This news release focuses on a recent study that found new biomarkers in the sweat of infants that are associated with cystic fibrosis (CF). The news release does a good job of explaining how these biomarkers may be valuable in helping to diagnose borderline cases of CF, in which conventional diagnostic techniques leave some uncertainty about whether an infant has the disease. However, in spite of speculation and a suggestive headline, there is little explanation of how the new findings could possibly affect treatment for CF patients — which is a significant oversight, given that the headline focuses on CF treatment, not diagnosis.
Cystic fibrosis is a genetic disorder that affects a relatively small number of people each year. But those with the disease face a lifetime of extensive medical treatments to address the disease and its symptoms. CF is not curable. Life expectancy for those with the disease in the U.S. is now approximately 37 years, up from a median survival age of only 10 years in 1962. That improvement is due to significant advances in treatment, which cannot begin until the condition is diagnosed. Ergo, diagnosis is crucial. That would appear to be the biggest advantage we can clearly define from the new study. While it is possible that the study’s finding may also contribute to new advances in CF treatment, that is currently only conjecture. Anyone expecting details of new advances in treatment based on the headline of this news release is sure to be disappointed.
The study does not address costs. The method used to identify the new biomarkers is described as “a specialized technique developed at McMaster [University]” (where the research was done), making it difficult or impossible to estimate what the cost may be.
The benefit here would appear to be that diagnostic testing for CF would be better able to identify infants who have CF, and possibly understand more about the expected course for individual patients — particularly patients with borderline results on the sweat chloride test currently used to diagnose CF in newborns. However, it’s not clear how common these cases are. Are there a lot of patients who have borderline sweat chloride tests?
In addition, the release doesn’t tell us how much better the new biomarkers are at diagnosing CF. It suggests that the new tests add accuracy to the diagnosis — but by how much?
The potential harms here involve errors in diagnosis. More specifically, the story does not address the specificity or sensitivity of the biomarker testing. And this is important. Specificity indicates how good a test is at ruling out people who don’t have a problem. Sensitivity addresses how good a test is at positively identifying people who actually have the problem. False positives can result in unnecessary treatments and costs. False negatives can result in patients not getting treatments that could help them. And if it’s still too early to tell what the specificity or sensitivity of the tests are, they need to address that.
The release does not tell readers how many patients were involved in the study, making it impossible to tell how robust these findings are. In this case, the relevant journal article tells us that there were 50 infants who were not affected by CF and 18 that were affected by CF. For most conditions, this would be considered a very small sample size. It’s not clear whether consideration needs to be given to the fact that CF is a relatively uncommon disorder, making it more difficult to garner a larger sample size. The release would have been stronger if it had addressed this.
No disease mongering here.
The funding source is clearly marked and there does not appear to be a conflict of interest. However, it’s not clear whether the “specialized technique developed at McMaster” is being patented for use in the marketplace, or if it is being made freely available to other researchers. Either way, that would be a valuable point to make in the release.
The release does a good job of explaining the sweat chloride test, which is widely used to make a final diagnosis of CF in infants and children.
It is not clear how far these research findings are from making their way into clinical use.
The story does a good job of explaining what is new here — researchers have found specific chemicals in the sweat of infants with CF that appear to be related to the disease. The release only stumbles when presenting what these findings mean or how they may be used in the context of clinical diagnosis and care.
Here’s the news release headline: “Scientists discover biomarkers which could lead to better treatments for CF patients” (emphasis added). Treatments are mentioned only twice in the text of the release. Here, in the second paragraph: “The findings…shed new light on the underlying mechanisms of CF and could lead to improved prognosis and better therapies for a disease which is quite variable, affecting different children in different ways, say researchers.” And here, in the ninth paragraph: “The biomarkers also point to other underlying mechanisms that contribute to the progression of CF and could lead to better therapeutic interventions earlier in life.” In short, the release offers very little to support the idea of better treatments for CF patients. How does the study improve our understanding of the underlying mechanisms of CF? And how could that potentially lead to improved treatments? The release doesn’t tell us. One could see how it may lead to earlier treatment, if diagnoses are improved, but the release doesn’t address how earlier treatment could improve patient outcomes. So, while one can say that these biomarkers “could” lead to better treatments, one could just as easily say that these biomarkers “may not” lead to better treatments. The release would have been on much firmer ground if it had either fleshed out how the findings may inform future treatment research or had focused on the value of the study’s findings in regard to diagnostics.