By Mike Mwaniki
The number of adults aged 30–79 years with hypertension has increased from 650 million to 1.28 billion in the last 30 years, a new study recently published in The Lancet says.
The joint study—led by Imperial College London and the World Health Organisation—is the first comprehensive global analysis of trends in hypertension prevalence, detection, treatment and control which shows that nearly half of these people are unaware they had the disease.
According to experts, hypertension significantly increases the risk of heart, brain and kidney diseases, and is one of the top causes of death and disease throughout the world.
It can be easily detected through measuring blood pressure, at home or in a health centre, and can often be treated effectively with medications that are low cost.
The study, conducted by a global network of physicians and researchers, covered the period 1990–2019. It used blood pressure measurement and treatment data from over 100 million people aged 30–79 years in 184 countries, together covering 99 per cent of the global population, which makes it the most comprehensive review of global trends in hypertension to date.
By analysing this massive amount of data, the researchers found that there was little change in the overall rate of hypertension in the world from 1990 to 2019, but 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 per cent of people who have 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 ageing.
In 2019, over one billion people with hypertension (82 per cent of all people with hypertension in the world) lived in low- and middle- income countries. 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 per cent of women and 51per cent of men) were unaware of their condition because they were never diagnosed. The study also indicated that more than half of people (53 per cent of women and 62 per cent 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 were effective in bringing blood pressure to normal ranges, in fewer than 1 in 4 women and 1 in 5 men with hypertension. Imperial College London senior author of the study, Prof Majid Ezzati, notes: “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.” 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 per cent for women, and 20 per cent for men, in several countries in these regions, creating a massive global inequity in treatment. Kenya, for example, is ranked among the top 10 countries with the lowest hypertension treatment rate in 2019 with women and men rated at 21 per cent and 10 per cent of all women and men with high blood pressure respectively. A research fellow at Imperial College London, who led the analysis, Dr Bin Zhou, observes: “Although hypertension treatment and control rates have improved in most countries since 1990, there has been little change in much of sub-Saharan Africa and Pacific Island nations.”
At the same time, the recently l a u n c h e d “ W H O Gu i d e l i n e f o r the pharmacological treatment of hypertension in adults” provides new recommendations to help countries improve the management of hypertension treatment. The WHO’s Dr Taskeen Khan, 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.