Systolic blood pressure – the top number – has long been known to predict the risk of heart attack or stroke. A 2019 study suggests that diastolic blood pressure — the bottom number — also contributes to this risk.
- Diastolic blood pressure contributes to the risk of heart attack or stroke just like systolic blood pressure.
- Patients with elevated diastolic blood pressure should be monitored regularly.
Worrying about high systolic blood pressure (the upper number of a blood pressure reading) is no longer enough. High diastolic blood pressure (the bottom number on a blood pressure reading) is also a marker of cardiovascular risk. This is demonstrated by a study conducted by Kaiser Permanente, published on July 18, 2019 in The New England Journal of Medicine.
A study based on 36 million blood pressure readings
This very large study comprising more than 36 million blood pressure readings from more than one million people opposes decades of research showing that systolic hypertension is most likely to cause adverse effects. This had led risk assessment tools as well as cardiology guidelines to focus on the higher (systolic) values, with some experts even going so far as to claim that the lower (diastolic) values may be “reasonably ignored“.
Kaiser Permanente researchers found that although systolic blood pressure has a greater effect, both systolic and diastolic pressures significantly affect the risk of heart attack or stroke.
Consider both types of blood pressure
“This research provides a large amount of data on a fundamental question and gives such a clear answer: in all cases, systolic and diastolic pressures are important”, emphasizes the author Principal Alexander C. Flint.
Systolic blood pressure measures how hard the heart pumps blood through the arteries, while diastolic pressure indicates the pressure exerted on the arteries when the heart is at rest between beats.
Regular pressure checks in people at high risk
Dr. Flint explains that the finding that the two components of blood pressure have similar effects on cardiovascular risk at the lower threshold of 130/80 justifies the recent changes to the American College of Cardiology and American Heart guidelines. Association, which advises more regular monitoring of blood pressure in high-risk patients with hypertension.
