Factors Associated with Lipoprotein(a) Testing Among Multiethnic Individuals

Area of Science:

• Cardiovascular Medicine
• Clinical Epidemiology
• Health Services Research

Background:

• Lipoprotein(a) [Lp(a)] is a recognized causal risk factor for atherosclerotic cardiovascular disease (ASCVD).
• Clinical guidelines advocate for the integration of Lp(a) testing into routine patient care.
• Understanding current Lp(a) testing patterns is crucial for addressing ASCVD risk.

Purpose of the Study:

• To investigate real-world, contemporary clinical testing patterns for Lp(a).
• To examine Lp(a) testing prevalence across diverse, multiethnic populations.
• To identify factors associated with Lp(a) testing utilization.

Main Methods:

• A nested case-control study was conducted within a large Northern Californian health system (2010-2021).
• Incident density matching was employed to select controls for cases (up to 1:5 ratio).
• Conditional logistic regression analyzed associations between Lp(a) testing and patient characteristics.

Main Results:

• Only 1.0% of 1,484,410 individuals underwent Lp(a) testing; median level was 35 mg/dL.
• South Asian individuals showed higher testing likelihood (OR=3.19), while Black and Hispanic individuals had lower rates.
• History of ASCVD (OR=2.14) and frequent primary care visits (OR=1.99) were associated with increased testing.

Conclusions:

• Real-world Lp(a) testing rates are low, with notable disparities based on race, ethnicity, and healthcare utilization.
• Expanding access to Lp(a) testing is essential for equitable ASCVD risk assessment and treatment.
• Addressing testing disparities will be vital as novel Lp(a)-targeted therapies emerge.