Thursday, April 13, 2006

Disease Mongering and the Calibration of Skepticism

The Public Library of Medicine has a collection of essays on the topic of  disease mongering.  The essays were written in conjunction with an international conference on the topic.  There has been a little bit of publicity on the topic; such as these news articles:
Drug firms 'hype up diseases to boost sales'
By RICHARD SHEARS, Daily Mail 08:35am 11th April 2006

Drug companies are inventing diseases to sell more of their products, it has been claimed. Scientists have accused major pharmaceutical firms of "medicalising" problems like high cholesterol or the symptoms of the menopause in a bid to increase profits.

Experts from around the world will meet in Australia today to discuss what they have labelled "disease-mongering". [...]
There are similar news articles here, here, and here.  

There are many points that one could make based upon the eleven "disease mongering" essays.  Today, though, I would like to focus on these, from the essay on Restless Legs Syndrome (RLS):
First, journalists should be very wary when confronted with a new or expanded disease affecting large numbers of people. If a disease is common and very bothersome, it is hard to believe that no one would have noticed it before. Prevalence estimates are easy to exaggerate by broadening the definition of disease. Journalists need to ask exactly how the disease is being defined, whether the diagnostic criteria were used appropriately, and whether the study sample truly represents the general population (e.g., patients at an insomnia clinic cannot be taken to represent the general public).

Journalists should also reflexively question whether more diagnosis is always a good thing. Simply labeling people with disease has negative consequences [21]. Similarly, journalists should question the assumption that treatment always makes sense. Medical treatments always involve trade-offs; people with mild symptoms have little to gain, and treatment may end up causing more harm than good.

Finally, instead of extreme, unrepresentative anecdotes about miracle cures, journalists should help readers understand how well the treatment works (e.g., what is the chance that I will feel better if I take the medicine versus if I do not?) and what problems it might cause (e.g., whether I might be trading less restless legs for daytime nausea, dizziness, and somnolence).
The point I would like to make is that we cannot rely on journalists to do this.  Readers should be able to do this for themselves.  News articles that contain glowing quotations from patients should be taking with the same degree of skepticism as celebrity endorsements.  Likewise, reports of unbelievably high incidence rates should raise some questions.  Plus, it is very dangerous to assume that the mere presence of an illness means that treatment is always appropriate.  Some conditions are best managed by leaving them alone.  

Having said that, I should also point out that it is entirely possible to take skepticism entirely too far.  As it happens, there probably are a lot of people out there who have undiagnosed and untreated RLS.  Many do not really need to be treated.  But in the most severe cases, RLS can lead to serious problems.  Persons with untreated sleep disorders may be at risk for automobile accidents.  They many underperform at work, which can threaten their livelihood.  They many underperform at home, which can lead to relationship problems.  So, it is important that we not ignore the warnings entirely.  The trick is to calibrate our skepticism the way we calibrate a laboratory test: if it is too sensitive, it generates a lot of false positives; not sensitive enough, and it misses real cases of illness.