In the past 40 years, there has been a large increase in the number of people living with high blood pressure (BP) worldwide because of population growth and ageing — rising from 594 million in 1975 to over 1.1 billion in 2015.
The largest rise in the prevalence of adults with high blood pressure has been in low- and middle-income countries (LMICs) in south Asia (e.g., Bangladesh and Nepal) and sub-Saharan Africa (e.g., Ethiopia and Malawi). But high-income countries (e.g., Australia, Canada, Germany, Sweden, and Japan) have made impressive reductions in the prevalence of adults with high blood pressure, according to the most comprehensive analysis of worldwide trends in blood pressure to date, published in The Lancet.
Both elevated systolic (higher than 140 mmHg; first number in blood pressure reading) and diastolic (higher than 90mmHg) blood pressure can be used to make a diagnosis of high blood pressure. Recent research suggests that the risk of death from ischemic heart disease and stroke doubles with every 20 mmHg systolic or 10 mmHg diastolic increase in middle and older ages.
The findings come from a comprehensive new analysis of global, regional, and national trends in adult (aged 18 and older) blood pressure between 1975 and 2015. This includes trends in average systolic (the maximum pressure the heart exerts while beating) and diastolic blood pressure (amount of pressure in the arteries between beats), as well as prevalence of high blood pressure.
The Non-Communicable Disease (NCD) Risk Factor Collaboration pooled data from 1479 population-based studies totalling 19.1 million men and women aged 18 years or older from 200 countries (covering more than 97% of the world’s adult population in 2015).
Key findings include:
* 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.