Extreme ups and downs in systolic blood pressure may be just as deadly as having consistently high BP, according to a study.
Researchers from Intermountain Medical Center Heart Institute in the US found that patients with systolic blood pressure numbers that varied by as much as 30 or 40 between doctor visits over an extended period of time were more likely to die than those with less extreme variances in their BP.
The systolic blood pressure reading (the upper number) indicates how much pressure blood is exerting against the artery walls when the heart beats.
According to the American Heart Association, a normal systolic blood pressure is less than 120. High blood pressure is categorised as above 140.
"Blood pressure is one of those numbers we encourage people to keep track of, as it is one indicator of your heart health," said Brian Clements from Intermountain Medical Center Heart Institute.
"The takeaway from the study is, if you allow your blood pressure to be uncontrolled for any period of time, or notice big changes in your blood pressure between doctor visits, you increase your risk of stroke, heart attack, kidney or heart failure, or even death," said Clements, lead invesigator of the study.
The researchers examined visit-to-visit variability of systolic blood pressure in 10,903 patient records. The patients were required to have had seven blood pressure measurements between 2007 and 2011.
After the date of their seventh recorded systolic blood pressure measurement, the patients were followed for five years, with researchers looking at all causes of mortality.
"The call to action for patients as a result of this study is to do everything they can to control their blood pressure on a regular basis," said Clements.
"Eat healthy foods, exercise regularly, and if your doctor has prescribed you medications for your blood pressure, be sure and take them consistently. Because any time your blood pressure is out of control, you are at higher risk of injury or death," he said.