Hypertension Doubles to More Than 1.1 Billion Worldwide

Megan Brooks

November 16, 2016

The number of adults around the world living with hypertension has nearly doubled since 1975, from 594 million to over 1.1 billion in 2015, a large study shows.

The largest increase in prevalence has been in low- and middle-income countries in South Asia and sub-Saharan Africa, while prevalence has dropped in high-income countries, such as the United States, the United Kingdom, and Canada, the study found. Blood pressure remains "persistently" high in central and eastern Europe.

The study was published online November 15 in The Lancet.

"High blood pressure is the leading risk factor for stroke and heart disease, and kills around 7.5 million people worldwide every year. Most of these deaths are experienced in the developing world," lead author Majid Ezzati, PhD, from the School of Public Health, Imperial College London, United Kingdom, said in a statement.

"Taken globally, high blood pressure is no longer a problem of the Western world or wealthy countries. It is a problem of the world’s poorest countries and people," Dr Ezzati noted.

The findings stem from a comprehensive analysis of worldwide trends in adult blood pressure between 1975 and 2015 by the Non-Communicable Disease (NCD) Risk Factor Collaboration. The group pooled data from 1479 population-based studies with more than 19 million men and women aged 18 years or older from 200 countries (covering more than 97% of the world’s adult population in 2015).

Among the key findings:

  • Canada, the United Kingdom, Australia, the United States, Peru, South Korea, and Singapore had the lowest proportion of adults living with raised blood pressure in 2015 (below or around 1 in 8 women and 1 in 5 men).

  • More than a third of men in several central and eastern European countries, including Croatia, Latvia, Lithuania, Hungary, and Slovenia, have high blood pressure, and about a third of women living in most countries in West Africa (eg, Niger, Chad, and Mali) have high blood pressure.

  • In 2015, over half (590 million) of adults with high blood pressure lived in East, Southeast, and South Asia, of whom 199 million lived in India and 226 million in China.

  • In 2015, systolic blood pressure levels were lowest in South Korea and Canada, at about 118 mmHg for men and 111 mmHg for women.

  • In 2015, average age-corrected systolic blood pressure levels were highest in central and eastern Europe (eg, Slovenia, Lithuania, Croatia), sub-Saharan Africa (eg, Niger, Malawi, Mozambique), central Asia (eg, Georgia, Mongolia, Armenia), and Oceania (eg, Palau, Vanuatu), reaching 138 mmHg for Slovenian men and 133 mmHg for Nigerian women.

  • Men had higher blood pressure than women in most world regions in 2015.

"Our results," said Dr Ezzati, "show that substantial reductions in blood pressure and prevalence are possible, as seen in high-income countries over the past 40 years."

The results also suggest that the World Health Organization target of reducing the prevalence of high blood pressure by 25% by 2025 is "unlikely to be achieved without effective policies that allow the poorest countries and people to have healthier diets — particularly reducing salt intake and making fruit and vegetables affordable — as well as improving detection and treatment with blood pressure lowering drugs," Dr Ezzati said.

It Takes a Village

In a linked Comment, Kazem Rahimi, MD, from The George Institute for Global Health, University of Oxford, United Kingdom, says one key insight from this analysis is that "substantial and continuous reductions in mean blood pressure and prevalence of raised blood pressure are achievable, as evident from the decreasing trends in the high-performing, mainly high-income, regions and countries."

"However, the opposing trends in several other, mainly low-income and middle-income countries, suggest that these countries are unlikely to achieve substantial reductions in mean age-standardized population-level blood pressure if no additional measures are taken," he writes.

While the past 30 years have led to improved medical care and greater use of antihypertensive treatments, these treatments "remain heavily underused in both rich and poor countries, calling for alternative models of healthcare delivery that are less dependent on healthcare professionals and instead make evidence more directly accessible to end-consumers," Dr Rahimi says.

"Effective control of raised blood pressure," he concludes, "requires collaborative, multisectoral, national efforts to improve implementation of available evidence. The failure to tackle this issue more decisively will come at a high cost, particularly to disadvantaged individuals and societies. The clear view of recent achievements, as provided by the NCD Risk Factor Collaboration, should help us to collectively steer the action plan more effectively and equitably towards decreasing blood pressure globally."

The study was funded by the Wellcome Trust. The authors have disclosed no relevant financial relationships.

Lancet. Published online November 15, 2016. Abstract, Comment

For more Medscape Neurology news, join us on Facebook and Twitter


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.