How does that work, you may ask? Easy. You simply change the definition of the disease. Observe:
In 2000, the major cardiology professional organizations formally changed the definition of heart attack (or myocardial infarction, MI), basing it on the measurement of a very sensitive blood test called the troponin test. This change appears to have resulted in an extra 250,000 diagnoses of heart attack in the U.S. each year. Then, in 2007, they tweaked the definition once again, in a way that expanded the reported prevalence of MI in the U.S. by another estimated 25%.
Both of these changes in definition were justifiable, and most likely have helped patients. But, as a side effect (or perhaps a side benefit) they created a heart attack epidemic.
If you are a cardiologist, an epidemic of MIs may not be such a bad thing. Not only do you get to perform more invasive procedures (for a condition that, even insurance companies must admit, clearly warrants all the high-tech stuff you can muster), but also, such an epidemic can be easily parlayed by organizations like the American Heart Association (AHA) into a major fundraising campaign. Furthermore, the substantially higher prevalence of MIs provided an important boost to the AHA a few years ago, when it went up against the American Cancer Society over whose was bigger (that is, whether cancer or cardiovascular disease is the leading cause of death in Americans) - an important question for fundraising purposes.
In a similar fashion, the American Society of Hypertension changed the definition of hypertension in 2003, creating a brand new category of people with abnormal blood pressures (called "pre-hypertensives"). And so, we have a new hypertension epidemic on our hands. (Here's some information on hypertension.)
And then there's the fateful night at the end of the last decade when 30 million Americans went to bed at a reasonably healthy weight, and woke up overweight or obese, thanks to a formal change in the definitions by the NIH. We are, in truth, getting fatter as a nation, but the new definitions of "overweight" and "obese" created a quantum leap, literally overnight, in the number of us who are officially too fat. The obesity epidemic, in other words, is man-made in more ways than one.
Studies suggest that much of the current "autism epidemic" may not be due to an actual increase in the prevalence of this disorder, but instead, may be the result of our improved understanding and awareness of autism, and to an expanded definition of autism (i.e., the "autism spectrum disorders") that captures individuals who have relatively milder forms of the disorder, and who would have been missed a few years ago. (DrRich recognizes that this viewpoint is politically incorrect, especially since the "vaccines-cause-autism" school of thought relies entirely on a major increase in the prevalence of autism.)
Then there's the remarkable story of the metabolic syndrome epidemic. Metabolic syndrome - a series of risk factors centering around obesity and insulin resistance, that, taken together, produces a substantial increase in the risk for cardiac disease - was invented by endocrinologists, and taken up as a great cause, and subsequently heavily promoted, by the American Diabetes Association (ADA) - and with great success.
The ADA's success was too great, as it happened. For even the cardiologists (who are not known for their appreciation of metabolism) eventually noticed it - and took it up for themselves. The next thing you knew, people recognized as having metabolic syndrome were being referred to cardiologists instead of diabetes specialists or endocrinologists. The inventors of the epidemic were boxed out.
Astoundingly, the ADA reacted by suddenly disowning metabolic syndrome altogether, asserting publicly that there’s actually no such thing after all (and so please disregard our strenuous decade-long public campaign to the contrary). Rather, there’s a condition called “pre-diabetes” that, remarkably, has the same features of metabolic syndrome (but, obviously, given the name, would require a patient to seek the counsel of a diabetes specialist).
Too late. The relatively tiny ADA stood no chance against the mighty American Heart Association, which continues to promote the metabolic syndrome epidemic with great vigor, and which ridicules the ADA’s lame attempt to “cure” the metabolic syndrome problem by denying its existence. Subsequently, metabolic syndrome has flourished (if it actually exists, up to 40% of American adults have it), and so have the cardiologists.
DrRich's point, of course, is that healthcare "epidemics" over this past decade have become quite popular - even to the point of becoming the objects of professional turf wars. Often they do not reflect any actual change in the incidence of a disease, but rather, merely a change in the way the disease is defined.
The professional groups and governmental agencies that "goose" things along by redefining a disease, then rely on the resultant epidemic for fundraising (or other benefits), may not be in the same category as the pyromaniac who torches a building, then collects kudos as one of the brave firemen fighting the blaze. But it must be admitted that such "epidemics" often have a very salutary effect on one medical specialty or another. And because journalists are always ready to frighten all of us by tossing the "E-word" around at every opportunity, we can expect this "epidemic of epidemics" to continue well beyond the end of this decade - if not this millennium.
