Perhaps the best place to start is by talking about what the numbers mean. Doctors will use the term 130 over 85, written as 130/85. The rest of us call it the top number and bottom number.
So, what do the top number and bottom number actually represent?
The top number (130 in our case above) is called systolic blood pressure, and it measures the pressure inside the arteries as the heart pumps the blood around our body. The bottom number is called diastolic blood pressure and it reflects the pressure inside the arteries in between heart beats or pumps – so it’s lower.1
Is one number more important than the other? The short answer is, they’re both important.
For many years the bottom (diastolic) number was considered the most important in monitoring and managing blood pressure.2 But research during the 1990’s showed that the systolic number also matters.
Systolic blood pressure tends to rise with age and tends to be a better predictor of risk from cardiac events (e.g. stroke and heart attack) than the diastolic reading.2
As we age, our arteries become less elastic. Imagine a garden hose that is left in the sun for many years, and it begins to harden, it won’t expand and shrink as well as a new soft hose. With arteries, it’s not sun damage, but a build-up of cholesterol-laden plaque on the walls, stiffening and narrowing the space blood has to flow through. But because the same volume of blood must pass through a smaller area or ‘opening’, the systolic pressure tends to rise, while the diastolic pressure remains the same or gradually falls over time.
A third, related measure has also emerged in assessing cardiovascular risk – pulse pressure.2 Pulse pressure is simply the systolic minus the diastolic reading. So, in the case of our 130/85 example, the pulse pressure would be 130-85 = 45. But if the systolic number moved to 140 and diastolic stayed where it was, the pulse pressure would be 55. If that rises to over 60, it’s considered a greater risk for cardiovascular disease, especially for older adults.
In summary, both numbers matter. But what is most important is that you should monitor them, because they paint a clear picture of your cardiovascular health. And with affordable and easy to use blood pressure monitors, you can do it in the comfort of your own home. Check out the range of the world’s leading blood pressure monitors here, so you can keep track of your blood pressure fluctuations for your doctor to evaluate.
Always read & follow the instructions for use & health warnings. For people with high blood pressure. Consult your doctor to evaluate the readings. Check your device periodically for accuracy.