What you need to know about the new hypertension guidelines

No doubt you’ve heard that the American Heart Association and American College of Cardiology announced new hypertension guidelines this month. Mass media have been quick to point out that 50% of Americans now meet the criteria for hypertension, which is now defined as an average blood pressure of greater than 120/80. This is true and many Americans worry that they are now going to be expected to take more medications, to the benefit of Big Pharma. This isn’t true.

What was “pre-hypertension” in 2003 is now called “elevated blood pressure”

Why is 120/80 suddenly the bar above which you need to worry? In 2002 a study showed that the risk for developing cardiovascular disease (CVD), like stroke, heart attack, peripheral vascular disease, started to increase starting at a blood pressure of >115/75 and that for every 20/10 increase in blood pressure, the risk of dying from CVD DOUBLES. In 2010, high blood pressure was the leading cause of death and disability from CVD in the US and was second only to cigarette smoking as a preventable cause of death for any reason. 30-40% of children with hypertension will go on to have hypertension as adults. For adults without hypertension at 45 years of age, 84% or more will have hypertension over the next 40 years. So, hypertension is a serious problem and causes a lot of preventable deaths.

What are the categories of hypertension now?

Hypertension is categorized into different stages in order to guide doctors on how best to advise you about how likely your high blood pressure is to cause a heart attack or stroke and to emphasize the importance of intervening on high blood pressure early.

This means that if your blood pressure is 125/70, you have elevated blood pressure. If your blood pressure is 125/80, you have stage 1 hypertension.

If you progress from normal blood pressure to elevated blood pressure, your risk of heart disease and stroke increase by 10-50%. Going from normal to stage 1 hypertension increases your risk by 50-100%.

How do I know I have high blood pressure?

If you go to the hospital and your blood pressure is high when it wasn’t before, this doesn’t mean you necessarily have hypertension. Your blood pressure is determined by averaging the results of 2 or more measurements by a health professional on 2 or more separate occasions. Ideally, your blood pressure should be checked with you resting seated for 5 minutes, taken no sooner than 30 minutes after drinking caffeine, exercising or smoking, and taken with your arm resting on a table or supported by the person taking your blood pressure.

The size of the blood pressure cuff is also important. The inflatable bladder of the cuff should encircle 80% of the arm. Small cuffs will give you a falsely high blood pressure. If you are using a home blood pressure cuff, you should bring it to your doctor’s appointment so that its results can be compared with what your doctor’s office gets when they check. Checking your blood pressure at home can be very helpful for people with “white coat hypertension” – those whose blood pressure goes up when they visit the doctor. White coat hypertension does not carry the same risks of CVD as true hypertension and can account for 13-35% of people diagnosed as having high blood pressure.

Am I doomed if I have hypertension?

Only about 3.5% of people with hypertension have a genetic cause and 5-10% of people have an underlying disease that causes their hypertension. That means that the majority of people with elevated blood pressure can do things to improve their blood pressure. Things you can do to improve your blood pressure include: lose weight if you are overweight, follow the DASH diet, reduce sodium intake, improve potassium intake, moderate your alcohol intake, participate in exercise, stop smoking or exposure to second-hand smoke, control your blood sugar if you are diabetic, and improving your lipid profile if you have dyslipidemia (eg. High cholesterol).

How much good will it actually do for me to eat better and exercise?

Improving your overall health with weight loss, diet, exercise, and moderation in alcohol has measurable effects on lowering your blood pressure, whether you have hypertension or not.

This is how much each intervention can reduce your blood pressure:

From: J Am Coll Cardiol 2017;Nov 13:[Epub ahead of print].

Other non-medication interventions do not appear to have significant or long-term effects on reducing blood pressure. These interventions include consuming probiotics, increased protein or fiber, flaxseed, fish oil, calcium or magnesium supplements, other diets like low-carbohydrate or vegetarian diets, eating garlic, dark chocolate, tea, coffee, stress reduction interventions like guided breathing, yoga, transcendental meditation, and biofeedback. Eating a Mediterranean diet, however, has been shown to be effective in reducing your blood pressure, although not to the same degree as the DASH diet, as well as improve your lipid profile.

How do I know if I need medications to lower my blood pressure?

If you are older or have other risk factors for CVD (like high cholesterol, diabetes), you’re likely to benefit the most from lowering your blood pressure. So, if you have a history of CVD (you’ve had a stroke, TIA, angina, heart attack, peripheral vascular disease), your goal is to get your average blood pressure under 130/80.

If you have 10% or higher risk of having CVD in the next 10 years, your goal is also <130/80. If you are older than 79 years, then you automatically meet this criterion. If you are 45-79 years old and aren’t on a lipid lowering medication, use this risk estimator to determine your risk.

If you have no history of CVD and your estimated 10 year risk of CVD is <10%, your goal blood pressure is <140/90.

Some studies show that the lower your blood pressure, down to a systolic blood pressure of 120-124, the higher the benefit in preventing CVD and death from CVD. However, more studies will need to be done to see if we really should be recommending a lower blood pressure goal than currently.

Your doctor will likely want you to come back to the office to have your blood pressure rechecked within 3-6 months of starting blood pressure medication if you are of lower risk and within 1 month if you are at higher risk of CVD based upon your risk factors and age.

Regardless of what your blood pressure goal is, your efforts should also include lifestyle changes discussed above.

I hope this explanation of the new hypertension guidelines were helpful to you. Following a healthy diet, exercising regularly, maintaining a healthy weight, moderating alcohol consumption, stopping smoking, and controlling your diabetes and cholesterol can go a long way to avoiding cardiovascular disease, which leads to problems like heart attacks and strokes. There are, unfortunately, no shortcuts. If despite your best efforts you have hypertension, anti-hypertensive medications have been proven to reduce your risk of developing and dying from CVD.

Author: Dr. Irene Tien Emergency Medicine and Pediatric Emergency Medicine