Harold J. DeMonaco is the Assistant Chief Medical Officer for Care Transitions at the Massachusetts General Hospital and a long-time contributor to HealthNewsReview.org.
It is always interesting to see how the results of a well-designed and important study can get distorted as they flow through the media. The recent publication of Development and Validation of a Biomarker for Diarrhea-Predominant Irritable Bowel Syndrome in Human Subjects in PLOS Medicine is a great example.
Bowel disorders, especially those associated with unpredictable diarrheal symptoms, are no picnic. They are especially cumbersome when they turn from an acute episode to a chronic condition. So, it is not surprising that a “simple test” for diagnosing diarrhea-dominant irritable bowel syndrome (D-IBS) would be something the media would pay attention to. The study conclusions in this peer reviewed journal are as follows:
“In conclusion, this study validates the presence of anti-vinculin and anti-CdtB as blood based biomarkers that separate D-IBS from IBD and healthy controls using a large scale prospective multicenter trial. Anti-vinculin and anti-CdtB antibodies also appear part of the pathophysiology of post-infectious IBS and may identify a subgroup of D-IBS for directed therapies. Most importantly, this appears to be an important step in determining organic bases for IBS.”
Notice the careful language in the summary. The biomarkers, “…may identify a subgroup of D-IBS for directed therapies.” Now take a look at the news release from Cedars Sinai, the institution that holds the patent on the test.
The news release then goes on to note,
“Pimentel and fellow researchers studied nearly 3,000 people, comparing IBS patients to those diagnosed with inflammatory bowel disease, celiac disease and those with no GI disease. The blood tests identified the two antibodies associated with IBS — anti-Cdtb and anti-vinculin — with greater than 90 percent certainty.”
As we noted in our systematic review of this news release, the text carefully ignores many of the caveats and limitations discussed in the study itself, including the fact that the biomarkers are considerably less efficient at discerning celiac disease from D-IBS.
Our review of a CBS News story that was likely prompted by this release reflects many of the same problems, starting with the headline:
At the end of what is close to an advertisement for the lab tests, we finally get some measure of clarity:
“CBS News chief medical correspondent Dr. Jon LaPook, who is also a practicing internist and gastroenterologist, points out that the test is not perfect. While a positive test result is highly suggestive of IBS, only 44 percent of patients with IBS tested positive, meaning that many people who test negative could in fact still have the condition.”
Perhaps I should not be surprised. After years of reviewing how the media reports on medical issues for HealthNewsReview.org, I have come to expect this kind of coverage. Wildly inflated headlines designed to grab your attention, incomplete reviews of the research, and then — if you are lucky — a brief clarifying statement at the very end of the story.
I think we can do better than this. And with HealthNewsReview.org’s new funding and capabilities, we are now in a position to patrol the health news stream along its winding course like never before. We can point out where the stream is getting polluted and identify opportunities to clean it up.
Ultimately, the goal is a better, more informative health news product for the millions who drink from these waters.