US Changes Definition for High Blood Pressure

From VOA Learning English, this is the Health & Lifestyle report.

Recently, two leading heart organizations changed the definition of what it means to have high blood pressure. Because of this change, the number of Americans with high blood pressure jumped from 32 percent to 46 percent.

Doctors at the American Heart Association and the American College of Cardiology now classify anyone with a blood pressure reading of 130 over 80 as having high blood pressure.

Before, the cutoffs for high blood pressure had been a top number of 140 and a lower number of 90.

Health experts at the website Science Daily say blood pressure is defined by two numbers. The top number, called systolic, represents the force with which your heart pumps blood into the blood vessels. The bottom, called diastolic, is a measure of the resistance to the blood flow in the body's blood vessels.

The American Heart Association says the new guidelines are designed to help people take steps to control their blood pressure earlier. High blood pressure can cause heart disease and stroke – the two leading causes of death in the world.

The new guidelines set blood pressures in these categories:

• Normal Blood Pressure: Under 120 over 80
• Elevated Blood Pressure: Top number 120-129 and bottom number less than 80
• High Blood Pressure / Stage 1: Top number of 130-139 or bottom number 80-89
• High Blood Pressure / Stage 2: Top number at least 140 or bottom number at least 90

High blood pressure around the world

A 2016 study by the World Health Organization and hundreds of scientists found that the number of people in the world with high blood pressure had reached 1.13 billion.

However, the study defined high blood pressure as 140 over 90. Should they adopt the new guidelines, the number of people with high blood pressure worldwide will most likely increase.

Scientists at Imperial College London led the study and looked at blood pressure measurements from nearly 20 million people from the years 1975 to 2015.

In this study, they found that the number of people with high blood pressure nearly doubled in 40 years.

Researchers found that over half of the world's adults with high blood pressure lived in Asia. Around 226 million people in China have high blood pressure, along with 200 million in India.

This study also found that in 2015 people in South Korea, the USA and Canada had the lowest high blood pressure rates in the world. With the new U.S. guidelines, the U.S. ranking in the world could change.

The researchers from Imperial College London published their findings from the study in the January 2017 edition of the medical journal The Lancet.

Does this mean more medication is necessary?

Health experts are warning people to not rush to medication to lower their high blood pressure. They advise that there are many lifestyle changes a person can make to effectively keep their blood pressure at a healthy level.

Regular exercise and losing weight can lower your blood pressure. In some people, making changes in diet can make a big difference. Eating more fruits, vegetables, fish, beans, nuts and seeds can help. Eating less sodium and drinking less alcohol can also help.

And that's the Health & Lifestyle report.

I'm Anna Matteo.

Anna Matteo wrote this report with information from the American Heart Association and Science Daily. Hai Do was the editor.

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Words in This Story

classify – v. to arrange (people or things) into groups based on ways that they are alike : to consider (someone or something) as belonging to a particular group

systole – n. the contraction of the heart by which the blood is forced onward and the circulation kept up : systolic – adj.

systolic blood pressure – medical noun the highest arterial blood pressure of a cardiac cycle occurring immediately after systole of the left ventricle of the heart — called also systolic pressure;

diastole – n. the dilatation of the cavities of the heart during which they fill with blood : diastolic – adj.

diastolic blood pressure – medical noun the lowest arterial blood pressure of a cardiac cycle occurring during diastole of the heart — called also diastolic pressure

resistance – n. a force that slows down a moving object (such as an airplane) by going against the direction in which the object is moving

category – n. a group of people or things that are similar in some way

edition – n. the form or version in which a text is published