While the measurement of blood pressure has been among the most common medical practices for over a century, the results are undergoing a reinterpretation—one that tells over half of U.S. adults that they need to make a change.

You roll up your sleeve. The nurse puts the cuff around you bicep. You feel the squeeze, which slowly lightens with a hissing sound. There’s no medical procedure you’re more familiar with, and no medical procedure that seems less eventful.

But if two of you are reading this together, statistically one of you should be concerned with what this most common of tests tells you. That’s what the American College of Cardiology, in concert with the American Heart Association, said in November, when they announced their new definition of what constitutes high blood pressure, a move that newly categorized 72 million people as unhealthy.

That huge number reflects how many adults have blood pressure somewhere between 140/90 (pronounced “one-forty over ninety”), the number that since 2003 has been considered the threshold of hypertension, and 130/80, the new threshold. What hasn’t changed is the classic 120/80, the top end of what’s considered “normal.” (General rule of thumb: lower is better.)

Why any change at all? To put it simply, new data, which is the catalyst for updating blood pressure guidelines (as opposed to being updated at regular intervals, as is the case for some other clinical practice guidelines). “People with [systolic (i.e., the top number)] blood pressure levels between 130 and 140 are at about twice the risk of heart attack and stroke as people with normal levels,” the National Heart, Lung, and Blood Institute’s David Goff told Science News, paraphrasing certain findings from the Systolic Blood Pressure Intervention Trial, a five-year study of more than 9,300 adults ages 50 and older—one of over 900 studies reviewed in the creation of the new guidelines.

"We want to be straight with people,” says Paul K. Whelton, the guidelines’ lead author. “[…] If you already have a doubling of risk [of heart attack and stroke], you need to know about it. It doesn't mean you need medication, but it's a yellow light that you need to be lowering your blood pressure, mainly with non-drug approaches."

Those approaches are well known: exercising regularly, losing excess weight, eating healthy, limiting your intake of sodium and alcohol, quitting cigarette smoking, better stress management. As for drugs intervention, the guidelines authors say approximately 4 million more U.S. adults are projected to require medication, a 1.9% increase over the number recommended under the previous guidelines.

Guidelines co-author Robert Carey notes that one of the changes has been to eliminate the category “prehypertension,” formerly where persons with a systolic pressure reading between 120–139 and diastolic pressure (i.e., the bottom number) between 80–89 would have found themselves. “[W]e have eliminated the term ‘prehypertension,’ because we really didn’t think it conveyed enough importance,” he said in November.

Just so you can keep the numbers straight, the new guidelines at a glance:

• Normal BP: 120/80 and below
• Elevated BP: Systolic between 120–129 and diastolic less than 80
• Stage 1 Hypertension: Systolic between 130–139 or diastolic between 80–89
• Stage 2 Hypertension: Systolic above 139 or diastolic at least above 89
• Hypertensive crisis: Systolic above 180 and/or diastolic above 120

The guidelines’ authors encourage everyone—that means you—to have a blood pressure monitor at home and to regularly check your numbers. Harvard Men’s Health Watch recommends one that goes around the upper arm (other types tend not to be as precise), which can be purchased for as little as $40.

Taken all together, Dr. Goff calls this “a new approach for blood pressure management” that “really highlights the importance of preventing high blood pressure in the first place.” And staying on top of your situation helps you to do so with minimal effort. “Small changes are important,” he says. “You don’t need to make big changes all at once.”

About the Author:

Except for a four-month sojourn in Comoros (a small island nation near the northwest of Madagascar), Greggory Moore has lived his entire life in Southern California. Currently he resides in Long Beach, CA, where he engages in a variety of activities, including playing in the band MOVE, performing as a member of RIOTstage, and, of course, writing.

His work has appeared in the Los Angeles Times, OC Weekly, Daily Kos, the Long Beach Post, Random Lengths News, The District Weekly, GreaterLongBeach.com, and a variety of academic and literary journals. HIs first novel, The Use of Regret, was published in 2011, and he is currently at work on his follow-up. Contact: [email protected]