The blood pressure cuff — that familiar low-tech tool — was introduced to the U.S. medical community in 1903. But don’t be fooled by its age and simplicity — it serves a critical function. “Let’s check your pressure” is often the first step in a medical visit.
A blood pressure reading gives two numbers, says Daniel Davies, D.O., of Beacon Internal Medicine, which is affiliated with Portsmouth Regional Hospital and HCA Health Care. They are expressed with the higher number over the lower, for example, 120 over 84 or 120/84. The first number is the systolic pressure, which measures the strength of blood flow when the heart contracts, pushing blood out into the arteries. The lower number is the diastolic pressure, which measures blood flow when the heart is relaxing and filling with blood.
The guidelines for classifying blood pressure ranges were revised in 2003 — normal blood pressure is now defined as 120/84 or less. Systolic pressure in a range of 121 to 139 indicates pre-hypertension. Systolic pressure of 140 or higher indicates hypertension or “high blood pressure.” The systolic number is more important than the diastolic in assessing the risk of heart disease. The goal of treatment is to lower the systolic pressure.
While most people have fairly consistent numbers, blood pressure does respond to both internal and external conditions. Elevated pressure during a stressful time or after hard physical exercise is not unusual. The American Heart Association uses the term “white coat hypertension” to describe those who find medical visits stressful enough to raise the blood pressure. The association suggests three readings to give a reliable assessment.
What do the numbers tell you? All levels of blood pressure put mechanical stress on arterial walls. The reading gives a numerical expression of the amount of that stress. A high pressure increases the heart’s workload and the progression of unhealthy tissue growth within the walls of arteries.
Dr. Davies explains that persistent hypertension is a risk factor for stroke, heart failure, heart attack, peripheral artery disease and arterial aneurysm. It is a leading cause of chronic renal failure. Reduction of elevated blood pressure will reduce the risk of these problems. “Hypertension is a chronic disease,” he says. “With few exceptions, we don’t know what causes it and we are not able to cure it. We can, however, control or manage hypertension.”
If one’s pressure is a little over the desired range, lifestyle changes may be sufficient to reduce the pressure. Recommended steps will likely include weight loss (if one is overweight), smoking secession, increased physical activity and reduced sodium intake. Many physicians will suggest a diet of fruits and vegetables, chicken, fish and low-fat dairy products. Regular practice of meditation or another relaxation technique is beneficial to some patients.
For most patients, however, medication will be prescribed. Diuretics remain a mainstay of hypertension management, often in combination with another medication. There are many choices of medication for hypertension, says Davies. If one isn’t getting the desired results, another medication will be tried. Generally these medications are well tolerated, but there is potential for side effects with any medication. Patients should note any unusual feelings or reactions.
An estimated 50 million Americans have high blood pressure, says Davies, but at least 30 percent are unaware of the condition and the risks involved. There are no symptoms that would alert a person to have it checked. Someone who is not involved in treatment for another condition and does not have an annual check-up may not discover hypertension until damage has been done.
Nancy Smith, of Keene, was unaware of having high blood pressure. It was diagnosed around the time she turned 70. “I guess getting older brought about the change,” she said. She takes Atenolol and hydrochlorothiazide and participates in a twice-weekly exercise program. “It hasn’t been a problem,” she says, “and my pressure is down to the normal range.”
Blood pressure usually does increase as one ages. A person with normal pressure at age 55 has a 90 percent possibility of developing high blood pressure over the years of his or her lifetime. Given that the U.S. population is aging, the incidence of hypertension is almost certain to rise. This trend will be accelerated by other health trends, specifically increased obesity, inactive lifestyle and the younger onset of diabetes.
“Let me again stress that hypertension or high blood pressure has no symptoms,” says Davies. “Yet it is common and can lead to significant health problems. Have your pressure checked regularly and know your numbers, especially if you are over 50.”
Some people use the pressure cuffs at pharmacies. This can be helpful. But many people, he says, forget their numbers or don’t bother letting the doctor know when pressure increases.
With the holiday season just ahead, he adds, think about how you might keep stress levels low. Limit alcohol to no more than two drinks per day (men) or one drink per day (women). Leave time for exercise in your busy schedule. Enjoy the holiday treats, but with moderation. NH
This article appears in the March 2010 issue of New Hampshire Magazine