Abstract Body (Do not enter title and authors here): Background: Young adult women with severe hyperlipidemia (sHLD), or low-density lipoprotein cholesterol (LDL-C) ≥190 mg/dL, are less likely to achieve guideline-recommended LDL-C reduction than their male or older counterparts. Lipoprotein(a) [Lp(a)] can serve as a risk modifier of cardiovascular disease and may have some utility in risk-stratification in young populations.

Question: Do LDL-C control and Lp(a) testing differ by race among young adult women?

Methods: We used clinical registry data from seven Mass General Brigham hospitals/affiliated practices to identify young women (18-45 years) between 2005-2022 with a qualifying LDL-C ≥190 mg/dL. We used linear mixed models to assess longitudinal differences in LDL-C levels by self-identified race. We compared Lp(a) testing and statin initiation rates of these groups and examined whether LDL-C control differed according to Lp(a) testing.

Results: Our study included 4,633 women with sHLD, mean (SD) age 35.7 (7.0) years at qualifying LDL-C and median (IQR) follow up 5.8 (9.4) years. Compared to White women, Black women had persistently higher LDL-C levels during follow-up (coefficient=6.4, p<0.001), and women who reported other/multiple racial categories (Other) had a non-significant trend of persistently higher LDL-C during follow-up (coefficient=2.8, p=0.08) [Figure]. Overall, 255 (5.7%) women recieved Lp(a) testing. Lp(a) testing was positively associated with 50% LDL-C reduction (p<0.001), and 8.8% Asian, 3.8% Black, 4.9% Other and 5.9% White women underwent Lp(a) testing (p=0.04). Mean (SD) age of statin initiation was 39.9 (8.2) years; 51.9% Asian, 65.6% Black, 59.3% Other and 56.2% White women received a statin prescription during follow-up (p<0.001).

Conclusions: Young women with sHLD had persistently high LDL-C levels over time, and Black women experienced the highest LDL-C burden. Lp(a) testing was also low across all groups, with the lowest testing rates occurring in Black and Other populations, but was associated with improved LDL-C control. Statin initiation was low across all groups. These data highlight an urgent need for strategies to improve guideline-recommended preventive care in young women at high lifetime risk of cardiovascular disease.