By SARA ARTHURS
The American College of Cardiology and the American Heart Association have set new guidelines for what’s considered high blood pressure, announced in November. Dr. Brian Cole, a family medicine physician at Caughman Health Center, explained the condition and what all those numbers mean recently.
If the doctor says your blood pressure is, say, 140/80, Cole said the top number in the measurement is systolic blood pressure — that is the pressure in the arteries when the heart is pumping. The bottom number, diastolic blood pressure, indicates how much pressure your blood is exerting against your artery walls while the heart is resting between beats. So, Cole said, when medical personnel put a blood pressure cuff on your arm, what they are measuring is how hard the blood is pumping in the arteries. They apply pressure to the artery while listening to the pulse with a stethoscope, finding the level it takes to equalize the pressure at the heartbeat.
Blood pressure is measured in millimeters of mercury, or mm Hg, because mercury was used in the first accurate pressure gauges and is still used as the standard unit of measurement for pressure in medicine, the American Heart Association website states.
Cole said 140/90 had been considered “high” blood pressure — or stage 1 hypertension — prior to the new guidelines. The new standard lowers that, and there is also an associated risk if the top number is between 130 and 139, or the bottom number is between 80 and 89.
Under the new guidelines, 130/80 is considered stage 1 hypertension, and 140/90 is stage 2. The new guidelines also say that normal blood pressure is less than 120/80.
Cole said the new guidelines are trying to recognize that elevated blood pressure is a continuum. “It’s not a light switch” where you suddenly switch on to “at risk” at 140/90, he said. Instead, there’s a gradually increasing risk as the numbers rise.
So, Cole said, there are four quadrants: normal, elevated, stage 1 and stage 2 hypertension. Stage 1 is now with the top number between 130 and 139. Cole said not all of these people need treatment such as blood pressure medications, but they do need “to be more aware.” There are ways to decrease blood pressure without using pharmaceuticals, and at this lower stage it’s important to look at these methods.
Nearly half of American adults have high blood pressure, but many don’t know it, the American Heart Association website states.
High blood pressure puts you at risk of heart disease and stroke. There are other factors that also increase this risk including high cholesterol, diabetes, smoking and a family history of cardiovascular disease. Cole said blood pressure is one factor that can be controlled, adding that controlling cholesterol and diabetes can also decrease the cardiovascular risk. Anyone who has already had a stroke or heart disease, and is therefore at higher risk, might consider medications at stage 1, he said.
In addition to heart attack and stroke, high blood pressure can lead to kidney disease, vision loss, sexual dysfunction and peripheral artery disease, the American Heart Association website states.
Cole said someone who has high blood pressure won’t necessarily feel sick. You might feel the same at 150 as at 130. So blood pressure is considered “the silent killer,” he said, because people who have high blood pressure for a sustained period are putting increased pressure on their arteries. This creates changes in the walls of the arteries, making heart disease more likely.
Cole said losing weight can help, and so can avoiding excess alcohol consumption. But exercise helps even if it doesn’t result in weight loss, as the exercise itself decreases the arterial resistance. Sodium plays a role in blood pressure, too, and Cole said reducing salt intake may help.
Cole encouraged people to also be vigilant about checking their own blood pressure at home.
Medications for high blood pressure can work in different ways, Cole said. Some decrease the resistance of the arteries, some affect the heart’s work pumping the blood, some change how the kidneys influence the resistance of blood flow through the arteries, and some are diuretics intended to decrease blood volume.
Why one medication would be preferred over another may depend on many factors, but Cole said the goal is to find something that’s easy for the patient to take — ideally once a day — and has no adverse effects.