Array of Drugs Tames Hypertension

by Food and Drug Administration (FDA)

The "silent killer" — hypertension, or high blood pressure — snuck up on my mother when she was in her 40s, making its presence known by causing congestive heart failure and resulting in several lengthy hospital stays.

Though her blood pressure measured as high as 250/150 during those initial touch-and-go days, she's maintained a much-closer-to-normal blood pressure for the past 30 years, thanks to daily doses of antihypertensive drugs.

Today's range of drugs for treating high blood pressure makes it possible for people like my mother and the nearly 50 million other Americans who suffer from high blood pressure to lead normal, healthy lives well into their senior years. Exercise, regular blood pressure checks, healthy eating, maintenance of a healthy body weight, and other lifestyle changes can make a big difference, too.

Without these treatments, people with consistently high blood pressure face increased risks for heart attack, stroke and kidney disease. High blood pressure also can cause blood vessels on the eye's retina to clog, eventually bursting and possibly damaging parts of the retina and impairing vision.

What Is Blood Pressure?

Blood pressure is the force of blood against the blood vessel wall. High blood pressure occurs when there is increased tension or pressure in the arteries. The greater the pressure, the harder the heart has to work.

Blood pressure is measured with a device called a sphygmomanometer, which can be either manual or electronic. The blood pressure reading is written as a fraction: for example, 120/80.

The first number is the systolic pressure, which is the point at which the heart contracts to push the blood out to the rest of the body. When blood pressure is taken manually, this is the number at which a person taking the blood pressure first hears a pulse through the stethoscope. When an electronic device is used, the number appears on the display.

The second number is called the diastolic pressure, which represents the lowest point in the pressure of blood — right before another squirt of blood enters the arteries. When the blood pressure is measured manually, this number is the point at which the person listening through the stethoscope stops hearing a pulse. On an electronic device, this number also automatically appears on the display.

Many people think that 120/80 is the perfect or normal blood pressure. But, says Robert Fenichel, M.D., deputy director of FDA's division of cardiovascular and renal drug products, "If your pressure is lower than that, good for you."

Deciding What's High

Elevated blood pressure rarely makes itself known; it usually has no symptoms. That's why it's often referred to as the silent killer. Feeling nervous or tense, for example, doesn't necessarily translate into elevated blood pressure. Getting periodic blood pressure checks is the only way to catch high blood pressure early.

According to the National Heart, Lung, and Blood Institute of the National Institutes of Health, a blood pressure reading consistently higher than 140/90 is a sign that the blood pressure needs to be brought under control.

Most doctors don't diagnose a person with high blood pressure on the basis of only one reading. People who find a visit to the doctor's office unnerving can have "white-coat hypertension," blood pressure that is only high when taken in the doctor's office. ("White coat" refers to the ubiquitous white lab coats many health professionals wear.) Others may have "labile hypertension," blood pressure that gets slightly elevated in certain situations but which is normal most of the time.

To rule these out, doctors may take a patient's blood pressure later during the office visit and ask the patient to come back for two more visits, taking two readings during each of those visits. Many doctors also ask patients with elevated blood pressure to have their blood pressure checked in a setting other than a medical one. With one of the many electronic blood pressure measuring devices that consumers can buy without a doctor's prescription, patients often can check and record their blood pressure at home. To get as accurate a reading as possible, the doctor may ask the patient to bring the device in to the office to make sure it is calibrated properly. This can usually be done by comparing the device's readings with readings taken at the same time with the doctor's blood pressure equipment.

If a patient has consistently high readings in and out of the medical setting, the doctor will decide what type of treatment is appropriate: diet modification, increased exercise, medicine, or a combination of these.

Treating Hypertension

Treatment can vary with the level of elevation of the blood pressure, as well as the patient's age and health. (See "Treating High Blood Pressure.") According to FDA's Fenichel, sometimes lifestyle changes can reduce blood pressure by 5 points or so. They include stopping smoking, reducing alcohol intake, losing excess weight, and making certain dietary changes, such as reducing sodium intake and possibly increasing potassium, calcium and magnesium intake. Some experts also recommend exercise and relaxation techniques, such as meditation.

"But," Fenichel says, "treatment with drugs is the only effective approach for attaining larger reductions in blood pressure."

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.