High blood pressure (hypertension) is a major risk factor for cardiovascular disease, and treating it prevents serious cardiovascular consequences.
But what level of blood pressure should be treated?
Many people have blood pressures in an intermediate zone. Depending on the value you choose, your decision affects millions of people.
The debate about a threshold has been going on for decades. For a long time, the threshold was 140/90. If your blood pressure was higher, you had hypertension. If it was lower, you did not. If you had hypertension, you needed to do something to lower your blood pressure.
But the whole idea of a numerical threshold was silly. The risk associated with hypertension is not binary. It does not become real when you exceed a certain number, and it does not fully subside when you are below it. The risk is continuous; the higher the number, the higher the risk.
Nevertheless, medicine is political, so if it is possible to wage a war, you can rest assured that there will be a war.
Last year, the American Heart Association, the American College of Cardiology and many other cardiology organizations announced that the threshold for identifying hypertension had been officially lowered. The threshold for diagnosing and treating hypertension was now 130/80.
If the idea of a bright-line threshold is scientifically meaningless, what were the reasons for making a change? The cardiology organizations issued a 200-page explanation. This is not a must-read. Nothing in the 200-page document represents an epiphany.
The document relies in part on the findings of the SPRINT trial, but no one really understands the blood pressures in that study. Strangely, the document applies its recommendations to people who were not even represented in the SPRINT trial. For example, it applies its recommendations to those with heart failure, even though there is no scientific basis for doing so.
Nevertheless, suddenly, 46% of Americans had hypertension. On the previous morning, 32% had the disease. Within 24 hours, millions of people were given a new label.
Furthermore, millions of people who thought they had well-controlled blood pressure (because it was below 140/90) now learned that they needed to do more to bring their blood pressures down.
The reaction has been surprisingly muted, possibly because many have quietly ignored the new declaration. If cardiologists wanted to encourage everyone to be a bit more aggressive in treating blood pressure, they had sent a message.
But some organizations didn't appreciate the action and said so publicly. In December, the American Academy of Family Physicians (AAFP) said they were not endorsing the new hypertension guideline.
What threshold did the AAFP think was appropriate? The group had developed a document with the American College of Physicians which proposed a target systolic blood pressure of 150 for people who were 60 years or older. Earlier this week, the ACP doubled down, issuing a statement criticizing the lower threshold.
Why did the AAFP and ACP decline to adopt the guideline proposed by cardiologists? There are many reasons. However, I also understand that primary care physicians really dislike it when specialists tell them what to do.
So if you previously thought that a threshold of 140 was important, within the span of one year, cardiology organizations brought that threshold down to 130, and primary care organizations brought that threshold up to 150.
What should you do?
I have been entertained. Since there is no magic number that describes the risk associated with high blood pressure, there has been nothing to fight about.
So why are cardiologists and primary care physicians at war?
Here's my response: Why do children get into mud fights?
Answer: Because they enjoy acting like children.
Disclosures
Packer recently consulted for Amgen, AstraZeneca, Bayer, Boehringer Ingelheim, Cardiorentis, Daiichi Sankyo, Gilead, Novo Nordisk, Relypsa, Sanofi, Takeda, and ZS Pharma. He chairs the EMPEROR Executive Committee for trials of empagliflozin for the treatment of heart failure. He was previously the co-PI of the PARADIGM-HF trial and serves on the Steering Committee of the PARAGON-HF trial, but has no financial relationship with Novartis.