Very High LDL Cholesterol Declines in US Adults, but Progress Is Slow

The prevalence of US adults with severely elevated LDL cholesterol has declined in the past two decades, as has the percentage of those who are unaware of their high cholesterol levels and who remain untreated, according to an analysis of the National Health and Nutrition Examination Survey (NHANES).

Despite the improvements, investigators say it’s not a “good news” story.

“If we call this progress, this is very slow progress over a period of 20 years, both in terms of the prevalence, but more importantly, in the areas of awareness and treatment among those with LDL-cholesterol levels of 160 to 189 mg/dL and those with LDL cholesterol ≥ 190 mg/dL,” senior investigator Salim S. Virani, MD, PhD (Aga Khan University, Karachi, Pakistan), told TCTMD.

More than 42% of people with LDL levels of 160 to 189 mg/dL were unaware of their high cholesterol and untreated in 2017-2020, which was down from 52.1% in 1999-2000. For those with LDL cholesterol levels of 190 mg/dL or greater, more than 26% were unaware of their hypercholesterolemia and untreated, down from 40.8% roughly two decades prior.

In patients with LDL-cholesterol levels this high, pharmacotherapy is indicated according to US guidelines, but awareness and treatment might be suboptimal given the unsatisfactory screening, say investigators. Led by Ahmed Sayed, MBBS (Ain Shams University, Cairo, Egypt), and published online November 1, 2023, in JAMA Cardiology, the study was designed to assess the prevalence, awareness, and treatment of those with elevated LDL cholesterol. Among 23,667 participants included from NHANES (1999 to 2020), 7.8% had LDL levels between 160 and 189 mg/dL and 2.8% had an LDL level of 190 mg/dL or greater.

From 1999-2000 to 2017-2020, the age-adjusted prevalence of people with LDL-cholesterol levels ranging from 160 to 189 mg/dL declined from 12.4% to 6.1%, while the prevalence of those with LDL levels of 190 mg/dL or higher declined from 3.8% to 2.1%.

Investigators point out that being unaware and untreated for severely elevated LDL cholesterol was more common in younger adults, men, Hispanic and non-Hispanic Black people (and other races/ethnicities), those with less income or education, and those without health insurance.

To close the treatment gaps, Virani said two things need to happen.

“First, we need to educate the general public about getting their cholesterol levels checked, and if high, then to ensure that their first-degree relatives get tested since some of these [cases] are genetic,” he said. “Second, clinicians need to be very well aware that they articulate the importance of screening and treatment of these individuals. Apart from diet and exercise, early treatment of those with LDL cholesterol ≥ 190 mg/dL is very crucial, as earlier the treatment starts, more the benefit.”

One concerning trend in their analysis, said Virani, is the number of young people with very high LDL levels who were in the dark about their cholesterol. When young, “this is precisely the time when these individuals need to be identified and treated,” he said.