Lipoprotein (a) variability in high cardiovascular risk individuals with hypertriglyceridemia and controlled LDL-C on statin therapy in REDUCE-IT.

Background

Although repeated testing of lipoprotein(a) [Lp(a)] is generally not recommended because of the genetically determined nature of concentrations, reports of significant intraindividual variability in serial assessments have challenged the single lifetime measurement framework.

Objective

To determine sources of Lp(a) variability among individuals with elevated triglyceride levels and well-controlled low-density lipoprotein cholesterol (LDL-C).

Methods

Using Lp(a) assessments at baseline, month 12, and month 24 from participants in the Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial (REDUCE-IT), we identified characteristics that could support repeated testing.

Results

Among 386 participants with baseline Lp(a) 50 to <70 mg/dL, 140 (36.3%) had at least 1 subsequent assessment ≥70 mg/dL, whereas among 630 participants with baseline Lp(a) ≥70 mg/dL, 133 (21.1%) had at least 1 subsequent assessment <70 mg/dL. Baseline Lp(a), sex (female vs male), race, and several other characteristics were related to variability.

Conclusion

Among individuals at high cardiovascular risk with hypertriglyceridemia and controlled LDL-C on statin therapy, considerable variability was observed over 24 months. These findings suggest multiple assessments may be warranted for Lp(a)-related risk stratification and, potentially, eligibility for Lp(a)-targeted treatments, particularly among individuals with relatively high concentrations or certain demographic and clinical characteristics.