Over 700 million people living with untreated hypertension, says WHO

25 Aug 2021 --- The number of adults aged 30 to 79 years with hypertension has increased from 650 million to 1.28 billion in the last thirty years. The figures are according to the first comprehensive global analysis of trends in hypertension prevalence, detection, treatment and control, led by the World Health Organization (WHO) and Imperial College London. Nearly half these people did not know they had hypertension.

Hypertension significantly increases the risk of heart, brain and kidney diseases and is one of the top causes of death and illness worldwide. It can be easily detected through measuring blood pressure, at home or in a health center and can often be treated effectively with low-cost medications.

The study, conducted by a global network of physicians and researchers, covered the period 1990 to 2019. It used blood pressure measurement and treatment data from over 100 million people aged 30 to 79 years in 184 countries, covering 99 percent of the global population, making it the most comprehensive review of global trends in hypertension.

The findings have been published in The Lancet.Hypertension significantly increases the risk of heart, brain and kidney diseases and is one of the top causes of death and illness worldwide.

“Little change” in overall hypertension rate
By analyzing this amount of data, researchers found little change in the overall rate of hypertension globally from 1990 to 2019. Still, the burden has shifted from wealthy nations to low- and middle-income countries.

The rate of hypertension has decreased in wealthy countries – which now typically have some of the lowest rates – but has increased in many low- or middle-income countries.

As a result, Canada, Peru and Switzerland had among the lowest prevalence of hypertension in the world in 2019, while some of the highest rates were seen in the Dominican Republic, Jamaica and Paraguay for women and Hungary, Paraguay and Poland for men.

Although the percentage of people with hypertension has changed little since 1990, the number of people with hypertension doubled to 1.28 billion. This was primarily due to population growth and aging. In 2019, over one billion people with hypertension (82 percent of all people with hypertension in the world) lived in low- and middle-income countries.

“Significant gaps”
Although it is straightforward to diagnose hypertension and relatively easy to treat the condition with low-cost drugs, the study revealed significant gaps in diagnosis and treatment. About 580 million people with hypertension (41 percent of women and 51 percent of men) were unaware of their condition because they were never diagnosed.

The study also indicated that more than half of people (53 percent of women and 62 percent of men) with hypertension, or a total of 720 million people, were not receiving the treatment that they need.

Blood pressure was controlled, which means medicines effectively brought blood pressure to normal ranges in fewer than one in four women and one in five men with hypertension.Canada, Peru and Switzerland had the lowest prevalence of hypertension in the world in 2019.

“Nearly half a century after we started treating hypertension, which is easy to diagnose and treat with low-cost medicines, it is a public health failure that so many of the people with high blood pressure in the world are still not getting the treatment they need,” says Professor Majid Ezzati, senior author of the study and professor of Global Environmental Health at the School of Public Health at Imperial College London.

Men and women in Canada, Iceland and the Republic of Korea were most likely to receive medication to effectively treat and control their hypertension, with more than 70 percent of those with hypertension receiving treatment in 2019.

Comparatively, men and women in sub-Saharan Africa, central, south and south-east Asia, and Pacific Island nations are the least likely to be receiving medication. Treatment rates were below 25 percent for women, and 20 percent for men, in several countries in these regions, creating a massive global inequity in treatment.

Encouragingly, some middle-income countries have successfully scaled up treatment and are now achieving better treatment and control rates than most high-income nations. For example, Costa Rica and Kazakhstan now have higher treatment rates than most higher-income countries.

New guidance for hypertension treatment
The “WHO Guideline for the pharmacological treatment of hypertension in adults” provides new recommendations to help countries improve the management of hypertension.

Dr. Taskeen Khan, of WHO’s Department of Noncommunicable Diseases, who led the guideline development, says: “The new global guideline on the treatment of hypertension, the first in 20 years, provides the most current and relevant evidence-based guidance on the initiation of medicines for hypertension in adults.”

The recommendations detail the blood pressure level at which to start medication, what type of medicine or combination of drugs to use, the target blood pressure level, and how often patients must have follow-up checks on blood pressure.

In addition, the guideline provides the basis for how physicians and other health workers can contribute to improving hypertension detection and management.

Edited by Elizabeth Green