*The association between lipoprotein(a) testing, lipid lowering therapy intensification, and low-density lipoprotein cholesterol goal attainment

Abstract

Funding

Novartis provided research funding.

Background/Synopsis

Elevated Lipoprotein(a) [Lp(a)] has a causal role in the development of atherosclerotic cardiovascular disease (ASCVD). While therapies targeting Lp(a) are in development, Lp(a) testing can help refine risk of ASCVD and help intensify lipid lowering therapy (LLT). The contemporary association between Lp(a) testing and LLT intensification is not well understood across large health systems.

Objective/Purpose

This study investigates the association between Lp(a) testing and Lp(a) levels with LLT intensification and LDL-C goal attainment.

Methods

Using Veterans Affairs electronic health record data, we performed a retrospective cohort study of veterans with lipid testing between January 1, 2017 to June 30, 2024. First, we compared a 2:1 propensity matched cohort of veterans with LDL-C and Lp(a) testing with those with LDL-C testing alone. Second, we compared veterans with normal vs. elevated Lp(a) level (defined as > 50 mg/dL). The primary outcome was LLT intensification (initiation or uptitration) within 12 months following lipid testing. Secondary outcomes included LDL-C testing and LDL-C goal attainment within 12 months (< 100 mg/dL for primary prevention and < 70 mg/dL for secondary prevention). Multivariable logistic regression models were adjusted for year of test, age, sex, race, ethnicity, diabetes mellitus type 2, hypertension, body mass index, ASCVD history, baseline LLT, baseline LDL-C, SVI, rurality, and cardiology visits in the prior year.

Results

Among 2,004,597 total eligible veterans with LDL-C testing, 10,386 (0.5%) had concurrent Lp(a) testing. The cohort included 2,562 Veterans with elevated Lp(a). The final study cohort included 20,768 propensity-matched patients (12.4% women and 19.2% of self-identified Black race; mean [SD] age, 58.4 [15.3] years) with a mean (SD) initial LDL-C of 110 [48.7]. In fully adjusted models, Lp(a) testing was associated with increased LLT intensification (OR [95%CI]: 2.11 [1.95 – 2.29]), increased LDL-C testing (OR [95%CI]: 1.27 [1.19 – 1.36]) and LDL-C goal attainment (OR [95%CI]: 1.22 [1.12 – 1.33]). In fully adjusted models, elevated Lp(a) was associated with increased LLT intensification (OR [95%CI]: 1.73 [1.55 – 1.94]) and similar LDL-C testing (OR [95%CI]: 0.99 [0.88 – 1.10]). There was not a significant association with LDL-C goal attainment (OR [95%CI]: 0.88 [0.76 – 1.02]) (Figure 1) overall, but there was lower LDL-C goal attainment among individuals with Lp(a) > 100 mg/dL (OR [95%CI]: 0.68 [0.56 – 0.84]).

Conclusions

Lp(a) testing was associated with increased LLT intensification and LDL-C goal attainment. Veterans found to have elevated Lp(a) were also more likely to undergo LLT intensification. Lp(a) testing may provide a valuable opportunity for motivating intensification of LLT and tracking of LDL-C towards goal attainment.