So how do you know if you really have high blood pressure?
First, make sure that the office reading is done correctly. "Readings should be taken only after you've been sitting or lying down for five or 10 minutes — not just after you've raced into the office," Brangman says.
It's also a good idea for your doctor to get a second reading after you stand up. (As you get older, the mechanism that increases blood pressure automatically when you get out of bed or a chair can become less responsive, making you prone to falls. This is a condition called orthostatic hypotension.)
If your office numbers are indeed high, ask your doctor about a home blood pressure monitor. These easy-to-use devices allow you to test your own blood pressure at various times during the day, which can help your doctor rule out both white coat hypertension and masked hypertension.
"Up until about 10 years ago, doctors only paid attention to diastolic hypertension. Now we know it's really systolic hypertension that matters in older people."
In some cases, doctors recommend ambulatory blood pressure testing, using a device that automatically takes readings of blood pressure over a 24-hour period. Ambulatory testing can identify people whose pressure doesn't fall during the night, as it should. This phenomenon, called "non-dipping," becomes more common as people age and has been shown to increase cardiovascular and stroke risk.
What should my numbers be?
High blood pressure in older people is very different from the condition in middle age.
"When people develop high blood pressure in middle age, the problem is typically elevated diastolic pressure, which is indicated by the lower number," says Izzo. Ideally, the goal is to bring the numbers down close to a normal reading of 120/80.
Once you hit age 60, though, it's the upper number — the systolic pressure — that can really climb, causing concern. Systolic hypertension occurs when the arteries close to the heart begin to stiffen, making them less responsive to blood flow.
"In a sense, you have almost two forms of hypertension," Logan says. "Up until about 10 years ago, doctors only paid attention to diastolic hypertension. Now we know it's really systolic hypertension that matters in older people."
Further, many older people develop a condition called wide pulse pressure, in which diastolic pressure drops even as systolic pressure climbs. The widening gap between the upper and lower numbers has been shown to be an independent risk factor for heart disease and stroke.
It also poses a tricky challenge for doctors. Drugs that lower systolic blood pressure typically bring down diastolic blood pressure, too. If that number is already low, medications can prove risky.