Ancestry, Lipoprotein(a), and Cardiovascular Risk Thresholds: JACC Review Topic of the Week

Lipoprotein(a) - From Biomarker to Therapy: A Review for the Clinician

Cardiovascular disease (CVD) remains the predominant cause of morbidity and mortality globally. Amid rising CVD rates, Lipoprotein(a) [Lp(a)] has been recognized as a critical biomarker identifying individuals at an increased risk of atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valve stenosis (AS), independent of traditional risk factors. Lp(a) is a lipoprotein variant similar to LDL but includes apolipoprotein(a), which influences its pathogenic potential. Elevated Lp(a) levels are genetically determined and have been implicated in promoting vascular inflammation, atherogenesis, enhanced calcification, and thrombosis. Emerging antisense oligonucleotide (ASO)- and small interfering ribonucleic acids (siRNAs)- based therapies have been shown to lower Lp(a) concentrations, with ongoing trials underway to determine whether they reduce the risk of CVD. While guidelines on screening and management continue to evolve, the advent of specific Lp(a)-lowering therapies may transform CVD prevention and treatment. This review aims to consolidate the current knowledge on Lp(a) from its biological functions to its implications for clinical practice, focusing on its role as a biomarker and potential therapeutic target.

Molecular Therapeutics in Development to Treat Hyperlipoproteinemia

Clinical endpoints caused by hyperlipoproteinemia include atherosclerotic cardiovascular disease and acute pancreatitis. Emerging lipid-lowering therapies targeting proprotein convertase subtilisin/kexin 9 (PCSK9), lipoprotein(a), apolipoprotein C-III, and angiopoietin-like protein 3 represent promising advances in the management of patients with hyperlipoproteinemia. These therapies offer novel approaches for lowering pathogenic lipid and lipoprotein species, particularly in patients with serious perturbations who are not adequately controlled with conventional treatments or who are unable to tolerate them. Molecular targets for these novel therapeutic agents were identified and validated through genetic epidemiology studies. Proprotein convertase subtilisin/kexin 9 inhibitors (e.g., monoclonal antibodies and small interfering RNA) have revolutionized hypercholesterolemia management by significantly reducing both low-density lipoprotein cholesterol levels and major cardiovascular events. Genome editing of PCSK9 promises to provide a potential cure for patients with familial hypercholesterolemia. Several investigational lipoprotein(a)-targeting therapies aim to reduce the risk of atherosclerotic cardiovascular disease and aortic valve disease, although definitive clinical endpoint studies remain to be completed. Inhibition of APOC3 messenger RNA expression by olezarsen and plozasiran significantly lowers plasma triglyceride levels and markedly reduces pancreatitis risk in patients with familial chylomicronemia syndrome. Finally, angiopoietin-like protein 3 inhibition by the monoclonal antibody evinacumab has transformed management of patients with homozygous familial hypercholesterolemia. Together, these novel agents expand the therapeutic cache, offering personalized lipid-lowering strategies for high-risk patients with hyperlipoproteinemia, improving clinical outcomes and addressing previously unmet medical needs.

Lipoprotein(a) and Its Association with Coronary Heart Disease: Data from a Large Cohort in the Russian

Aim      To study the distribution of lipoprotein(a) [Lp(a)] concentrations in a large sample of the adult population of the Russian Federation depending on gender and age, and the Lp(a) association with the incidence of ischemic heart disease (IHD).Material and methods  Cross-analysis of electronic medical records of patients older than 18 years managed in the MEDSI Group of Companies as a part of primary and secondary prevention.Results Among 73,763 patients, the mean age was 45 [37; 56] years, 57.3% were women. The median Lp(a) concentration was 11 [6.0; 32.0] mg/dl. The median Lp(a) concentration in women was higher than in men, 12.0 and 10.5 mg/dl, respectively (p<0.0001). Hyperlipoproteinemia(a) (Lp(a) >30 mg/dl) was diagnosed in 26% (n=19,188) of patients (95% confidence interval (CI): 25.7-26.3), statistically significant association with IHD was observed over the entire range of elevated Lp(a) concentrations (p<0.001). Extremely high Lp(a) concentrations exceeding 180 mg/dl were detected in 852 (1.2%) of patients, and 210 of them were diagnosed with IHD. Logistic regression analysis confirmed a significant association between Lp(a) concentrations and IHD (odds ratio (OR) 1.006; 95% CI 1.003-1.008; p<0.001). With an increase in Lp(a) by 1 mg/dl, the likelihood of having IHD increased by 1.006 times. With Lp(a) >50 mg/dL, the likelihood of IHD increased by 1.32 times (OR 1.320; 95% CI 1.254-1.390; p<0.001), with Lp(a) >180 mg/dL, by 2.06 times (OR 2.058; 95% CI 1.758-2.408), and with Lp(a) 30-50 mg/dL, by 1.1 times (OR 1.100; 95% CI 1.017-1.188; p=0.016).Conclusion      Every fourth person has an elevated Lp(a) concentration, which determines a high risk of developing cardiovascular diseases. Taking into account the accumulated data, early assessment of the Lp(a) concentration is necessary for all adults.

Causal Relevance of Lp(a) for Coronary Heart Disease and Stroke Types in East Asian and European Ancestry Populations: A Mendelian Randomization Study

BACKGROUND

Elevated plasma levels of Lp(a) [lipoprotein(a)] are a causal risk factor for coronary heart disease and stroke in European individuals, but the causal relevance of Lp(a) for different stroke types and in East Asian individuals with different Lp(a) genetic architecture is uncertain.

METHODS

We measured plasma levels of Lp(a) in a nested case-control study of 18 174 adults (mean [SD] age, 57 [10] years; 49% female) in the China Kadoorie Biobank (CKB) and performed a genome-wide association analysis to identify genetic variants affecting Lp(a) levels, with replication in ancestry-specific subsets in UK Biobank. We further performed 2-sample Mendelian randomization analyses, associating ancestry-specific Lp(a)-associated instrumental variants derived from CKB or from published data in European individuals with risk of myocardial infarction (n=17 091), ischemic stroke (IS [n=29 233]) and its subtypes, or intracerebral hemorrhage (n=5845) in East Asian and European individuals using available data from CKB and genome-wide association analysis consortia.

RESULTS

In CKB observational analyses, plasma levels of Lp(a) were log-linearly and positively associated with higher risks of myocardial infarction and IS, but not with ICH. In genome-wide association analysis, we identified 29 single nucleotide polymorphisms independently associated with Lp(a) that together explained 33% of variance in Lp(a) in Chinese individuals. In UK Biobank, the lead Chinese variants identified in CKB were replicated in 1260 Chinese individuals, but explained only 10% of variance in Lp(a) in European individuals. In Mendelian randomization analyses, however, there were highly concordant effects of Lp(a) across both ancestries for all cardiovascular disease outcomes examined. In combined analyses of both ancestries, the proportional reductions in risk per 100 nmol/L lower genetically predicted Lp(a) levels for myocardial infarction were 3-fold greater than for total IS (rate ratio, 0.78 [95% CI, 0.76-0.81] versus 0.94 [0.92-0.96]), but were similar to those for large-artery IS (0.80 [0.73-0.87]; n=8134). There were weaker associations with cardioembolic IS (0.92 [95% CI, 0.86-0.98]; n=11 730), and no association with small-vessel IS (0.99 [0.91-1.07]; n=12 343) or with intracerebral hemorrhage (1.08 [0.96-1.21]; n=5845).

CONCLUSIONS

The effects of Lp(a) on risk of myocardial infarction and large-artery IS were comparable in East Asian and European individuals, suggesting that people with either ancestry could expect comparable proportional benefits for equivalent reductions in Lp(a), but there was little effect on other stroke types.

Long-Term Changes to Cardiovascular Biomarkers After Hormone Therapy in the Women's Health Initiative Hormone Therapy Clinical Trials

OBJECTIVE

To assess the long-term changes in cardiovascular biomarkers during the WHI (Women's Health Initiative) hormone therapy (HT) clinical trials of conjugated equine estrogens (CEE) alone and CEE plus medroxyprogesterone acetate (MPA).

METHODS

HT trial participants from the CEE alone (n=1,188, 0.625 mg/d CEE or placebo) and the CEE+MPA (n=1,508, 0.625 mg/d CEE plus continuous 2.5 mg/d MPA or placebo) trials provided blood samples at baseline and after 1, 3, and 6 years. Low-density lipoprotein cholesterol (LDL-C; primary endpoint), high-density lipoprotein cholesterol (HDL-C), triglycerides, total cholesterol, lipoprotein(a), glucose, insulin, and homeostatic model assessment for insulin resistance were measured. Repeated-measures regression models estimated the geometric means of each log-transformed biomarker by restricted maximum likelihood. A constant treatment effect across visits was used to estimate the overall effect, expressed as a ratio of geometric means, and was complemented with geometric means (95% CIs) by randomization group and corresponding ratios of geometric means (95% CI; HT vs placebo) at each visit.

RESULTS

During the intervention phase of the CEE-alone trial, randomization to CEE reduced LDL-C by 11% over 6 years (ratio of geometric means 0.89, 95% CI, 0.88-0.91, P <.001). The overall reduction in LDL-C was similar for CEE+MPA relative to placebo (ratio of geometric means 0.88, 95% CI, 0.86-0.89, P <.001). Relative to placebo, HDL-C and triglycerides were 13.0% and 7.0% higher with CEE and CEE+MPA, respectively. The homeostatic model assessment for insulin resistance decreased by 14.0% and 8.0% for CEE-alone and CEE+MPA trial participants, respectively. Relative to placebo, lipoprotein(a) decreased by 15.0% and 20.0% for participants randomized to CEE alone and CEE+MPA, respectively.

CONCLUSION

Lipoprotein(a), LDL-C, and homeostatic model assessment for insulin resistance were lower and HDL-C levels were higher for HT compared with placebo. Triglycerides increased in both the CEE and CEE+MPA trials, however. Future research should assess whether other progestogens attenuate the effect of estrogen on HDL-C. These results may be used to counsel younger menopausal women with bothersome symptoms who are deciding whether to initiate oral HT within the context of published effects of oral HT on rates of cardiovascular events.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov , NCT00000611.

Association of Lp(a) With Stroke and Cerebral Injury on MRI: Insights From the HCHS/SOL (Hispanic Community Health Study/Study of Latinos) and Investigation of Neurocognitive Aging MRI (SOL-INCA MRI)

BACKGROUND

Lp(a) (lipoprotein[a]) is a risk factor for cardiovascular disease; however, its association with cerebrovascular disease is not as well established.

METHODS

Data from a population-based cohort of Hispanics/Latinos included 16 333 individuals with baseline Lp(a) levels (nmol/L) and self-reported prevalent stroke or transient ischemic attack (TIA). A subset of 2642 individuals with brain magnetic resonance imaging was also included. Linear and multivariate logistic regression assessed the association of Lp(a) with (1) self-reported stroke or TIA, (2) cerebral injury defined as self-reported stroke or TIA or evidence of a stroke on brain magnetic resonance imaging, (3) white matter hyperintensity volume, and (4) silent brain infarcts. Sampling weights were utilized given the HCHS/SOL (Hispanic Community Health Study/Study of Latinos) complex sample design.

RESULTS

Mean age±SE was 41.1±0.3 years, 52.0% female, and median interquartile range (Q1, Q3) Lp(a) level of 19.7 (7.3-60.6) nmol/L; brain magnetic resonance imaging subset mean age±SE was 49.9±0.4 years, 56.4% female, and median (interquartile range) Lp(a) level of 21.7 (8.1-62.9) nmol/L. Each unit increase in log-transformed Lp(a) was associated with higher odds of self-reported stroke or TIA (odds ratio, 1.13 [95% CI, 1.01-1.27]; P=0.03). Lp(a) levels in the highest quintile (>77 nmol/L) were significantly associated with higher odds of prevalent stroke or TIA compared with Lp(a) <6 nmol/L (first quintile: odds ratio, 1.74 [95% CI, 1.09-2.77]; P=0.02). The highest proportion of cerebral injury was noted in Q5, while the lowest proportion was noted in Q2. When comparing Lp(a) >77 nmol/L with Lp(a) of 6 to <13 nmol/L (second quintile), a significant association was found between Lp(a) and cerebral injury that persisted after fully adjusted models (odds ratio, 2.03 [95% CI, 1.05-3.93]; P=0.03). Each unit increase in log-Lp(a) was associated with a 0.10 increase in log-white matter hyperintensity (β, 0.10; P=0.005). No significant association was found between Lp(a) and silent brain infarcts.

CONCLUSIONS

Lp(a) is independently and significantly associated with prevalent stroke/TIA, and white matter hyperintensity, in a large diverse population of Hispanics/Latinos.

Serum Lipoprotein(a) Levels and Their Association with Atherosclerotic Cardiovascular Disease in Japan

AIMS

To investigate the distribution of lipoprotein(a) (Lp(a)) and its association with atherosclerotic cardiovascular disease (ASCVD) in Japanese patients at high risk for ASCVD using a health insurance database.

METHODS

Between July 2013 and June 2021, patients eligible for ASCVD prevention according to the 2017 Japan Atherosclerosis Society (JAS) guidelines with documented Lp(a) test results were extracted from the Medical Data Vision claims database and divided into three groups: primary prevention high-risk (Group I), secondary prevention (Group II) and secondary prevention high-risk (Group III). Data on lipid levels, cardiovascular morbidity risk factors and lipid-lowering treatments were extracted.

RESULTS

Of 700,580 patients with documented low-density lipoprotein cholesterol (LDL-C), 2,967 (0.42%) were tested for Lp(a). In 2,170 eligible patients, the median [interquartile range] serum concentration of Lp(a) was 13.9 [7.5-24.6] mg/dL, with 151 patients (7.0%) above the recommended risk threshold of ≥ 50 mg/dL. Lp(a) levels increased with risk across all prevention groups. Being in the highest Lp(a) quintile (Q5) was associated with an increased frequency of ASCVD (28.9% versus 18.9% in the lowest quintile (Q1) for unstable angina; 18.7% versus 10.1% for myocardial infarction; 27.9% versus 17.0% for ischemic stroke). In the secondary prevention groups, the proportion of patients meeting an LDL-C target of ＜70 mg/dL decreased from 30.2% in Q1 to 19.0% in Q5 for Group II and from 32.9% to 16.3% for Group III.

CONCLUSIONS

Despite a high prevalence of Lp(a) ≥ 50mg/dL in Japanese patients at high risk for ASCVD, it found that the Lp(a) testing rate was very low.

Long-read transcriptomics of a diverse human cohort reveals widespread ancestry bias in gene annotation

Accurate gene annotations are fundamental for interpreting genetic variation, cellular function, and disease mechanisms. However, current human gene annotations are largely derived from transcriptomic data of individuals with European ancestry, introducing potential biases that remain uncharacterized. Here, we generate over 800 million full-length reads with long-read RNA-seq in 43 lymphoblastoid cell line samples from eight genetically-diverse human populations and build a cross-ancestry gene annotation. We show that transcripts from non-European samples are underrepresented in reference gene annotations, leading to systematic biases in allele-specific transcript usage analyses. Furthermore, we show that personal genome assemblies enhance transcript discovery compared to the generic GRCh38 reference assembly, even though genomic regions unique to each individual are heavily depleted of genes. These findings underscore the urgent need for a more inclusive gene annotation framework that accurately represents global transcriptome diversity.

Rethinking cardiovascular risk: The emerging role of lipoprotein(a) screening

Lipoprotein(a) [Lp(a)] is a genetically inherited, independent risk factor for cardiovascular disease (CVD), affecting approximately 20-25% of the global population. Elevated Lp(a) levels are associated with a 2-3-fold increased risk of myocardial infarction and aortic valve stenosis, comparable to the risk seen in individuals with familial hypercholesterolemia. Despite its clinical relevance, the integration of Lp(a) screening into routine practice has been limited by inconsistent measurement techniques and a lack of targeted treatments. Recent advancements, including improved assays and the development of potential Lp(a)-lowering therapies, have renewed focus on the importance of Lp(a) screening. This review aims to clarify the role of Lp(a) in cardiovascular health by examining current evidence on who should be screened, when screening should occur, and the most accurate methods for measuring Lp(a). Key recommendations include universal, one-time screening for adults, selective screening for high-risk pediatric patients, and special considerations for individuals with conditions such as familial hypercholesterolemia and chronic kidney disease. Advances in assay technology now allow for more precise Lp(a) measurement, supporting better risk stratification. Additionally, emerging therapies that specifically target elevated Lp(a) levels could lead to more personalized management of CVD risk. Our findings support the integration of Lp(a) screening into routine cardiovascular risk assessment, highlighting its potential to improve early detection and prevention strategies across diverse patient populations.

The influence of lipoprotein(a) on aortic valve calcification in patients undergoing transcatheter aortic valve replacement

BACKGROUND

Elevated levels of lipoprotein(a) (Lp[a]) have been recognized as substantial risk factors for cardiovascular disease and aortic stenosis (AS). However, the specific role of Lp(a) in promoting aortic valve calcification (AVC) and influencing mortality in elderly, multimorbid patients undergoing transcatheter aortic valve replacement (TAVR) remains unclear and warrants further investigation.

METHODS

A retrospective analysis was conducted on all consecutive patients who underwent TAVR between August 2019 and June 2020 at our clinic. Patients with missing data or prior aortic valve replacement were excluded. The study cohort was stratified based on an Lp(a) threshold of 60 mg/dl according to guidelines for lipoprotein apheresis in UK and Germany.1,2 RESULTS: In total, 454 patients were included into the analysis. Mean age was 81 ± 6 years and patients presented with a notable cardiovascular risk profile. Lp(a) values ≥ 60 mg/dl were detected in 102 (22.5%) patients, while 352 (77.5%) had Lp(a) values < 60 mg/dl. The median calcium volume of the total cohort was 894.5 [570.8; 1,382.8] mm2. No significant difference was observed between the groups (p = 0.83). Furthermore, Lp(a) did not emerge as a statistically significant predictor of calcium levels before TAVR. Notably, male gender (B = 404.11, p < 0.001) and mean trans-valvular pressure gradient (B = 15.64, p < 0.001) were identified as the strongest coefficients within the robust regression analysis. Log-rank tests indicated no prognostic utility of Lp(a) for 30-day all-cause mortality (p = 0.30) or 40 months long-term all-cause mortality (p = 0.60).

CONCLUSION

Lp(a) might not exert a significant effect on calcification levels or all-cause mortality in patients undergoing TAVR. Despite the study's highly selected population, these results align with current research, supporting the assumption that the influence of Lp(a) may be confined to the early stages of AS and its progression.

Cardiovascular disease lipids and lipoproteins biomarker standardization

Cardiovascular disease (CVD) is the leading cause of mortality in the United States and globally. This review describes changes in CVD lipid and lipoprotein biomarker measurements that occurred in line with the evolution of clinical practice guidelines for CVD risk assessment and treatment. It also discusses the level of comparability of these biomarker measurements in clinical practice. Comparable and reliable measurements are achieved through assay standardization, which not only depends on correct test calibration but also on factors such as analytical sensitivity, selectivity, susceptibility to factors that can affect the analytical measurement process, and the stability of the test system over time. The current status of standardization for traditional and newer CVD biomarkers is discussed, as are approaches to setting and achieving standardization goals for low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), triglycerides (TG), lipoprotein(a) (Lp(a)), apolipoproteins (apo) A-I and B, and non-HDL-C. Appropriate levels of standardization for blood lipids are maintained by the Centers for Disease Control and Prevention's (CDC) CVD Biomarkers Standardization Program (CDC CVD BSP) using the analytical performance goals recommended by the National Cholesterol Education Program. The level of measurement agreement that can be achieved is dependent on the characteristics of the analytes and differences in measurement principles between reference measurement procedures and clinical assays. The technical and analytical limitations observed with traditional blood lipids are not observed with apolipoproteins. Additionally, apoB and Lp(a) may more accurately capture CVD risk and residual CVD risk, respectively, than traditional lipids, thus prompting current guidelines to recommend apolipoprotein measurements. This review further discusses CDC's approach to standardization and describes the analytical performance of traditional blood lipids and apoA-I and B observed over the past 11 years. The reference systems for apoA-I and B, previously maintained by a single laboratory, no longer exist, thus requiring the creation of new systems, which is currently underway. This situation emphasizes the importance of a collaborative network of laboratories, such as CDC's Cholesterol Reference Methods Laboratory Network (CRMLN), to ensure standardization sustainability. CDC is supporting the International Federation of Clinical Chemistry and Laboratory Medicine's (IFCC) work to establish such a network for lipoproteins. Ensuring comparability and reliability of CVD biomarker measurements through standardization remains critical for the effective implementation of clinical practice guidelines and for improving patient care. Utilizing experience gained over three decades, CDC CVD BSP will continue to improve the standardization of traditional and emerging CVD biomarkers together with stakeholders.

Coronary Artery Calcium Scoring in the Context of Widespread Lipoprotein(a) Testing: Clinical Considerations and Implications for Lipid-Lowering Therapies

PURPOSE OF REVIEW

This review evaluates the interplay between lipoprotein(a) [Lp(a)] and coronary artery calcium (CAC) for risk prediction and preventive therapy selection, with a special emphasis on scenarios where these measures are discordant, particularly in otherwise intermediate-risk, primary prevention patients.

RECENT FINDINGS

Observational studies and meta-analyses indicate a nuanced relationship between elevated Lp(a) levels and CAC burden and progression. Elevated Lp(a) is associated with an increased risk of CAC presence and progression; although, there is notable variability across studies. CAC predicts a similarly elevated risk in patients with low and high Lp(a). Joint elevation of Lp(a) and CAC is associated with a very high-risk patient subset. Elevated Lp(a) should prompt consideration of CAC testing for further risk stratification. In the future, we anticipate that an elevated CAC score could prompt consideration of testing for Lp(a) in select patients, as identifying or confirming elevated Lp(a) may help guide the use of dedicated Lp(a)-lowering therapies in very high-risk primary prevention populations.

Lipoprotein(a) as a Pharmacological Target: Premises, Promises, and Prospects

Atherosclerotic cardiovascular disease is a major health concern worldwide and requires effective preventive measures. Lp(a) (lipoprotein [a]) has recently garnered attention as an independent risk factor for astherosclerotic cardiovascular disease, with proinflammatory and prothrombotic mechanisms contributing to its atherogenicity. On an equimolar basis, Lp(a) is ~5 to 6 times more atherogenic than particles that have been widely associated with adverse cardiovascular outcomes, such as LDL (low-density lipoprotein). Lp(a) can enter the vessel wall, leading to the accumulation of oxidized phospholipids in the arterial intima, which are crucial for initiating plaque inflammation and triggering vascular disease progression. In addition, Lp(a) may cause atherothrombosis through interactions between apoA (apolipoprotein A) and the platelet PAR-1 (protease-activated receptor 1) receptor, as well as competitive inhibition of plasminogen. Because Lp(a) is mostly determined on genetic bases, a 1-time assessment in a lifetime can suffice to identify patients with elevated levels. Mendelian randomization studies and post hoc analyses of randomized trials of LDL cholesterol-lowering drugs showed a causal link between Lp(a) concentrations and cardiovascular outcomes, with therapeutic reduction of Lp(a) expected to contribute to estimated cardiovascular risk mitigation. Many Lp(a)-lowering drugs, including monoclonal antibodies, small interfering ribonucleic acids, antisense oligonucleotides, small molecules, and gene editing compounds, are at different stages of clinical investigation and show promise for clinical use. In particular, increased Lp(a) testing and treatment are expected to have a substantial impact at the population level, enabling the identification of high-risk individuals and the subsequent prevention of a large number of cardiovascular events. Ongoing phase 3 trials will further elucidate the cardiovascular benefits of Lp(a) reduction over the long term, offering potential avenues for targeted interventions and improved cardiovascular outcomes.

Can Lp(a) become the next A1C? A case for digital health management tools to overcome inertia to Lipoprotein (a) testing

Despite its known correlations with risk of cardiovascular disease, awareness and testing for Lipoprotein (a) lags that of other serological markers with estimates that less than 1% of the US population have undergone screening. Herein we outline how digital tools framed around motivational models (COM-B and SEM), might help increase likelihood of patients seeking Lp(a) testing as part of their managed care. Furthermore, we highlight how recent trends in prescription of GLP-1 receptor antagonists are serving to motivate patients to manage biomarkers related to T2D and obesity, which are also relevant in cardiovascular disease. Capitalizing on this trend to stimulate interest in Lp(a) management could have near term consequence, and with disease modifying therapies in development ultimately improve outcomes in cardiovascular disease.

Temporal trends in lipoprotein(a) testing among United States veterans from 2014 to 2023

Objective

Lipoprotein (a) [Lp(a)] is a causal, genetically-inherited risk amplifier for atherosclerotic cardiovascular disease (ASCVD). Practice guidelines increasingly recommend broad Lp(a) screening among various populations to optimize preventive care. Corresponding changes in testing rates and population-level detection of elevated Lp(a) in recent years has not been well described.

Methods

Using Veterans Affairs electronic health record data, we performed a retrospective cohort study evaluating temporal trends in Lp(a) testing and detection of elevated Lp(a) levels (defined as greater than 50 mg/dL) from January 1, 2014 to December 31, 2023 among United States Veterans without prior Lp(a) testing. Testing rates were stratified based on demographic and clinical factors to investigate possible drivers for and disparities in testing: age, sex, race and ethnicity, history of ASCVD, and neighborhood social vulnerability.

Results

Lp(a) testing increased nationally from 1 test per 10,000 eligible Veterans (558 tests) in 2014 to 9 tests per 10,000 (4,440 tests) in 2023, while the proportion of elevated Lp(a) levels remained stable. Factors associated with higher likelihood of Lp(a) testing over time were a history of ASCVD, Asian race, and residing in neighborhoods with less social vulnerability.

Conclusion

Despite a 9-fold increase in Lp(a) testing among US Veterans over the last decade, the overall testing rate remains extremely low. The steady proportion of Veterans with elevated Lp(a) over time supports the clinical utility of testing expansion. Efforts to increase testing, especially among Veterans living in neighborhoods with high social vulnerability, will be important to reduce emerging disparities as novel therapeutics to target Lp(a) become available.

Role of Lipoprotein (A) in aortic valve stenosis: Novel disease mechanisms and emerging pharmacotherapeutic approaches

Lipoprotein(a) (Lp(a)) has garnered increasing attention as a significant contributor to the pathogenesis of aortic stenosis (AS), prompting a focused investigation into innovative pharmacological strategies to target this lipoprotein and its associated risks. Despite its recognized role in AS progression, Lp(a) often remains overlooked in clinical assessments, mirroring the broader challenges observed in holistic disease management. This review delves into the mechanistic intricacies of Lp(a) involvement in AS pathophysiology and its potential as a therapeutic target. Drawing parallels with the imperative for healthcare providers to proactively engage with patients regarding treatment regimens, this review underscores the essential role of cardiologists and physicians in recognizing and addressing Lp(a) as a modifiable risk factor in AS management. Furthermore, it explores promising avenues of novel drug approaches, including emerging pharmacotherapies and targeted interventions, aimed at modulating Lp(a) levels and attenuating AS progression. By navigating the complexities of Lp(a) modulation and its implications for AS management, this review aims to bridge critical gaps in understanding and clinical practice, ultimately optimizing treatment strategies and improving patient outcomes in the realm of AS therapeutics.

Lipoprotein(a) and the atherosclerotic burden - Should we wait for clinical trial evidence before taking action?

The fact that lipoprotein(a) levels should be regarded as a causal residual risk factor in the atherosclerotic cardiovascular diseases (ASCVD) is now a no-brainer. This review article aims to summarize the latest evidence supporting the causal role of lipoprotein(a) in ASCVD and the potential strategies to reduce the lipoprotein(a) burden until clinical trial results are available. Epidemiological and genetic data demonstrate the causal link between lipoprotein(a) and increased ASCVD risk. That being said, a specific question comes to mind: "must we wait for outcome trials in order to take action?". Given that lipoprotein(a) levels predict incident ASCVD in both primary and secondary prevention contexts, with a linear risk gradient across its distribution, measuring lipoprotein(a) can unequivocally help identify patients who may later benefit from specific lipoprotein(a)-lowering therapies. This understanding has led various National Societies to recommend dosing lipoprotein(a) in high-risk individuals and to support the recommendation of measuring lipoprotein(a) levels at least once in every adult for risk stratification.

Lipoprotein(a) and cardiovascular disease

One in five people are at high risk for atherosclerotic cardiovascular disease and aortic valve stenosis due to high lipoprotein(a). Lipoprotein(a) concentrations are lowest in people from east Asia, Europe, and southeast Asia, intermediate in people from south Asia, the Middle East, and Latin America, and highest in people from Africa. Concentrations are more than 90% genetically determined and 17% higher in post-menopausal women than in men. Individuals at a higher cardiovascular risk should have lipoprotein(a) concentrations measured once in their lifetime to inform those with high concentrations to adhere to a healthy lifestyle and receive medication to lower other cardiovascular risk factors. With no approved drugs to lower lipoprotein(a) concentrations, it is promising that at least five drugs in development lower concentrations by 65-98%, with three currently being tested in large cardiovascular endpoint trials. This Review covers historical perspectives, physiology and pathophysiology, genetic evidence of causality, epidemiology, role in familial hypercholesterolaemia and diabetes, management, screening, diagnosis, measurement, prevention, and future lipoprotein(a)-lowering drugs.

The prevalence, patients' characteristics, and hyper-Lp(a)-emia risk factors in the Polish population. The first results from the PMMHRI-Lp(a) Registry

BACKGROUND

The knowledge on the prevalence of elevated lipoprotein(a) (Lp(a)), patients' characteristics, and nongenetic risk factors is scarce in some regions including Poland, the largest Central and Eastern European country. Thus, we aimed to present the results from the Lp(a) registry established in Poland's 2nd largest, supra-regional hospital - the Polish Mother's Memorial Hospital Research Institute (PMMHRI).

METHODS

The PMMHRI-Lp(a)-Registry was established in January 2022. Since that time all consecutive patients of the Departments of Cardiology, Endocrinology, and outpatient cardiology, diabetology and metabolic clinics have been included. The indications for Lp(a) measurement in the registry are based on the 2021 Polish Lipid Guidelines and new Polish recommendations on the management of elevated Lp(a) (2024). Lp(a) was determined using Sentinel's Lp(a) Ultra, an Immunoturbidimetric quantitative test (Sentinel, Milan, Italy), and the results are presented in mg/dL.

RESULTS

511 patients were included in the registry between Jan 2022 and 15th May 2024. The mean age of patients was 48.21 years. Female patients represented 53.42 % of the population. Elevated Lp(a) levels above 30 and 50 mg/dL were detected in 142 (27.79 %), and 101 (19.8 %) patients, respectively. The mean Lp(a) level was 30.45 ± 42.50 mg/dL, with no significant sex differences [mean for men: 28.80 mg/dL; women: 31.89 mg/dL]. There were also no significant differences between those with and without: coronary artery disease (CAD), dyslipidemia, stroke, heart failure, cancer, diabetes, chronic kidney disease, and thyroid disease. The significant Lp(a) level difference was observed in those with a history of myocardial infarction (MI) vs those without (51.47 ± 55.16 vs 28.09 ± 37.51 mg/dL, p < 0.001). However, when we divided those with premature vs no premature MI, no significant difference in Lp(a) level was observed (51.43 ± 57.82 vs 51.52 ± 53.18 mg/dL, p = 0.95). Lipid-lowering therapy (LLT) at baseline did not significantly affect Lp(a) level, with only significant differences for the highest doses of rosuvastatin (p < 0.05) and in those treated with ezetimibe (as a part of the combination therapy; 44.73 ± 54.94 vs 26.84 ± 37.11 mg/dL, p < 0.001). For selected patients (n = 43; 8.42 %) with at least two Lp(a) measurements (mean time distance: 7 ± 5 months, range 1-20 months) we did not observe statistically significant visit-to-visit variability (mean difference: 3.25 mg/dL; r = 0.079, p = 0.616). While dividing the whole population into those with Lp(a) ≤30 mg/dL and > 30 mg/dL, the only hyper-Lp(a)-emia prevalence differences were seen for FH diagnosis (12.88 vs 21.43; p = 0.017), MI prevalence (6.52 vs 16.90 %; p < 0.001), thyroid disease diagnosis (18.14 vs 26.76 %; p = 0.033) and ezetimibe treatment (18.58 vs 30.77 %, p = 0.036). A similar pattern was observed while dividing the whole population on those with Lp(a) ≤50 mg/dL (125 nmol/L) and > 50 mg/dL (125 nmol/L) except for no statistical difference for thyroid disease.

CONCLUSIONS

These results strongly emphasize that Lp(a) should be measured commonly, as its high level is highly prevalent (even every 3rd patient) in patients at cardiovascular disease (CVD) risk in primary and secondary prevention, requiring risk re-stratification and optimization of the treatment. This is especially important in the regions that characterize baseline high CVD risk, which refers to most CEE countries, including Poland.

Testing practices and clinical management of lipoprotein(a) levels: A 5-year retrospective analysis from the Johns Hopkins Hospital

Objective

Elevated lipoprotein(a) [Lp(a)] is an independent, genetically determined risk factor for atherosclerotic cardiovascular disease (ASCVD). We evaluated the frequency of testing for elevated Lp(a) and subsequent management at the Johns Hopkins Hospital, a large academic medical center, over a 5-year period.

Methods

The Johns Hopkins Hospital (JHH) electronic medical record was queried to identify patients with an encounter between 2017 and 2021, either with established ASCVD or at increased risk, defined as being on any lipid lowering medication or having LDL-C ≥ 190 mg/dL. The frequency of Lp(a) testing and of elevated levels were identified for each year.

Results

Among 111,350 unique adult patients, 2,785 (2.5 %) had at least one Lp(a) test. Patients with Lp(a) testing, compared to those without testing, were younger (mean age 56 years vs. 66 years), more often female (49 % vs. 44 %), Black (24.7 % vs. 24.6 %) or "other" race/ethnicity (12 % vs 10 %), and had higher LDL-C levels (median 118 vs. 91 mg/dL; p < 0.001). The number and frequency of Lp(a) testing increased from 167 (0.57 %) in 2017 to 1155 (5.67 %) in 2021. Lp(a) levels were abnormal in 43.4 % of patients (moderate [75-125 nmol/L]: 10.3 %, high [126-600 nmol/L]: 32.2 %, severe [>600 nmol/L]: 0.9 %). Among 920 patients with high or severe Lp(a) levels, 200 (22 %) had a subsequent referral to cardiology or lipid specialist, and 180 (20 %) had a new lipid-lowering medication prescribed in the subsequent 18 months.

Conclusion

Based on a single-center experience, the frequency of incident Lp(a) testing among increased-risk patients was low but increased significantly over 5-years, likely due to Lipid Clinic referrals with reflex Lp(a) testing and greater awareness about this risk factor. Future work should target appropriate population based Lp(a) testing strategies and clinical decision-making regarding risk management once Lp(a) elevation is diagnosed.

Lipoprotein(a) in interventional cardiology: identifying patients at highest risk of recurrent cardiovascular events through early recognition - a case based review

INTRODUCTION

Lipoprotein(a) [Lp(a)] is linked to higher risks of atherosclerotic cardiovascular disease (ASCVD). Current guideline recommendations are quite liberal on measuring Lp(a) (Class IIa, Level C), and may lead to underuse among (interventional) cardiologists.

AREAS COVERED

This case-based narrative review outlines four clinical cases of patients with elevated Lp(a) to illustrate its pathophysiological impact on coronary artery disease (CAD). The expert consensus statements from the American Heart Association (AHA) and European Atherosclerosis Society (EAS) served as the basis of this review. More recent publications, from 2023 to 2024, were accessed through the MEDLINE online library.

EXPERT OPINION

We highlighted the importance of routine Lp(a) measurement in identifying patients at high risk for atherosclerosis, necessitating potent risk mitigation. Measuring Lp(a) helps clinicians identify which patients are at highest residual risk, who require potent pharmacological treatment and special attention during catheter interventions. As noninvasive and advanced intravascular imaging modalities evolve, future catheterization laboratories will integrate advanced imaging, diagnostics, and treatment, facilitating tailored patient care. Knowing Lp(a) levels is crucial in this context. While Lp(a)-lowering drugs are currently investigated in clinical trials, it is of paramount importance to know Lp(a) levels and strive toward aggressive management of other modifiable risk factors in patients with elevated Lp(a) and established symptomatic CAD being diagnosed or treated in catheterization laboratories.

Exploring the Effect of Thyroid Hormone on Serum Lipoprotein (a) Levels in Patients With Thyroid Hormone Dysfunction: A Systematic Review

Genetic variations among people mainly determine the blood levels of lipoprotein (a) (Lp(a)), and it is relatively stable throughout one's lifetime. Nevertheless, there could still be other factors that control the Lp(a) level. Thyroid hormones are known to influence the serum lipid level by regulating the expression of key enzymes that are involved in lipid metabolism. Both hypo and hyperthyroidism are associated with changes in lipid levels. Even though thyroid hormone abnormalities have been shown to alter traditional lipid parameters like low-density lipoprotein (LDL-C), its influence on Lp(a) has not been established. This review aims to identify the relationship between Lp(a) and thyroid hormones by reviewing data from correlative studies and observing treatment-related Lp(a) level changes in thyroid disorders from interventional studies. We searched MEDLINE, Cochrane, and Google Scholar databases with predefined search criteria and search strategies for paper identification. Individual reviewers reviewed identified papers for selection. Finalized papers were reviewed for Lp(a) levels and their responses to treatment in patients with thyroid disorders to establish the relationship between Lp(a) and thyroid hormone. We concluded that the data were limited and sometimes contradicted one another to establish a clear relationship between Lp(a) and thyroid hormones. Even though correlative studies data showed strong indications that overt-hypothyroidism was associated with high Lp(a) levels, thyroid hormone replacement studies did not show any significant changes in Lp(a) levels compared to pre-treatment in patients with both overt-hypothyroidism and subclinical hypothyroidism. More clinical trials focusing on Lp(a) with longer periods of treatment and follow-up in thyroid patients are needed to establish the relationship between the two. The possibility of dose-related Lp(a) responses to thyroid hormone treatment should also be explored.

Elevated lipoprotein(a) levels: A crucial determinant of cardiovascular disease risk and target for emerging therapies

Cardiovascular disease (CVD) remains a significant global health challenge despite advancements in prevention and treatment. Elevated Lipoprotein(a) [Lp(a)] levels have emerged as a crucial risk factor for CVD and aortic stenosis, affecting approximately 20 of the global population. Research over the last decade has established Lp(a) as an independent genetic contributor to CVD and aortic stenosis, beginning with Kare Berg's discovery in 1963. This has led to extensive exploration of its molecular structure and pathogenic roles. Despite the unknown physiological function of Lp(a), studies have shed light on its metabolism, genetics, and involvement in atherosclerosis, inflammation, and thrombosis. Epidemiological evidence highlights the link between high Lp(a) levels and increased cardiovascular morbidity and mortality. Newly emerging therapies, including pelacarsen, zerlasiran, olpasiran, muvalaplin, and lepodisiran, show promise in significantly lowering Lp(a) levels, potentially transforming the management of cardiovascular disease. However, further research is essential to assess these novel therapies' long-term efficacy and safety, heralding a new era in cardiovascular disease prevention and treatment and providing hope for at-risk patients.

Frequency of lipoprotein(a) testing and its levels in Pakistani population

BACKGROUND

Lipoprotein(a) [Lp(a)] is a highly atherogenic particle identified as an independent risk factor for the development of atherosclerotic cardiovascular disease (ASCVD). This study aimed to investigate the frequency of Lp(a) testing and the incidence of elevated Lp(a) levels in the Pakistani population.

METHODS

For this observational study, Lp(a) and lipid profile data from five years (June 2015 to October 2020) were acquired from the electronic patient records of a diagnostic laboratory with a countrywide network. The association of age and total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), non-HDL, and triglyceride (TG) levels with two thresholds for Lp(a), that is, <30 mg/dL and ≥30 mg/dL, was calculated using the Kruskal-Wallis test, while the association between Lp(a) levels and lipid variables was calculated using Spearman correlation.

RESULTS

For five years, 1060 tests were conducted, averaging 212 tests per year. Of these, 37.2% showed Lp(a) levels above 30 mg/dL. No significant differences were observed in the results between males and females. However, younger individuals displayed significantly higher Lp(a) levels. Additionally, there was only a weak correlation between the Lp(a) levels and other lipid variables.

CONCLUSION

Despite being recognized as a risk factor for ASCVD in the Pakistani population, only a small proportion of the large population underwent Lp(a) testing. Moreover, a significant proportion of the population exceeded this threshold.

The implications of measuring lipoprotein(a) in clinical practice

Lipoprotein(a) (Lp(a)) is a well-recognized causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valve stenosis. There are ongoing challenges with screening and management in primary and secondary prevention; however, future recommendations for clinical practice await the outcomes of clinical trials that are in progress.

Exploring the Interplay between Diabetes and Lp(a): Implications for Cardiovascular Risk

PURPOSE OF REVIEW

The objective of this manuscript is to review and describe the relationship between Lp(a) and diabetes, exploring both their association and synergy as cardiovascular risk factors, while also describing the current evidence regarding the potential connection between low levels of Lp(a) and the presence of diabetes.

RECENT FINDINGS

Epidemiological studies suggest a potential relationship between low to very low levels of Lp(a) and diabetes. Lipoprotein(a), or Lp(a), is an intriguing lipoprotein of genetic origin, yet its biological function remains unknown. Elevated levels of Lp(a) are associated with an increased risk of cardiovascular atherosclerosis, and coexisting diabetes status confers an even higher risk. On the other hand, epidemiological and genetic studies have paradoxically suggested a potential relationship between low to very low levels of Lp(a) and diabetes. While new pharmacological strategies are being developed to reduce Lp(a) levels, the dual aspects of this lipoprotein's behavior need to be elucidated in the near future.

Genetics and Pathophysiological Mechanisms of Lipoprotein(a)-Associated Cardiovascular Risk

Elevated lipoprotein(a) is a genetically transmitted codominant trait that is an independent risk driver for cardiovascular disease. Lipoprotein(a) concentration is heavily influenced by genetic factors, including LPA kringle IV-2 domain size, single-nucleotide polymorphisms, and interleukin-1 genotypes. Apolipoprotein(a) is encoded by the LPA gene and contains 10 subtypes with a variable number of copies of kringle -2, resulting in >40 different apolipoprotein(a) isoform sizes. Genetic loci beyond LPA, such as APOE and APOH, have been shown to impact lipoprotein(a) levels. Lipoprotein(a) concentrations are generally 5% to 10% higher in women than men, and there is up to a 3-fold difference in median lipoprotein(a) concentrations between racial and ethnic populations. Nongenetic factors, including menopause, diet, and renal function, may also impact lipoprotein(a) concentration. Lipoprotein(a) levels are also influenced by inflammation since the LPA promoter contains an interleukin-6 response element; interleukin-6 released during the inflammatory response results in transient increases in plasma lipoprotein(a) levels. Screening can identify elevated lipoprotein(a) levels and facilitate intensive risk factor management. Several investigational, RNA-targeted agents have shown promising lipoprotein(a)-lowering effects in clinical studies, and large-scale lipoprotein(a) testing will be fundamental to identifying eligible patients should these agents become available. Lipoprotein(a) testing requires routine, nonfasting blood draws, making it convenient for patients. Herein, we discuss the genetic determinants of lipoprotein(a) levels, explore the pathophysiological mechanisms underlying the association between lipoprotein(a) and cardiovascular disease, and provide practical guidance for lipoprotein(a) testing.

Association between hepatic steatosis and lipoprotein(a) levels in non-alcoholic patients: A systematic review

BACKGROUND AND OBJECTIVES

It is well known that lipid abnormalities exist in the context of non-alcoholic fatty liver disease (NAFLD). The association between lipoprotein(a) [Lp(a)] levels and NAFLD is poorly understood. The main objective of the present study was to assess the association between Lp(a) levels and NAFLD.

METHODS

This systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (PROSPERO CRD42023392526). A literature search was performed to detect studies that evaluated the association between Lp(a) levels, NAFLD and steatohepatitis (NASH).

RESULTS

Ten observational studies, including 40,045 patients, were identified and considered eligible for this systematic review. There were 9266 subjects in the NAFLD groups and 30,779 individuals in the respective control groups. Five studies evaluated patients with NAFLD (hepatic steatosis was associated with lower Lp(a) levels in four studies, while the remaining showed opposite results). Two studies evaluating NASH patients showed that Lp(a) levels were not different compared to controls. However, the increment of Lp(a) levels was correlated with liver fibrosis in one of them. In addition, one study analyzed simultaneously patients with NAFLD and NASH, showing a neutral result in NAFLD patients and a positive relationship in NASH patients. Two studies that included patients with the new definition of metabolic-associated fatty liver disease (MAFLD) also showed neutral results.

CONCLUSION

Although there could be an association between Lp(a) levels and hepatic steatosis, the results of the studies published to date are contradictory and not definitive.

Lipoprotein(a) Levels in Disaggregated Racial and Ethnic Subgroups Across Atherosclerotic Cardiovascular Disease Risk Levels

Background

Lipoprotein(a) [Lp(a)] is a causal risk factor for atherosclerotic cardiovascular disease (ASCVD).

Objectives

The authors assessed differences in Lp(a) testing and levels by disaggregated race, ethnicity, and ASCVD risk.

Methods

This was a retrospective cohort study of patients from a large California health care system from 2010 to 2021. Eligible individuals were ≥18 years old, with ≥2 primary care visits, and complete race and ethnicity data who underwent Lp(a) testing. Race and ethnicity were self-reported and categorized as follows: non-Hispanic (NH) White, NH-Black, Hispanic (Mexican, Puerto Rican, other), NH-Asian (Asian Indian, Chinese, Filipino, Japanese, Korean, Vietnamese, other). Logistic regression models tested associations between elevated Lp(a) (≥50 mg/dL) and race, ethnicity, and ASCVD risk.

Results

13,689 (0.9%) individuals underwent Lp(a) testing with a mean age of 54.6 ± 13.8 years, 49% female, 28.8% NH Asian. Over one-third of those tested had Lp(a) levels ≥50 mg/dL, ranging from 30.7% of Mexican patients to 62.6% of NH-Black patients. The ASCVD risk of those tested varied by race: 73.6% of Asian Indian individuals had <5% 10-year risk, whereas 27.2% of NH-Black had established ASCVD. Lp(a) prevalence ≥50 mg/dL increased across the ASCVD risk spectrum. After adjustment, Hispanic (OR: 0.76 [95% CI: 0.66-0.88]) and Asian (OR: 0.88 [95% CI: 0.81-0.96]) had lower odds of Lp(a) ≥50 mg/dL, whereas Black individuals had higher odds (OR: 2.46 [95% CI: 1.97-3.07]).

Conclusions

Lp(a) testing is performed infrequently. Of those tested, Lp(a) levels were frequently elevated and differed significantly across disaggregated race and ethnicity groups. The prevalence of elevated Lp(a) increased with increasing ASCVD risk, with significant variation by race and ethnicity.

High lipoprotein(a): Actionable strategies for risk assessment and mitigation

High levels of lipoprotein(a) [Lp(a)] are causal for atherosclerotic cardiovascular disease (ASCVD). Lp(a) is the most prevalent inherited dyslipidemia and strongest genetic ASCVD risk factor. This risk persists in the presence of at target, guideline-recommended, LDL-C levels and adherence to lifestyle modifications. Epidemiological and genetic evidence supporting its causal role in ASCVD and calcific aortic stenosis continues to accumulate, although various facets regarding Lp(a) biology (genetics, pathophysiology, and expression across race/ethnic groups) are not yet fully understood. The evolving nature of clinical guidelines and consensus statements recommending universal measurements of Lp(a) and the scientific data supporting its role in multiple disease states reinforce the clinical merit to start population screening for Lp(a) now. There is a current gap in the implementation of recommendations for primary and secondary cardiovascular disease (CVD) prevention in those with high Lp(a), in part due to a lack of protocols for management strategies. Importantly, targeted apolipoprotein(a) [apo(a)]-lowering therapies that reduce Lp(a) levels in patients with high Lp(a) are in phase 3 clinical development. This review focuses on the identification and clinical management of patients with high Lp(a). Specifically, we highlight the clinical value of measuring Lp(a) and its use in determining Lp(a)-associated CVD risk by providing actionable guidance, based on scientific knowledge, that can be utilized now to mitigate risk caused by high Lp(a).

Impact of elevated lipoprotein(a) on coronary artery disease phenotype and severity

AIMS

A thorough characterization of the relationship between elevated lipoprotein(a) [Lp(a)] and coronary artery disease (CAD) is lacking. This study aimed to quantitatively assess the association of increasing Lp(a) levels and CAD severity in a real-world population.

METHODS AND RESULTS

This non-interventional, cross-sectional, LipidCardio study included patients aged ≥21 years undergoing angiography (October 2016-March 2018) at a tertiary cardiology centre, who have at least one Lp(a) measurement. The association between Lp(a) and CAD severity was determined by synergy between PCI with taxus and cardiac surgery (SYNTAX)-I and Gensini scores and angiographic characteristics. Overall, 975 patients (mean age: 69.5 years) were included; 70.1% were male, 97.5% had Caucasian ancestry, and 33.2% had a family history of premature atherosclerotic cardiovascular disease. Median baseline Lp(a) level was 19.3 nmol/L. Patients were stratified by baseline Lp(a): 72.9% had < 65 nmol/L, 21.0% had ≥100 nmol/L, 17.2% had ≥125 nmol/L, and 12.9% had ≥150 nmol/L. Compared with the normal (Lp(a) < 65 nmol/L) group, elevated Lp(a) groups (e.g. ≥ 150 nmol/L) had a higher proportion of patients with prior CAD (48.4% vs. 62.7%; P < 0.01), prior coronary revascularization (39.1% vs. 51.6%; P = 0.01), prior coronary artery bypass graft (6.0% vs. 15.1%; P < 0.01), vessel(s) with lesions (68.5% vs. 81.3%; P = 0.03), diffusely narrowed vessels (10.9% vs. 16.5%; P = 0.01) or chronic total occlusion lesions (14.3% vs. 25.2%; P < 0.01), and higher median SYNTAX-I (3.0 vs. 5.5; P = 0.01) and Gensini (10.0 vs. 16.0; P < 0.01) scores.

CONCLUSION

Elevated Lp(a) was associated with a more severe presentation of CAD. Awareness of Lp(a) levels in patients with CAD may have implications in their clinical management.

Lipoprotein(a), platelet function and cardiovascular disease

Lipoprotein(a) (Lp(a)) is associated with atherothrombosis through several mechanisms, including putative antifibrinolytic properties. However, genetic association studies have not demonstrated an association between high plasma levels of Lp(a) and the risk of venous thromboembolism, and studies in patients with highly elevated Lp(a) levels have shown that Lp(a) lowering does not modify the clotting properties of plasma ex vivo. Lp(a) can interact with several platelet receptors, providing biological plausibility for a pro-aggregatory effect. Observational clinical studies suggest that elevated plasma Lp(a) concentrations are associated with worse long-term outcomes in patients undergoing revascularization. Furthermore, in these patients, those with elevated plasma Lp(a) levels derive more benefit from prolonged dual antiplatelet therapy than those with normal Lp(a) levels. The ASPREE trial in healthy older individuals treated with aspirin showed a reduction in ischaemic events in those who had a single-nucleotide polymorphism in LPA that is associated with elevated Lp(a) levels in plasma, without an increase in bleeding events. In this Review, we re-examine the role of Lp(a) in the regulation of platelet function and suggest areas of research to define further the clinical relevance to cardiovascular disease of the observed associations between Lp(a) and platelet function.

Lipoprotein(a) and Long-Term Cardiovascular Risk in a Multi-Ethnic Pooled Prospective Cohort

BACKGROUND

Lipoprotein(a) (Lp[a]) is a causal genetic risk factor for atherosclerotic cardiovascular disease (ASCVD). There are limited long-term follow-up data from large U.S. population cohorts.

OBJECTIVES

This study examined the relationship of Lp(a) with ASCVD outcomes in a large, pooled, multi-ethnic U.S.

COHORT

METHODS

The study included data on Lp(a) and ASCVD outcomes from 5 U.S.

PROSPECTIVE STUDIES

MESA (Multi-Ethnic Study of Atherosclerosis), CARDIA (Coronary Artery Risk Development in Young Adults), JHS (Jackson Heart Study), FHS-OS (Framingham Heart Study-Offspring), and ARIC (Atherosclerosis Risk In Communities). Lp(a) levels were classified on the basis of cohort-specific percentiles. Multivariable Cox regression related Lp(a) with composite incident ASCVD events by risk group and diabetes status.

RESULTS

The study included 27,756 persons without previous ASCVD who were aged 20 to 79 years, including 55.0% women, 35.6% Black participants, and 7.6% patients with diabetes, with mean follow-up of 21.1 years. Compared with Lp(a) levels <50th percentile, Lp(a) levels in the 50th to <75th, 75th to <90th, and ≥90th percentiles had adjusted HRs of 1.06 (95% CI: 0.99-1.14), 1.18 (95% CI: 1.09-1.28), and 1.46 (95% CI: 1.33-1.59), respectively for ASCVD events. Elevated Lp(a) predicted incident ASCVD events similarly by risk group, sex, and race or ethnic groups, but more strongly in patients with vs without diabetes (interaction P = 0.0056), with HRs for Lp(a) levels ≥90th percentile of 1.92 (95% CI: 1.50-2.45) and 1.41 (95% CI: 1.28-1.55), respectively. Lp(a) also individually predicted myocardial infarction, revascularization, stroke, and coronary heart disease death, but not total mortality.

CONCLUSIONS

The study shows, in a large U.S. pooled cohort, that higher Lp(a) levels are associated with an increased ASCVD risk, including in patients with diabetes.

Elevated Lp(a): Guidance for Identifying and Managing Patients

Lipoprotein(a) (Lp(a)) is a unique low-density lipoprotein-like lipoprotein that is considered an independent and causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valve stenosis. The Lp(a) molecule also contains apolipoprotein A and apolipoprotein B, which collectively promote atherosclerosis, thrombosis, and inflammation. Lp(a) is highly genetic and minimally responsive to nonpharmacological measures. Lp(a) serum levels ≥125 nmol/L are associated with increased ASCVD risk, but this threshold has not been accepted universally. Elevated Lp(a) is the most common genetic dyslipidemia affecting approximately 20% of the general population. Certain currently available lipid-lowering drugs, including the proprotein convertase subtilisin/kexin type 9 therapies, produce moderate reductions in Lp(a); however, none are indicated for the treatment of elevated Lp(a). There are currently four investigational RNA-based therapeutic agents that reduce Lp(a) by 70% to 100%. Two of these agents are being evaluated for ASCVD risk reduction in adequately powered outcomes trials, with results expected in 2 to 3 years. Until such therapies become available and demonstrate favorable clinical outcomes, strategies for elevated Lp(a) primarily involve early and intensive ASCVD risk factor management.

Lipoprotein(a) and Major Adverse Cardiovascular Events in Patients With or Without Baseline Atherosclerotic Cardiovascular Disease

BACKGROUND

Lipoprotein(a) [Lp(a)] is associated with an increased risk of atherosclerotic cardiovascular disease (ASCVD). However, whether the optimal Lp(a) threshold for risk assessment should differ based on baseline ASCVD status is unknown.

OBJECTIVES

The purpose of this study was to assess the association between Lp(a) and major adverse cardiovascular events (MACE) among patients with and without baseline ASCVD.

METHODS

We studied a retrospective cohort of patients with Lp(a) measured at 2 medical centers in Boston, Massachusetts, from 2000 to 2019. To assess the association of Lp(a) with incident MACE (nonfatal myocardial infarction [MI], nonfatal stroke, coronary revascularization, or cardiovascular mortality), Lp(a) percentile groups were generated with the reference group set at the first to 50th Lp(a) percentiles. Cox proportional hazards modeling was used to assess the association of Lp(a) percentile group with MACE.

RESULTS

Overall, 16,419 individuals were analyzed with a median follow-up of 11.9 years. Among the 10,181 (62%) patients with baseline ASCVD, individuals in the 71st to 90th percentile group had a 21% increased hazard of MACE (adjusted HR: 1.21; P < 0.001), which was similar to that of individuals in the 91st to 100th group (adjusted HR: 1.26; P < 0.001). Among the 6,238 individuals without established ASCVD, there was a continuously higher hazard of MACE with increasing Lp(a), and individuals in the 91st to 100th Lp(a) percentile group had the highest relative risk with an adjusted HR of 1.93 (P < 0.001).

CONCLUSIONS

In a large, contemporary U.S. cohort, elevated Lp(a) is independently associated with long-term MACE among individuals with and without baseline ASCVD. Our results suggest that the threshold for risk assessment may be different in primary vs secondary prevention cohorts.

Lipoprotein(a): An important piece of the ASCVD risk factor puzzle across diverse populations

Elevated lipoprotein(a) (Lp[a]) is an independent, genetic risk factor for atherosclerotic cardiovascular disease (ASCVD) that impacts ~1.4 billion people globally. Generally, Lp(a) levels remain stable over time; thus, most individuals need only undergo Lp(a) testing through a non-fasting blood draw once in their lifetime, unless elevated Lp(a) is identified. Despite the convenience of the test for clinicians and patients, routine Lp(a) testing has not been widely adopted. This review provides a guide to the benefits of Lp(a) testing and solutions for overcoming common barriers in practice, including access to testing and lack of awareness. Lp(a) testing provides the opportunity to reclassify ASCVD risk and drive intensive cardiovascular risk factor management in individuals with elevated Lp(a), and to identify patients potentially less likely to respond to statins. Moreover, cascade screening can help to identify elevated Lp(a) in relatives of individuals with a personal or family history of premature ASCVD. Overall, given the profound impact of elevated Lp(a) on cardiovascular risk, Lp(a) testing should be an essential component of risk assessment by primary and specialty care providers.

Lipoprotein(a) Is Markedly More Atherogenic Than LDL: An Apolipoprotein B-Based Genetic Analysis

BACKGROUND

Lipoprotein(a) (Lp(a)) is recognized as a causal factor for coronary heart disease (CHD) but its atherogenicity relative to that of low-density lipoprotein (LDL) on a per-particle basis is indeterminate.

OBJECTIVES

The authors addressed this issue in a genetic analysis based on the fact that Lp(a) and LDL both contain 1 apolipoprotein B (apoB) per particle.

METHODS

Genome-wide association studies using the UK Biobank population identified 2 clusters of single nucleotide polymorphisms: one comprising 107 variants linked to Lp(a) mass concentration, the other with 143 variants linked to LDL concentration. In these Lp(a) and LDL clusters, the relationship of genetically predicted variation in apoB with CHD risk was assessed.

RESULTS

The Mendelian randomization-derived OR for CHD for a 50 nmol/L higher Lp(a)-apoB was 1.28 (95% CI: 1.24-1.33) compared with 1.04 (95% CI: 1.03-1.05) for the same increment in LDL-apoB. Likewise, use of polygenic scores to rank subjects according to difference in Lp(a)-apoB vs difference in LDL-apoB revealed a greater HR for CHD per 50 nmol/L apoB for the Lp(a) cluster (1.47; 95% CI: 1.36-1.58) compared with the LDL cluster (1.04; 95% CI: 1.02-1.05). From these data, we estimate that the atherogenicity of Lp(a) is approximately 6-fold (point estimate of 6.6; 95% CI: 5.1-8.8) greater than that of LDL on a per-particle basis.

CONCLUSIONS

We conclude that the atherogenicity of Lp(a) (CHD risk quotient per unit increase in particle number) is substantially greater than that of LDL. Therefore, Lp(a) represents a key target for drug-based intervention in a significant proportion of the at-risk population.

Healthy lifestyle, lipoprotein (a) levels and the risk of coronary artery disease

BACKGROUND

Lipoprotein (a) [Lp(a)] is associated with coronary artery disease (CAD). However, the role of healthy lifestyle against the risk of CAD with consideration of high Lp(a) levels remains unclear.

METHODS

This study examined 4512 participants who underwent serum Lp(a) level assessment at Kanazawa University Hospital from 2008 to March 2016. Their lifestyle habits were examined based on four questionnaires regarding dietary pattern, exercise habits, smoking status and body weight. Logistic regression analyses were performed to identify the association between healthy lifestyle and CAD independent of Lp(a) levels.

RESULTS

The Lp(a) levels were significantly associated with CAD (odds ratio [OR]: 1.12, 95% confidence interval [CI]: 1.08-1.17, p = 1.3 × 10-7 per 10 mg/dL). Under these circumstances, the lifestyle risk score was also significantly associated with CAD (OR: 1.24, 95% CI: 1.12-1.36, p = 2.4 × 10-8 ). Compared with patients with a favourable lifestyle who have Lp(a) levels of <30 mg/dL, those with an intermediate or unfavourable lifestyle were at higher risk for CAD (OR: 1.11, 95% CI: 1.02-1.20, p = 0.003 and OR: 1.40, 95% CI: 1.16-1.54, p = 3.6 × 10-5 , respectively). Further, patients with a favourable, intermediate or unfavourable lifestyle who have Lp(a) levels of ≥30 mg/dL were at high risk for CAD (OR: 1.21, 95% CI: 1.08-1.34, p = 0.0014; OR: 1.31, 95% CI: 1.14-1.48, p = 1.2 × 10-4 ; and OR: 1.81, 95% CI: 1.44-2.18, p = 2.2 × 10-7 , respectively).

CONCLUSIONS

Healthy lifestyle was associated with a lower risk of CAD regardless of Lp(a) levels.

Lipoprotein(a): a genetically determined risk factor for Cardiovascular disease

Lipoprotein(a) is a complex lipoprotein with unique characteristics distinguishing it from all the other apolipoprotein B-containing lipoprotein particles. Its lipid composition and the presence of a single molecule of apolipoprotein B per particle, render lipoprotein(a) similar to low-density lipoproteins. However, the presence of a unique, carbohydrate-rich protein termed apolipoprotein(a), linked by a covalent bond to apolipoprotein B imparts unique characteristics to lipoprotein(a) distinguishing it from all the other lipoproteins. Apolipoprotein(a) is highly polymorphic in size ranging in molecular weight from <300 KDa to >800 kDa. Both the size polymorphism and the concentration of lipoprotein(a) in plasma are genetically determined and unlike other lipoproteins, plasma concentration is minimally impacted by lifestyle modifications or lipid-lowering drugs. Many studies involving hundreds of thousands of individuals have provided strong evidence that elevated lipoprotein(a) is genetically determined and a causal risk factor for atherosclerotic cardiovascular disease. The concentration attained in adulthood is already present in children at around 5 years of age and therefore, those with elevated lipoprotein(a) are prematurely exposed to a high risk of cardiovascular disease. Despite the large number of guidelines and consensus statements on the management of lipoprotein(a) in atherosclerotic cardiovascular disease published in the last decade, lipoprotein(a) is still seldom measured in clinical settings. In this review, we provide an overview of the most important features that characterize lipoprotein(a), its role in cardiovascular disease, and the importance of adding the measurement of lipoprotein(a) for screening adults and youths to identify those at increased risk of atherosclerotic cardiovascular disease due to their elevated plasma concentration of lipoprotein(a).

Lipoprotein(a) and heart failure: a systematic review

The role of lipoprotein(a) [Lp(a)] as a possible causal risk factor for atherosclerotic artery disease and aortic valve stenosis has been well established. However, the information on the association between Lp(a) levels and heart failure (HF) is limited and controversial. The main objective of the present study was to assess the association between Lp(a) levels and HF. This systematic review was performed according to PRISMA guidelines. A literature search was performed to detect studies that evaluated the association between Lp(a) levels and HF. Eight studies, including 73,410 patients, were eligible for this research. Seven prospective or retrospective cohorts and one cross-sectional study were analyzed. Five studies analyzed populations without HF; another three included patients with HF or left ventricular dysfunction. The endpoints evaluated varied according to the study analyzed, including incident HF, HF hospitalizations, and decreased left ventricular ejection fraction. Lp(a) levels were also analyzed in different ways, including analysis of Lp(a) as a continuous or categorical variable (distinct cut-off points or percentiles). Globally, the studies included in this review found predominantly positive results. Data on some relevant subgroups, such as HF of ischemic or non-ischemic etiology or HF with or without left ventricular dysfunction, was poorly reported. This systematic review suggests that there would be a positive relationship between Lp(a) levels and HF. Given the complexity and heterogeneity of HF, new studies should be developed to clarify this topic.

Elevated Lipoprotein(a) Levels and Atrial Fibrillation: A Systematic Review

Objective

The role of lipoprotein(a) (Lp[a]) as a possibly causal risk factor for atherosclerotic cardiovascular disease has been well established. However, the clinical evidence regarding the association between Lp(a) levels and atrial fibrillation (AF) remains limited and inconsistent. This study aimed to analyze the association between elevated Lp(a) levels or single-nucleotide polymorphisms (SNPs) related to high levels of Lp(a) and AF.

Methods

This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A literature search was performed to identify studies that evaluated the association between Lp(a) levels or SNPs related to high levels of Lp(a) and AF. Observational studies with a cross-sectional, case-control, or cohort design were included in this systematic review, without limitations according to language, country, or publication type.

Results

Eleven observational studies including 1,246,817 patients were eligible for this systematic review. Two cross-sectional studies, 5 prospective/retrospective cohort studies, and 4 Mendelian randomization studies were analyzed. Two cross-sectional studies that compared Lp(a) levels between patients with and without AF showed conflicting results. Cohort studies that evaluated the incidence of AF according to Lp(a) levels showed different results: no association (3 studies), a positive association (1 study), and an inverse relationship (1 study). Finally, Mendelian randomization studies also showed heterogeneous results (positive association: 2 studies; inverse association: 1 study; no association: 1 study).

Conclusion

Although there could be an association between Lp(a) levels and AF, the results of the studies published to date are contradictory and not yet definitive. Therefore, further research should clarify this issue.

Heterogeneity of Lipoprotein(a) Levels Among Hispanic or Latino Individuals Residing in the US

Importance

Lipoprotein(a) (Lp[a]) is a genetically determined risk-enhancing factor for atherosclerotic cardiovascular disease (ASCVD). The Lp(a) distribution among the diverse Hispanic or Latino community residing in the US has not been previously described, to the authors' knowledge.

Objective

To determine the distribution of Lp(a) levels across a large cohort of diverse Hispanic or Latino adults living in the US and by key demographic groups.

Design, Setting, and Participants

The Hispanic Community Health Study/Study of Latinos (HCHS/SOL) is a prospective, population-based, cohort study of diverse Hispanic or Latino adults living in the US. At screening, participants aged 18 to 74 years were recruited between 2008 and 2011 from 4 US metropolitan areas (Bronx, New York; Chicago, Illinois; Miami, Florida; San Diego, California). HCHS/SOL included 16 415 noninstitutionalized adults recruited through probability sampling of randomly selected households. The study population represents Hispanic or Latino participants from diverse self-identified geographic and cultural backgrounds: Central American, Cuban, Dominican, Mexican, Puerto Rican, and South American. This study evaluated a subset of HCHS/SOL participants who underwent Lp(a) measurement. Sampling weights and surveys methods were used to account for HCHS/SOL sampling design. Data for this study were analyzed from April 2021 to April 2023.

Exposure

Lp(a) molar concentration was measured by a particle-enhanced turbidimetric assay with minimized sensitivity to apolipoprotein(a) size variation.

Main Outcome and Measure

Lp(a) quintiles were compared using analysis of variance among key demographic groups, including self-identified Hispanic or Latino background. Median percentage genetic ancestry (Amerindian, European, West African) were compared across Lp(a) quintiles.

Results

Lp(a) molar concentration was measured in 16 117 participants (mean [SD] age, 41 [14.8] years; 9680 female [52%]; 1704 Central American [7.7%], 2313 Cuban [21.1%], 1436 Dominican [10.3%], 6395 Mexican [39.1%], 2652 Puerto Rican [16.6%], 1051 South American [5.1%]). Median (IQR) Lp(a) level was 19.7 (7.4-59.7) nmol/L. Across Hispanic or Latino background groups, there was significant heterogeneity in median Lp(a) levels ranging from 12 to 41 nmol/L in those reporting a Mexican vs Dominican background. Median (IQR) West African genetic ancestry was lowest in the first quintile of Lp(a) level and highest in the fifth quintile (5.5% [3.4%-12.9%] and 12.1% [5.0%-32.5%]; respectively; P < .001), whereas the converse was seen for Amerindian ancestry (32.8% [9.9%-53.2%] and 10.7% [4.9%-30.7%], respectively; P < .001).

Conclusions and Relevance

Results of this cohort study suggest that differences in Lp(a) level distribution across the diverse US Hispanic or Latino population may carry important implications for the use of Lp(a) level in ASCVD risk assessment for this group. Cardiovascular outcomes data are needed to better understand the clinical impact of differences in Lp(a) levels by Hispanic or Latino background.

High lipoprotein(a) levels and mitral valve disease: A systematic review

AIMS

The role of lipoprotein(a) [Lp(a)] as a possibly causal risk factor for atherosclerotic artery disease and aortic valve stenosis has been well established. However, the information available on the association between Lp(a) levels and mitral valve disease is limited and controversial. The main objective of the present study was to assess the association between Lp(a) levels and mitral valve disease.

DATA SYNTHESIS

This systematic review was performed according to PRISMA guidelines (PROSPERO CRD42022379044). A literature search was performed to detect studies that evaluated the association between Lp(a) levels or single-nucleotide polymorphisms (SNPs) related to high levels of Lp(a) and mitral valve disease, including mitral valve calcification and valve dysfunction. Eight studies including 1,011,520 individuals were considered eligible for this research. The studies that evaluated the association between Lp(a) levels and prevalent mitral valve calcification found predominantly positive results. Similar findings were reported in two studies that evaluated the SNPs related to high levels of Lp(a). Only two studies evaluated the association of Lp(a) and mitral valve dysfunction, showing contradictory results.

CONCLUSIONS

This research showed disparate results regarding the association between Lp(a) levels and mitral valve disease. The association between Lp(a) levels and mitral valve calcification seems more robust and is in line with the findings already demonstrated in aortic valve disease. New studies should be developed to clarify this topic.

Clinical Trial Design for Lipoprotein(a)-Lowering Therapies: JACC Focus Seminar 2/3

Lipoprotein(a) [Lp(a)] is a source of residual risk in patients with atherosclerotic cardiovascular disease (ASCVD). Clinical trials of fully human monoclonal antibodies targeting proprotein convertase subtilisin kexin 9 have shown that reductions in Lp(a) concentrations may be a predictor of event reduction with this class of cholesterol-lowering therapy. With the advent of selective therapies targeting Lp(a) such as antisense oligonucleotides, small-interfering RNA-based therapies, and gene editing, lowering of Lp(a) may lead to reduction in ASCVD. The phase 3 Lp(a)HORIZON (Assessing the Impact of Lipoprotein(a) Lowering with TQJ230 on Major Cardiovascular Events in Patients With CVD) outcomes trial is currently testing the effect of pelacarsen, an antisense oligonucleotide, on ASCVD risk. Olpasiran is a small-interfering RNA that is in a phase 3 clinical trial. As these therapies enter clinical trials, challenges in trial design will have to be addressed to optimize patient selection and outcomes.

Efficacy and safety of pelacarsen in lowering Lp(a) in healthy Japanese subjects

BACKGROUND

Pelacarsen is a liver-targeted antisense oligonucleotide that potently lowers lipoprotein(a) [Lp(a)] levels. Its safety and efficacy in diverse populations has not been extensively studied.

OBJECTIVE

To assess the effect of pelacarsen, including monthly dosing of 80 mg, in subjects of Japanese ancestry.

METHODS

A randomized double-blind, placebo-controlled, study was performed in 29 healthy Japanese subjects treated with single ascending doses (SAD) of pelacarsen 20, 40 and 80 mg subcutaneously or multiple doses (MD) of pelacarsen 80 mg monthly for 4 doses. The primary objective was to assess the safety and tolerability in healthy Japanese subjects; secondary objectives to assess the pharmacokinetics of pelacarsen; and exploratory objective to determine the effect of pelacarsen on plasma Lp(a) levels.

RESULTS

No serious adverse events or clinically relevant abnormalities in any laboratory parameters were noted. In the MD cohort, mean plasma concentrations of pelacarsen peaked at ∼4 hours and declined in a bi-exponential manner thereafter. In the SAD cohorts, the placebo-corrected least-square mean (PCLSM) percent changes in Lp(a) at Day 30 were: -55.4% (p=0.0008), -58.9% (p=0.0003) and -73.7% (p<0.0001) for the 20 mg, 40 mg, and 80 mg pelacarsen-treated groups, respectively. In the MD cohort, the PCLSM at Days 29, 85, 113, 176 and 204 were -84.0% (p=0.0003), -106.2% (p<0.0001), -70.0 (p<0.0001), -80.0% (p=0.0104) and -55.8% (p=0.0707), respectively.

CONCLUSIONS

Pelacarsen demonstrates an acceptable safety and tolerability profile and potently lowers plasma levels of Lp(a) in healthy Japanese subjects, including with the 80 mg monthly dose being evaluated in the Lp(a) HORIZON trial.