Critical Thinking: When to be Skeptical (Part 2)

Last time I wrote about a case where ill-advised skepticism leads to dangerous decisions, what the World Health Organization calls “vaccination hesitancy,” one of the ten threats to global health. About 1.5 million deaths per year could be avoided if global coverage of vaccinations improved.

In the case of vaccines, that skepticism is based on faulty evidence and discredited research promoted by unreliable sources. But in many other cases, with access to reliable sources, it makes sense to be a little skeptical of all the threats and warnings we encounter on a daily basis. After all, no one has enough time to be scared of everything the media warns us about.

Sometimes it’s a health issue where the underlying data is insignificant, e.g., when a certain habit is shown to increase the chance of getting a condition by 50%, when the original chance of getting it was miniscule. Sometimes organizations raising money and the media selling advertising space don’t present the full story. For example, data from the early 2000s on missing children shows that 99.8% of those children return home. “Only about 100 children (a fraction of 1% [of all missing children]) are kidnapped each year in the stereotypical stranger abductions you hear about in the news.” More die in swimming pool accidents, yet “stranger danger” gets much more attention than pool safety. It is very likely that the data have not changed since that original study.

Things are not always as they seem. Here is one example I intend to keep an eye on. At sciencemag.org a feature titled “Dubious Diagnosis” asks, “The war on ‘prediabetes’ could be a boon for pharma—but is it good medicine?”

The piece points out that the term prediabetes originated only about ten years ago as a “public relations catchphrase” to raise awareness at a time when the American Diabetes Association (ADA) “needed a pitch to persuade complacent doctors and the public to take seriously a slight elevation in blood glucose, which might signal a heightened risk of type 2 diabetes.” Indeed it has a catchier sound than impaired fasting glucose or impaired glucose tolerance. And notice the expression might signal in the explanation. Further along, the article tells, “the CDC's own data show progression from prediabetes to diabetes at less than 2% per year, or less than 10% in 5 years. (Other studies show even slower rates.)”

This increased public awareness probably benefited the ADA, but other health-oriented organizations such as the World Health Organization (WHO) along with some diabetes specialists argue “medical and epidemiological data give weak support, at most, for increasingly dire prediabetes admonitions.” One diabetes researcher goes so far as to characterize the effort as scaremongering directed at approximately 48 million Americans.

The result is that billions of dollars have been spent on “research, education, and health improvement programs – generally focused on weight loss and exercise – that have generated lackluster results, according to critics.” So far no drugs are effective, but some of those research dollars include “drug companies…testing dozens of drugs aimed at prediabetes in hopes of tapping a potential worldwide market of hundreds of millions of people.”

And the rising costs are already compounded by additional doctor visits, off label prescriptions, and the sale of continuous glucose monitor devices – all very likely unnecessary.

Meanwhile, the ADA continues to ratchet down the standards for various blood sugar measurements with the potential of adding another 72 million new patients to the prediabetes rolls in the United States and many more worldwide.

The article includes several interesting timelines showing changes in those standards and other key events. It then discusses at length the scientific and financial conflicts. So despite some very confident statements favoring prediabetes screening and treatment, the jury is still out. “Many public health organizations believe a mainly clinical approach to diabetes prevention [endorsed by the ADA and CDC] is ineffective.”

There seems to be plenty of reason to remain skeptical about this issue. (It does not affect me, but I find it very interesting from a critical thinking point of view.)