What do those numbers mean?
Blood pressure is expressed as two numbers because it’s a combination of two measurements: systolic pressure and diastolic pressure. The first is the pressure that blood flow exerts on the artery walls when the heart beats; the second is the pressure that exists between beats, when the heart is resting. A typical blood pressure reading for an adult might be 120/80 (“120 over 80”). The “top” number, 120, refers to the systolic pressure and the “bottom number,” 80, to diastolic pressure. Higher numbers indicate higher blood pressure—and greater danger to your health. A person is said to have high blood pressure when three or more readings measure 140/90 or greater, but more recent guidelines classify anyone with systolic pressure between 120 and 139 and diastolic pressure between 80 and 89 as having “prehypertension”—meaning they’re likely to develop hypertension. In people over age 50, systolic pressure is more important than diastolic. Ask your doctor to explain your blood pressure reading to you.
Drugs that treat hypertension
- Diuretics lower blood pressure by ridding the body of excess fluid and salt.
- Beta blockers protect the heart from overstimulation, thereby decreasing its workload.
- Sympathetic nerve inhibitors prevent blood vessels from constricting, or closing, too much.
- Vasodilators cause blood-vessel walls to relax and widen.
- ACE inhibitors control the body’s production of angiotensin, a hormone that raises blood pressure.
- Calcium channel blockers keep the heart from contracting vigorously and allow the blood vessels to dilate by blocking the entry of calcium into muscle cells. This relaxes the heart and the vascular system, which reduces blood pressure.
Franklin Delano Roosevelt will always be remembered as the president who was wheelchair-bound because of polio. What was invisible to the American public was FDR’s more serious illness—high blood pressure. This disease, in fact, led to congestive heart failure and, ultimately, to the massive cerebral hemorrhage that killed the president in 1945.
As many as 72 million Americans ages 6 and older have high blood pressure, meaning that their blood travels through their arteries at a pressure too high for good health. Known medically as hypertension, this “equal opportunity” disease can strike anyone: male or female, rich or poor, city or country dweller, stockbroker, farmer, housewife—or president.
Understanding the risks
A temporary rise in blood pressure is a normal response to stress or physical exertion. But people with hypertension have high blood pressure at rest, which is extremely dangerous. Chronic hypertension causes atherosclerosis, or clogging of the arteries, which can lead to a heart attack. Left untreated, hypertension also can lead to stroke, heart failure, kidney damage and retinopathy (severe damage to the retina of the eye, which can cause blindness).
Why it’s dangerous
High blood pressure is a sign that your heart is working harder than normal. Over time, uncontrolled high blood pressure triggers serious problems. All that extra work makes the heart muscle grow larger and less efficient. The arteries become less elastic, making them susceptible to arteriosclerosis (hardening of the arteries) and atherosclerosis (clogged arteries). Narrowed vessels hamper circulation, so tissues and organs may not get enough blood. If the kidneys don’t get an adequate blood supply, hypertension may worsen since the kidneys help regulate blood pressure. Narrowed vessels also make it easier for clots to form. If a clot blocks blood flow to the heart or brain, a heart attack or stroke can occur.
Hypertension is called the “silent killer” because it tends to do its damage quietly, without causing symptoms that might alert you to its presence. As a result, about 30 percent of Americans don’t even know that they have the disease, according to the American Heat Association. For thousands of people every year, the first sign of the condition is a heart attack or stroke. But it doesn’t have to be that way—high blood pressure is easy for doctors to detect and treat successfully. To avoid the deadly effects of hypertension, follow the three steps outlined here:
Step 1: Get your blood pressure checked
Unlike other diseases that cause pain, swelling or high fevers, high blood pressure probably won’t alert you to its presence. That’s why it’s so important to have your blood pressure checked periodically. The likelihood of having hypertension increases as you age, so it’s important to have your blood pressure checked on a regular basis.
The test used to measure blood pressure is simple and painless: A rubber cuff is wrapped around your upper arm and the cuff is inflated. A health professional reads your pressure on a gauge or column of mercury while using a stethoscope to listen to the sound of blood pumping through your arteries. In seconds it becomes evident how hard your heart has to work to pump the blood (see “What do those numbers mean?” sidebar).
Step 2: Change dangerous habits
While high blood pressure can’t be cured, it can be controlled by making certain changes in behavior and activities:
- Maintain a normal weight. Being overweight can contribute to high blood pressure because the heart has to work harder to pump blood through excess fatty tissue. In some cases, people who lose excess weight lower their blood pressure.
- Keep moving. Exercise will help you shed excess pounds by burning calories. In addition, some studies show that exercise itself can reduce blood pressure.
- Stop smoking. The nicotine in cigarettes causes blood pressure to rise and dramatically increases the risk of stroke. According to the American Heart Association, the benefits of quitting begin the day you give up cigarettes.
- Shake the salt habit. By causing the body to retain fluids, salt may contribute to high blood pressure. To reduce your salt intake, try using herbs and spices for seasoning. Avoid packaged snacks and processed meats, which are high in salt.
- Limit alcohol. Although one drink (an ounce and a half of hard liquor, four ounces of wine or 12 ounces of beer) a day doesn’t raise blood pressure, indulging in two or three drinks a day is associated with an elevated risk of hypertension.
Step 3: Take prescribed medications
When changes in lifestyle don’t lower blood pressure, doctors may prescribe one or more antihypertensive drugs. Some of these medications work by removing excess fluid and salt in the bloodstream, others open up narrowed blood vessels and still others prevent the smallest blood vessels (arterioles) from narrowing.
To be effective, any prescribed medication must be taken regularly. People who stop taking their medications because they “feel fine” may ultimately suffer from rebound phenomenon, in which their blood pressure returns to a higher level than before.
Hypertension is a killer, but it can be treated and controlled. Don’t be one of the many Americans who have this life-threatening condition but aren’t aware of it. Get your blood pressure checked regularly.