Americans have made significant strides in the battle against high cholesterol; however, there are still widespread knowledge gaps, especially in underserved communities.
High cholesterol remains a prevalent issue in the United States and is a major contributor to cardiovascular disease (CVD). However, recent research indicates that adults are improving their cholesterol levels. Public health messaging about cholesterol also appears to be effective, as more adults are becoming aware of and seeking treatment for high cholesterol. Despite this progress, certain groups, including Hispanic, Black, undereducated, and low-income individuals, still lag behind.
A research letter published on November 1 in the medical journal JAMA Cardiology examined the relationship between high cholesterol, awareness, and treatment. The goal was to determine how many people with high cholesterol are aware of their condition and whether they seek treatment.
These questions are crucial because high cholesterol is a "silent" risk factor for more serious CVD in the future. It does not have identifiable symptoms, meaning individuals will not be aware of their condition unless they get their cholesterol levels checked.
The study utilized data from the National Health and Nutrition Examination Survey (NHANES), a program designed to assess the general health of Americans. Researchers analyzed approximately twenty years of participant data from 1999 to 2020, covering ten survey cycles. The study included 23,667 participants aged 20 and older.
Among this group, about 8% (1,851 participants) had clinically "high" LDL cholesterol (160-189 mg/dl), and about 3% (669 participants) had "very high" LDL cholesterol (190 mg/dl or greater). Researchers categorized individuals based on their knowledge of their condition. Those who had never undergone LDL cholesterol testing or were never informed of having high cholesterol were considered "unaware." Individuals who were never prescribed medication for high cholesterol, such as statins, were labeled as "untreated."
The percentage of individuals in the high range who were both unaware and untreated decreased from 52.1% to 42.7%. Similarly, the percentage of individuals in the very high range dropped from 40.8% to 26.8%.
Although the trend is moving in the right direction, these figures are still unacceptably high.
Dr. Salim Virani, one of the authors of the research letter and a Vice Provost and Professor at The Aga Khan University in Pakistan, as well as an Adjunct faculty at the Texas Heart Institute and Baylor College of Medicine, emphasized that awareness and treatment of very high levels of LDL cholesterol (bad cholesterol) remain very low in the United States.
There is both good news and bad news in the research letter. Let's start with the good news.
Over time, the study found a decline in the prevalence of severely elevated cholesterol, specifically LDL cholesterol, which is known to cause heart disease. This decline can be attributed to several factors, including increased awareness. According to Dr. Fatima Rodriguez, an Associate Professor of Medicine at Stanford University who is not affiliated with the research, this positive development is a result of greater awareness.
Between 1999 and 2020, the prevalence of clinical "high" cholesterol decreased from 12.4%, representing 21.5 million adults, to 6.1%, or 14 million people, after controlling for age.
Furthermore, the number of individuals with "very high" cholesterol decreased from 3.8% (6.6 million people) in 1999 to 2.1% (4.8 million people) in 2020.
What does this mean?
One in 17 US adults has high LDL cholesterol, and one in 48 has very high LDL cholesterol. Additionally, over 40% of individuals with high cholesterol are unaware of their condition and do not seek treatment. Furthermore, approximately one in four people with very high cholesterol are not aware of their condition and are not receiving treatment.