Reduce your risk of heart attack and stroke by aggressively decreasing your high systolic blood pressure (the top number). However, what significance does the diastolic (bottom) number have?
When it comes to blood pressure management, doctors typically focus on lowering the top (systolic) reading, and with good reason.
It has been proven that aggressively managing high systolic blood pressure will significantly reduce the risk of heart attack or stroke. However, what about the bottom number (diastolic)? It also plays a very important role in heart health, but one that is often overlooked.
A Tale of Two Digits
The two blood pressure readings indicate the heart's activity and rest. Systolic pressure is the pressure in the arteries caused by the contraction of the heart to pump blood throughout the body. The higher the number, the more difficult it is for the heart to pump blood.
Diastolic pressure refers to the pressure that exists between heartbeats. This pressure is necessary for coronary arteries to provide oxygen to the heart muscle. Normal blood pressure is defined as a systolic pressure of fewer than 120 millimetres of mercury (mm Hg) and a diastolic pressure of less than 80 mm Hg. A systolic value of 120 to 129 combined with a diastolic value of less than 80 is considered "elevated."
When it comes to diagnosing hypertension (high blood pressure), either number can be indicated if it is continually raised. For example, if your systolic blood pressure is 130 to 139 or your diastolic blood pressure is 80 to 89 — or both — you are said to have Stage 1 hypertension. Stage 2 hypertension is characterised by a systolic blood pressure of 140 or greater (or both) or diastolic blood pressure of 90 or greater. It's critical to monitor both numbers because, in several cases, if the systolic is elevated, the diastolic is elevated as well.
Deviation from the rules
There are, however, exceptions. While systolic pressure rises with age because blood vessels weaken and narrow, diastolic pressure goes down after the age of 50 because of this.
Why? With age, arteries become less elastic. When arteries become too stiff, they have a hard time coming back between heartbeats, which lowers diastolic blood pressure.
There could also be endothelial dysfunction, which is when the coronary arteries on the surface of the heart aren't able to expand as they should.
Additionally, isolated systolic hypertension is possible. This is a prevalent kind of hypertension in elderly people. Isolated systolic hypertension occurs when less elastic arteries have difficulty accepting blood surges. High-pressure blood flowing through these arteries can cause damage to their inner lining, hastening the accumulation of cholesterol-laden plaque. This makes the arteries even stiffer and narrower, which raises systolic blood pressure while keeping diastolic blood pressure the same.
Is diastolic pressure a cause for concern at any point in time? While lowering your blood pressure overall is beneficial, you do not want either number to fall too low. Systolic blood pressure that is too low raises the risk of weakness, lightheadedness, and fainting.
Surprisingly, a low diastolic value may indicate an increased risk of heart problems, according to a study published in JAMA Network Open on Feb. 1, 2021. This study enrolled individuals with a high risk of cardiovascular disease who were prescribed medication to reduce their systolic blood pressure.
The researchers discovered that those with a systolic blood pressure of less than 130 had a higher risk of heart attacks and strokes when their diastolic blood pressure was less than 60 mm Hg. Those with diastolic readings of between 70 and 80 mm Hg, on the other hand, had the lowest chance of developing heart disease.
For the majority of older people, the goal should be to maintain a systolic blood pressure of close to 120 mm Hg, or slightly lower, as long as the diastolic blood pressure remains at or above 60 mm Hg.
Lifestyle changes like cutting back on salt, increasing potassium, getting more exercise, and keeping a healthy weight are always the foundation of treatment, even if medication is also needed.
A less frequent complication is an elevated diastolic pressure with a normal or slightly higher top number. The treatment is the same in this case, with lifestyle changes first and blood pressure-lowering medications as needed.