What Changes in Hypertension Does 30 Years Show Us?

Medscape

October 2021

Clinical Context

Using the 2017 ACC/AHA guidelines, the US prevalence of hypertension has increased substantially to include approximately 46% of adults, but hypertension does not affect all racial and ethnic groups equally.

A review by Saeed and colleagues, which appeared on the American College of Cardiology website on April 6, 2020, examined this issue. Black adults have the highest rates of hypertension, and national research has found that adults of Hispanic and Asian descent have lower rates of hypertension compared with White adults; however, Saeed and colleagues note that research focused on regional communities has found that the rate of hypertension in Hispanic and Asian adults can exceed that of White adults.

Meanwhile, data from the Centers for Disease Control and Prevention found that, as of 2016, hypertension was controlled among 50.8% of White adults compared with 44.65% of Black adults, 45% of Hispanic adults, and 37.4% of Asian adults. The risk for mortality related to hypertension among Black adults is nearly twice that of White adults.

The current study by the Noncommunicable Disease Risk Factor Collaboration assesses the global epidemiology of hypertension.

Study Synopsis and Perspective

Over the past 3 decades, the number of adults around the world with hypertension increased from 650 million to 1.28 billion, and nearly half of these people do not know they have hypertension, according to the first comprehensive global analysis of trends in hypertension prevalence, detection, treatment, and control.

There is a “massive gap” in treatment, with a large percentage of people with hypertension who are not treated or even diagnosed, senior author Majid Ezzati, PhD, Imperial College London, told theheart.org | Medscape Cardiology.

“Where progress in treatment has been good, it has been a combination of general improvement in access to healthcare, through universal insurance and also basic availability of health centers and health workers; encouraging physicians/health workers to regularly measure blood pressure [(BP)] guidelines and training; and availability and affordability of medicines,” said Ezzati.

Uncontrolled Hypertension Prevalent

The analysis, led by researchers at Imperial College London and the World Health Organization (WHO), was published online August 24 in the Lancet and was presented August 30 at the European Society of Cardiology Congress 2021: The Digital Experience.

Ezzati and the Noncommunicable Disease Risk Factor Collaboration (NCD-RisC) analyzed data from 1201 population-representative studies, involving 104 million people from 184 countries, covering 99% of the world’s population.

Hypertension was defined as systolic blood pressure (SBP) ≥ 140 mm Hg, diastolic blood pressure (DBP) ≥ 90 mm Hg, or taking medication for high BP.

Globally, the number of adults aged 30 to 79 years with hypertension jumped from an estimated 331 million women and 317 million men in 1990 to 626 million women and 652 million men in 2019, with most of this increase happening in low- and middle-income countries.

The data show a “shifting of the issue from high-income countries, where rates of hypertension have declined, to low- and middle-income countries and central and eastern Europe, where rates have not changed much or gone up,” Ezzati told theheart.org | Medscape Cardiology.

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

Overall, in 2019, 41% of women and 51% of men with hypertension did not report a previous diagnosis, and 53% of women and 62% of men with hypertension were not receiving treatment.

Worldwide, high BP was controlled with medication in fewer than 1 in 4 women and 1 in 5 men. Men and women in Canada, Iceland, and South Korea were most likely to receive antihypertensive medication, with more than 70% of individuals with hypertension receiving treatment in 2019.

By contrast, men and women in sub-Saharan Africa, central, south, and south-east Asia, and Pacific Island nations were the least likely to be on medication. Treatment rates in a number of these regions were below 25% for women and 20% for men.

“Low detection and treatment rates that persist in the world’s poorest nations, coupled with the rising number of people who have hypertension, will shift an increasing share of the burden of vascular and kidney diseases to sub-Saharan Africa, Oceania, and south Asia,” coauthor Leanne Riley, from the WHO, said in a news release.

“Improving the capacity of these countries to detect and treat hypertension as part of primary healthcare and universal health coverage must be accelerated,” Riley added.

“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 [BP] in the world are still not getting the treatment they need,” Ezzati said.

Yet, some middle-income countries have successfully scaled up antihypertensive treatment, and are now achieving better treatment and control rates than most high-income nations. Costa Rica and Kazakhstan are 2 examples; both countries now have higher treatment rates than the majority of higher-income countries.

New WHO Guidelines

“There is an urgent need for a transformation and innovative approaches to reduce the burden of hypertension globally,” wrote Clara Chow, PhD, and Tu Nguyen, MD, PhD, from the University of Sydney, Sydney, Australia, in a linked comment.

“We need better strategies to increase diagnosis and management, leveraging primary care or existing systems or identifying new methods to engage consumers in [BP] management,” they said.

Given the “vast” differences in rates of hypertension prevalence, treatment, and control across countries, there is a need to examine local implementation, they added.

“From a medical model point of view, digital transformation such as telemonitoring, home [BP] monitoring, text message reminders to improve adherence, and other digital health interventions to encourage healthy behaviors, or simpler medical regimens such as initial treatment with a combination therapy — such as a single pill containing ultra-low-dose quadruple combination therapy — should be considered to address barriers to [BP] control,” Chow and Nguyen suggested.

“The standstill in global prevalence and the global control rates of approximately 20% should serve as an important global wakeup call that cardiovascular disease is going to be a main burden of disease for many years to come, especially if we carry on like this,” they concluded.

WHO also released new guidance for pharmacologic treatment of hypertension in adults to help countries improve the management of hypertension.

“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 with medicines for hypertension in adults,” Taskeen Khan, PhD, from the department of noncommunicable diseases at WHO, who led the guideline development, said in a news release.

The recommendations cover the level of BP to start medication, what type of medicine or combination of medicines to use, the target BP level, and how often to do follow-up BP checks.

“The need to better manage hypertension cannot be exaggerated. By following the recommendations in this new guideline, increasing and improving access to [BP] medication, identifying and treating comorbidities such as diabetes and pre-existing heart disease, promoting healthier diets and regular physical activity, and more strictly controlling tobacco products, countries will be able to save lives and reduce public health expenditures,” Bente Mikkelsen, PhD, director of WHO’s department of noncommunicable diseases, said in the release.

Study Highlights

• Researchers drew study data from databases from the NCD-RisC. They focused on studies that provided data on the prevalence of hypertension in a broad population in a country or region.
• The primary study outcomes were the prevalence of hypertension, the rate of participants reporting that history of hypertension (diagnosed hypertension), and the rates of hypertension treatment and control.
• Hypertension was defined as SBP ≥ 140 mm Hg, DBP > 89 mm Hg, or the use of antihypertensive medications.
• The current study focused solely on adults between the ages of 30 and 79 years.
• Researchers found a total of 1201 studies completed between 1990 and 2019, which included 104 million participants. The studies provided representative data from 99% of the global population.In 2019, the global prevalence of hypertension was 32% among women and 34% among men. These rates were similar to the 1990 estimates of global hypertension prevalence (32% among both women and men).
• The stable result over 3 decades was a result of a decrease in hypertension rates in high-income countries, with an increase in middle- and low-income countries.
• The nations with the lowest prevalence rates for hypertension in 2019 were Canada and Peru. Rates of hypertension among women specifically were lowest in Taiwan, South Korea, Japan, and some countries in western Europe.
• The prevalence of hypertension was highest in 2019 in central and eastern Europe, central Asia, Oceania, southern Africa, and some countries in Latin America and the Caribbean.
• 41% of women and 51% of men with hypertension did not report a previous diagnosis of hypertension.
• The treatment rate among adults with hypertension was 47% among women and 38% among men. Of those treated, the rates of hypertension control were 23% and 18%, respectively.
• Hypertension control rates were better in high- vs low-income countries. South Korea, Canada, and Iceland had the highest rates of hypertension control whereas Nepal, Indonesia, and several countries in sub-Saharan Africa featured hypertension control rates < 20%.
• Overall, rates of hypertension treatment and control improved from 1990 to 2019, but this effect was not noted in many countries in sub-Saharan Africa and Oceania.
• Hypertension control rates were lower among men vs women in most countries.
• Clinical Implications
• The prevalence of hypertension is highest among Black adults in the United States, and Black adults also have the highest rate of mortality related to hypertension.
• The global prevalence of hypertension remained stable between 1990 and 2019. Rates of hypertension fell in high-income countries but increased in middle- and low-income countries. Men had higher rates of uncontrolled hypertension compared with women.
• Implications for the healthcare team: The healthcare team should routinely evaluate adults for the presence of hypertension.

Cardiovascular Disease