Study links weight, blood pressure

The more overweight you are, the more likely you are to have high blood pressure, according to a study of 1.7 million Chinese men and women conducted by researchers at Yale University and in China.

The study participants’ blood pressure was measured from September 2014 to June 2017 as part of the China Patient-Centered Evaluative Assessment of Cardiac Events Million Persons Project, according to a news release. The project enables researchers to look at 22,000 subgroups based on age, sex, race and ethnicity, geography, occupation and other characteristics, including whether or not they are taking blood pressure medication. The subjects were age 35 to 80.

In looking at those whose blood pressure was not being treated, the researchers found that blood pressure increased 0.8 to 1.7 millimeters of mercury for every point increase in body mass index, which is a measure of body fat. The average BMI was 24.7 and the average systolic blood pressure (measured when the heart is beating and not at rest) was 136.5. Stage 1 hypertension is defined as a systolic blood pressure reading of 130 to 139, according to the American Heart Association. BMI of 25 and above is considered overweight for adults and 30 and above is considered obese, according to the Centers for Disease Control and Prevention.

A total of 39.8 percent of American adults, 93.3 million, were considered obese in 2015-16, and 32 percent of adults — 75 million — have high blood pressure, according to the CDC.

“The enormous size of the dataset — the result of an unprecedented effort in China — allows us to characterize this relationship between BMI and blood pressure across tens of thousands of subgroups, which simply would not be possible in a smaller study,” said George Linderman, first author and doctoral candidate at Yale, in the release.

One-third of Chinese adults have high blood pressure, the release said, obesity is expected to triple in men, from 4 percent in 2010 to 12.3 percent in 2025, and to double in women, from 5.2 percent to 10.8 percent. Only about 5 percent of Chinese have their blood pressure under control, the release said, according to an earlier Yale-CORE China paper for the Lancet based on data from the same project.

The study was published in the Aug. 17 issue of JAMA Network Open.