A few weeks ago, the American Heart Association and American College of Cardiology revealed new guidelines for managing hypertension in adults, changing the target for systolic blood pressure to less than 130 (the previous target was 140; 150 for those age 60 and older). We asked some experts to learn more about what these guidelines mean for primary care doctors and patients.
The new guidelines are based on results of a large, federally funded study called SPRINT, which found a 25% reduction in cardiovascular events using a lower blood pressure target. This sounds like an impressive change, but it looks much less impressive when you consider the absolute percentage change, that is, the number of people actually helped by the intervention.
As Dr. Gilbert Welch points out in a New York Times op-ed, the absolute reduction in cardiovascular events was only 2% – from 8% in the group with less aggressive treatment to 6% in the group with more aggressive treatment. Welch also notes that SPRINT used an especially high-risk population, so patients with low or average risk for cardiovascular events may not benefit as much.
The results from SPRINT are inconsistent with past studies that found an increase in mortality from aggressive blood pressure treatment for patients with chronic renal disease and diabetes, writes Dr. Andy Lazris, primary care doctor and Right Care Alliance council chair, on his blog, Curing Medicare. Although the SPRINT study did not find a significant difference in serious adverse effects between the intervention and control group, Lazris points out that non-serious side effects such as dizziness and confusion are common among elderly patients taking blood pressure medication.
The AHA and ACC assume that a lower blood pressure is always better, but some primary care doctors challenge that doctrine. “Once you get to a certain point, if you lower blood pressure further, your rate of stroke and heart attack increases,” says Lazris. Lazris also notes that blood pressure can differ from minute to minute, so basing treatment decisions off of one reading could be misleading.
It’s beneficial that these guidelines are pushing awareness of cardiovascular disease, but aggressive blood pressure treatment might not be appropriate for all patients, especially elderly patients.
“Treating blood pressure with medicine is a risky intervention,” says Dr. Ronald Adler, associate professor of family medicine & community health at the University of Massachusetts Medical School. “While you may lower the risk of some cardiovascular events, medications can cause adverse effects such as kidney and electrolyte abnormalities, not to mention the increased risks of complications such as dizziness and falls that inevitably result when BP is lowered too much,” says Adler, “Because the new guidelines suggest that people be treated initially with 2 drugs, such experiences will be even more common.”
Primary care doctors may have different approaches to managing blood pressure in their patients, based on their patient population and patient preferences. If a doctor with mostly elderly patients strives to keep them off additional medications, could she acknowledge the guidelines without changing her practice for every patient? As of now, the guidelines are not binding, but if they get embedded in quality measures, which is likely, doctors will be graded on how well they get patients to the new hypertension target. These grades may affect doctors’ pay or even the sustainability of their practice.
“If I lower my patient’s blood pressure and they fall and break their hip, I still get paid,” says Lazris. “But if their blood pressure is above the target, I fail the guideline.” The penalty for failing more than 10% of guidelines can be as high as $80,000 a year, which can make or break a primary care practice.
“Increasingly these grades are getting pushed out into the public domain, so if you score badly [on hypertension], patients could leave,” says Adler, “This grading system creates a tension between doing the right thing for the patient and doing what’s best for you.”
The ACA guidelines recommend that doctors encourage lifestyle changes before turning to medication for patients with high blood pressure, but some worry that the guidelines will just lead to more medication. It’s much easier to give a patient a prescription than try and change hard-wired lifestyle habits, and the medication route is especially tempting if doctors are under pressure to deliver quick results.
The new guidelines are extraordinarily aggressive, essentially classifying 46% of adult Americans as hypertensive, while pathologizing a new category the authors call “elevated BP”; this includes people with systolic BP 120-129. They even call for people in this category to be seen by a health care provider every 3 – 6 months. That’s a lot of time for primary care doctors to be seeing otherwise healthy patients when they have so many other patients to see.
Doctors like Lazris and Adler are speaking out in the hopes that these guidelines will not become binding quality measures, but if the new blood pressure target becomes a reality, overtreatment of hypertension will likely follow.
There are elements of the new guidelines that are enthusiastically embraced by primary care clinicians. Shining a light on cardiovascular health and optimizing lifestyle to improve this through diet and exercise are universally applauded, though Dr. Adler notes this would be better accomplished through public health interventions rather than through individual medical visits. He also highlights two other positives, noting that out-of-office BP measurements should be used to confirm a diagnosis of hypertension and to guide treatment because such measurements correlate better with patient outcomes, and that optimal treatment plans should be established through shared decision-making between patients and clinicians.