High blood cholesterol has increased in human populations in lower- and middle-income countries and declined in high-income countries since 1980, according to a paper published in Nature this week. The study, which examines data from more than 100 million individuals worldwide, reveals that changes in diet, behaviour and use of medication are driving one of the most important causes of heart disease around the world.
High blood cholesterol is a significant risk factor for heart disease and stroke, and has been considered a feature of high-income western countries. Previous studies have examined total cholesterol rates but have not analysed high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol separately, which are key markers for understanding cholesterol-related cardiovascular disease risk.
A group of nearly 1,000 researchers from around the world analysed data from 1,127 studies comprising 102.6 million adults to assess global trends in cholesterol levels from 1980 to 2018. The authors found that total and non-HDL cholesterol levels have increased in low- and middle-income countries, particularly in east and southeast Asia, and have declined in high-income western countries, especially northwestern Europe, and in central and eastern Europe. Belgium and Iceland saw some of the strongest decreases in non-HDL cholesterol since 1980. China, which had some of the lowest levels of non-HDL cholesterol in 1980, was among the highest in 2018. In 2017, non-HDL cholesterol was implicated as a contributing factor in 3.9 million deaths worldwide, half of which occurred in east, southeast and south Asia (compared to only a quarter in 1990).
The authors suggest that these results should motivate the use of policies that help replace saturated fats with unsaturated fats and to enhance treatment throughout the world.