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

Distinct lipoprotein contributions to valvular heart disease: Insights from genetic analysis

BACKGROUND

The per-particle pathogenicity of very-low-density lipoprotein (VLDL) and lipoprotein(a) [Lp(a)] with risk of valvular heart diseases (VHD) other than aortic stenosis compared with low-density lipoprotein (LDL) remains unclear.

METHODS

Single-nucleotide polymorphism specific clusters associated with LDL cholesterol (LDL-C), VLDL cholesterol (VLDL-C) and Lp(a) were identified. The relationships of genetically predicted variation in apolipoprotein B (apoB) in these lipoproteins with risk of VHD and its major types (aortic stenosis, aortic regurgitation, and mitral regurgitation) were evaluated to determine the comparative pathogenicity by Mendelian randomization (MR) analyses.

RESULTS

The VHD odds ratio (OR) per 1 g/L higher apoB was 1.09 [95 % confidence interval (CI) 1.04-1.15] in LDL vs. 1.45 (95 % CI 1.25-1.69) in VLDL vs. 2.71 (95 % CI 1.92-3.82) in Lp(a) based on the cluster-based MR analyses. The polygenic scores for each lipoprotein weighted by apoB similarly showed a greater OR of VHD per 1 g/L apoB in VLDL [1.20 (95 % CI 1.06-1.37)] and in Lp(a) [2.54, (95 % CI 1.95-3.32)] compared with that in LDL [1.05 (95 % CI 1.01-1.08)]. Multivariable MR analyses further revealed the strong effects of VLDL-C and Lp(a) on VHD risk independent of LDL-C. In addition, significant associations between Lp(a) and all three major types of VHD were observed, while LDL and VLDL had no impact on aortic and mitral regurgitation.

CONCLUSIONS

VLDL and Lp(a) appear to have significantly greater per-particle pathogenicity in VHD compared to LDL. The distinct impacts of lipoproteins on different VHD subtypes suggest the inadequacy of just focusing on LDL-lowering treatment for valve disorders.

Apolipoprotein B-containing lipoproteins in atherogenesis

Apolipoprotein B (apoB) is the main structural protein of LDLs, triglyceride-rich lipoproteins and lipoprotein(a), and is crucial for their formation, metabolism and atherogenic properties. In this Review, we present insights into the role of apoB-containing lipoproteins in atherogenesis, with an emphasis on the mechanisms leading to plaque initiation and growth. LDL, the most abundant cholesterol-rich lipoprotein in plasma, is causally linked to atherosclerosis. LDL enters the artery wall by transcytosis and, in vulnerable regions, is retained in the subendothelial space by binding to proteoglycans via specific sites on apoB. A maladaptive response ensues. This response involves modification of LDL particles, which promotes LDL retention and the release of bioactive lipid products that trigger inflammatory responses in vascular cells, as well as adaptive immune responses. Resident and recruited macrophages take up modified LDL, leading to foam cell formation and ultimately cell death due to inadequate cellular lipid handling. Accumulation of dead cells and cholesterol crystallization are hallmarks of the necrotic core of atherosclerotic plaques. Other apoB-containing lipoproteins, although less abundant, have substantially greater atherogenicity per particle than LDL. These lipoproteins probably contribute to atherogenesis in a similar way to LDL but might also induce additional pathogenic mechanisms. Several targets for intervention to reduce the rate of atherosclerotic lesion initiation and progression have now been identified, including lowering plasma lipoprotein levels and modulating the maladaptive responses in the artery wall.

Lp(a): A Clinical Review

Elevated lipoprotein(a) (Lp[a]) is a genetically determined cardiovascular risk factor, linked to both atherosclerotic cardiovascular disease and aortic stenosis. Elevated Lp(a) is widely prevalent, and consequently, several cardiovascular societies now recommend performing Lp(a) screening at least once in all adults. While there are presently no approved drugs specifically aimed at lowering Lp(a), several promising candidates are currently in the drug development pipeline, and many of these are now undergoing late phase clinical trials. In this comprehensive review, we outline Lp(a) biology and genetics, describe Lp(a)'s relationship to various cardiovascular clinical phenotypes of interest, highlight novel Lp(a)-lowering therapies, and outline what role these may have in future clinical practice.

Machine-Learning Assisted Screening with FIND FH® for Familial Hypercholesterolemia Among Youth

Although the American Academy of Pediatrics recommends universal lipid screening among children to find cases of familial hypercholesterolemia, such screening is rarely performed. We report the first clinical use of a novel machine learning model (FIND FH®) to identify youth at increased risk of familial hypercholesterolemia and results from associated outreach.

Residual lipoprotein(a)-associated risk in patients with stroke or transient ischemic attack

BACKGROUND AND AIMS

Lipoprotein (a) [Lp(a)] is a genetically determined risk factor for atherosclerotic cardiovascular diseases. This study aimed to evaluate the association of serum Lp(a) levels with the risk of residual vascular event risk after stroke or transient ischemic attack (TIA) in the Japanese population.

METHODS

In this prospective observational study, 533 patients (mean age, 70.7 years; female, 41.8 %) with ischemic stroke (n = 496) or high-risk TIA (n = 37) were consecutively enrolled within 1 week of onset and followed up for 1 year. Patients were divided into 2 groups according to the median baseline Lp(a) levels: (i) low (≤15 mg/dL, n = 270) and (ii) high (>15 mg/dL, n = 263) Lp(a) groups. The primary endpoint was a composite of major adverse cardiovascular events (MACEs), including nonfatal stroke, nonfatal acute coronary syndrome, and vascular death.

RESULTS

Compared to patients with Lp(a) ≤15 mg/dL, those with Lp(a) > 15 mg/dL were more likely to have extracranial carotid artery stenosis (8.8 % versus 15.2 %; p = 0.024) and a history of coronary artery disease (7.8 % versus 14.1 %; p = 0.019). Elevated Lp(a) levels were independently associated with an increased risk of MACE (annual rate, 10.7 % versus 19.1 %; log-rank p = 0.009; adjusted hazard ratio, 1.68; 95 % confidence interval, 1.03-2.72; p = 0.037). When patients were classified according to the etiologic subtype of the index event, elevated Lp(a) was a significant predictor of MACE in patients with atherothrombotic stroke (annual rate, 14.0 % versus 25.8 %; log-rank p = 0.041), but not in those with small vessel disease, cardioembolism, or cryptogenic stroke.

CONCLUSIONS

Elevated Lp(a) levels >15 mg/dL in Japanese patients with stroke are associated with extracranial carotid stenosis and a higher risk of MACE. The measurement of Lp(a) levels helped refine the risk assessment of patients with stroke or TIA.

Evolving concepts of low-density lipoprotein: From structure to function

BACKGROUND

Low-density lipoprotein (LDL) is a central player in atherogenesis and has long been referred to as 'bad cholesterol.' However, emerging evidence indicates that LDL functions in multifaceted ways beyond cholesterol transport that include roles in inflammation, immunity, and cellular signaling. Understanding LDL's structure, metabolism and function is essential for advancing cardiovascular disease research and therapeutic strategies.

METHODS

This narrative review examines the history, structural properties, metabolism and functions of LDL in cardiovascular health and disease. We analyze key milestones in LDL research, from its early identification to recent advancements in molecular biology and omics-based investigations. Structural and functional insights are explored through imaging, proteomic analyses and lipidomic profiling, providing a deeper understanding of LDL heterogeneity.

RESULTS

Low-density lipoprotein metabolism, from biosynthesis to receptor-mediated clearance, plays a crucial role in lipid homeostasis and atherogenesis. Beyond cholesterol transport, LDL contributes to plaque inflammation, modulates adaptive immunity and regulates cellular signaling pathways. Structural studies reveal its heterogeneous composition, which influences its pathogenic potential. Evolving perspectives on LDL redefine its clinical significance, affecting cardiovascular risk assessment and therapeutic interventions.

CONCLUSIONS

A holistic understanding of LDL biology challenges traditional perspectives and underscores its complexity in cardiovascular health. Future research should focus on further elucidating LDL's structural and functional diversity to refine risk prediction models and therapeutic strategies, ultimately improving cardiovascular outcomes.

Lepodisiran - A Long-Duration Small Interfering RNA Targeting Lipoprotein(a)

BACKGROUND

Elevated lipoprotein(a) concentrations are associated with atherosclerotic cardiovascular disease. The safety and efficacy of lepodisiran, an extended-duration, small interfering RNA targeting hepatic synthesis of lipoprotein(a), are unknown.

METHODS

We randomly assigned participants in a 1:2:2:2:2 ratio to receive lepodisiran at a dose of 16 mg, 96 mg, or 400 mg at baseline and again at day 180, lepodisiran at a dose of 400 mg at baseline and placebo at day 180, or placebo at baseline and at day 180, all administered by subcutaneous injection. Data from the two groups that received lepodisiran at a dose of 400 mg at baseline were pooled for the primary analysis. The primary end point was the time-averaged percent change from baseline in the serum lipoprotein(a) concentration (lepodisiran difference from placebo [i.e., placebo-adjusted]) during the period from day 60 to day 180.

RESULTS

A total of 320 participants underwent randomization; the median baseline lipoprotein(a) concentration was 253.9 nmol per liter. The placebo-adjusted time-averaged percent change from baseline in the serum lipoprotein(a) concentration from day 60 to day 180 was -40.8 percentage points (95% confidence interval [CI], -55.8 to -20.6) in the 16-mg lepodisiran group, -75.2 percentage points (95% CI, -80.4 to -68.5) in the 96-mg group, and -93.9 percentage points (95% CI, -95.1 to -92.5) in the pooled 400-mg groups. The corresponding change from day 30 to day 360 was -41.2 percentage points (95% CI, -55.4 to -22.4), -77.2 percentage points (95% CI, -81.8 to -71.5), -88.5 percentage points (95% CI, -90.8 to -85.6), and -94.8 percentage points (95% CI, -95.9 to -93.4) in the 16-mg, 96-mg, 400-mg-placebo, and 400-mg-400-mg dose groups, respectively. Serious adverse events, none of which were deemed by investigators to be related to lepodisiran or placebo, occurred in 35 participants. Dose-dependent, generally mild injection-site reactions occurred in up to 12% (8 of 69) of the participants in the highest lepodisiran dose group.

CONCLUSIONS

Lepodisiran reduced mean serum concentrations of lipoprotein(a) from 60 to 180 days after administration. (Funded by Eli Lilly; ALPACA ClinicalTrials.gov number, NCT05565742.).

Elevated plasma concentrations of lipoprotein (a) are associated with cardiovascular diseases in patients with early-onset type 2 diabetes mellitus

Objective

To ascertain whether vascular complications and high lipoprotein (a) [Lp(a)] concentrations are related in individuals with early-onset type 2 diabetes mellitus (T2DM).

Methods

This observational cross-sectional study included 591 individuals with early-onset T2DM who were divided into four groups based on Lp(a) values which was measured using immunoturbidimetry and presented as mg/dL: high, >50; intermediate, 30≤Lp(a)<50; low, 10≤Lp(a)<30; and very low, <10. The relationship between the risk of vascular complications and Lp(a) level was examined using a logistic regression model.

Results

The median age of onset for individuals with early-onset T2DM (n=591) was 37 years, duration of diabetes was 12 years, and glycated hemoglobin (HbA1c) level was 8.8%. The median Lp(a) was 10.40 (4.80-21.80) mg/dL, and Lp(a) concentration did not correlate with age, sex, or glycemic control (P>0.05). Individuals in the low Lp(a) (OR=2.12, 95% CI 1.17-3.84, P<0.05), intermediate Lp(a) (OR=2.76, 95% CI 1.10-6.98, P<0.05) and high Lp(a) (OR=4.79, 95% CI 2.03-11.31, P<0.01) groups had an increased risk of coronary heart disease (CHD) compared with those in the very low Lp(a) group after adjustment. Nevertheless, among individuals with early-onset T2DM, there was no correlation between Lp(a) concentration and the risk of cerebrovascular disease (CVL) and microvascular complications (P>0.05).

Conclusions

In patients with early-onset T2DM, Lp(a) concentration was independently associated with CHD. Lp(a) testing is essential to determine who has a latent high risk of CHD among patients with early-onset T2DM.

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.

ApoB-containing lipoproteins: count, type, size, and risk of coronary artery disease

BACKGROUND AND AIMS

Apolipoprotein B concentration reflects the number of atherogenic lipoproteins and is recognized as a key lipid risk marker. Whether the type or size of apoB particle (apoB-P) adds predictive value for coronary artery disease (CAD) remains unclear.

METHODS

A prospective analysis of 207 368 UK Biobank participants with comprehensive lipoprotein profiling and no prior history of atherosclerotic disease, diabetes, or active lipid-lowering therapy was conducted. Multivariable-adjusted Cox regression models were used to examine the association between each of the following lipid parameters with incident CAD: (i) nuclear magnetic resonance-measured apoB-P, (ii) concentrations of individual lipoprotein classes [very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL)], (iii) size subclasses, (iv) average particle diameter, and (v) immunoassay-measured lipoprotein(a) [Lp(a)].

RESULTS

A one standard deviation (SD) increase in apoB-P was associated with a 33% higher CAD risk [hazard ratio (HR): 1.33, 95% CI: 1.30-1.36]. Although VLDL particles were observed to carry a higher per-particle risk (HR per 100 nmol/L: 1.22, 1.11-1.34) compared with LDL (HR per 100 nmol/L: 1.07, 1.05-1.08), this difference was counterbalanced after considering relative particle abundance (LDL 91% vs VLDL 9% of total apoB-P). Thus the respective HR per 1-SD were 1.09 (1.05-1.14) and 1.24 (1.19-1.30). Particle diameter or size subclasses were not associated with CAD after apoB-P adjustment. The association of Lp(a) was robust even after apoB-P adjustment (HR:1.18, 1.16-1.20) and added independent prognostic value for CAD (area under curve: 0.769 vs 0.774, P < .001).

CONCLUSIONS

Lipid-related atherosclerotic risk is most accurately reflected by the total count of apoB-P and is largely unaffected by the major particle type (VLDL, LDL) or size. Elevated count of Lp(a) adds additional risk, and thus adequate assessment of atherogenic risk from dyslipidemia is best accomplished by consideration of both apoB-P and Lp(a) concentrations.

Modern therapy of patients with lupus erythematosus must include appropriate management of their heightened rates of atherosclerotic cardiovascular events: a literature update

Atherosclerotic cardiovascular disease (ASCVD) remains the biggest killer of patients with lupus erythematosus (LE) and the general non-autoimmune population. In this literature update on LE and ASCVD, we focused on published work since our earlier review article, meaning from 2021 to the present, with an emphasis on cutaneous LE. Several themes emerged. First, new work shows that patients with lupus still exhibit a high burden of conventional risk factors for ASCVD events. Second, recent studies continue to implicate possible effects of lupus disease activity to worsen rates of ASCVD events beyond predictions from conventional risk factors. Third, new work on estimating the risk of future ASCVD events in patients with lupus supports arterial-wall imaging, inclusion of lupus-specific factors, estimators of ASCVD event risk that take lupus status into account and considering lupus as a diabetes equivalent or even as a diabetes-plus-smoking equivalent in this context. Technologies for arterial-wall imaging continue to improve and will likely play an increasing role in ASCVD assessment and management. Fourth, purported cardiovascular benefits from certain disease-modifying antirheumatic drugs such as antimalarials have become less clear. Fifth, earlier treatment of atherosclerosis, which is a lifelong disease, can be accomplished with diet, exercise, smoking cessation and new classes of safe and effective medications for lipid-lowering and blood pressure control. Benefits on subclinical arterial disease by imaging and on ASCVD events have been reported, supporting the concept that ASCVD is eminently manageable in this autoimmune condition. Sixth, despite the heightened risk for ASCVD events in patients with lupus, available therapeutic approaches remain unused or underused and, accordingly, event rates remain high.Raising awareness among patients and healthcare providers about ASCVD assessment and management in patients with LE is essential. Greater vigilance is needed to prevent ASCVD events in patients with lupus by addressing dyslipidaemias, hypertension, smoking, obesity and physical inactivity.

Elevated lipoprotein(a) is not linked to coronary artery calcification incidence or progression

AIMS

Lipoprotein(a) [Lp(a)] is a genetically determined, independent risk factor for atherosclerotic cardiovascular disease. However, its role in coronary artery calcification (CAC) remains unclear. We aimed to determine whether Lp(a) levels are associated with the incidence and progression of CAC.

METHODS AND RESULTS

We conducted a longitudinal cohort study (2015-22) of 41 929 adults (aged ≥30 years) who underwent baseline Lp(a) measurement and CAC assessment via multi-detector computed tomography. Participants were stratified into those with baseline CAC = 0 (n = 32 338) and CAC > 0 (n = 9591). Outcomes were analysed according to Lp(a) quintiles and clinically relevant categories (<30, 30-50, 50-100, ≥ 100 mg/dL). Cox proportional hazards models estimated hazard ratios (HRs) for incident CAC (CAC > 0) among those with CAC = 0 (median follow-up, 4.04 years). Linear mixed-effects models evaluated CAC progression among those with CAC > 0 (median follow-up, 3.78 years). All models were adjusted for cardiovascular risk factors. Among participants with CAC = 0 (mean age, 40.94 ± 5.81 years; 85.69% men), neither Lp(a) quintiles nor clinical categories were significantly associated with incident CAC [HR for highest vs. second quintile: 0.998 (95% confidence interval, CI, 0.90-1.10); HR for ≥100 vs. <30 mg/dL: 0.83 (95% CI, 0.57-1.23)]. Among those with CAC > 0 (mean age, 45.99 ± 7.20 years; 94.90% men), CAC progression did not differ materially across Lp(a) quintiles or clinical thresholds.

CONCLUSION

Elevated Lp(a) levels were not associated with new-onset CAC or progression of existing CAC in this large longitudinal cohort.

Therapeutic PCSK9 targeting: Inside versus outside the hepatocyte?

As a major regulator of LDL receptor (LDLR) activity and thus of LDL-cholesterol (LDL-C) levels, proprotein convertase subtilisin/kexin type 9 (PCSK9) represents an obvious therapeutic target for lipid lowering. The PCSK9 inhibitors, alirocumab and evolocumab, are human monoclonal antibodies (mAbs) that act outside the cell by complexing circulating PCSK9 and thus preventing its binding to the LDLR. In contrast, inclisiran, a small interfering RNA (siRNA), inhibits hepatic synthesis of PCSK9, thereby resulting in reduced amounts of the protein inside and outside the cell. Both approaches result in decreased plasma LDL-C concentrations and improved cardiovascular outcomes. Marginally superior LDL-C reduction (≈ 60 %) is achieved with mAbs as compared to the siRNA (≈ 50 %); head-to-head comparisons are required to confirm between-class differences in efficacy. Both drug classes have shown variability in LDL-C lowering response between individuals in waterfall analyses. Whereas mAb-mediated inhibition leads to a compensatory increase in plasma PCSK9 levels, siRNA treatment reduces them. These agents differ in their pharmacokinetic and pharmacodynamic features, which may translate into distinct clinical opportunities under acute (e.g. acute coronary syndromes) as compared to chronic conditions. Both drug classes provide additional reduction in LDL-C levels (up to 50 %) beyond those achieved with statin therapy, facilitating attainment of guideline-recommended LDL-C goals in high and very high-risk patients. Additional PCSK9 inhibitors, including an oral macrocyclic peptide, a small PCSK9 binding protein and a novel small molecule, plus hepatic gene editing of PCSK9, are under development. This review critically appraises pharmacological strategies to target PCSK9 either inside or outside the cell.

Discordance analyses comparing LDL cholesterol, Non-HDL cholesterol, and apolipoprotein B for cardiovascular risk estimation

For decades, studies have tried to identify the cholesterol marker that best reflects risk of atherosclerotic cardiovascular disease(ASCVD). Comparing low-density-lipoprotein(LDL) cholesterol, non-high-density-lipoprotein(non-HDL) cholesterol, and apolipoprotein B(apoB) as ASCVD risk markers has been challenged by high correlation between them. Thus, discordance analyses, directly addressing disagreements between the cholesterol markers, have emerged. Approaches adopted to define discordance originate in one of three methods: discordance by cut-points, discordance by percentiles, or discordance by residuals. Commonly, concordant lipid levels serve as reference examining the association between discordant lipid levels with risk of ASCVD. Importantly, concordant reference groups present heterogeneity of clinical relevance across different discordance methods as concordant low lipid levels associate with lowest ASCVD risk while concordant high lipid levels associate with highest risk. Thus, results from different discordance approaches cannot be directly compared. Moreover, discordance between cholesterol markers is more frequently seen in individuals treated with lipid-lowering medication than in individuals not treated with lipid-lowering medication. Accordingly, studies performing discordance analyses have reported inconsistent and even conflicting results. Discordance by cut-points appears the most intuitive and clinically applicable method; results from these analyses suggest that elevated LDL cholesterol, non-HDL cholesterol, or apoB levels in individuals not treated with lipid-lowering medication confer increased ASCVD risk while in individuals treated with lipid-lowering medication, elevated non-HDL cholesterol and apoB levels best indicate residual risk. Results from discordance analyses comparing LDL cholesterol, non-HDL cholesterol, and apoB in risk of ASCVD as well as complexities of discordance analyses and considerations regarding interpretations are discussed in this review.

Leveraging drug-target Mendelian randomization for tailored lipoprotein-lipid lowering

PURPOSE OF REVIEW

The study of naturally occurring genetic variation in human populations has laid the foundation for proprotein converts subtilisin/kexin type 9 inhibitors, and more recently new classes of lipid-lowering drugs such as lipoprotein(a) inhibitors and lipoprotein lipase pathway activators. These emerging therapies lower plasma lipoprotein-lipid levels that are not adequately managed by traditional low-density lipoprotein (LDL) cholesterol-lowering medications. By targeting different risk factors, these therapies could help manage the important residual cardiovascular risk of LDL cholesterol medications.

RECENT FINDINGS

We review the latest insights into the pharmacological and genetic modulation of these new therapeutic targets. We highlight that the drugs remarkably recapitulate the lipid effects observed in genetic studies. In addition to lowering lipoprotein-lipid levels, robust genetic evidence support that these drugs may prevent cardiometabolic outcomes.

SUMMARY

Emerging lipid-lowering therapies could launch a new era for preventive medicine in which treatments are optimally tailored to patient's lipoprotein-lipid profiles.

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.

Synergistic effects of lipoprotein (a) and fibrinogen on carotid plaque in patients with coronary artery disease

BACKGROUND

Elevated lipoprotein (a) [Lp (a)] and fibrinogen (Fib) are important factors contributing to the pathogenesis of atherosclerosis. Carotid plaque is a manifestation of carotid atherosclerosis, and previous studies have shown that Fib has a synergistic effect on Lp (a)-induced events. However, the effect of the combined action of Lp (a) and fibrinogen on carotid plaque has not been elucidated.

METHODS

This was a cross-sectional study that screened a total of 3913 patients who attended the First Affiliated Hospital of Xinjiang Medical University with confirmed diagnosis of coronary artery disease (CAD) and carotid ultrasonography during 2019-2024. General clinical information, physical examination data, and laboratory tests were collected from the patients. Based on the results of carotid ultrasonography, the patients were divided into a group with carotid plaque (1123 cases) and a group without carotid plaque (2790 cases). Multifactorial logistic regression analysis was used to explore the correlation between Lp (a) and Fib levels and carotid plaque and the interrelationship between them.

RESULTS

A total of 3913 patients were included, including 2666 males and 1247 females, and the incidence of carotid plaque was 28.7%, with significant differences in Lp (a) and Fib levels between the two groups with and without carotid plaque (P < 0.05) and a significant interaction effect. Multiple logistic regression analysis showed that for every tenfold increase in plasma Lp (a) levels (i.e., an increase of one logarithmic unit), the incidence of carotid plaque could increase by about 32% or so. After stratified analysis for age and sex, it was observed that carotid plaque was significantly associated with plasma Lp (a) levels in men and in patients aged < 60 years (male: OR = 1.301, 95% CI 1.051-1.611; age < 60 years: OR = 1.373, 95% CI 1.076-1.753). Plasma Fib levels were associated with carotid plaque in patients of different sexes and age groups, and there was a significant synergistic effect of Lp (a) and Fib on carotid plaque (Pinteraction < 0.05).

CONCLUSIONS

Elevated levels of Lp (a) and Fib are independent risk factors for combined carotid plaque in patients with coronary artery disease, and there is a synergistic effect of both on carotid plaque. Therefore, plasma Lp (a) and Fib levels of patients should be focused on for better treatment of carotid plaque and prevention of ischemic stroke.

Lipoprotein(a) as a Causal Risk Factor for Cardiovascular Disease

Purpose of Review

Lipoprotein(a) [Lp(a)], an atherogenic low-density lipoprotein cholesterol (LDL-C)-like molecule, has emerged as an important risk factor for the development of atherosclerotic cardiovascular disease (ASCVD). This review summarizes the evidence supporting Lp(a) as a causal risk factor for ASCVD and calcific aortic valve stenosis (CAVS).

Recent Findings

Lp(a) is largely (~ 90%) genetically determined and approximately 20% of the global population has elevated Lp(a). The unique structure of Lp(a) leads to proatherogenic, proinflammatory, and antifibrinolytic properties. Data from epidemiological, genome-wide association, Mendelian randomization, and meta-analyses have shown a clear association between Lp(a) and ASCVD, as well as CAVS. There are emerging data on the association between Lp(a) and ischemic stroke, peripheral arterial disease, and heart failure; however, the associations are not as strong.

Summary

Several lines of evidence support Lp(a) as a causal risk factor for ASCVD and CAVS. The 2024 National Lipid Association guidelines, 2022 European Atherosclerosis Society, and 2021 Canadian Cardiology Society guidelines recommend testing Lp(a) once in all adults to guide primary prevention efforts. Further studies on cardiovascular outcomes with Lp(a) targeted therapies will provide more insight on causal relationship between Lp(a) and cardiovascular disease.

The Interplay Between Immunity, Inflammation and Endothelial Dysfunction

The endothelium is pivotal in multiple physiological processes, such as maintaining vascular homeostasis, metabolism, platelet function, and oxidative stress. Emerging evidence in the past decade highlighted the immunomodulatory function of endothelium, serving as a link between innate, adaptive immunity and inflammation. This review examines the regulation of the immune-inflammatory axis by the endothelium, discusses physiological immune functions, and explores pathophysiological processes leading to endothelial dysfunction in various metabolic disturbances, including hyperglycemia, obesity, hypertension, and dyslipidaemia. The final section focuses on the novel, repurposed, and emerging therapeutic targets that address the immune-inflammatory axis in endothelial dysfunction.

A Comprehensive Review of the Genetics of Dyslipidemias and Risk of Atherosclerotic Cardiovascular Disease

Dyslipidemias are often diagnosed based on an individual's lipid panel that may or may not include Lp(a) or apoB. But these values alone omit key information that can underestimate risk and misdiagnose disease, which leads to imprecise medical therapies that reduce efficacy with unnecessary adverse events. For example, knowing whether an individual's dyslipidemia is monogenic can granularly inform risk and create opportunities for precision therapeutics. This review explores the canonical and non-canonical causes of dyslipidemias and how they impact atherosclerotic cardiovascular disease (ASCVD) risk. This review emphasizes the multitude of genetic causes that cause primary hypercholesterolemia, hypertriglyceridemia, and low or elevated high-density lipoprotein (HDL)-cholesterol levels. Within each of these sections, this review will explore the evidence linking these genetic conditions with ASCVD risk. Where applicable, this review will summarize approved therapies for a particular genetic condition.

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.

Lipoprotein(a) Atherosclerotic Cardiovascular Disease Risk Score Development and Prediction in Primary Prevention From Real-World Data

BACKGROUND

Lipoprotein(a) [Lp(a)] is a predictor of atherosclerotic cardiovascular disease (ASCVD); however, there are few algorithms incorporating Lp(a), especially from real-world settings. We developed an electronic health record (EHR)-based risk prediction algorithm including Lp(a).

METHODS

Utilizing a large EHR database, we categorized Lp(a) cut points at 25, 50, and 75 mg/dL and constructed 10-year ASCVD risk prediction models incorporating Lp(a), with external validation in a pooled cohort of 4 US prospective studies. Net reclassification improvement was determined among borderline-intermediate risk patients.

RESULTS

We included 5902 patients aged ≥18 years (mean age 48.7±16.7 years, 51.2% women, and 7.7% Black). Our EHR model included Lp(a), age, sex, Black race/ethnicity, systolic blood pressure, total and high-density lipoprotein cholesterol, diabetes, smoking, and hypertension medication. Over a mean follow-up of 6.8 years, ASCVD event rates (per 1000 person-years) ranged from 8.7 to 16.7 across Lp(a) groups. A 25 mg/dL increment in Lp(a) was associated with an adjusted hazard ratio of 1.23 (95% CI, 1.10-1.37) for composite ASCVD. Those with Lp(a) ≥75 mg/dL had an 88% higher risk of ASCVD (hazard ratio, 1.88 [95% CI, 1.30-2.70]) and more than double the risk of incident stroke (hazard ratio, 2.55 [95% CI, 1.54-4.23]). C-statistics for our EHR and EHR+Lp(a) models in our EHR training data set were 0.7475 and 0.7556, respectively, with external validation in our pooled cohort (n=21 864) of 0.7350 and 0.7368, respectively. Among those at borderline/intermediate risk, the net reclassification improvement was 21.3%.

CONCLUSIONS

We show the feasibility of developing an improved ASCVD risk prediction model incorporating Lp(a) based on a real-world adult clinic population. The inclusion of Lp(a) in ASCVD prediction models can reclassify risk in patients who may benefit from more intensified ASCVD prevention efforts.

Genetically predicted lipoprotein(a) associates with coronary artery plaque severity independent of low-density lipoprotein cholesterol

AIMS

Elevated lipoprotein(a) [Lp(a)] is a causal risk factor for atherosclerotic cardiovascular disease, but the mechanisms of risk are debated. Studies have found inconsistent associations between Lp(a) and measurements of atherosclerosis. We aimed to assess the relationship between Lp(a), low-density lipoprotein cholesterol (LDL-C), and coronary artery plaque severity.

METHODS AND RESULTS

The study population consisted of participants of the Million Veteran Program who have undergone an invasive angiogram. The primary exposure was genetically predicted Lp(a) estimated by a polygenic score. Genetically predicted LDL-C was also assessed for comparison. The primary outcome was coronary artery plaque severity categorized as normal, non-obstructive disease, one-vessel disease, two-vessel disease, and three-vessel or left main disease. Among 18 927 adults of genetically inferred European ancestry and 4039 adults of genetically inferred African ancestry, we observed consistent associations between genetically predicted Lp(a) and obstructive coronary plaque, with effect sizes trending upward for increasingly severe categories of disease. Associations were independent of risk factors, clinically measured LDL-C and genetically predicted LDL-C. However, we did not find strong or consistent evidence for an association between genetically predicted Lp(a) and risk for non-obstructive plaque.

CONCLUSION

Genetically predicted Lp(a) is positively associated with coronary plaque severity independent of LDL-C, consistent with Lp(a) promoting atherogenesis. However, the effects of Lp(a) may be greater for progression of plaque to obstructive disease than for the initial development of non-obstructive plaque. A limitation of this study is that Lp(a) was estimated using genetic markers and could not be directly assayed nor could apo(a) isoform size.

Early-onset atherosclerotic cardiovascular disease

Recent trends indicate a concerning increase in early-onset atherosclerotic cardiovascular disease (ASCVD) among younger individuals (men aged <55 years women aged <65 years). These findings highlight the pathobiology of ASCVD as a disease process that begins early in life and underscores the need for more tailored screening methods and preventive strategies. Increasing attention has been placed on the growing burden of traditional cardiometabolic risk factors in young individuals while also recognizing unique factors that mediate risk of pre-mature atherosclerosis in this demographic such as substance use, socioeconomic disparities, adverse pregnancy outcomes, and chronic inflammatory states that contribute to the increasing incidence of early ASCVD. Additionally, mounting evidence has pointed out significant disparities in the diagnosis and management of early ASCVD and cardiovascular outcomes based on sex and race. Moving towards a more personalized approach, emerging data and technological developments using diverse tools such as polygenic risk scores and coronary artery calcium scans have shown potential in earlier detection of ASCVD risk. Thus, we review current evidence on causal risk factors that drive the increase in early ASCVD and highlight emerging tools to improve ASCVD risk assessment in young individuals.

Oral Muvalaplin for Lowering of Lipoprotein(a): A Randomized Clinical Trial

Importance

Muvalaplin inhibits lipoprotein(a) formation. A 14-day phase 1 study demonstrated that muvalaplin was well tolerated and reduced lipoprotein(a) levels up to 65%. The effect of longer administration of muvalaplin on lipoprotein(a) levels in individuals at high cardiovascular risk remains uncertain.

Objectives

To determine the effect of muvalaplin on lipoprotein(a) levels and to assess safety and tolerability.

Design, Setting, and Participants

Phase 2, placebo-controlled, randomized, double-blind trial enrolling 233 participants with lipoprotein(a) concentrations of 175 nmol/L or greater with atherosclerotic cardiovascular disease, diabetes, or familial hypercholesterolemia at 43 sites in Asia, Europe, Australia, Brazil, and the United States between December 10, 2022, and November 22, 2023.

Interventions

Participants were randomized to receive orally administered muvalaplin at dosages of 10 mg/d (n = 34), 60 mg/d (n = 64), or 240 mg/d (n = 68) or placebo (n = 67) for 12 weeks.

Main Outcomes and Measures

The primary end point was the placebo-adjusted percentage change from baseline in lipoprotein(a) molar concentration at week 12, using an assay to measure intact lipoprotein(a) and a traditional apolipoprotein(a)-based assay. Secondary end points included the percentage change in apolipoprotein B and high-sensitivity C-reactive protein.

Results

The median age of study participants was 66 years; 33% were female; and 27% identified as Asian, 4% as Black, and 66% as White. Muvalaplin resulted in placebo-adjusted reductions in lipoprotein(a) of 47.6% (95% CI, 35.1%-57.7%), 81.7% (95% CI, 78.1%-84.6%), and 85.8% (95% CI, 83.1%-88.0%) for the 10-mg/d, 60-mg/d, and 240-mg/d dosages, respectively, using an intact lipoprotein(a) assay and 40.4% (95% CI, 28.3%-50.5%), 70.0% (95% CI, 65.0%-74.2%), and 68.9% (95% CI, 63.8%-73.3%) using an apolipoprotein(a)-based assay. Dose-dependent reductions in apolipoprotein B were observed at 8.9% (95% CI, -2.2% to 18.8%), 13.1% (95% CI, 4.4%-20.9%), and 16.1% (95% CI, 7.8%-23.7%) at 10 mg/d, 60 mg/d, and 240 mg/d, respectively. No change in high-sensitivity C-reactive protein was observed. No safety or tolerability concerns were observed at any dosage.

Conclusions and Relevance

Muvalaplin reduced lipoprotein(a) measured using intact lipoprotein(a) and apolipoprotein(a)-based assays and was well tolerated. The effect of muvalaplin on cardiovascular events requires further investigation.

Trial Registration

ClinicalTrials.gov Identifier: NCT05563246.

Clinical Impact of Lipoprotein (a) and Cumulative Low-Density Lipoprotein Cholesterol Exposure on Coronary Artery Disease in Patients with Heterozygous Familial Hypercholesterolemia

AIMS

Elevated lipoprotein (a) (Lp[a]), predominantly determined by genetic variability, causes atherosclerotic cardiovascular disease (ASCVD), particularly in patients with familial hypercholesterolemia (FH). We aimed to elucidate the clinical impact of Lp(a) and cumulative exposure to low-density lipoprotein cholesterol (LDL-C) on CAD in patients with FH.

METHODS

One hundred forty-seven patients clinically diagnosed with heterozygous familial hypercholesterolemia (HeFH) were retrospectively investigated. Patients were divided into 2 groups according to the presence of CAD. Their clinical characteristics and lipid profiles were evaluated.

RESULTS

There were no significant differences in untreated LDL-C levels between the 2 groups (p=0.4), whereas the cumulative exposure to LDL-C and Lp(a) concentration were significantly higher in patients with CAD (11956 vs. 8824 mg-year/dL, p＜0.01; 40 vs. 14 mg/dL, p＜0.001, respectively). A receiver operating characteristic (ROC) curve analysis demonstrated that the cutoff values of Lp(a) and cumulative LDL-C exposure to predict CAD in patients with FH were 28 mg/dL (AUC 0.71) and 10600 mg-year/dL (AUC 0.77), respectively. A multivariate analysis revealed that cumulative LDL-C exposure ≥ 10600 mg-year/dL (p＜0.0001) and Lp(a) level ≥ 28 mg/dL (p＜0.001) were independent predictors of CAD. Notably, the risk of CAD remarkably increased to 85.7% with smoking, Lp(a) ≥ 28 mg/dL, and cumulative LDL-C exposure ≥ 10600 mg-year/dL (odds ratio: 46.5, 95%CI: 5.3-411.4, p＜0.001).

CONCLUSIONS

This study demonstrated an additive effect of Lp(a) and cumulative LDL-C exposure on CAD in patients with HeFH. Interaction with traditional risk factors, particularly smoking and cumulative LDL-C exposure, enormously enhances the cardiovascular risk in this population.

Oral agents for lowering lipoprotein(a)

PURPOSE OF REVIEW

To review the development of oral agents to lower Lp(a) levels as an approach to reducing cardiovascular risk, with a focus on recent advances in the field.

RECENT FINDINGS

Extensive evidence implicates Lp(a) in the causal pathway of atherosclerotic cardiovascular disease and calcific aortic stenosis. There are currently no therapies approved for lowering of Lp(a). The majority of recent therapeutic advances have focused on development of injectable agents that target RNA and inhibit synthesis of apo(a). Muvalaplin is the first, orally administered, small molecule inhibitor of Lp(a), which acts by disrupting binding of apo(a) and apoB, in clinical development. Nonhuman primate and early human studies have demonstrated the ability of muvalaplin to produce dose-dependent lowering of Lp(a). Ongoing clinical trials will evaluate the impact of muvalaplin in high cardiovascular risk and will ultimately need to determine whether this strategy lowers the rate of cardiovascular events.

SUMMARY

Muvalaplin is the first oral agent, developed to lower Lp(a) levels. The ability of muvalaplin to reduce cardiovascular risk remains to be investigated, in order to determine whether it will be a useful agent for the prevention of cardiovascular disease.

Lipoprotein Apheresis: Utility, Outcomes, and Implementation in Clinical Practice: A Scientific Statement From the American Heart Association

Despite the availability of multiple classes of lipoprotein-lowering medications, some high-risk patients have persistent hypercholesterolemia and may require nonpharmacologic therapy. Lipoprotein apheresis (LA) is a valuable but underused adjunctive therapeutic option for low-density lipoprotein cholesterol and lipoprotein(a) lowering, particularly in children and adults with familial hypercholesterolemia. In addition to lipid lowering, LA reduces serum levels of proinflammatory and prothrombotic factors, reduces blood viscosity, increases microvascular myocardial perfusion, and may provide beneficial effects on endothelial function. Multiple observational studies demonstrate strong evidence for improved cardiovascular outcomes with LA; however, use in the United States is limited to a fraction of its Food and Drug Administration-approved indications. In addition, there are limited data regarding LA benefit for refractory focal segmental glomerulosclerosis. In this scientific statement, we review the history of LA, mechanisms of action, cardiovascular and renal outcomes data, indications, and options for treatment.

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.

Reducing Cardiovascular Disease-An Alternative Approach

PURPOSE

Statin drugs are effective at reducing cardiovascular events, but adherence to statin therapy remains a problem for patients and their physicians. We review a paper estimating the economic costs of poor adherence to statin drugs.

METHODS

The authors examined two large databases (Medicare and Market Scan databases) including 230,000 patients with hospitalization for myocardial infarction between 2018 and 2019 to determine how many patients were not adhering to guideline-recommended anti-hyperlipidemic medications. They have also calculated the potential consequences of patients who are not adhering to the recommended therapy.

RESULTS

The authors estimate that if all patients were receiving guideline-directed medical therapy, then a 22% relative risk reduction would occur in the 3-year period following discharge from the initial cardiovascular event. These findings are consistent with prior reports. This editorial discusses rationale and strategies clinicians can use to improve patients' compliance with recommendations for lipid-lowering therapy.

CONCLUSION

The authors conclude that better compliance with guideline-directed lipid therapy after a cardiovascular event would lead to a large reduction in second events. Increased efforts by clinicians to improve adherence to statin therapy are warranted.

Lp(a): A Rapidly Evolving Therapeutic Landscape

PURPOSE OF REVIEW

Elevated lipoprotein(a) (Lp[a]) is a genetically determined cardiovascular risk factor, causally linked to both atherosclerotic coronary artery disease and aortic stenosis. Elevated Lp(a) is widely prevalent, and several cardiovascular societies now recommend performing Lp(a) screening at least once in all adults. However, there are currently no approved drugs aimed specifically at lowering Lp(a). In this review, we describe several promising Lp(a)-lowering therapies in the drug development pipeline and outline what role these may have in future clinical practice.

RECENT FINDINGS

Pelacarsen and olpasiran are two novel RNA-based injectable therapies which are being studied in ongoing phase 3 clinical trials, with the earliest of these to be concluded in 2025. These drugs act by degrading transcribed LPA mRNA, which would normally yield the apolipoprotein(a) constituent of Lp(a). Other candidate drugs, such as Lepodisiran, Zerlasiran, and Muvalaplin, are also in early-stage development. While there are presently no Lp(a)-lowering drugs available for routine clinical use, several promising candidates are currently under investigation. If these prove to be effective in randomized clinical trials, they will expand the cardiovascular care armamentarium and will allow clinicians to treat a presently unmitigated cardiovascular risk factor.

High lipoprotein(a) is a risk factor for peripheral artery disease, abdominal aortic aneurysms, and major adverse limb events

PURPOSE OF REVIEW

To summarize evidence from recent studies of high lipoprotein(a) as a risk factor for peripheral artery disease (PAD), abdominal aortic aneurysms (AAA), and major adverse limb events (MALE). Additionally, provide clinicians with 10-year absolute risk charts enabling risk prediction of PAD and AAA by lipoprotein(a) levels and conventional risk factors.

RECENT FINDINGS

Numerous studies support high lipoprotein(a) as an independent risk factor for PAD, AAA, and MALE. The strongest evidence is from the Copenhagen General Population Study (CGPS) and the UK Biobank, two large general population-based cohorts. In the CGPS, a 50 mg/dl higher genetically determined lipoprotein(a) associated with hazard ratios of 1.39 (1.24-1.56) for PAD and 1.21 (1.01-1.44) for AAA. Corresponding hazard ratio in the UK Biobank were 1.38 (1.30-1.46) and 1.42 (1.28-1.59). In CGPS participants with levels at least 99th (≥143 mg/dl) vs, less than 50th percentile (≤9 mg/dl), hazard ratios were 2.99 (2.09-4.30) for PAD and 2.22 (1.21-4.07) for AAA, with a corresponding incidence rate ratio for MALE of 3.04 (1.55-5.98) in participants with PAD.

SUMMARY

Evidence from both observational and genetic studies support high lipoprotein(a) as a causal risk factor for PAD, AAA, and MALE, and highlight the potential of future lipoprotein(a)-lowering therapy to reduce the substantial morbidity and mortality associated with these diseases.

Lipoprotein(a) is a highly atherogenic lipoprotein: pathophysiological basis and clinical implications

PURPOSE OF REVIEW

Lipoprotein(a) has been identified as a causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and aortic valve stenosis. However, as reviewed here, there is ongoing debate as to the key pathogenic features of Lp(a) particles and the degree of Lp(a) atherogenicity relative to low-density lipoprotein (LDL).

RECENT FINDINGS

Genetic analyses have revealed that Lp(a) on a per-particle basis is markedly (about six-fold) more atherogenic than LDL. Oxidized phospholipids carried on Lp(a) have been found to have substantial pro-inflammatory properties triggering pathways that may contribute to atherogenesis. Whether the strength of association of Lp(a) with ASCVD risk is dependent on inflammatory status is a matter of current debate and is critical to implementing intervention strategies. Contradictory reports continue to appear, but most recent studies in large cohorts indicate that the relationship of Lp(a) to risk is independent of C-reactive protein level.

SUMMARY

Lp(a) is a highly atherogenic lipoprotein and a viable target for intervention in a significant proportion of the general population. Better understanding the basis of its enhanced atherogenicity is important for risk assessment and interpreting intervention trials.

Role of Lipoprotein(a) Reduction in Cardiovascular Disease

Recent studies have shown that lipoprotein(a) (Lp(a)) is an important risk factor for a plethora of different cardiovascular diseases. It has been proven that Lp(a) levels are genetically determined and correlate with risk of cardiovascular disease, independent of lifestyle factors. As of yet, treatment options to reduce Lp(a) levels are limited, but new research into Lp(a) reduction yields promising results. This review delves into Lp(a)'s biochemistry and mechanism of effect, the association between Lp(a) and cardiovascular diseases, and possible therapies to minimise cardiovascular disease.

Lipoprotein (a) as a Cardiovascular Risk Factor in Controversial Clinical Scenarios: A Narrative Review

Lipoprotein (a) is a complex lipid molecule that has sparked immense interest in recent years, after studies demonstrated its significant association with several cardiovascular conditions. Lp(a) promotes cardiovascular disease through its combined proatherogenic, pro-inflammatory, and prothrombotic effects. While the measurement of Lp(a) has become widely available, effective methods to reduce its concentration are currently limited. However, emerging data from ongoing clinical trials involving antisense oligonucleotides have indicated promising outcomes in effectively reducing Lp(a) concentrations. This may serve as a potential therapeutic target in the management and prevention of myocardial infarction, calcific aortic stenosis, and cerebrovascular accidents. In contrast, the role of Lp(a) in atrial fibrillation, in-stent restenosis, cardiac allograft vasculopathy, and bioprosthetic aortic valve degeneration remains unclear. This review article aims to thoroughly review the existing literature and provide an updated overview of the evidence surrounding the association of Lp(a) and these cardiovascular diseases. We seek to highlight controversies in the existing literature and offer directions for future investigations to better understand Lp(a)'s precise role in these conditions, while providing a summary of its unique molecular characteristics.

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.

Lipoprotein(a) and risk-weighted apolipoprotein B: a novel metric for atherogenic risk

BACKGROUND

Retention of apolipoprotein B (apoB)-containing lipoproteins within the arterial wall plays a major causal role in atherosclerotic cardiovascular disease (ASCVD). There is a single apoB molecule in all apoB-containing lipoproteins. Therefore, quantitation of apoB directly estimates the number of atherogenic particles in plasma. ApoB is the preferred measurement to refine the estimate of ASCVD risk. Low-density lipoprotein (LDL) particles are by far the most abundant apoB-containing particles. In patients with elevated lipoprotein(a) (Lp(a)), apoB may considerably underestimate risk because Mendelian randomization studies have shown that the atherogenicity of Lp(a) is approximately 7-fold greater than that of LDL on a per apoB particle basis. In subjects with increased Lp(a), the association between LDL-cholesterol and incident CHD (coronary heart disease) is increased, but the association between apoB and incident CHD is diminished or even lost. Thus, there is a need to understand the mechanisms of Lp(a), LDL-cholesterol and apoB-related CHD risk and to provide clinicians with a simple practical tool to address these complex and variable relationships. How can we understand a patient's overall lipid-driven atherogenic risk? What proportion of this risk does apoB capture? What proportion of this risk do Lp(a) particles carry? To answer these questions, we created a novel metric of atherogenic risk: risk-weighted apolipoprotein B.

METHODS

In nmol/L: Risk-weighted apoB = apoB - Lp(a) + Lp(a) x 7 = apoB + Lp(a) x 6. Proportion of risk captured by apoB = apoB divided by risk-weighted apoB. Proportion of risk carried by Lp(a) = Lp(a) × 7 divided by risk-weighted apoB.

RESULTS

Risk-weighted apoB agrees with risk estimation from large epidemiological studies and from several Mendelian randomization studies.

CONCLUSIONS

ApoB considerably underestimates risk in individuals with high Lp(a) levels. The association between apoB and incident CHD is diminished or even lost. These phenomena can be overcome and explained by risk-weighted apoB.

Lipoprotein (a) is associated with increased risk of Abdominal Aortic Aneurysm

Introduction

Lipoprotein(a) (Lp(a)) is a circulating apolipoprotein B (ApoB) containing particle that has been observationally linked to atherosclerotic cardiovascular disease and is the target of emerging therapeutics. Recent work has highlighted the role of circulating lipoproteins in abdominal aortic aneurysm (AAA). We sought to triangulate human observational and genetic evidence to evaluate the role of Lp(a) in AAA.

Methods

We tested the association between circulating levels of Lp(a) and clinically diagnosed abdominal aortic aneurysms while controlling for traditional AAA risk factors and levels of ApoB using logistic regression among 795 individuals with and 374,772 individuals without AAA in the UK Biobank (UKB). Multivariable Mendelian randomization (MVMR) was used to test for putatively causal associations between Lp(a) and AAA controlling for ApoB. Genetic instruments for Lp(a) and ApoB were created from genome-wide association studies (GWAS) of Lp(a) and ApoB comprising 335,796 and 418,505 UKB participants, respectively. The instruments were tested for association with AAA using data from a GWAS of 39,221 individuals with and 1,086,107 without AAA.

Results

Elevated Lp(a) levels were observationally associated with an increased risk of AAA (OR 1.04 per 10 nmol/L Lp(a); 95%CI 1.02-1.05; P<0.01). Clinically elevated Lp(a) levels (>150nmol/L) were likewise associated with an increased risk of AAA (OR 1.47; 95% CI 1.15-1.88; P < 0.01) when compared to individuals with Lp(a) levels <150nmol/L. MVMR confirmed a significant, ApoB-independent association between increased Lp(a) and increased risk of AAA (OR 1.13 per SD increase in Lp(a); 95%CI 1.02-1.24; P<0.02).

Conclusion

Both observational and genetic analyses support an association between increased Lp(a) and AAA risk that is independent of ApoB. These findings suggest that Lp(a) may be a therapeutic target for AAA and drive the inclusion of AAA as an outcome in clinical trials of Lp(a) antagonists.

Attitudes and barriers to lipoprotein(a) testing: A survey of providers at the University of Pennsylvania Health System

Guidelines recommend checking lipoprotein(a) [Lp(a)] levels in patients at high-risk for cardiovascular disease, with more recent recommendations advocating for universal screening in all adults. A brief electronic survey was distributed to select groups of University of Pennsylvania Health System (UPHS) providers, including Internal Medicine and Cardiology physicians and advance practice providers, to understand the current attitudes and barriers to testing for Lp(a). Of the 126 survey respondents, only 31% answered that they test for Lp(a) regularly in their practice. Presence of ASCVD and a family history of ASCVD were the most common reasons for testing. Most survey respondents (69%) replied that they do not currently check Lp(a) levels in patients. The most common reasons provided included lack of familiarity with Lp(a), insurance/ billing concerns, lack of clinical trial outcomes data, and lack of available pharmaceutical interventions. Results from ongoing clinical trials of novel Lp(a)-lowering therapies, if successful, may address provider hesitation toward Lp(a)-testing, but there remains a large gap to fill in awareness of Lp(a).

Recent Advances in Targeted Management of Inflammation In Atherosclerosis: A Narrative Review

Atherosclerotic cardiovascular disease (ASCVD) remains a leading cause of morbidity and mortality despite effective low-density lipoprotein cholesterol-targeted therapies. This review explores the crucial role of inflammation in the residual risk of ASCVD, emphasizing its impact on atherosclerosis progression and plaque stability. Evidence suggests that high-sensitivity C-reactive protein (hsCRP), and potentially other inflammatory biomarkers, can be used to identify the inflammatory residual ASCVD risk phenotype and may serve as future targets for the development of more efficacious therapeutic approaches. We review the biological basis for the association of inflammation with ASCVD, propose new therapeutic strategies for the use of inflammation-targeted treatments, and discuss current challenges in the implementation of this new treatment paradigm for ASCVD.

Lipoprotein (a) and lipid-lowering treatment from the perspective of a cardiac surgeon. An impact on the prognosis in patients with aortic valve replacement and after heart transplantation

Lipoprotein(a) is a recognized risk factor for ASCVD. There is still no targeted therapy for Lp(a), however, drugs such as pelacarsen, olpasiran, zerlasiran, lepodisiran and muvalaplin are in clinical trials and have been shown to be effective in significantly reducing Lp(a) levels. Moreover, elevated Lp(a) levels significantly affect the prognosis of patients after aortic valve replacement (AVR) and heart transplantation (HTx). Therefore, the assessment of Lp(a) concentration in these patients will allow for a more accurate stratification of their cardiovascular risk, and the possibility of lowering Lp(a) will allow for the optimization of this risk. In this article, we summarized the most important information regarding the role of Lp(a) and lipid-lowering treatment in patients after AVR and HTx.

Atherogenic lipid profile in patients with statin treatment after acute coronary syndrome: a real-world analysis from Chinese cardiovascular association database

BACKGROUND

Adverse atherogenic lipid profile is associated with an increased risk of major adverse cardiac events in patients after acute coronary syndrome (ACS). Knowledge regarding the impact of statins on lipid profile remains limited.

METHODS

We retrospectively analysed multicenter, real-world data from the Chinese Cardiovascular Association Database-iHeart Project. Patients with a primary diagnosis of ACS from 2014 to 2021 during index hospitalisation and having at least one lipid panel record after discharge within 12 months were enrolled. We analysed target achievement of atherogenic lipid profile, including apolipoprotein B (< 80 mg/dL), low-density lipoprotein cholesterol (LDL-C) (< 1.8 mmol/L), lipoprotein(a) [Lp(a)] (< 30 mg/dL), triglycerides (< 1.7 mmol/L), remnant cholesterol (RC) (< 0.78 mmol/L), non-high-density lipoprotein cholesterol (< 2.6 mmol/L) at baseline and follow-up. Multivariate Cox regression models were employed to investigate the association between patient characteristics and target achievement.

RESULTS

Among 4861 patients, the mean age was 64.9 years. Only 7.8% of patients had all atherogenic lipids within the target range at follow-up. The proportion of target achievement was for LDL-C 42.7%, Lp(a) 73.3%, and RC 78.5%. Patients with female sex, younger age, myocardial infarction, hypertension, and hypercholesteremia were less likely to control LDL-C, Lp(a), and RC. An increase in the burden of comorbidities was negatively associated with LDL-C and Lp(a) achievements but not with RC.

CONCLUSIONS

A substantial gap exists between lipid control and the targets recommended by contemporary guidelines. Novel therapeutics targeting the whole atherogenic lipid profile will be warranted to improve cardiovascular outcomes.