New guidelines suggest that people with no history of cardiovascular disease may not benefit from more aggressive treatment.
High blood pressure remains a strong indicator for heart attack or stroke risk. But how high is too high?
The American College of Physicians (ACP) and the American Academy of Family Physicians (AAFP) recently released updated guidelines for treating hypertension (high blood pressure) in adults ages 60 and older.
Based on a systematic review of 21 published trials, the new guidelines — which were published in the March/April 2017 Annals of Internal Medicine — suggested doctors treat people with no history of heart disease only if their systolic blood pressure (the top number in a blood pressure reading) is 150 millimeters of mercury (mm Hg) or higher.
This conflicts with current recommendations from the American Heart Association, the American College of Cardiology, and the CDC, which consider people to have high blood pressure at 140 mm Hg or higher (150 mm Hg or higher for those ages 80 and older). The problem with all guidelines is that they tend to remove individual considerations, says Dr. Randy Zusman, director of the Division of Hypertension at Harvard-affiliated Massachusetts General Hospital.
“Guidelines are just that — guidelines,” he says. “They should not be applied to everyone, and the message here is that when it comes to treating high blood pressure, it should not be based on a number, but rather the person.”
The numbers game
Hypertension affects almost 65% of adults ages 60 and older, according to the National Center for Health Statistics. Lifestyle changes are still the primary approach to treatment. This includes not smoking, drinking only in moderation, exercising more, losing weight, and monitoring your diet, including your salt and sugar intake.
However, blood pressure medications like thiazide-type diuretics, calcium-channel blockers, ACE inhibitors, and angiotensin-receptor blockers are also used to help aggressively drive down higher blood pressure.
The question is, when do you begin treatment? When is your blood pressure too high? And how low is low enough?
“Guidelines for a disease as common as hypertension, which overlaps with other illness like diabetes, heart disease, and high cholesterol, are tough to apply to an individual,” says Dr. Zusman. “The right blood pressure number really depends on your health condition.” For example:
Moderate or severe hypertension. The ACP/AAFP research found that the greatest benefit for aggressively treating high blood pressure came from people with moderate or severe hypertension — higher than 160 mm Hg — who lowered their blood pressure to 140 mm Hg. Yet, there was no advantage for lowering blood pressure any more than that.
History of stroke. The guidelines also said that among people with a history of stroke, there was good evidence that driving blood pressure down to between 130 and 140 mm Hg could reduce the risk of another stroke — but not a heart attack or death from any other cause.
Diabetes and obesity. The ACP/AAFP study noted that many of the reviewed studies did not include people with additional serious health conditions, such as diabetes and obesity, but that other research suggests that people with these conditions often battle high blood pressure.
Treating before it gets worse
What do these guidelines mean for older men with no current risk factors or family history of heart disease? Should they even worry about the new numbers?
Dr. Zusman explains it like this: “If it’s best to have a lower blood pressure after heart attack or stroke, doesn’t it make sense to have a lower blood pressure, within reason, before it happens?”
Even if your blood pressure is fine now, no matter your potential risk, don’t wait until the number creeps into the danger zone to take action.
“Everyone should check with their doctor to determine the best range for them, get an accurate blood pressure reading, and then monitor it regularly,” says Dr. Zusman. “Blood pressure doesn’t suddenly jump. It’s a gradual process, and when there’s a steady upward trend, that’s when you need to begin lifestyle strategies.”
The takeaway message here is that for a person at average risk, blood pressure medications are probably not as important for mildly elevated blood pressure.
But for those already on these medications, it may be good idea to aim for a lower target if they can tolerate the drugs without side effects.
Your doctor can determine the best range of blood pressure for you. Once you get an accurate reading, regularly monitor it at home for any changes.
How low should you go?
Is there any advantage to driving blood pressure even lower than the suggested numbers? The science is a bit conflicted.
For instance, a 2015 study in The New England Journal of Medicine found that people in the SPRINT trial with hypertension or at high risk for heart disease who dropped their blood pressure to 120 mm Hg had a 25% lower risk of dying from a heart attack or stroke and 27% fewer deaths from any cause after more than three years compared with those who lowered it to 140 mm Hg.
Yet, an observational study published Oct. 29, 2016, in The Lancet, which looked at more than 22,000 people in the CLARIFY trial with coronary artery disease, found that lowering their blood pressure into the range of below 120 to 129 mm Hg was associated with a 56% increased risk for heart attack, stroke, and death.
Blood pressure numbers are never exact, and what is best for one person may not be right for another, says Dr. Zusman. “It’s doubtful experts will ever agree on one firm number for everyone. It’s best to consult with your doctor to determine which range is ideal for you and your current health.”
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