Study Casts Doubt on Protective Role of Good Cholesterol
It’s unlikely that HDL cholesterol is an independent risk factor for heart disease.
It’s unlikely that good cholesterol has a direct impact on heart health, according to a recent study that found a strong correlation between high-density lipoprotein cholesterol levels and other factors that influence cardiovascular risk.
Published in the Journal of the American College of Cardiology, this study explored the protective effects of good cholesterol on heart health. High-density lipoprotein cholesterol (HDL), often referred to as good cholesterol, helps remove bad cholesterol from the arteries. With HDL consistently linked to better outcomes and lower risk for heart disease, experts continue to wonder: Should we try to actively raise HDL to improve cardiovascular health? But so far, findings have been disappointing, and whether HDL is a direct risk factor for heart disease remains unclear.
To learn more, researchers analyzed a large dataset, which included health information on nearly 632,000 adults in Ontario, Canada. Known as the CANEHEART cohort, this study collected data on participants’ cholesterol, health and lifestyle, and tracked key outcomes, such as heart attack and death. The mean age of participants was 57, and more than half of them were women.
After following participants for roughly five years, there were a total of 17,952 deaths. Not surprisingly, lower HDL levels were associated with higher risk of heart disease, cancer and death than those with average HDL levels, defined as 41–50 mg/dl for men and 51–60 mg/dl in women. Researchers also noted that especially high HDL levels (greater than 70 mg/dl in men and greater than 90 mg/dl in women) were associated with increased risk of non-heart related death.
The problem was that HDL was also strongly correlated with other key factors, such as income, lifestyle and overall health. For example, participants with lower HDL levels were more likely to have lower incomes, unhealthy lifestyles, higher triglycerides, and other medical problems.
As a result, authors believe it’s unlikely that HDL is an independent risk factor for heart disease. Rather, they argue that there’s a complex association between HDL, health, lifestyle, and sociodemographic factors, which together impact overall health. Targeting other predictors of health is more likely to have an impact on outcomes, rather than raising HDL levels alone.
Questions for You to Consider
- What are the risks associated with high cholesterol?
- High cholesterol can cause atherosclerosis, the build-up of plaque on artery walls. This accumulation of deposits can cause serious complications, such as chest pain, heart attack and stroke. High cholesterol is largely preventable and treatable, so getting screened and making healthy lifestyle choices can go a long way in controlling cholesterol levels.
- At what age should I worry about my cholesterol?
- More than one-third of Americans have high cholesterol and risk for high cholesterol increases with age. However, high cholesterol can be a problem at any age. It’s estimated that 22% of adults in their 20s have high cholesterol and 62% of adults in their 50s have high cholesterol. It’s important to have cholesterol checked regularly and make healthy lifestyle choices like eating healthy and staying active, which help control cholesterol levels.