A recent study compared blood pressure, cholesterol levels, and the use of antihypertensive and lipid-lowering medications between individuals with obesity and those with normal body mass index (BMI) in industrialized countries.
Study
Blood pressure and cholesterol were analyzed among adults with obesity, overweight, and normal BMI across seven industrialized countries in Asia, Europe, and North America. These included Japan, South Korea, Taiwan, Thailand, Finland, England, and the United States.
The analysis included 110 nationally representative studies from 1990 to 2024, covering 978,425 adults aged 20 to 79 with measured height, weight, and at least one blood pressure or cholesterol value. Each study year was divided into up to 24 groups by sex, age, and BMI.
Outcomes measured included systolic blood pressure (SBP), non-HDL and HDL cholesterol, and the use of antihypertensive and lipid-lowering medicines. Results are reported for adults classified by sex, age group, and BMI category: Normal (20.0 to under 25.0), overweight (25.0 to under 30.0), class I obesity (30.0 to under 35.0), and class II/III obesity (35.0 and above).
Findings
Researchers found that although obesity became more common in all seven countries over the study period, with the largest increases in the USA and the lowest prevalence remaining in Japan and South Korea, the relationship between obesity and several key cardiovascular risk factors changed substantially over time. In particular, differences in non-HDL cholesterol and systolic blood pressure (SBP) between BMI groups became smaller, especially among older adults.
Among people with normal BMI, non-HDL cholesterol declined in England, Finland, and the USA, and among older adults in South Korea and Taiwan. In contrast, younger and middle-aged adults in most Asian countries experienced little change. HDL cholesterol generally increased in people with normal BMI, remaining stable only in Taiwan and rising more modestly in Finland and the USA.
A similar pattern emerged for blood pressure. SBP fell in most countries, particularly among older adults, with the largest reductions seen in Japan, South Korea, and England. Thailand was the exception, where SBP increased over time. However, declines in both non-HDL cholesterol and SBP were generally greater among people with overweight or obesity than among those with normal BMI, resulting in a narrowing of differences between BMI groups.
This convergence was most pronounced among older adults and those with severe obesity. By the end of the study period, older adults with severe obesity in England and the USA had lower non-HDL cholesterol than their normal-BMI counterparts, a pattern that was also observed in some Asian countries, except among females in Taiwan. Among middle-aged adults, the gap also narrowed, particularly in the higher obesity classes, although obesity continued to be associated with higher non-HDL cholesterol. In younger adults, by contrast, these differences changed little and in some cases became larger.
HDL cholesterol followed a different trajectory. Across all age groups, people with overweight or obesity consistently had lower HDL cholesterol than those with normal BMI, and this gap generally widened over time because HDL cholesterol increased more among people with normal BMI. Differences in SBP also narrowed in most countries, although Taiwan again was an exception, where the gap widened despite larger declines among females. By 2022, older adults with overweight or obesity in the USA had lower SBP than those with normal BMI. Overall, the link between BMI and both cholesterol and blood pressure weakened in older adults but remained strong in younger adults.
The researchers also found that these changing risk-factor patterns coincided with an increase in the use of preventive medications. Cholesterol-lowering medicines, which were rarely used before 2000, became increasingly common among older adults, particularly in South Korea, Thailand, England, and the USA, while Taiwan consistently had the lowest treatment rates.
Use also increased among middle-aged adults in South Korea but remained uncommon in younger adults. Throughout the study period, older and middle-aged adults with overweight or obesity were more likely to receive lipid-lowering therapy than those with normal BMI, and this difference widened over time, especially in England, the USA, and Thailand.
A similar trend was observed for antihypertensive treatment. Use increased among older adults with normal BMI in several Asian countries, particularly Thailand and South Korea, but changed little in the USA and among most middle-aged adults. Across countries, however, antihypertensive medicines were used most frequently by older and middle-aged adults with overweight or obesity, especially older males in England and the USA, while treatment remained uncommon among younger adults regardless of BMI.
Conclusion
Obesity rates rose in all countries, but gaps in cholesterol and blood pressure between BMI groups narrowed over time, especially among older adults. The authors suggest that increased use of cholesterol- and blood pressure-lowering medicines may have been an important contributor to these improvements, while noting that lifestyle and dietary changes are also likely to have played a role.
However, HDL cholesterol diverged, remaining lower and increasingly so among people with obesity, and differences in cardiometabolic risk remain, particularly among young adults with obesity, who were rarely treated regardless of BMI, highlighting the need for continued public health efforts focused on early prevention, screening, and treatment where appropriate.
Source:
https://www.news-medical.net/news/20260706/Thirty-years-of-data-reveal-changing-heart-health-trends-in-obesity.aspx