Association Between Lipoprotein(a) Testing, Lipid‐Lowering Therapy Intensification, and Low‐Density Lipoprotein Cholesterol Goal Attainment: Findings From the Veterans Affairs Health System

BACKGROUND: Lipoprotein(a) (Lp[a]) can refine atherosclerotic cardiovascular disease risk assessment and guide lipid-lowering therapy intensification (LLTI). However, the association between Lp(a) testing and LLTI across large health systems is not well characterized. METHODS: Using Veterans Affairs electronic health record data, we conducted a retrospective cohort study of veterans undergoing lipid testing from January 1, 2017, to June 30, 2024. We first compared a 1:1 propensity-matched cohort with concurrent low-density lipoprotein cholesterol (LDL-C) and Lp(a) testing with those with LDL-C testing alone. We then compared veterans with elevated versus nonelevated Lp(a) (>50 versus <50 mg/dL). The primary outcome was LLTI within 12 months, defined as therapy initiation, dose escalation, or addition of another lipid-lowering agent. LDL-C goal attainment (<100 mg/dL primary prevention; <70 mg/dL secondary prevention) was assessed within 12 months. Multivariable logistic regression adjusted for sociodemographic and clinical factors. RESULTS: Among 6 941 840 veterans with LDL-C testing, 10 384 (0.1%) underwent Lp(a) testing. The propensity-matched cohort included 20 768 veterans (mean±SD age, 58.4±15.3 years; 12.4% women; 19.2% Black individuals). Elevated Lp(a) (>50 mg/dL) was present in 25% (n=2562). Lp(a) testing was associated with greater LLTI (odds ratio [OR], 2.11 [95% CI, 1.95-2.29]), LDL-C testing (OR, 1.27 [95% CI, 1.19-1.36]), and LDL-C goal attainment (OR, 1.22 [95% CI, 1.12-1.33]). Compared with Lp(a) <50 mg/dL, Lp(a) >50 mg/dL was associated with increased LLTI (OR, 1.73 [95% CI, 1.55-1.94]). Lp(a) >100 mg/dL was associated with lower LDL-C goal attainment (OR, 0.68 [95% CI, 0.56-0.84]). CONCLUSIONS: Lp(a) testing was associated with increased LLTI and LDL-C goal attainment. Elevated Lp(a) identified individuals more likely to undergo LLTI, suggesting testing may motivate preventive treatment optimization.