KELLY MCEVERS, HOST:
Here is a set of numbers to get used to - 130 over 80. That is the new, more strict threshold for high blood pressure. The previous numbers were 140 over 90. The American Heart Association and 10 other groups revised the guidelines yesterday after reviewing years of studies.
And with us to talk about this is Dr. Harlan Krumholz. He's a cardiologist with the Yale School of Medicine. Welcome to the show.
HARLAN KRUMHOLZ: Hi.
MCEVERS: So just remind us why blood pressure is such an important measure of health.
KRUMHOLZ: So blood pressure, which is really the force of blood as it's expelled from the heart, turns out to be a critically important factor in the risk of heart disease and stroke, eye disease, kidney disease. The higher your blood pressure, the higher your risk. And we've known for a long time that if we bring that blood pressure down, then we can bring people's risk down.
MCEVERS: So then what led to this shift from 140 over 90 to 130 over 80 as the new measure for what is considered to be high blood pressure?
KRUMHOLZ: So a big question's always been, what's the right blood pressure? Believe it or not, it was only in the 1970s that studies began to be done that helped us understand this. There are stories of people like FDR whose blood pressure was routinely in the 200s. And of course, he died in disease that was related to his hypertension. And it turns out that some recent studies have pushed us in the direction of thinking that lower is actually better and that the numbers that we had settled on before, this 140 over 90, for some people may be still too high.
Those studies, particularly an NIH study, a National Institutes of Health study that recently came out, really demonstrated to us the possibility that we could help people more by getting their blood pressure lower. Again, for the highest-risk people, that's what the guidelines are recommending.
MCEVERS: So does this mean, though, that people who are listening who thought they were fine should now actually be worried if they are in that higher number?
KRUMHOLZ: So first of all, nobody should be worried. I mean, the way you are today is no different than you were yesterday. This new target, the 130 over 80, is really within the guidelines being recommended for high-risk individuals, people whose risk based on their other risk factors is elevated. Second, I think it represents an opportunity for people. That is, it opens a discussion about whether they want to set a goal for themselves with their clinicians that is a little lower than it was before, that this is essentially giving permission to say, we can think about strategies that can bring people down lower. And it may provide a benefit for those people.
MCEVERS: This change in the measure for high blood pressure does mean that a lot more people, especially people under 45, are now considered hypertensive, and that there's no more pre-hypertension. Will this change how they are treated?
KRUMHOLZ: Yeah, well, you know, my goodness, there's so many more people that will be labeled now with high blood pressure. I worry a little bit that people start thinking they have a disease and instead of recognizing that they have an opportunity perhaps to lower their risk even more. I will say that there remains some controversy, especially about treating very much older people and their degree of tolerance of getting their blood pressure very low. But the guidelines are recommending broadly that tens of millions more people might consider intensifying their treatment - that is, increasing doses or increasing meds, or even starting treatment when they wouldn't have started it before.
I think our hope is that as a result there will be a drop in the number of strokes and heart attacks and that people will do better. But this needs to be a discussion with doctors and patients. One thing worth highlighting for which there's widespread agreement is that we could be doing a better job in this country in helping people lower their blood pressure without using drugs.
Diet and exercise and helping people achieve closer to their ideal weights can have dramatic effects on blood pressure. In fact, people taking blood pressure medicines now even with the new guidelines might not even have to take pills at all if they could modify their diets slightly - more fruits and vegetables, lower amounts of salt - and more physical activity, lower stress or stress reduction strategies. And so there's widespread agreement now that we really need to be pushing in this direction to make it easier for people to achieve these kind of lifestyle changes and not just default to drugs all the time.
MCEVERS: Cardiologist Harlan Krumholz with the Yale School of Medicine, thank you very much.
KRUMHOLZ: Thank you.
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