Follow-Up Lipid Testing and Statin Initiation Among Young Adults in a U.S. Health Care System.

Abstract

More than 50% of U.S. young adults have low-density lipoprotein cholesterol (LDL-C) ≥100 mg/dL, and young adults are less likely to be aware of their high LDL-C levels compared with older age adults. This study examined patterns of LDL-C testing and statin initiation following an initial elevated LDL-C measurement and assessed temporal trends of LDL-C testing and statin initiation from 2008 to 2018. We identified Kaiser Permanente Southern California members aged 18 to 39 years with their first elevated LDL-C measurement (index) between 2008 and 2020. We examined the proportion of young adults with a follow-up LDL-C test and statin initiation within 1, 2, and 5 years after the index LDL-C measurement, overall, and stratified by high-risk subgroups. We also assessed the temporal trends of follow-up LDL-C testing and statin initiation within 1 year of an elevated LDL-C measurement from 2008 to 2018 among high-risk subgroups: 1) LDL-C ≥190 mg/dL; and 2) LDL-C 160 to 189 mg/dL and high estimated 30-year atherosclerotic cardiovascular disease (ASCVD) risk. Among 771,681 young adults, 65.9%, 25.3%, 6.9%, and 1.9% had an index LDL-C of 100 to 129 mg/dL, 130 to 159 mg/dL, 160 to 189 mg/dL, and ≥190 mg/dL, respectively. Among those with LDL-C ≥190 mg/dL, 28.4%, 33.5%, and 45.7% initiated a statin within 1, 2, and 5 years, respectively. The proportions of young adults with 30-year high ASCVD risk and LDL-C ≥160 to 189 mg/dL who initiated a statin were 25.3%, 31.9%, and 46.4% within 1, 2 and 5 years, and 44.1%, 50.2%, and 61.5% within 1, 2, and 5 years, respectively, among those with LDL-C ≥190 mg/dL. Follow-up LDL-C testing within 1 year declined between 2008 and 2018, from 52.5% to 35.4% among those with LDL-C 160 to 189 mg/dL and high 30-year risk. Statin initiation within 1 year also declined in both high-risk subgroups from 31.7% and 36.5% in 2008 to 20.1% and 12.6% in 2018. These findings suggest care gaps in lipid management of young adults with elevated LDL-C and represent missed opportunities to reduce cumulative LDL-C exposure and to prevent premature ASCVD during a critical window of vulnerability.