Blood vessels constantly under high volume and high pressure strain don't get a chance to recover.
"A third of the people who have strokes, it's directly attributable to their blood pressure spikes," said Dr. Thomas Horowitz of Good Samaritan Hospital.
An ideal reading would be 110 over 70. Hypertension patients may take medications, eat less salt, exercise and eat right. But doctors say they need to stay on top of their levels to make sure their efforts are working.
Blood pressure is dynamic, it changes throughout the day. To get an accurate reading, doctors say you have to take your blood pressure at different times during the day on different days and get an average. A new study at Good Samaritan Hospital found you get different readings on different devices.
"A person who has high blood pressure might appear to be under control on their medications when in fact they are not because their blood pressure measurement is being underestimated," said Dr. Robert Kloner of Good Samaritan Hospital.
Researchers measured the blood pressures of about 300 patients on both the old style mercury devices and the new automatic machines.
The director of Good Samaritan's Heart Institute says equipment with mercury is being slowly phased out so the automated devices will become more of the norm. In the study, the newer machines measured pressure two points lower on both the top and bottom number.
A reading of 117 over 78 would read 115 over 76, but on some it was way off.
"Some patients had a discrepancy of up to 10 to 15 millimeters of mercury," said
Dr. Kloner says doctors should check their automatic machines against the mercury devices, and patients should know their blood pressure may look better than it actually is.
Dr. Kloner says if you use a home monitoring device at home, it may be a good idea to bring it into your doctor's office and check to see if there's a difference.