A US government-supported study has found that high-density lipoprotein (HDL) cholesterol, known as the “good” or “good” cholesterol, may not be as predictive of cardiovascular disease risk among adults of different ethnic backgrounds as scientists once thought.
Cholesterol levels in general are important indicators of heart health, and for high-density lipoprotein (HDL) cholesterol, higher levels are better, according to the Mayo Clinic.
HDL cholesterol is known as the “good” cholesterol because it helps rid the bloodstream of other forms of cholesterol, and a higher level of cholesterol is associated with a lower risk of heart disease, and a lower level is associated with an increased risk.
The new study, supported by the US government’s National Institutes of Health, found that lower levels of HDL were associated with an increased risk of heart attack in white but not black adults, and it also found that higher levels were not associated with a lower risk of cardiovascular disease for either group.
“The goal was to understand this well-established link that makes HDL beneficial, and if this applies to all races,” said Natalie Pamir, lead author of the study and assistant professor in the Knight Heart and Vascular Institute at Oregon Health & Science University.
She added, “There was a belief that low levels of good cholesterol were harmful, regardless of race,” so this research was conducted to validate this assumption.
The previous studies that shaped perceptions of “good” cholesterol levels and heart health were conducted in the 1970s with research in which the majority of participants were white adults.
For the current study, the researchers were able to look at how cholesterol levels affected both middle-aged black and white adults without heart disease.
The researchers collected data from 23,901 adults from the United States who participated in a previous study over 11 years. The white and black participants had similar characteristics, such as age, cholesterol levels, and underlying risk factors for heart disease, including diabetes, high blood pressure or smoking.
The study found that lower levels of HDL cholesterol were associated with an increased risk of cardiovascular disease for white adults.
It also found that higher levels of “good” cholesterol were not always associated with lower levels of cardiovascular disease, meaning that optimal levels of “good” cholesterol were not necessarily good for the heart and blood vessels of either group.
“I hope that this type of research demonstrates the need to re-examine the risk prediction algorithm for cardiovascular disease,” the researcher said. “It may mean that in the future we will not be praised by our doctors for high HDL levels.”
Pamir said that while researchers study the role of HDL cholesterol in supporting heart health, they are exploring different theories to determine its role.
She says that its quality may be more important than its quantity in the body, that is, its ability to capture and remove excess cholesterol from the body.
Scientists are also analyzing hundreds of proteins involved in cholesterol transport and how different protein bindings, whether to a single protein or a group of proteins, can improve our ability to predict cardiovascular health.