More than a billion people are now living with high blood pressure worldwide—most in low and middle-income countries, according to a new study led by Majid Ezzati, adjunct professor of global health at Harvard T.H. Chan School of Public Health. Published Nov. 15, 2016 in The Lancet, the study found that the number of people with high blood pressure has nearly doubled in the past 40 years, with the burden shifting to poorer countries—particularly in Asia, which was home to half of the world’s adults with high blood pressure in 2015. The United States, Canada, and South Korea had the lowest rates in the world.

“When you look at this globally, blood pressure is a condition of poverty, not affluence,” Ezzati, who also is a professor of global environmental health at Imperial College London, said in an interview with CNN. He attributed this trend to differences in healthy food options and access to health services.

Other Harvard Chan School researchers who contributed to the study include: Goodarz Danaei, Kaveh Hajifathalian, Yanping Li, the late Dimitrios Trichopoulos, Peter Ueda, and Damaskini Valvi.

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