In a groundbreaking new study published in the Journal of the American College of Cardiology: Advances, researchers at the University of California San Diego School of Medicine have unveiled compelling evidence that testing for lipoprotein(a), commonly abbreviated as Lp(a), remains woefully uncommon across the United States. Despite the recognized importance of Lp(a) as a genetic marker for cardiovascular disease, large-scale adoption of testing has lagged considerably, with only modest increases over the past decade. This disparity underscores a critical gap in cardiovascular risk assessment, especially when juxtaposed with more aggressive testing practices seen in European countries.
Lipoprotein(a) is a complex cholesterol particle that circulates in the bloodstream, distinguished by its unique structural composition of an LDL-like particle bound to a specific protein called apolipoprotein(a). Elevated Lp(a) levels are causally linked to heightened risk of major cardiovascular events, including heart attacks, strokes, and aortic valve disease. Unlike more modifiable cholesterol fractions such as low-density lipoprotein (LDL), Lp(a) concentrations are primarily inherited and remain stable throughout a person’s lifetime. This intrinsic genetic basis means that lifestyle interventions largely fail to affect Lp(a) levels, making early identification through testing particularly crucial for preventative cardiology.
The UC San Diego research team leveraged the Epic Cosmos database, a vast repository aggregating over 300 million electronic health records across all 50 states, to assess national testing patterns for Lp(a) from 2015 to 2024. This unprecedented scale marks the largest epidemiologic evaluation of Lp(a) testing in U.S. history and sheds new light on how frequently individuals are screened for this genetic risk factor. Their analysis revealed that only 728,550 patients—corresponding to a mere 0.2% of the total U.S. population—had undergone Lp(a) testing during this period. Although testing rates have surged from roughly 14,000 in 2015 to over 300,000 in 2024, these figures remain significantly below expert recommendations.
The findings reveal a concerning disconnect between clinical guideline advocacy and real-world practice. While European health systems have moved towards universal screening protocols, largely recognizing Lp(a) as an early and potent predictor of cardiovascular risk, the United States continues to lag. According to lead author Dr. Mattheus Ramsis, an assistant professor at UC San Diego School of Medicine, the data serves as a stark reminder of “how much work remains to bring Lp(a) testing into routine care.” The study underscores the necessity for broader clinician education, systematic guideline implementation, and expanded insurance coverage to facilitate widespread adoption of this critical diagnostic test.
Delving deeper, the research uncovers distinct demographic and geographic disparities in Lp(a) testing patterns. Adults aged 50 to 65 were most frequently tested, suggesting some adherence to guideline recommendations targeting middle-aged populations at elevated cardiovascular risk. Testing rates between men and women were nearly equivalent, negating any evident sex-based bias. However, racial and ethnic disparities were striking: Black patients represented less than 10% of those tested, while Hispanic or Latino individuals accounted for only 7%, despite disproportionately bearing the burden of cardiovascular disease. Moreover, testing was predominantly concentrated among white patients, amplifying concerns about equity and access in preventive cardiology.
Geographic variations were equally notable, with the majority of testing concentrated in three states—California, Ohio, and Texas—accounting for over one-quarter of national tests. Conversely, several states reported negligible Lp(a) testing uptake, revealing a patchwork landscape of awareness and practice that may reflect differences in local clinical culture, practitioner education, or healthcare infrastructure. These disparities underscore the urgent need for national initiatives to standardize testing recommendations and amplify outreach, particularly in underserved or rural regions.
Technological evolution in testing methods also emerged as a key finding. In 2015, the majority of Lp(a) assays relied on older “mass-based” techniques, which quantify the total weight of lipoprotein particles in a blood sample but can be confounded by varying particle size and structure. Over time, laboratories have increasingly transitioned to molar-based assays, which count the number of Lp(a) particles directly, offering enhanced accuracy and better alignment with current clinical guidelines. By 2024, these molar assays constituted approximately two-thirds of all tests conducted, reflecting advances in diagnostic precision and standardization crucial for improved risk stratification.
From a pathophysiological perspective, Lp(a) differs markedly from other cholesterol particles because its levels are genetically preordained and scarcely influenced by environmental or lifestyle factors such as diet and exercise. Consequently, unlike LDL cholesterol—which can often be lowered by statins and other therapies—Lp(a) concentrations remain stubbornly elevated throughout life. Current therapeutic options specifically targeting Lp(a) are limited, but the horizon is promising: late-stage clinical trials for several novel pharmacologic agents designed to reduce Lp(a) levels are underway. The broader implementation of Lp(a) testing, therefore, is critical to identify candidates who may most benefit from these emerging therapies.
Despite the growing clinical recognition of Lp(a)’s role, testing remains a clinical afterthought for the vast majority of Americans. National guidelines advocate for at least one lifetime Lp(a) screening, particularly for individuals with a family history of premature cardiovascular disease or unexplained cardiovascular events at a young age. Yet, with fewer than one in 500 Americans currently receiving this evaluation annually, the UC San Diego team stresses the significant journey ahead to fulfill these recommendations and optimize cardiovascular risk management nationwide.
Dr. Ehtisham Mahmud, a cardiology professor and co-author on the study, emphasizes that improving testing rates is not solely a matter of clinical protocol but also of health equity. Populations disproportionately affected by cardiovascular disease, including minority and underserved communities, paradoxically receive fewer opportunities for this critical diagnostic evaluation. Closing such gaps requires comprehensive strategies incorporating education, healthcare policy reform, and insurance coverage expansion aimed at making Lp(a) testing accessible and routine for all demographics.
The team’s research transcends merely cataloging current testing trends; it is a call to action for the cardiology community and healthcare systems at large. Future investigations are planned to unravel the complex socio-economic and systemic barriers that impede equitable Lp(a) screening. Additionally, ongoing surveillance will monitor how testing patterns evolve as new Lp(a)-lowering therapies gain approval and enter clinical practice, potentially revolutionizing cardiovascular disease prevention and management.
The implications of these findings resonate broadly. Heart disease, the leading cause of death in the United States, demands innovative approaches in risk prediction and early intervention. Lipoprotein(a) testing offers a potent tool to identify high-risk individuals before catastrophic events occur. To realize this potential, substantial efforts must be invested in transforming clinical awareness into widespread, routine practice—ensuring that no patient is left behind in the fight against cardiovascular disease.
This pioneering study delineates a roadmap not only for improving Lp(a) testing rates but also for addressing entrenched disparities in cardiovascular health. By harnessing large-scale data, embracing technological advancements in testing, and advocating for equitable healthcare delivery, the U.S. can progress toward a future where preventive cardiology leverages genetics as a cornerstone of personalized medicine. The time to act is now, as emerging therapies beckon and the opportunity to redefine cardiovascular risk management is within reach.
Subject of Research: Lipoprotein(a) Testing in Cardiovascular Disease Risk Assessment
Article Title: Lipoprotein(a) Testing Remains Rare in the U.S. Despite Growing Recognition of Cardiovascular Risk
News Publication Date: September 26, 2025
Image Credits: Kyle Dykes / UC San Diego Health Sciences
Keywords: Heart disease, Cholesterol, Genetics
