The first look at the joint European Society of Cardiology/European Society of Hypertension blood pressure guidelines was dominated by seeing what changed from the last iteration and what differed from the 2017 overhaul of the American College of Cardiology/American Heart Association guidelines.
However, both moved in the same direction and have more similarity than difference, Suzanne Oparil, MD, argued in an interview with ľֱ.
Oparil, of the University of Alabama at Birmingham, had co-chaired the 2014 JNC8 effort that resulted in unofficial recommendations after being disbanded by the NHLBI, was a key investigator on the SPRINT trial, and was a reviewer for the 2017 ACC/AHA guideline.
Selected comments from the interview follow:
How major are the differences between guidelines?
Oparil: I think that they're actually pretty consistent. Remember that the American guidelines, the ACC/AHA have the target less than 130/80 for everybody, expect low risk people and people who've had a previous stroke. That is not too far off from the 140/90 that the Europeans espouse, considering that they're not as strict about how to measure blood pressure.
The other thing that's different is that they're pretty firm about this treatment should be started with two drugs in a combination, fixed-dose tablet. We say not necessarily so. We start out with, if the blood pressure is only moderately elevated, one agent preferably in the maximum guideline-recommended dose and then add other agents over time. Those are the really major things.
They have moved in the same direction that we have in the sense that their previous target was 150 mm Hg systolic for elderly patients, which was same as JNC8. We've moved down further than they have, but it's a similar directionality.
Are you concerned about an initial two-antihypertensive combination strategy?
Oparil: There are two problems it could cause: 1) It could lower the blood pressure too much, or 2) the person could have adverse reaction to the combination medication and then you wouldn't know which drug was the offender. Actually, in the American guidelines, they say only if the pressure is more than 20/10 mm Hg over goal would you start with two drugs, so that's a little bit of a nuance and, I think, reasonable.
The argument for it was to minimize clinical inertia in improving control rates.
Oparil: That's a reasonable argument. What [writing group co-chair Bryan Williams, MD] was talking about is not too many doctor's visits. If somebody has to take of work to go back to their doctor to get a blood pressure pill dose titrated, or get another medication, that's very expensive for the nation as whole. But if you could get to goal faster, as long as it was safer, that's better. I agree with that. On other hand, what we see over here a lot is doctors think they're doing the patient a big favor if they start them on a very low dose of drug A, which doesn't really get them very far. Then they have to keep coming back for either titration or getting another drug ... We agree about that, it's just a different approach. We don't use combinations as much over here, in some cases because of cost.
Both guidelines used the same evidence, what accounts for the different philosophy on the SPRINT data?
Oparil: Everybody harps on SPRINT being the only trial. But if you do meta-analyses, there have been a number of meta-analyses showing that lower is better and that there's very little penalty of going to lower levels, at least in patients who are entered into a randomized controlled trial. Now, you don't pick people who are frail and falling all the time, or demented, or are not free living, or can't sign for informed consent. So it doesn't cover the whole population.
But if the person is basically mentally healthy, and reasonably physically able and free living, I think lower is better ... That's what the science says.
Now if you don't want to bother to have the patient do the 5-minute rest, if you don't want to bother to use the proper-size cuff, if you don't want to make sure the patient doesn't consume caffeinated beverages before the examination, then you probably do have to have a higher threshold. Maybe that's what they're factoring in -- that ordinary practices won't do the physical assessment of blood pressure properly. We make argument that they should do that. A procedure that adds a few minutes to an office visit, assuring that for such a huge patient population of many millions of people ,is more important than doing a lot of fancy tests for cardiovascular disorders, which is possible.
Does having different thresholds for diagnosis of hypertension between the two guidelines undermine their recommendations?
Oparil: I don't think so. I think there's this belief system in the U.S., if you're paying attention, you either accept U.S. guidelines, which are pretty well thought out, although they don't use that ... criterion that you have to have randomized controlled trial evidence for everything. They use meta-analyses and observational data to draw conclusions. So I think most people in the U.S. [accept the ACC/AHA guidelines] except for the primary care community, which doesn't like a mandate to more aggressive treatment that would cause them, the belief is, would require them to adhere to a higher standard and possibly be penalized if they couldn't get their patients to goal.
There's no different evidence. The Europeans couldn't cough up a different group of randomized trials or observational studies. It's just a different interpretation of the same data.
I think it's good that there is publicity for all of these guidelines because it brings more attention to hypertension. If there is a little bit of controversy, I think for people to be aware that the important issue is how common high blood pressure is and how important treatment is. Everybody agrees that lowering blood pressure is beneficial, but disagreements are relatively small about what the target should be, and exactly how the blood pressure should be measured, and what treatment should start with.