Redefining Hypertension: A Redefinition Throwback to Polio
Published March 24, 2018 | OpinionOn Nov. 13, 2017, the American College of Cardiology (ACC) and the American Heart Association (AHA) changed their guidelines for defining hypertension. They lowered the range for defining high blood pressure. Under the old guideline, a person was determined to have high blood pressure if their systolic blood pressure measures 140 mmHg (millimeters of mercury) or more and their diastolic blood pressure measures 90 mmHg or more. Under the new guideline, a person is considered to have high blood pressure if their systolic blood pressure is 130 mmHg or more and their diastolic blood pressure is 80 mmHg or more.1 2
The systolic blood pressure number measures the pressure in the blood vessels when the heart beats. The diastolic blood pressure number measures the pressure in the blood vessels when the heart rests between beats.3
According to a news article published by the ACC, “The new definition will result in nearly half of the U.S. adult population (46 percent) having high blood pressure, with the greatest impact expected among younger people. Additionally, the prevalence of high blood pressure is expected to triple among men under age 45, and double among women under 45.”1
Now, let that fact sink in for a minute. Merely by changing the definition of what constitutes high blood pressure, two medical associations succeeded in giving tens of millions of Americans a serious medical condition almost overnight. Prior to Nov. 13, 2017, about 75 million (29 percent) adults in the United States had high blood pressure. As of Nov. 13, the number of American adults suffering from high blood pressure dramatically jumped from one in three to nearly one in two—creating a much larger “at risk” population of more than 100 million adults in the U.S.3
Suddenly, a lot more Americans who did not require medication to help lower their blood pressure before will now be prescribed blood pressure medication by their doctors. What has changed in terms of their health? Absolutely nothing. All that happened was that two medical trade associations got together and decided to change the definition of an adverse health condition.
While, on paper, it may look like many more American adults started to develop hypertension after 2017, the reality is different. What has changed is not the heart health of Americans but rather what two medical trade associations have decided to define as the heart health of Americans.
This sort of administrative tinkering is reminiscent of what occurred in 1954 when the U.S. government decided to redefine polio. Prior to 1954, to be classified as having paralytic poliomyelitis a patient had to show symptoms of paralysis for only 24 hours. In 1954, public health officials tightened the time guideline so that in order to be classified as having paralytic poliomyelitis a patient had to exhibit paralytic symptoms for at least 60 days. Almost overnight, thousands of Americans who would have previously been diagnosed as having polio were no longer considered to have polio.4 5 6 7
Predictably, in 1955 the number of polio cases in the U.S. dropped dramatically. In 1952, a total of 52,879 people got polio in the U.S. In 1953, 35,592 Americans contracted polio. In 1954, the number was 38,476. In 1955, it was 28,985. These sharp declines happened to coincide with the introduction of the inactivated injectable polio vaccine (IPV) by medical researcher and virologist Jonas Salk, MD in 1954.4 5 6 7
It has long been assumed by most people that the Salk vaccine was responsible for the decline in polio cases during the mid-1950s. In fact, the downward trend commenced several years before the vaccine was introduced and one of the most significant declines in cases occurred in 1955, the year after the disease was curiously redefined.
The difference between the redefining of polio in 1954 and the redefining of hypertension in 2017 is that the former decreased the number of people with a disease while the latter increased the number of people with a condition. What do the redefinitions have in common? The administrative move by public health officials in 1954 was used to help justify ramping up the number of vaccines administered to children and adults. Similarly, the administrative move last year will be used to justify ramping up the number of blood pressure medications prescribed to children and adults.
In the future, a lower number of deaths of Americans due to hypertension relative to the number of Americans diagnosed with that condition may be cited as evidence that the medications administered for high blood pressure worked and, thus, should be prescribed more widely. But the reality may be that the apparent relative declines in the number of deaths due to hypertension will simply have been due to the arbitrary sudden increase in the number of people with high blood pressure due to the redefinition of the condition.
This playing fast and loose with the facts is how history sometimes can get manipulated and distorted so that the truth of what happened gets obscured and lost. Science is not immune to this process.
Imagine how differently the history of vaccination may have evolved over the past half century had the illusion, which government health officials proceeded to create with regard to polio in 1954, been widely known and understood back then.