe ROP,” the international team of study authors wrote.

Retinopathy of prematurity causes blood vessels to grow in the retina, the light-sensitive tissue in the back of the eye. When the vessels grow, they can cause the retina to detach, destroying vision, according to the U.S. National Eye Institute.

For the study, researchers from China, Canada and the United Kingdom reanalyzed the results of five published studies on ROP. The studies included more than 2,200 preterm infants, comparing how often babies had been fed human milk or formula, and whether or not they developed ROP.

However, the new analysis only showed an association between breast milk and a reduced risk of ROP. It did not prove a cause-and-effect relationship due to the study’s design.

Results of the study were published online Nov. 16 in Pediatrics.

Extremely preterm babies are most at risk of ROP. In the United States, 59 percent of babies born at 22 to 28 weeks have the disorder, said study researcher Dr. Chao Chen, a neonatologist at Children’s Hospital of Fudan University, in Shanghai. He added that in China, a previous study showed the incidence of ROP was 50 percent in infants with a birth weight under 1,000 grams (2.2 pounds).

ROP “has become a leading cause of childhood blindness in recent time,” Chen said. “In general, there are more ROP cases in developed countries, but more severe cases and higher rates of blindness in developing countries.”

The greater incidence of ROP is likely due to the increasing survival rate of very preterm babies in developed countries, according to Chen. In developing countries, preterm babies are less likely to survive. When they do, the screening and treatments are not as good, Chen said, so blindness may be more likely.

Babies in the studies had a range of gestational ages, from 26 to about 30 weeks. Their weights ranged from about 1.7 pounds to about 3 pounds. No information was given about how long the breast-feeding continued.

In re-evaluating the studies, Chen’s team found that breast-feeding in any amount appeared to reduce the risk of ROP. And it appeared that the more breast milk, the better. Exclusive breast-feeding seemed to drop the odds of ROP by 75 percent compared to exclusive formula use. And any breast-feeding appeared to reduce the odds of the serious eye disease by 46 percent, the research showed.

How might human milk offer protection from the eye disorder? The antioxidants in human milk may help, Chen said. Human milk also has immune-protective properties, the researchers said. Breast-feeding also seems to help prevent two conditions known as sepsis and necrotizing enterocolitis that may require oxygen therapy, which has also been linked to a higher risk of ROP, the study authors said.

Dr. Adolfo Llanos, a neonatologist at Nicklaus Children’s Hospital in Miami, who was not involved with the new study, said the “quality of this analysis is very good. It’s reassuring to see the benefit we see with breast milk.”

He said breast milk may help by reducing inflammation in the body. “Preemies don’t regulate inflammation in their bodies well,” he said.

Llanos cautioned that the study looked only at a mother’s own breast milk, not donor milk, which can be used when the biological mother doesn’t have enough of her own breast milk.

The takeaway from this study, Llanos said, is to breast-feed as long as possible, if possible.

More information

To learn more about breast-feeding, visit American Academy of Pediatrics.

SOURCES: Chao Chen, M.D., Ph.D., neonatologist, Children’s Hospital of Fudan University, Shanghai, China; Adolfo Llanos, M.D., neonatologist, Nicklaus Children’s Hospital, Miami, Fla.; December 2015, Pediatrics

Last Updated: Nov 16, 2015

Rating

5 Star

Breast-Feeding Linked to Reduced Risk of Preemie Eye Problem

Our Review Summary

Mother holding baby boy

This article consists overall of balanced reporting. There are a few missteps in presenting the quantitative evidence but some very strong points are present as well, including the acknowledgement that the studies under consideration are all observational in nature, and the corresponding reminder that “correlation does not imply causation.”

 

Why This Matters

Retinopathy of prematurity (ROP) is a potentially blinding eye disorder. The article reports on a meta-analysis examining whether human breast milk, compared with formula, is associated with protection against developing ROP.

Criteria

Does the story adequately discuss the costs of the intervention?

Not Applicable

Cost is not a relevant criterion in this case as the comparison is made between breast milk and formula. Both feeding methods entail costs, both financial and other, that we feel are beyond the scope of the coverage.

Does the story adequately quantify the benefits of the treatment/test/product/procedure?

Not Satisfactory

There are a couple of improvements we recommend here. First, we wish that the drop in odds of ROP had been reported more precisely, as there are many different combinations of variables being compared in the study. To start, the disease ROP is separated into 1) any-stage and 2) severe. (These terms are used here and there in the article but not defined.) For each level of ROP, the study makes the following comparisons:

  1. exclusive human milk versus any formula
  2. mainly human milk versus mainly formula
  3. any human milk versus exclusive formula
  4. exclusive human milk versus exclusive formula

Out of the four comparisons, the drop in odds of ROP (any-stage or severe) of breast milk versus formula is the most eye-catching in the fourth comparison. This also happens to be the comparison reported in the second paragraph of the article. While we do not wish to presume this comparison was cherry-picked, we feel that if word count had been a factor in limiting the reporting of only one comparison above, the second comparison is the one that should have been reported. This is because the sample size is largest for the second comparison, giving more credence (or as statisticians might say, more power) to the numbers.

More precision is also warranted regarding the specific comparison being made. The statistics cited in the second paragraph fail to mention that the comparison is between exclusive human milk and exclusive formula. Later in the article, two more statistics, a 75% drop and 46% drop in the odds of ROP, are cited. Here, it would’ve been good to qualify the statistic by stating that these numbers relate to drops in any-stage ROP. Moreover, these are relative risk comparisons, and so it’s unclear if these impressive-sounding drops in risk translate to large absolute numbers. The story could have clarified that.

Does the story adequately explain/quantify the harms of the intervention?

Not Applicable

In the framework of our criteria, the intervention in this study is the feeding of human milk. The potential harms of human milk do not seem to warrant a discussion in this article however.

Does the story seem to grasp the quality of the evidence?

Satisfactory

Sometimes statisticians sound like broken records with their “correlation is not causation” warnings. The article is one step ahead in this case. We find the following sentences that would make every statistician proud:

However, the new analysis only showed an association between breast milk and a reduced risk of ROP. It did not prove a cause-and-effect relationship due to the study’s design.

Also, the article shows a good grasp of the evidence quality by reporting some of the limitations of the study, including the limitation that the study looked only at a mother’s own breast milk, not donor milk.

The story safely clears our bar here, but it could have done even better to avoid phrases such as this one: “Breast-feeding a premature infant may help reduce the risk of a serious eye problem known as retinopathy of prematurity.” The active verb “help reduce” suggests a cause-and-effect relationship that, as the story tells us, is not appropriate to imply with a study such as this one.

Does the story commit disease-mongering?

Satisfactory

We paused to take a second look at the statement that ROP “has become a leading cause of childhood blindness in recent time.”

That sounds scary, but the story qualifies things nicely when it notes, “The greater incidence of ROP is likely due to the increasing survival rate of very preterm babies in developed countries.” That’s good context because it explains that the condition is actually a consequence of a positive trend in health care.

Does the story use independent sources and identify conflicts of interest?

Satisfactory

Thumbs up here for interviewing an independent source, Dr. Adolfo Llanos. Although, we question the choice to end the article with the following quote from Dr. Llanos

The takeaway from this study, Llanos said, is to breast-feed as long as possible, if possible.

That’s slightly puzzling, since the stated conclusion in the original study is much more tentative

Based on current limited evidence, in very preterm newborns, human milk feeding potentially plays a protective role in preventing any-stage ROP and severe ROP.

The story would have probably done better to omit this source’s simplistic conclusion.

Does the story compare the new approach with existing alternatives?

Not Applicable

The article does not mention other preventative measures to take against ROP besides breast milk and formula. But neither does the original study, so we’ll leave this criterion as not applicable.

Does the story establish the availability of the treatment/test/product/procedure?

Not Applicable

We won’t dock points from the story for not discussing the availability of formula and breast milk. Although those topics could certainly sustain such a discussion had the story chosen to address them.

Does the story establish the true novelty of the approach?

Satisfactory

The article clearly identifies the underlying study being based on a reanalysis of five previously published studies on ROP (or what is known in the lingo as a meta-analysis). The article might have indicated that this is one of the first such meta-analyses done on ROP.

Does the story appear to rely solely or largely on a news release?

Satisfactory

We can be fairly confident that the article did not rely solely on a news release, especially since it has an independent source.

Total Score: 5 of 6 Satisfactory

Comments

Please note, comments are no longer published through this website. All previously made comments are still archived and available for viewing through select posts.