Tag Archives: SPRINT

Becoming Enlightened About More Stringent Blood Pressure Goals: Sapere Aude!

The skeptical cardiologist and many of his patients with hypertension have a decision to make: what should our BP goal be?

Given that we have data now on over 1 million patients one might think that the answer would be clear and that there would be a consensus amongst all the experts.

Messerli and Bangalore, writing in a recent special hypertension issue of JACC, however, clearly articulate the “blood pressure landscape schism” that currently exists.

This figure from their paper (subtitled “Schism Among Guidelines, Confusion Among Physicians, and Anxiety Among Patients”) shows the marked difference in BP goal and treatment recommendations for the same patient in recent American and  European Cardiology and American Family Practice Guidelines.

The 2017 American College of Cardiology (ACC)/American Heart Association (AHA) guidelines—which aide approximately 25,000 cardiologists in the United States—indicate that her BP should be <130/80 mm Hg (1). The 2018 European Society of Hypertension (ESH)/European Society of Cardiology (ESC) guidelines—which aide approximately 75,000 physicians—indicate that her BP should be <140/90 mm Hg (2). The 2017 American College of Physicians (ACP)/American Association of Family Physicians (AAFP) guidelines—which aide approximately 250,000 family practitioners and internists in the United States—indicate that her BP should be <150/90 mm Hg

 

 

 

 

 

 

 

 

 

 

 

Messerli and Bangalore use a second figure to graphically illustrate the potential consequences of the differing guidelines.

Stroke Mortality for Upper Limit of On-Treatment Systolic Target BP as per Various Guidelines Absolute risk of stroke mortality is 5% for the suggested on-treatment target BP of the ACC/AHA guidelines, 8% for target BP of the ESH/ESC guidelines, and 14% for target BP of the ACP/AAFP guidelines. Abbreviations as in

Cardiovascular death rates thus may vary three-fold depending on what BP goal we choose.

This marked variation in treatment recommendation highlights that they

are not only an evaluation and interpretation of evidence in question, but also a judgment weighted by personal, regulatory, and organizational preferences that can vary from physician to physician within a country and across geographical regions.

Physicians and patients (hopefully through shared decision making) are going to have to do some thinking on their own.

Messerli and Bangalore quote Immanuel Kant in this regard:

Enlightenment is man’s emergence from his self-imposed nonage. Nonage is the inability to use one’s own understanding without another’s guidance. This nonage is self-imposed if its cause lies not in lack of understanding but in indecision and lack of courage to use one’s own mind without another’s guidance. Dare to know! (Sapere aude.) “Have the courage to use your own understanding,” is therefore the motto of the enlightenment.

As a 64 year old who has emerged from his nonage with hypertension, I have carefully examined the latest American hypertension guidelines especially in light of the SPRINT study and elected to add a third anti-hypertensive agent to get my average BP below 130/80. It’s worked for me with minimal  side effects but I carefully monitor my BP.

If I notice any symptoms (light-headed, fatigued) suggesting hypotension associated with systolic BP <120 mm Hg I tweak my medical regimen to allow a higher BP.

Like all of my patients I would prefer to be on less medications, not more but when it comes to enlightenment about the effects of hypertension, it is now clear that lower is better for most of us in our sixties down to at least 130/80*.

Sapere Audaciously Yours,

-ACP

*N.B. In the SPRINT study the BP was obtained using an automatic BP cuff after 5 minutes of rest with the patient unobserved and averaging 3 recordings one minute apart.

This “research grade BP” averages about 12 mm Hg less than a routine single clinic obtained BP (see here.)

The BP Schism

SPRINT Trial Data Suggest We Should Be Aiming For Lower Blood Pressure Goals

Would you rather have a systolic blood pressure (BP)  of 120 mm Hg or 140 mm Hg?

Prior to a week ago this sometimes skeptical cardiologist thought treating hypertensive patients to the lower BP didn’t necessarily help  avoid death from cardiovascular disease, heart attacks or strokes and that it resulted in more side effects.

Clinical trials have shown that treatment of hypertension reduces the risk of cardiovascular disease outcomes, including stroke (by 35 to 40%), heart attacks (by 15 to 25%), and heart failure (by up to 64%) but the target for systolic blood-pressure lowering has been uncertain.

I wrote in “Home Versus Office Blood Pressure and the “Landmark” NIH Blood Pressure Trial” about the somewhat premature announcement of the SPRINT NIH trial on blood pressure previously.

With the recent  publication of the SPRINT trial data (A Randomized Trial of Intensive versus Standard Blood-Pressure Control — NEJM.) there is now impressive evidence supporting the lower target BP and apparently with minimal side effects.

The SPRINT trial randomized almost ten thousand patients and compared the effects of antihypertensive treatment with a systolic blood pressure (SBP) target of <120 mm Hg (intensive treatment) versus <140 mm Hg (standard treatment).

They studied hypertensive adults ≥50 years of age who had an average SBP of 130–180 mm Hg (the acceptable upper limit decreasing as the number of pretrial antihypertensive medications increased) and were at additional risk for cardiovascular disease (CVD).SPRINT was designed to recruit study participants with an average CVD risk of ≈2% per year, equivalent to a Framingham 10-year CVD risk score of 20%.

To understand if these trial results apply to you it is important to know what patients were enrolled in the study (inclusion and exclusion criteria) and I’ve listed these at the end of this post.

The SPRINT trial found that cardiovascular events like stroke and heart attack and death from these cardiovascular causes was lower by 25% in those patients treated intensively.  Overall death was lower by 27%

Average systolic blood pressure was 121 mm HG in the intensive therapy group and 134 mm Hg in the standard therapy group.

Drugs used were: thiazide-type diuretics, calcium channels blockers, and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. Other agents, including spironolactone, amiloride, β-blockers, vasodilators, or α-receptor blockers, could be added if necessary. On average, 2.8 drugs were used in the lower BP group versus 1.8 in the higher BP group.

This more intensive BP treatment was surprisingly well tolerated. Very surprisingly, orthostatic hypotension, (drop in BP on standing I talked about in my post on burpees and dizziness) was significantly more common in the standard than in the intensive arm. I would have expected this opposite.

There were  significantly more kidney problems and electrolyte abnormalities in the intensive group compared to the standard therapy group.

This study provides a very powerful argument for shooting for a BP of 120 in many of my patients.

And the skeptical cardiologist (who splits BP pills )will be aiming for a lower BP in himself.

It’s important to replicate how BP was measured in the SPRINT trial if we are to apply the results. As the authors have written elsewhere:

“be mindful of the manner in which BP was measured in the trial: an average of 3 office BP readings taken with proper cuff size, participants seated with their back supported, 5 minutes of rest before measurement, and no conversation during the rest period or BP determinations. In SPRINT, this was achieved using an automated manometer (Omron Healthcare, Lake Forest, IL) that was preset to wait for 5 minutes before measurement, as well as to take and average the 3 readings. BP measurements taken without observing these conditions are likely to overestimate BP6 and result in over treatment, with the potential for higher rates of serious adverse effects and greater utilization of resources.”

Pressurelessly Yours

-ACP

And the entry criteria:

 Increased cardiovascular risk was defined by one or more of the following: clinical or subclinical cardiovascular disease other than stroke; chronic kidney disease, excluding polycystic kidney disease, with an estimated glomerular filtration rate (eGFR) of 20 to less than 60 ml per minute per 1.73 m2 of body-surface area, calculated with the use of the four-variable Modification of Diet in Renal Disease equation; a 10-year risk of cardiovascular disease of 15% or greater on the basis of the Framingham risk score; or an age of 75 years or older. Patients with diabetes mellitus or prior stroke were excluded