A research letter published in JAMA Cardiology noted a reduction in the prevalence of elevated low-density lipoprotein cholesterol (LDL-C) between 1999 to 2000 and 2017 to 2020, although a considerable proportion are still unaware and untreated, according to a research letter. Ahmed Sayed, MBBS, and colleagues conducted a cross-sectional study using data from the National Health and Nutrition Examination Survey to identify adults in the US with LDL-C levels of 160 to 189 mg/dL and 190 mg/dL or greater from 1999 to 2000 and 2017 to 2020. The study included 23,667 participants, of whom 7.8% and 2.8% had an LDL-C level of 160 to 189 mg/dL and 190 mg/dL or greater, respectively. From 1999 to 2000 and 2017 to 2020, the age-adjusted prevalence of an LDL-C level of 160 to 189 mg/dL and 190 mg/dL or greater decreased from 12.4% to 6.1% and from 3.8% to 2.1%, respectively. Among those with an LDL-C level of 160 to 189 mg/dL, the fraction who were unaware and untreated decreased from 52.1% to 42.7% from 1999 to 2000 and 2017 to 2020, while that of those with an LDL-C level 190 mg/dL or greater decreased from 40.8% to 26.8%.