Lipoprotein(a): Emerging insights and therapeutics

The strong association between lipoprotein (a) [Lp(a)] and atherosclerotic cardiovascular disease has led to considerations of Lp(a) being a potential target for mitigating residual cardiovascular risk. While approximately 20 % of the population has an Lp(a) level greater than 50 mg/dL, there are no currently available pharmacological lipid-lowering therapies that have demonstrated substantial reduction in Lp(a). Novel therapies to lower Lp(a) include antisense oligonucleotides and small-interfering ribonucleic acid molecules and have shown promising results in phase 2 trials. Phase 3 trials are currently underway and will test the causal relationship between Lp(a) and ASCVD and whether lowering Lp(a) reduces cardiovascular outcomes. In this review, we summarize emerging insights related to Lp(a)'s role as a risk-enhancing factor for ASCVD, association with calcific aortic stenosis, effects of existing therapies on Lp(a) levels, and variations amongst patient populations. The evolving therapeutic landscape of emerging therapeutics is further discussed.

Association between lipoprotein(a) and cardiovascular disease in patients undergoing coronary angiography

OBJECTIVE

Many previous studies reported the relationship between lipoprotein(a) and cardiovascular disease, but the conclusions were controversial. The aim of our study was to retrospectively investigate the association between lipoprotein(a) and cardiovascular disease in patients undergoing coronary angiography.

METHODS

We collected and compared clinical information of patients hospitalized for coronary angiography. Multivariable hierarchical logistic regression was used to evaluate the association between lipoprotein(a) and cardiovascular disease in patients undergoing coronary angiography.

RESULTS

There were no significant differences in gender, hypertension, APOA1, smoking, hyperuricemia, obesity, acute myocardial infarction (AMI), cardiac insufficiency, family history of diabetes, or family history of hyperlipidemia among the four groups of lipoprotein(a). Elevated lipoprotein(a) does not increase the risk of hypertriglyceridemia, while elevated lipoprotein(a) increases the risk of high total cholesterol and high low-density lipoprotein cholesterol (LDL-c). Elevated lipoprotein(a) increases the risk of diabetes and premature coronary artery disease (CAD). Elevated lipoprotein(a) increases the incidence of CAD, multivessel lesions, and percutaneous coronary intervention (PCI). Multivariate logistic regression analysis further showed that elevated lipoprotein(a) increases the incidence of high total cholesterol, high LDL‑c, diabetes, CAD, premature CAD, multivessel lesions, and PCI.

CONCLUSION

The findings indicated that elevated lipoprotein(a) had no obvious relationship with hypertension and obesity. Elevated lipoprotein(a) increases the risk of high total cholesterol, high LDL‑c, and premature CAD, and increases the occurrence and severity of coronary heart disease.

Prevalence of elevated lipoprotein(a) in cardiac rehabilitation patients - results from a large-scale multicentre registry in Germany

BACKGROUND

Lipoprotein(a) (Lp(a)) is an independent risk factor for myocardial infarction and aortic valve stenosis. European guidelines recommend assessing it at least once in a lifetime, particularly in premature atherosclerotic heart disease.

METHODS

A non-interventional registry was conducted at MEDIAN rehabilitation facilities in Germany to assess the frequency of Lp(a) testing in referring acute care hospitals and the prevalence of elevated Lp(a) levels in aortic valve stenosis or premature myocardial infarction. All consecutive patients referred after coronary intervention or aortic valve surgery were included in four cohorts: aortic valve intervention (cohort 1), current/previous myocardial infarction at < 60 years of age (cohorts 2a/2b), and myocardial infarction at ≥ 60 years of age (control).

RESULTS

The analysis included 3393 patient records (cohort 1, n = 1063; cohort 2a, n = 1351; cohort 2b, n = 381; control, n = 598). Lp(a) had been determined at the referring hospital in 0.19% (cohort 1), 4.96% (cohort 2a), 2.36% (cohort 2b), and 2.01% (control) of patients. Lp(a) levels were > 50 mg/dL or > 125 nmol/L in 28.79% (cohort 1), 29.90% (cohort 2a), and 36.48% (cohort 2b; p < 0.001) compared to 24.25% (control). Family history of premature cardiovascular disease was reported in 13.45% (cohort 1), 38.56% (cohort 2a), and 32.81% (cohort 2b) compared to 17.89% (control; p < 0.05 for each comparison).

CONCLUSIONS

Lp(a) had been rarely assessed in acute management of aortic valve stenosis or premature myocardial infarction despite expanding scientific evidence and guideline recommendation. Given the above-average incidence of elevated Lp(a) levels, awareness for Lp(a) has to increase substantially to better identify and manage high-risk patients.

Joint Association of Lipoprotein(a) and a Family History of Coronary Artery Disease with the Cardiovascular Outcomes in Patients with Chronic Coronary Syndrome

AIM

No data are currently available regarding the association between Lp(a) and the cardiovascular outcomes in patients with coronary artery disease (CAD) according to their family history (FHx) of CAD. This study aimed to evaluate the significance of Lp(a) in predicting major adverse cardiovascular events (MACEs) in patients with chronic coronary syndrome (CCS) with or without FHx.

METHODS

A total of 6056 patients with CCS were enrolled. Information on FHx was collected, and the plasma Lp(a) levels were measured. All patients were followed up regularly. The independent and joint associations of Lp(a) and FHx with the risk of MACEs, including cardiovascular death, nonfatal myocardial infarction, and stroke, were analyzed.

RESULTS

With over an average of 50.35±18.58 months follow-up, 378 MACEs were recorded. A Cox regression analysis showed an elevated Lp(a) level to be an independent predictor for MACEs in patients with [hazard ratio (HR): 2.77, 95% confidence interval (CI): 1.38-5.54] or without FHx (HR: 1.35, 95% CI: 1.02-1.77). In comparison to subjects with non-elevated Lp(a) and negative FHx, patients with elevated Lp(a) alone were at a nominally higher risk of MACEs (HR: 1.26, 95% CI: 0.96-1.67), while those with both had the highest risk (HR: 1.93, 95% CI: 1.14-3.28). Moreover, adding Lp(a) to the original model increased the C-statistic by 0.048 in subjects with FHx (p=0.004) and by 0.004 in those without FHx (p=0.391).

CONCLUSIONS

The present study is the first to suggest that Lp(a) could be used to predict MACEs in CCS patients with or without FHx; however, its prognostic significance was more noteworthy in patients with FHx.

Association between lipoprotein(a), LPA genetic risk score, aortic valve disease, and subsequent major adverse cardiovascular events

AIMS

Cohort studies have demonstrated associations between calcific aortic valve disease (CAVD) and Lp(a). As Lp(a) is almost entirely genetically determined, in this study, we aim to determine whether Lp(a), when predicted from genetic data, is associated with CAVD and major adverse cardiovascular events (MACEs).

METHODS AND RESULTS

Patients undergoing coronary angiography between January 2012 and May 2013 were invited to participate in the study. Of 752 analysable participants, 446 had their Lp(a) measured and 703 had a calculable LPA genetic risk score (GRS). The primary outcomes were the presence of CAVD at baseline and MACE over a 7-year follow-up. The GRS explained 45% of variation in Lp(a). After adjustment for cardiac risk factors and coronary artery disease (CAD), the odds of CAVD increased with increasing Lp(a) [odds ratio (OR) 1.039 per 10-unit increase, 95% confidence interval (CI) 1.022-1.057, P < 0.001] and GRS (OR 1.054 per 10-unit increase, 95% CI 1.024-1.086; P < 0.001). Lipoprotein(a) and the GRS as continuous variables were not associated with subsequent MACEs. A dichotomized GRS (>54) was associated with MACE, but this relationship became non-significant when CAD classification was added into the model (OR 1.333, 95% CI 0.927-1.912; P = 0.12).

CONCLUSION

An LPA GRS can explain 45% of variation in Lp(a) levels, and both Lp(a) and the GRS are associated with CAVD. An elevated GRS is associated with future cardiac events in a secondary risk setting, but, if the CAD status is known, it does not provide additional prognostic information.

Apolipoprotein(a) production and clearance are associated with plasma IL-6 and IL-18 levels, dependent on ethnicity

BACKGROUND AND AIMS

High plasma lipoprotein (a) [Lp(a)] levels are associated with increased atherosclerotic cardiovascular disease (ASCVD), in part attributed to elevated inflammation. High plasma Lp(a) levels inversely correlate with apolipoprotein (a) [(APO(a)] isoform size. APO(a) isoform size is negatively associated with APO(a) production rate (PR) and positively associated with APO(a) fractional catabolic rate (FCR). We asked whether APO(a) PR and FCR (kinetics) are associated with plasma levels of interleukin (IL)-6 and IL-18, pro-inflammatory interleukins that promote ASCVD.

METHODS

We used samples from existing data of APO(a) kinetic studies from an ethnically diverse cohort (n = 25: 10 Black, 9 Hispanic, and 6 White subjects) and assessed IL-6 and IL-18 plasma levels. We performed multivariate linear regression analyses to examine the relationships between predictors APO(a) PR or APO(a) FCR, and outcome variables IL-6 or IL-18. In these analyses, we adjusted for parameters known to affect Lp(a) levels and APO(a) PR and FCR, including race/ethnicity and APO(a) isoform size.

RESULTS

APO(a) PR and FCR were positively associated with plasma IL-6, independent of isoform size, and dependent on race/ethnicity. APO(a) PR was positively associated with plasma IL-18, independent of isoform size and race/ethnicity. APO(a) FCR was not associated with plasma IL-18.

CONCLUSIONS

Our studies demonstrate a relationship between APO(a) PR and FCR and plasma IL-6 or IL-18, interleukins that promote ASCVD. These studies provide new insights into Lp(a) pro-inflammatory properties and are especially relevant in view of therapies targeting APO(a) to decrease cardiovascular risk.

Novel Therapies for Lipoprotein(a): Update in Cardiovascular Risk Estimation and Treatment

PURPOSE OF REVIEW

Lipoprotein(a) is an important causal risk factor for cardiovascular disease but currently no available medication effectively reduces lipoprotein(a). This review discusses recent findings regarding lipoprotein(a) as a causal risk factor and therapeutic target in cardiovascular disease, it reviews current clinical recommendations, and summarizes new lipoprotein(a) lowering drugs.

RECENT FINDINGS

Epidemiological and genetic studies have established lipoprotein(a) as a causal risk factor for cardiovascular disease and mortality. Guidelines worldwide now recommend lipoprotein(a) to be measured once in a lifetime, to offer patients with high lipoprotein(a) lifestyle advise and initiate other cardiovascular medications. Clinical trials including antisense oligonucleotides, small interfering RNAs, and an oral lipoprotein(a) inhibitor have shown great effect on lowering lipoprotein(a) with reductions up to 106%, without any major adverse effects. Recent clinical phase 1 and 2 trials show encouraging results and ongoing phase 3 trials will hopefully result in the introduction of specific lipoprotein(a) lowering drugs to lower the risk of cardiovascular disease.

Lipoprotein(a) is associated with recurrent cardiovascular events in patients with coronary artery disease and prediabetes or diabetes

PURPOSE

Elevated lipoprotein(a) [Lp(a)] and diabetes mellitus (DM) are both associated with adverse events in high-risk patients with established coronary artery disease (CAD). Currently, the association between Lp(a) levels and recurrent cardiovascular (CV) events (CVEs) remained undetermined in patients with different glucose status. Therefore, this study aimed to investigate the prognostic significance of Lp(a) levels for recurrent CVEs in high-risk CAD patients who suffered from first CVEs according to different glycemic metabolism.

METHODS

We recruited 5257 consecutive patients with prior CVEs and followed up for recurrent CVEs, including CV death, non-fatal myocardial infarction (MI), and non-fatal stroke. Patients were assigned to low, medium, and high groups according to Lp(a) levels and further stratified by glucose status.

RESULTS

During a median 37-month follow-up, 225 (4.28%) recurrent CVEs occurred. High Lp(a) was independently associated with recurrent CVEs [adjusted Hazard Ratio (HR), 1.57; 95% confidence interval (CI) 1.12-2.19; P = 0.008]. When participants were classified according to Lp(a) levels and glycemic status, high Lp(a) levels were associated with an increased risk of recurrent CVEs in pre-DM (adjusted HR, 2.96; 95% CI 1.24-7.05; P = 0.014). Meanwhile, medium and high Lp(a) levels were both associated with an increased risk for recurrent CVEs in DM (adjusted HR, 3.09; 95% CI 1.30-7.34; P = 0.010 and adjusted HR, 3.13, 95% CI 1.30-7.53; P = 0.011, respectively).

CONCLUSIONS

This study demonstrated that elevated Lp(a) levels were associated with an increased recurrent CVE risk in patients with CAD, particularly among those with pre-DM and DM, indicating that Lp(a) may provide incremental value in risk stratification in this population.

Lp(a) - an overlooked risk factor

Lipoprotein(a) (Lp(a)) is an increasingly discussed and studied risk factor for atherosclerotic cardiovascular disease and aortic valve stenosis. Many genetic and epidemiological studies support the important causal role that Lp(a) plays in the incidence of cardiovascular disease. Although dependent upon the threshold and unit of measurement of Lp(a), most estimates suggest between 20 and 30% of the world's population have elevated serum levels of Lp(a). Lp(a) levels are predominantly mediated by genetics and are not significantly modified by lifestyle interventions. Efforts are ongoing to develop effective pharmacotherapies to lower Lp(a) and to determine if lowering Lp(a) with these medications ultimately decreases the incidence of adverse cardiovascular events. In this review, the genetics and pathophysiological properties of Lp(a) will be discussed as well as the epidemiological data demonstrating its impact on the incidence of cardiovascular disease. Recommendations for screening and how to currently approach patients with elevated Lp(a) are also noted. Finally, the spectrum of pharmacotherapies under development for Lp(a) lowering is detailed.

A focused update to the 2019 NLA scientific statement on use of lipoprotein(a) in clinical practice

Since the 2019 National Lipid Association (NLA) Scientific Statement on Use of Lipoprotein(a) in Clinical Practice was issued, accumulating epidemiological data have clarified the relationship between lipoprotein(a) [Lp(a)] level and cardiovascular disease risk and risk reduction. Therefore, the NLA developed this focused update to guide clinicians in applying this emerging evidence in clinical practice. We now have sufficient evidence to support the recommendation to measure Lp(a) levels at least once in every adult for risk stratification. Individuals with Lp(a) levels <75 nmol/L (30 mg/dL) are considered low risk, individuals with Lp(a) levels ≥125 nmol/L (50 mg/dL) are considered high risk, and individuals with Lp(a) levels between 75 and 125 nmol/L (30-50 mg/dL) are at intermediate risk. Cascade screening of first-degree relatives of patients with elevated Lp(a) can identify additional individuals at risk who require intervention. Patients with elevated Lp(a) should receive early, more-intensive risk factor management, including lifestyle modification and lipid-lowering drug therapy in high-risk individuals, primarily to reduce low-density lipoprotein cholesterol (LDL-C) levels. The U.S. Food and Drug Administration approved an indication for lipoprotein apheresis (which reduces both Lp(a) and LDL-C) in high-risk patients with familial hypercholesterolemia and documented coronary or peripheral artery disease whose Lp(a) level remains ≥60 mg/dL [∼150 nmol/L)] and LDL-C ≥ 100 mg/dL on maximally tolerated lipid-lowering therapy. Although Lp(a) is an established independent causal risk factor for cardiovascular disease, and despite the high prevalence of Lp(a) elevation (∼1 of 5 individuals), measurement rates are low, warranting improved screening strategies for cardiovascular disease prevention.

Lipoprotein a - Lp(a)

Lp(a) is a genetically determined, heritable, independent and causal risk factor for ASCVD. About 1 in 5 people worldwide have elevated Lp(a) (>50 mg/dL or >125 nmol/L) whereas in Indians it is 25 %. Epidemiological, genome-wide association and mendelian randomization studies have demonstrated an association between elevated Lp(a) levels and increased incidence of myocardial infarction, aortic valve stenosis, ischemic stroke, heart failure, CV and all-cause mortality. The increased Lp(a)-mediated CV risk is mediated by pro-inflammatory, pro-thrombotic and pro-atherogenic processes, leading to progression of atherosclerosis and increased risk of thrombosis. Lp(a) level reaches peak by 5 years of age and remains stable over time. Levels are not much influenced by dietary and environmental factors but it can vary in certain clinical situations like thyroid diseases, chronic kidney disease, inflammation and sepsis. It should be measured at least once in life time. Cascade testing for high Lp(a) is recommended in the settings of FH, family history of (very) high Lp(a), and personal or family history of ASCVD. In the absence of specific Lp(a)-lowering therapies, comprehensive risk factor management is recommended as per guidelines for individuals with elevated Lp(a). PCSK9 inhibitors and Inclisiran reduce Lp(a) by 25%. Pelacarsen is an antisense oligonucleotide and is found to reduce Lp(a) by 80%. In a recent Indian study of 1,021 CAD patients, presence of elevated Lp(a) (>50 mg/dL) correlated with severe angiographic disease. 37% of ACS patients exhibited elevated Lp(a) and it was higher in young CAD patients with FH (43%).

Lipoprotein(a): from Causality to Treatment

PURPOSE OF REVIEW

This paper reviews the evidence why lipoprotein(a) (Lp(a)) is a causal risk factor for cardiovascular disease and how high Lp(a) concentrations should be managed now and with an outlook to the future.

REVIEW FINDINGS

No optimal and widely available animal models exist to study the causality of the association between Lp(a) and cardiovascular disease. This has been a major handicap for the entire field. However, genetic studies turned the page. Already in the early 1990s, the principle of Mendelian randomization studies was applied for the first time ever (even if they were not named so at that time). Genetic variants of the LPA gene such as the apolipoprotein(a) isoform size, the number and sum of kringle IV repeats and later single nucleotide polymorphisms are strongly associated with life-long exposure to high Lp(a) concentrations as well as cardiovascular outcomes. This evidence provided a basis for the development of specific Lp(a)-lowering drugs that are currently in clinical testing phase. Lp(a) is one of the most important genetically determined risk factors for cardiovascular disease. With the specific Lp(a)-lowering therapies, we might get tools to fight this common risk factor in case the outcome trials will be positive.

Influence of triglyceride concentration in lipoprotein (a) as a function of dyslipidemia

BACKGROUND

Recently, an inverse relationship between the blood concentration of lipoprotein(a) (Lp(a)) and triglycerides (TG) has been demonstrated. The larger the VLDL particle size, the greater the presence of VLDL rich in apoliprotein E and in subjects with the apoE2/E2 genotype, the lower Lp(a) concentration. The mechanism of this inverse association is unknown. The objective of this analysis was to evaluate the Lp(a)-TG association in patients treated at the lipid units included in the registry of the Spanish Society of Atherosclerosis (SEA) by comparing the different dyslipidemias.

PATIENTS AND METHODS

Five thousand two hundred and seventy-five subjects ≥18 years of age registered in the registry before March 31, 2023, with Lp(a) concentration data and complete lipid profile information without treatment were included.

RESULTS

The mean age was 53.0 ± 14.0 years, with 48% women. The 9.5% of subjects (n = 502) had diabetes and the 22.4% (n = 1184) were obese. The median TG level was 130 mg/dL (IQR 88.0-210) and Lp(a) 55.0 nmol/L (IQR 17.9-156). Lp(a) concentration showed a negative association with TG concentration when TG values exceeded 300 mg/dL. Subjects with TG > 1000 mg/dL showed the lowest level of Lp(a), 17.9 nmol/L, and subjects with TG < 300 mg/dL had a mean Lp(a) concentration of 60.1 nmol/L. In subjects without diabetes or obesity, the inverse association of Lp(a)-TG was especially important (p < 0.001). The median Lp(a) was 58.3 nmol/L in those with TG < 300 mg/dL and 22.0 nmol/L if TG > 1000 mg/dL. No association was found between TG and Lp(a) in subjects with diabetes and obesity, nor in subjects with familial hypercholesterolemia. In subjects with multifactorial combined hyperlipemia with TG < 300 mg/dL, Lp(a) was 64.6 nmol/L; in the range of 300-399 mg/dL of TG, Lp(a) decreased to 38. 8 nmol/L, and up to 22.3 nmol/L when TG > 1000 mg/dL.

CONCLUSIONS

Our results show an inverse Lp(a)-TG relationship in TG concentrations > 300 mg/dL in subjects without diabetes, obesity and without familial hypercholesterolemia. Our results suggest that, in those hypertriglyceridemias due to hepatic overproduction of VLDL, the formation of Lp(a) is reduced, unlike those in which the peripheral catabolism of TG-rich lipoproteins is reduced.

Novel Pharmacotherapies for Hyperlipidemia

The link between elevated LDL-C, low HDL-C, elevated triglycerides, and an increased risk for cardiovascular disease has solidified over the past decades. Concomitantly, the number of agents to treat dyslipidemia proliferated in clinical trials, proving or refuting their clinical efficacy. Many of these agents' role in reducing cardiovascular disease morbidity and mortality is now clear. Recently, there has been an explosion in emerging therapeutics for the primary and secondary prevention of cardiovascular disease through the control of dyslipidemia. This article reviews standard, new, and emerging treatments for hyperlipidemia.

Targeting Lipoprotein(a): Can RNA Therapeutics Provide the Next Step in the Prevention of Cardiovascular Disease?

Numerous genetic and epidemiologic studies have demonstrated an association between elevated levels of lipoprotein(a) (Lp[a]) and cardiovascular disease. As a result, lowering Lp(a) levels is widely recognized as a promising strategy for reducing the risk of new-onset coronary heart disease, stroke, and heart failure. Lp(a) consists of a low-density lipoprotein-like particle with covalently linked apolipoprotein A (apo[a]) and apolipoprotein B-100, which explains its pro-thrombotic, pro-inflammatory, and pro-atherogenic properties. Lp(a) serum concentrations are genetically determined by the apo(a) isoform, with shorter isoforms having a higher rate of particle synthesis. To date, there are no approved pharmacological therapies that effectively reduce Lp(a) levels. Promising treatment approaches targeting apo(a) expression include RNA-based drugs such as pelacarsen, olpasiran, SLN360, and lepodisiran, which are currently in clinical trials. In this comprehensive review, we provide a detailed overview of RNA-based therapeutic approaches and discuss the recent advances and challenges of RNA therapeutics specifically designed to reduce Lp(a) levels and thus the risk of cardiovascular disease.

Association of Lipoprotein (a) with peri-coronary inflammation in persons with and without HIV infection

BACKGROUND

Persons with HIV (PWH) have an increased risk of developing cardiovascular disease (CVD) compared to persons without HIV (PWoH). Lipoprotein a (Lp(a)) is a known atherosclerotic risk factor in PWoH, but there are no studies investigating Lp(a) and peri-coronary inflammation.

OBJECTIVE

To investigate whether Lp(a) is associated with peri-coronary inflammation as assessed by the fat attenuation index (FAI) and activated monocytes and T lymphocytes in PWH and PWoH.

METHODS

We measured plasma levels of Lp(a) at study entry in 58 PWH and 21 PWoH without CVD and who had FAI measurements. Associations of Lp(a) with FAI values of the right coronary artery (RCA) and left anterior descending artery (LAD) were evaluated using multivariable regression models adjusted for potential confounders. Correlations between Lp(a) levels and systemic inflammatory markers and immune cell subsets were examined.

RESULTS

Lp(a) was associated with greater peri-coronary inflammation among PWH compared to PWoH (β=1.73, P=0.019) in the RCA, in adjusted models. Significant correlations were observed with certain inflammatory markers (TNFR-I, b=0.295, P<0.001; TNFR-II, b=0.270, P=0.002; hs-CRP, b=0.195, P=0.028). Significant correlations were found between Lp(a) levels and several markers of monocyte activation: CD16 -CD163+ (b= -0.199, P=0.024), and CD16 -DR+ MFI (b= -0.179, P=0.042) and T cell subset CD38+CD4+ TEMRA (b= 0.177, P= 0.044).

CONCLUSIONS

Lp(a) was associated with greater peri-coronary inflammation in the RCA in PWH compared to PWoH, as well as with select systemic inflammatory markers and specific subsets of immune cells in peripheral circulation.

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.

Aspirin and Cardiovascular Risk in Individuals With Elevated Lipoprotein(a): The Multi-Ethnic Study of Atherosclerosis

BACKGROUND

Effective therapies for reducing cardiovascular disease (CVD) risk in people with elevated lipoprotein(a) are lacking, especially for primary prevention. Because of the potential association of lipoprotein(a) with thrombosis, we evaluated the relationship between aspirin use and CVD events in people with elevated lipoprotein(a).

METHODS AND RESULTS

We used data from the MESA (Multi-Ethnic Study of Atherosclerosis), a prospective cohort study of individuals free of baseline cardiovascular disease. Due to potential confounding by indication, we matched aspirin users to nonusers using a propensity score based on CVD risk factors. We then evaluated the association between aspirin use and coronary heart disease (CHD) events (CHD death, nonfatal myocardial infarction) stratified by baseline lipoprotein(a) level (threshold of 50 mg/dL) using Cox proportional hazards models with adjustment for CVD risk factors. After propensity matching, the study cohort included 2183 participants, including 1234 (57%) with baseline aspirin use and 423 (19%) with lipoprotein(a) >50 mg/dL. Participants with lipoprotein(a) >50 mg/dL had a higher burden of CVD risk factors, more frequent aspirin use (61.7% versus 55.3%, P=0.02), and higher rate of incident CHD events (13.7% versus 8.9%, P<0.01). Aspirin was associated with a significant reduction in CHD events among those with elevated lipoprotein(a) (hazard ratio, 0.54 [95% CI, 0.32-0.94]; P=0.03). Those with lipoprotein(a) >50 mg/dL and aspirin use had similar CHD risk as those with lipoprotein(a) ≤50 mg/dL regardless of aspirin use.

CONCLUSIONS

Aspirin use was associated with a significantly lower risk for CHD events in participants with lipoprotein(a) >50 mg/dL without baseline CVD. The results of this observational propensity-matched study require confirmation in studies with randomization of aspirin use.

Elevated lipoprotein(a) increases risk of subsequent major adverse cardiovascular events (MACE) and coronary revascularisation in incident ASCVD patients: A cohort study from the UK Biobank

BACKGROUND AND AIMS

Elevated lipoprotein(a) [Lp(a)] is a genetic driver for atherosclerotic cardiovascular disease (ASCVD). We aimed to provide novel insights into the associated risk of elevated versus normal Lp(a) levels on major adverse cardiovascular events (MACE) in an incident ASCVD cohort.

METHODS

This was an observational cohort study of incident ASCVD patients. MACE counts and incidence rates (IRs) per 100-person-years were reported for patients with normal (<65 nmol/L) and elevated (>150 nmol/L) Lp(a) within the first year after incident ASCVD diagnosis and overall follow-up. Cox proportional hazard models quantified the risk of MACE associated with a 100 nmol/L increase in Lp(a).

RESULTS

The study cohort included 32,537 incident ASCVD patients; 5204 with elevated and 22,257 with normal Lp(a). Of those with elevated Lp(a), 41.2% had a subsequent MACE, versus 35.61% with normal Lp(a). Within the first year of follow-up, the IRs of composite MACE and coronary revascularisation were significantly higher (p < 0.001) in patients with elevated versus normal Lp(a) (IR difference 6.79 and 4.66). This trend was also observed in the overall follow-up (median 4.7 years). Using time to first subsequent MACE, a 100 nmol/L increase in Lp(a) was associated with an 8.0% increased risk of composite MACE, and 18.6% increased risk of coronary revascularisation during the overall follow-up period.

CONCLUSIONS

The association of elevated Lp(a) with increased risk of subsequent MACE and coronary revascularisation highlights a population who may benefit from earlier and more targeted intervention for cardiovascular risk including Lp(a), particularly within the first year after ASCVD diagnosis. Proactive Lp(a) testing as part of routine clinical practice can help identify and better manage these higher-risk individuals.

Quantification of LDL-Cholesterol Corrected for Molar Concentration of Lipoprotein(a)

PURPOSE

Cholesterol in lipoprotein(a) [Lp(a)-C] is commonly estimated as 30% of the measured Lp(a) mass. However, difficulties in the accurate measurement of Lp(a) mass, along with the inaccuracy of the 30% assumption, produce erroneous values when LDL-C is corrected for Lp(a) [LDL-CLp(a)corr]. Our aim was to develop a new formula for LDL-CLp(a)corr to reduce this error.

METHODS

We developed a new formula to calculate Lp(a)-C from the molar measurement of Lp(a), which is Lp(a) nmol/L × 0.077 = Lp(a)-C mg/dL. The calculated Lp(a)-C is subtracted from LDL-C to obtain LDL-CLp(a)corr. The results obtained with our novel formula versus the conventional formula were compared in 440 samples from 239 participants enrolled in the BANTING study.

RESULTS

With the conventional formula, approximately 7% of samples with low LDL-C resulted in negative LDL-CLp(a)corr values. With the new formula, no negative LDL-CLp(a)corr values occurred. Among groups with the highest Lp(a)/apoB ratio (p < 0.001) and smaller apolipoprotein(a) isoform size (p < 0.006), LDL-CLp(a)corr was significantly underestimated by the conventional formula, which may result in the undertreatment of some patients.

CONCLUSION

The new formula provides more reliable estimates of LDL-CLp(a)corr than the conventional formula.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02739984.

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.

Predictive value of lipoprotein(a) for left atrial thrombus or spontaneous echo contrast in non-valvular atrial fibrillation patients with low CHA2DS2-VASc scores: a cross-sectional study

OBJECTIVE

Current guidelines are debated when it comes to starting anticoagulant therapy in patients with non-valvular atrial fibrillation (NVAF) and low CHA2DS2-VASc scores (1-2 in women and 0-1 in men). However, these individuals still have a high likelihood of developing left atrial thrombus/spontaneous echo contrast (LAT/SEC) and experiencing subsequent thromboembolism. Recent research has demonstrated that lipoprotein(a) [Lp(a)] may increase the risk of thrombosis, but the relationship between Lp(a) and LAT/SEC in NVAF patients is not clearly established. Therefore, this study sought to evaluate the predictive ability of Lp(a) for LAT/SEC among NVAF patients with low CHA2DS2-VASc scores.

METHODS

NVAF patients with available transesophageal echocardiography (TEE) data were evaluated. Based on the TEE results, the subjects were classified into non-LAT/SEC and LAT/SEC groups. The risk factors for LAT/SEC were examined using binary logistic regression analyses and were validated by using 1:1 propensity score matching (PSM). Subsequently, novel predictive models for LAT/SEC were developed by integrating the CHA2DS2-VASc score with the identified factors, and the accuracy of these models was tested using receiver operating characteristic (ROC) analysis.

RESULTS

In total, 481 NVAF patients were enrolled. The LAT/SEC group displayed higher Lp(a) concentrations. It was found that enlarged left atrial diameter (LAD), high concentrations of Lp(a), and a history of coronary heart disease (CHD) were independent predictors of LAT/SEC. Lp(a) and LAD still had predictive values for LAT/SEC after adjusting for PSM. In both the highest quartile groups of Lp(a) (>266 mg/L) and LAD (>39.5 mm), the occurrence of LAT/SEC was higher than that in the corresponding lowest quartile. By incorporating Lp(a) and the LAD, the predictive value of the CHA2DS2-VASc score for LAT/SEC was significantly improved.

CONCLUSION

Elevated Lp(a) and enlarged LAD were independent risk factors for LAT/SEC among NVAF patients with low CHA2DS2-VASc scores. The prediction accuracy of the CHA2DS2-VASc score for LAT/SEC was significantly improved by the addition of Lp(a) and LAD. When evaluating the stroke risk in patients with NVAF, Lp(a) and LAD should be taken into account together with the CHA2DS2-VASc score.

TRIAL REGISTRATION

Retrospectively registered.

High lipoprotein(a) concentration is associated with moyamoya disease

BACKGROUND

Moyamoya disease (MMD) has attracted the attention of scholars because of its rarity and unknown etiology.

METHODS

Data for this study were sourced from the Second Affiliated Hospital of Nanchang University. Regression analyses were conducted to examine the association in Lipoprotein [Lp(a)] and MMD. R and IBM SPSS were conducted.

RESULTS

A cohort comprising 1012 MMD patients and 2024 controls was established through the propensity score matching method. Compared with controls, MMD patients showed higher median Lp(a) concentrations [18.5 (9.6-37.8) mg/dL vs. 14.9 (7.8-30.5) mg/dL, P < 0.001]. The odds ratios and 95% confidence intervals for Lp(a) were calculated in three models: unadjusted model, model 1 (adjusted for body mass index and systolic blood pressure), and model 2 (adjusted for model 1 plus triglyceride, C-reactive protein, homocysteine, and low-density lipoprotein cholesterol). Results were [1.613 (1.299-2.002), P < 0.001], [1.598 (1.286-1.986), P < 0.001], and [1.661 (1.330-2.074), P < 0.001], respectively. Furthermore, age, sex, or hypertension status had nothing to do with this relationship.

CONCLUSIONS

Positive relationship exists between Lp(a) and MMD.

C-reactive protein modifies lipoprotein(a)-related risk for coronary heart disease: the BiomarCaRE project

BACKGROUND AND AIMS

Recent investigations have suggested an interdependence of lipoprotein(a) [Lp(a)]-related risk for cardiovascular disease with background inflammatory burden. The aim the present analysis was to investigate whether high-sensitive C-reactive protein (hsCRP) modulates the association between Lp(a) and coronary heart disease (CHD) in the general population.

METHODS

Data from 71 678 participants from 8 European prospective population-based cohort studies were used (65 661 without/6017 with established CHD at baseline; median follow-up 9.8/13.8 years, respectively). Fine and Gray competing risk-adjusted models were calculated according to accompanying hsCRP concentration (<2 and ≥2 mg/L).

RESULTS

Among CHD-free individuals, increased Lp(a) levels were associated with incident CHD irrespective of hsCRP concentration: fully adjusted sub-distribution hazard ratios [sHRs (95% confidence interval)] for the highest vs. lowest fifth of Lp(a) distribution were 1.45 (1.23-1.72) and 1.48 (1.23-1.78) for a hsCRP group of <2 and ≥2 mg/L, respectively, with no interaction found between these two biomarkers on CHD risk (Pinteraction = 0.82). In those with established CHD, similar associations were seen only among individuals with hsCRP ≥ 2 mg/L [1.34 (1.03-1.76)], whereas among participants with a hsCRP concentration <2 mg/L, there was no clear association between Lp(a) and future CHD events [1.29 (0.98-1.71)] (highest vs. lowest fifth, fully adjusted models; Pinteraction = 0.024).

CONCLUSIONS

While among CHD-free individuals Lp(a) was significantly associated with incident CHD regardless of hsCRP, in participants with CHD at baseline, Lp(a) was related to recurrent CHD events only in those with residual inflammatory risk. These findings might guide adequate selection of high-risk patients for forthcoming Lp(a)-targeting compounds.

Association between Lipoprotein(a) and diabetic nephropathy in patients with type 2 diabetes

Background

Diabetic nephropathy (DN) is one of the most prevalent and severe microvascular complications of type 2 diabetes (T2DM). However, little is currently known about the pathogenesis and its associated risk factors in DN. The present study aims to investigate the potential risk factors of DN in patients with T2DM.

Methods

A total of 6,993 T2DM patients, including 5,089 participants with DN and 1,904 without DN, were included in this cross-sectional study. Comparisons between the two groups (DN vs. non-DN) were carried out using Student's t-test, Mann-Whitney U-test, or Pearson's Chi-squared test. Spearman's correlation analyses were performed to assess the correlations of serum lipids and indicators of renal impairment. Logistic regression models were applied to assess the relationship between blood lipid indices and the presence of DN.

Results

T2DM patients with DN were older, and had a longer duration of diagnosed diabetes compared to those without DN. Of note, the DN patients also more likely develop metabolic disorders. Among all serum lipids, Lipoprotein(a) [Lp(a)] was the most significantly correlated indicators of renal impairment. Moreover, univariate logistic regression showed that elevated Lp(a) level was associated with an increased risk of DN. After adjusted for confounding factors, including age, gender, duration of T2DM, BMI, SBP, DBP and lipid-lowering drugs usage, Lp(a) level was independently positively associated with the risk of DN [odds ratio (OR):1.115, 95% confidence interval (CI): 1.079-1.151, P=6.06×10-11].

Conclusions

Overall, we demonstrated that serum Lp(a) level was significantly positively associated with an increased risk of DN, indicating that Lp(a) may have the potential as a promising target for the diagnosis and treatment of diabetic nephropathy.

Factors associated with the presence of tendon xanthomas in familial hypercholesterolemia

INTRODUCTION AND OBJECTIVES

Tendon xanthomas (TX) are lipid deposits highly specific to familial hypercholesterolemia (FH). However, there is significant variability in their presentation among FH patients, primarily due to largely unknown causes. Lipoprotein(a) is a well-established independent risk factor for atherosclerotic cardiovascular disease in the general population as well as in FH. Given the wide variability of lipoprotein(a) among FH individuals and the likelihood that TX may result from a proatherogenic and proinflammatory condition, the objective of this study was to analyze the size of TX in the Achilles tendons of FH participants and the variables associated with their presence, including lipoprotein(a) concentration.

METHODS

A cross-sectional study was conducted on 377 participants with a molecular diagnosis of heterozygous FH. Achilles tendon maximum thickness (ATMT) was measured using ultrasonography with standardized equipment and procedures. Demographic variables and lipid profiles were collected. A multivariate linear regression model using a log-Gaussian approach was used to predict TX size. Classical cardiovascular risk factors and lipoprotein(a) were included as explanatory variables.

RESULTS

The mean low-density lipoprotein cholesterol level was 277mg/dL without lipid-lowering treatment, and the median ATMT was 5.50mm. We demonstrated that age, sex, low-density lipoprotein cholesterol, and lipoprotein(a) were independently associated with ATMT. However, these 4 variables did not account for most the interindividual variability observed (R2=0.205).

CONCLUSIONS

TX, a characteristic hallmark of FH, exhibit heterogeneity in their presentation. Interindividual variability can partially be explained by age, male sex, low-density lipoprotein cholesterol, and lipoprotein(a) but these factors account for only 20% of this heterogeneity.

Association of Renal Function and Statin Therapy with Lipoprotein(a) in Patients with Type 2 Diabetes

AIM

A high level of serum lipoprotein(a) [Lp(a)] is associated with kidney disease development in patients with type 2 diabetes (T2DM). Recent studies have suggested that statins may affect serum levels of Lp(a). However, the statin effect is not well-defined in patients with T2DM with kidney dysfunction. This retrospective study aimed to investigate the relevance of kidney dysfunction and statin therapy to Lp(a) in patients with T2DM.

METHODS

Japanese patients with T2DM (n=149, 96 men and 53 women) were divided into two groups: statin users (n=79) and non-statin users (n=70). Multiple logistic regression analyses were performed with Lp(a) as the objective variable and estimated glomerular filtration rate (eGFR), hemoglobin A1c, age, gender, and body mass index as the explanatory variables.

RESULTS

Lp(a) serum levels were higher in statin users than in non-statin users (P=0.022). Multivariate regression analysis results showed an inverse correlation of eGFR to log Lp(a) in all patients (P=0.009) and in non-statin users (P=0.025), but not in statin users. In a multiple logistic regression analysis for median Lp(a), there was an inverse association between eGFR and Lp(a) level (odds ratio, 0.965; 95% confidence interval, 0.935-0.997; P=0.030) in non-statin users as well as in all participants, but not in statin users.

CONCLUSIONS

The present study suggests that a high Lp(a) level in patients with T2DM, except in statin users, is significantly associated with decreased eGFR, indicating that the increased Lp(a) levels under statin therapy might diminish the relationship between Lp(a) and eGFR.

The impact of baseline dietary fatty acid intake on the association between lipoprotein(a) and mortality in two US cohorts

Background

Lipoprotein(a) (Lp(a)) is an established casual risk factor for atherosclerotic cardiovascular disease. It remains unknown whether dietary fat modifies the association of Lp(a) with cardiovascular death.

Aim

To understand if dietary fat modifies the association between Lp(a) and cardiovascular death.

Methods

We utilized the Atherosclerotic Risk in Communities (ARIC) study and National Health and Nutrition Examination Survey (NHANES) III cohorts and used multivariate cox proportional hazard modeling to test the association between Lp(a), dietary fats, and cardiovascular death.

Results

The sample (n = 22,805) had average age 51.3 years and was mostly female (55.4%). Lp(a) ≥ 30 mg/dL was associated with CV death in both ARIC (1.36, p = 0.001) and NHANES (1.31, p = 0.03). In multivariate analysis, no categorical or individual fatty acids modified the association between Lp(a) and CV death.

Conclusion

There was no evidence that baseline dietary fat intake modified the association between Lp(a) and CV death.

Cascade testing of children and adolescents for elevated Lp(a) in pedigrees with familial hypercholesterolaemia

Elevated plasma lipoprotein(a) [Lp(a)] is a common, inherited condition independently causing cardiovascular disease. Recent expert recommendations suggest opportunistically testing for elevated Lp(a) during cascade testing for familial hypercholesterolaemia (FH). We investigated the effectiveness of detecting elevated Lp(a) in 103 children and adolescents who were first-degree relatives of 66 adult index FH cases as part of an established FH cascade screening program. The yield of detection of elevated Lp(a) using a threshold of ≥30 mg/dL in children and adolescents was assessed. Cascade testing from FH index cases with elevated Lp(a) ≥50 mg/dL identified 1 case of Lp(a) ≥30 mg/dL for every 2 children or adolescents tested. In contrast, opportunistic screening from index cases with FH but normal Lp(a) levels demonstrated 1 case of Lp(a) ≥30 mg/dL for every 7.5 children or adolescents tested (p < 0.001). In conclusion, cascade testing for elevated Lp(a) from index cases with FH and elevated Lp(a) is effective in identifying new cases of elevated Lp(a).

Clinical-epidemiological analysis of patients with elevated lipoprotein A in a third level hospital

OBJECTIVE

The objective of the study is to describe the clinical and epidemiological characteristics of our patients with elevated Lp(a).

MATERIALS AND METHODS

A descriptive cross-sectional study was conducted on 316 patients with elevated Lp(a) (>125 nmol/L) in a random sample between January and August 2022. We measured epidemiological, anthropometric, clinical and laboratory variables (lipid metabolism parameters, carbohydrates and hormones).

RESULTS

Mean age of our sample subject's was 59 ± 15 years with 56% males. The average BMI was 27.6 kg/m2 (71% with elevated BMI). Elevated waist circumference was observed in 54.1% of men and 77.8% of women. 48% had hypertension, 30.7% had diabetes mellitus and 91.5% dyslipidemia. Only 39.7% of the patients had never smoked. The mean values of total cholesterol were 158 ± 45 mg/dl, LDL was 81 ± 39 mg/dl, HDL was 53 ± 17 mg/dl, Triglycerides were 127 ± 61 mg/dl, and Lp(a) was 260 ± 129 nmol/L. Regarding lipid lowering treatment, 89% were on statins, 68.6% on ezetimibe, and 13.7% on PCSK9 inhibitors. 177 patients (57,7%) had established cardiovascular disease (CVD), 16.3% had polyvascular disease, 11.7% had subclinical CVD, and 30.6% had no known CVD. Among patients with established CVD, 174 (98.3%) were on lipid-lowering treatment (97.2% on statins) and 86.4% were on antiplatelet therapy. The mean age of cardiovascular events was 55 ± 12 years in males and 60 ± 11 years in females. 65,1% of female and 56,2% of male patients suffered an early cardiovascular event.

CONCLUSIONS

Patients with elevated Lp(a) are at very high cardiovascular risk, particularly for early cardiovascular disease.

Association between serum lipoprotein(a) and mildly reduced eGFR: a cross-sectional study

Lipoprotein(a) [Lp(a)] is a risk factor for cardiovascular disease (CVD) and aortic stenosis. However, the data on the relationship between Lp(a) and mildly reduced estimated glomerular filtration rate (eGFR) has been disputed. This study was conducted to assess the relationship between Lp(a) concentrations and mildly reduced eGFR in healthy subjects.This community-based, cross-sectional study enrolled 1,064 volunteers aged ≥ 40 years who lived in Yonghong Community, Zhonglou District, Changzhou, China, between December 2016 and December 2017. A mildly reduced eGFR was defined as eGFR between 60 and 90 mL/min/1.73m2. A standardized questionnaire and biochemical measurements were used to gather information about participants. The serum concentration of Lp(a) was determined using the latex-enhanced immunoturbidimetric test. Of the total study population, 34.8% (n = 370) were men, and the mean age was 66.8 ± 8.5 years. A significant association existed between Lp(a) levels and the risk of mildly reduced eGFR. Individuals with the highest tertile of Lp(a) had higher odds of mildly reduced eGFR after adjusting for various confounders (adjusted odds ratio [OR]: 1.80, 95% confidence interval [CI]: 1.24-2.60, P = 0.0025) compared to those with the lowest tertile of Lp(a). Multivariable logistic regression of studies in which Lp(a) was presented as continuous variables showed consistent results (adjusted OR: 1.23 for 1-SD increment of Ln-Lp(a), 95% CI: 1.05-1.43). Subgroup analyses showed that study characteristics such as age, sex, obesity, diabetes, and hypertension status did not significantly affect the association (P for all interactions > 0.05). These results suggest that higher serum Lp(a) level was an independent risk factor for mildly reduced eGFR.

Serum lipoprotein(a) and reclassification of coronary heart disease risk; application of prediction in a cross-sectional analysis of an ongoing Iranian cohort

INTRODUCTION

Recent studies have introduced elevated lipoprotein(a) (Lp(a)) as a risk factor for coronary heart disease (CHD). This study investigated whether the addition of Lp(a) as a novel biomarker to the Framingham Risk Score (FRS) model improves CHD risk prediction.

METHODS

The study included 1101 Iranian subjects (443 non-diabetic and 658 diabetic patients) who were followed for 10 years (2003-2013). Lp(a) levels and CHD events were recorded for each participant.

RESULTS

The Net Reclassification Index (NRI) after adding Lp(a) to the FRS model was 19.57% and the discrimination slope was improved (0.160 vs. 0.173). The Akaike Information Criterion (AIC), a measure of model complexity, decreased significantly after adding Lp(a) to the FRS model (691.9 vs. 685.4, P value: 0.007).

CONCLUSIONS

The study concluded that adding Lp(a) to the FRS model improves CHD risk prediction in an Iranian population without making the model too complex. This could help clinicians to better identify individuals who are at risk of developing CHD and to implement appropriate preventive measures.

Emerging therapies in dyslipidaemias

Several observations have shown that elevated levels of low-density lipoprotein cholesterol (LDL-C) are a cause of cardiovascular disease. Lowering LDL-C is a key strategy for reducing cardiovascular risk, with a continuous linear correlation between LDL-C reduction and cardiovascular benefit. Based on these observations, current guidelines have further lowered LDL-C goals and call for the use of more effective therapeutic interventions. In addition to statins, ezetimibe and the monoclonal antibodies targeting PCSK9, several new lipid-lowering agents are currently in phase 3 clinical trials to evaluate their clinical effects, and more are in development. The use of combination therapies targeting different pathways can increase the effectiveness of treatment.

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), Interleukin-6 inhibitors, and atherosclerotic cardiovascular disease: Is there an association?

Background and aims

Lipoprotein(a) [Lp(a)] and interleuking-6 (IL-6), an inflammation biomarker, have been established as distinct targets of the residual atherosclerotic cardiovascular disease (ASCVD) risk. We aimed to investigate the association between them, and the potential clinical implications in ASCVD prevention.

Methods

A literature search was conducted in PubMed until December 31st, 2022, using relevant keywords.

Results

Elevated lipoprotein(a) [Lp(a)] levels constitute the most common inherited lipid disorder associated with ASCVD. Although Lp(a) levels are mostly determined genetically by the LPA gene locus, they may be altered by acute conditions of stress and chronic inflammatory diseases. Considering its resemblance with low-density lipoproteins, Lp(a) is involved in atherosclerosis, but it also exerts oxidative, thrombotic, antifibrinolytic and inflammatory properties. The cardiovascular efficacy of therapies lowering Lp(a) by >90% is currently investigated. On the other hand, interleukin (IL)-1b/IL-6 pathway also plays a pivotal role in atherosclerosis and residual ASCVD risk. IL-6 receptor inhibitors [IL-6(R)i] lower Lp(a) by 16-41%, whereas ongoing trials are investigating their potential anti-atherosclerotic effect. The Lp(a)-lowering effect of IL-6(R)i might be attributed to the inhibition of the IL-6 response elements in the promoter region of the LPA gene.

Conclusions

Although the effect of IL-6(R)i on Lp(a) levels is inferior to that of available Lp(a)-lowering therapies, the dual effect of the former on both inflammation and apolipoprotein (a) synthesis may prove of equal or even greater significance when it comes ASCVD outcomes. More trials are required to establish IL-6(R)i in ASCVD prevention and elucidate their interplay with Lp(a) as well as its clinical significance.

Genetic variation in solute carrier family 5 member 2 mimicking sodium-glucose co-transporter 2-inhibition and risk of cardiovascular disease and all-cause mortality: reduced risk not explained by lower plasma glucose

AIMS

Treatment with sodium-glucose co-transporter 2 (SGLT2)-inhibitors reduces the risk of cardiovascular disease and mortality, but the mechanism is unclear. We hypothesized that a functional genetic variant in solute carrier family 5 member 2 (SLC5A2), known to be associated with familial renal glucosuria, would mimic pharmacological SGLT2-inhibition, and thus provide an opportunity to examine potential mediators of the effects on lower risk of cardiovascular disease and mortality.

METHODS AND RESULTS

We examined 112 712 individuals from the Copenhagen City Heart Study and Copenhagen General Population Study (CCHS + CGPS), 488 687 from the UK Biobank, and 342 499 from FinnGen, genotyped for SLC5A2 rs61742739, c.1961A > G; p.(Asn654Ser). The 2.0% heterozygotes and 0.01% homozygotes were pooled as carriers and compared with the 98% non-carriers. First, we examined the risk of cardiovascular disease and mortality; second, whether carrying the variant was associated with potential mediators of the effect; and third, whether identified potential mediators could explain the observed reduced risk of cardiovascular disease and mortality. In the CCHS + CGPS, carriers vs. non-carries had a 31% lower risk of heart failure, 21% lower risk of myocardial infarction, 16% lower risk of ischaemic heart disease, and 22% lower risk of all-cause mortality. Corresponding values in meta-analyses of the three studies combined were lower risk by 10%, 6%, 6%, and 10%, respectively. The SLC5A2 rs61742739 variant was not associated with a risk of ischaemic stroke or cardiovascular mortality. Of the lower risks observed in CCHS + CGPS, lower plasma glucose mediated 2.0%(P = 0.004) on heart failure, 3.1%(P = 0.09) on myocardial infarction, 4.1%(P = 0.02) on ischaemic heart disease, and 6.0%(P = 0.39) on all-cause mortality; corresponding values in the UK Biobank were 2.9%(P = 0.70), 1.5%(P = 0.77), 4.1%(P = 0.23), and 3.1%(P = 0.21), respectively.

CONCLUSION

A functional genetic variant in SLC5A2, mimicking SGLT2-inhibition, was associated with a lower risk of heart failure, myocardial infarction, ischaemic heart disease, and all-cause mortality. These effects were at most minimally mediated through lower plasma glucose.

Prevalence of lipoprotein(a) measurement in patients with or at risk of cardiovascular disease

INTRODUCTION

Lipoprotein(a) [Lp(a)] is a genetically determined independent risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valve disease. Despite recommendations from professional societies in the cardiovascular field, the awareness of elevated Lp(a) as a risk factor and screening for Lp(a) are suspected to be low.

METHODS

We conducted a retrospective, observational case control study of patient charts from January 1, 2017 to June 19, 2022. The primary aims were 1) to describe the proportion of patients at the healthcare network's primary care and cardiology clinics that met Lp(a) screening criteria and were tested; and 2) to describe the proportion of patients throughout the entire healthcare network that had Lp(a) measured.

RESULTS

Of the 2,412,020 patient charts in the health network, only 5,942 (0.25 %) had Lp(a) measured. Of the 84,581 patients in primary care or cardiology clinics who met screening criteria, only 1,311 (1.55 %) had Lp(a) measured. Patients with Lp(a) measured were more likely to be younger, non-Hispanic/Latinx, had a lipid panel measured, a cardiac computed tomography (CT) imaging study, and higher low-density lipoprotein-cholesterol. Patients with ASCVD, heart failure, ischemic heart disease, aortic stenosis, peripheral vascular disease, or a stroke did not feature highly among patients who received Lp(a) testing. Having an abnormal or risk-enhancing Lp(a) level was associated with being female and/or being Black/African American.

CONCLUSIONS

Despite increased awareness of Lp(a) and its contribution to cardiovascular disease there exists a paucity of testing. Increased Lp(a) testing can identify patients who have an increased cardiovascular risk underestimated by other metrics.

Frequency of lipoprotein(a) measurements in patients with or at risk of cardiovascular disease

Knowledge of lipoprotein(a) measurement in community practice is limited. The objective of this study is to evaluate the frequency of Lp(a) screening across the University of Rochester Medical Center (URMC). Descriptive data were collected for all URMC patients >= 18 years old who have had at least one Lp(a) measurement from January 2011 to August 2022 from the URMC electronic health record (EHR). Cardiovascular diagnoses were queried to define yearly frequency and demographic information. We identified 2,698 patients with at least one Lp(a) result. An increasing number of patients were tested per year. There were more women than men, and about 11% having more than one Lp(a) measured with the majority having a level <30 mg/dL (the normal-range in the UMRC lab). The majority do not have a listed diagnosis of cerebral infarction, peripheral vascular disease, myocardial infarction, coronary artery disease, or aortic stenosis. Across URMC, there has been a steady increase of Lp(a) measurements in the past several years.

Secondary Prevention and Extreme Cardiovascular Risk Evaluation (SEVERE-1), Focus on Prevalence and Associated Risk Factors: The Study Protocol

INTRODUCTION

Despite significant improvement in secondary CardioVascular (CV) preventive strategies, some acute and chronic coronary syndrome (ACS and CCS) patients will suffer recurrent events (also called "extreme CV risk"). Recently new biochemical markers, such as uric acid (UA), lipoprotein A [Lp(a)] and several markers of inflammation, have been described to be associated with CV events recurrence. The SEcondary preVention and Extreme cardiovascular Risk Evaluation (SEVERE-1) study will accurately characterize extreme CV risk patients enrolled in cardiac rehabilitation (CR) programs.

AIM

 Our aims will be to describe the prevalence of extreme CV risk and its association with newly described biochemical CV risk factors.

AIM

Our aims will be to describe the prevalence of extreme CV risk and its association with newly described biochemical CV risk factors.

METHODS

We will prospectively enrol 730 ACS/CCS patients at the beginning of a CR program. Extreme CV risk will be retrospectively defined as the presence of a previous (within 2 years) CV events in the patients' clinical history. UA, Lp(a) and inflammatory markers (interleukin-6 and -18, tumor necrosis factor alpha, C-reactive protein, calprotectin and osteoprotegerin) will be assessed in ACS/CCS patients with extreme CV risk and compared with those without extreme CV risk but also with two control groups: 1180 hypertensives and 765 healthy subjects. The association between these biomarkers and extreme CV risk will be assessed with a multivariable model and two scoring systems will be created for an accurate identification of extreme CV risk patients. The first one will use only clinical variables while the second one will introduce the biochemical markers. Finally, by exome sequencing we will both evaluate polygenic risk score ability to predict recurrent events and perform mendellian randomization analysis on CV biomarkers.

CONCLUSIONS

Our study proposal was granted by the European Union PNRR M6/C2 call. With this study we will give definitive data on extreme CV risk prevalence rising attention on this condition and leading cardiologist to do a better diagnosis and to carry out a more intensive treatment optimization that will finally leads to a reduction of future ACS recurrence. This will be even more important for cardiologists working in CR that is a very important place for CV risk definition and therapies refinement.

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.

High levels of lipoprotein(a) in transgenic mice exacerbate atherosclerosis and promote vulnerable plaque features in a sex-specific manner

BACKGROUND AND AIMS

Despite increased clinical interest in lipoprotein(a) (Lp(a)), many questions remain about the molecular mechanisms by which it contributes to atherosclerotic cardiovascular disease. Existing murine transgenic (Tg) Lp(a) models are limited by low plasma levels of Lp(a) and have not consistently shown a pro-atherosclerotic effect of Lp(a).

METHODS

We generated Tg mice expressing both human apolipoprotein(a) (apo(a)) and human apoB-100, with pathogenic levels of plasma Lp(a) (range 87-250 mg/dL). Female and male Lp(a) Tg mice (Tg(LPA+/0;APOB+/0)) and human apoB-100-only controls (Tg(APOB+/0)) (n = 10-13/group) were fed a high-fat, high-cholesterol diet for 12 weeks, with Ldlr knocked down using an antisense oligonucleotide. FPLC was used to characterize plasma lipoprotein profiles. Plaque area and necrotic core size were quantified and immunohistochemical assessment of lesions using a variety of cellular and protein markers was performed.

RESULTS

Male and female Tg(LPA+/0;APOB+/0) and Tg(APOB+/0) mice exhibited proatherogenic lipoprotein profiles with increased cholesterol-rich VLDL and LDL-sized particles and no difference in plasma total cholesterol between genotypes. Complex lesions developed in the aortic sinus of all mice. Plaque area (+22%), necrotic core size (+25%), and calcified area (+65%) were all significantly increased in female Tg(LPA+/0;APOB+/0) mice compared to female Tg(APOB+/0) mice. Immunohistochemistry of lesions demonstrated that apo(a) deposited in a similar pattern as apoB-100 in Tg(LPA+/0;APOB+/0) mice. Furthermore, female Tg(LPA+/0;APOB+/0) mice exhibited less organized collagen deposition as well as 42% higher staining for oxidized phospholipids (OxPL) compared to female Tg(APOB+/0) mice. Tg(LPA+/0;APOB+/0) mice had dramatically higher levels of plasma OxPL-apo(a) and OxPL-apoB compared to Tg(APOB+/0) mice, and female Tg(LPA+/0;APOB+/0) mice had higher plasma levels of the proinflammatory cytokine MCP-1 (+3.1-fold) compared to female Tg(APOB+/0) mice.

CONCLUSIONS

These data suggest a pro-inflammatory phenotype exhibited by female Tg mice expressing Lp(a) that appears to contribute to the development of more severe lesions with greater vulnerable features.

The Promise of PCSK9 and Lipoprotein(a) as Targets for Gene Silencing Therapies

PURPOSE

High plasma concentrations of LDL and lipoprotein(a) (Lp[a]) are independent and causal risk factors for atherosclerotic cardiovascular disease (ASCVD). There is an unmet therapeutic need for high-risk patients with elevated levels of LDL-C and/or Lp(a). Recent advances in the development of nucleic acids for gene silencing (ie, triantennary N-acetylgalactosamine conjugated antisense-oligonucleotides [ASOs] and small interfering RNA [siRNA]) targeting proprotein convertase subtilisin/kexin type 9 (PCSK9) and Lp(a) offer effective and sustainable therapies.

METHODS

Related articles in the English language were identified through a search for original and review articles in the PubMed database using the following key terms: cardiovascular disease, dyslipidemia, PCSK9 inhibitors, Lp(a), LDL-cholesterol, familial hypercholesterolemia, siRNA, and antisense oligonucleotide and clinical trials (either alone or in combination).

FINDINGS

Inclisiran, the most advanced siRNA-treatment targeting hepatic PCSK9, is well tolerated, producing a >30% reduction on LDL-C levels in randomized controlled trials. Pelacarsen is the most clinical advanced ASO, whereas olpasiran and SLN360 are the 2 siRNAs directed against the mRNA of the LPA gene. Evidence suggests that all Lp(a)-targeting agents are safe and well tolerated, with robust and sustained reduction in plasma Lp(a) concentration up to 70% to 90% in individuals with elevated Lp(a) levels.

IMPLICATIONS

Cumulative evidence from clinical trials supports the value of ASO and siRNA therapies targeting the synthesis of PCSK9 and Lp(a) for lowering LDL-C and Lp(a) in patients with established ASCVD or high risk of ASCVD. Further research is needed to examine whether gene silencing therapy could improve clinical outcomes in patients with elevated LDL and/or Lp(a) levels. Confirmation of the tolerability and cost-effectiveness of long-term inhibition of PCSK9 and Lp(a) with this approach is essential.

Women, lipids, and atherosclerotic cardiovascular disease: a call to action from the European Atherosclerosis Society

Cardiovascular disease is the leading cause of death in women and men globally, with most due to atherosclerotic cardiovascular disease (ASCVD). Despite progress during the last 30 years, ASCVD mortality is now increasing, with the fastest relative increase in middle-aged women. Missed or delayed diagnosis and undertreatment do not fully explain this burden of disease. Sex-specific factors, such as hypertensive disorders of pregnancy, premature menopause (especially primary ovarian insufficiency), and polycystic ovary syndrome are also relevant, with good evidence that these are associated with greater cardiovascular risk. This position statement from the European Atherosclerosis Society focuses on these factors, as well as sex-specific effects on lipids, including lipoprotein(a), over the life course in women which impact ASCVD risk. Women are also disproportionately impacted (in relative terms) by diabetes, chronic kidney disease, and auto-immune inflammatory disease. All these effects are compounded by sociocultural components related to gender. This panel stresses the need to identify and treat modifiable cardiovascular risk factors earlier in women, especially for those at risk due to sex-specific conditions, to reduce the unacceptably high burden of ASCVD in women.

Is Lipoprotein(a) Clinically Actionable with Today's Evidence? The Answer is Yes

PURPOSE OF REVIEW

Lipoprotein(a) is an independent risk factor for cardiovascular disease. We review the ongoing shifts in consensus guidelines for the testing and management of Lp(a) and provide insight into whether current evidence suggests that awareness and testing of Lp(a) is clinically actionable.

RECENT FINDINGS

GWAS and Mendelian randomization studies have established causal links between elevated Lp(a) and forms of CVD, including CAD and calcific aortic valve disease. Testing of Lp(a) identifies patients with similar risk to that of heterozygous FH, enhances risk stratification in patients with borderline/intermediate risk as determined through traditional factors, and facilitates the assessment of inherited CVD risk through cascade screening in patients with known family history of elevated Lp(a). Reductions in Lp(a) through non-targeted therapies including PCSK9 inhibition and lipoprotein apheresis have demonstrated reductions in ASCVD risk that are likely attributable to lowering Lp(a). Targeted therapies to potently lower Lp(a) are in clinical development. Lp(a) is actionable, and can be used to identify high risk patients for primary prevention and their family members through cascade screening, and to guide intensification of therapy in primary and secondary prevention of ASCVD.

Consensus document on Lipoprotein(a) from the Italian Society for the Study of Atherosclerosis (SISA)

AIMS

In view of the consolidating evidence on the causal role of Lp(a) in cardiovascular disease, the Italian Society for the Study of Atherosclerosis (SISA) has assembled a consensus on Lp(a) genetics and epidemiology, together with recommendations for its measurement and current and emerging therapeutic approaches to reduce its plasma levels. Data on the Italian population are also provided.

DATA SYNTHESIS

Lp(a) is constituted by one apo(a) molecule and a lipoprotein closely resembling to a low-density lipoprotein (LDL). Its similarity with an LDL, together with its ability to carry oxidized phospholipids are considered the two main features making Lp(a) harmful for cardiovascular health. Plasma Lp(a) concentrations vary over about 1000 folds in humans and are genetically determined, thus they are quite stable in any individual. Mendelian Randomization studies have suggested a causal role of Lp(a) in atherosclerotic cardiovascular disease (ASCVD) and aortic valve stenosis and observational studies indicate a linear direct correlation between cardiovascular disease and Lp(a) plasma levels. Lp(a) measurement is strongly recommended once in a patient's lifetime, particularly in FH subjects, but also as part of the initial lipid screening to assess cardiovascular risk. The apo(a) size polymorphism represents a challenge for Lp(a) measurement in plasma, but new strategies are overcoming these difficulties. A reduction of Lp(a) levels can be currently attained only by plasma apheresis and, moderately, with PCSK9 inhibitor treatment.

CONCLUSIONS

Awaiting the approval of selective Lp(a)-lowering drugs, an intensive management of the other risk factors for individuals with elevated Lp(a) levels is strongly recommended.

Lipoprotein(a) in patients with breast cancer after chemotherapy: exploring potential strategies for cardioprotection

Developments in neoadjuvant and adjuvant chemotherapy (CHT) have led to an increase in the number of breast cancer survivors. The determination of an appropriate follow-up for these patients is of increasing importance. Deaths due to cardiovascular disease (CVD) are an important part of mortality in patients with breast cancer.This review suggests that chemotherapeutic agents may influence lipoprotein(a) (Lp(a)) concentrations in breast cancer survivors after CHT based on many convincing evidence from epidemiologic and observational researches. Usually, the higher the Lp(a) concentration, the higher the median risk of developing CVD. However, more clinical trial results are needed in the future to provide clear evidence of a possible causal relationship. This review also discuss the existing and emerging therapies for lowering Lp(a) concentrations in the clinical setting. Hormone replacement therapy, statins, proprotein convertase subtilisin/kexin-type 9 (PCSK9) inhibitors, Antisense oligonucleotides, small interfering RNA, etc. may reduce circulating Lp(a) or decrease the incidence of CVD.

Hypertensive Disorders of Pregnancy: Assessing the Significance of Lp(a) and ApoB Concentrations in a Romanian Cohort

Background: This research delves into the association between altered lipid profiles and hypertensive disorders of pregnancy (HDP), shedding light on cardiovascular implications in maternal health. Methods: A cohort of 83 pregnant women was studied, with 48.19% diagnosed with HDP. This investigation primarily focused on Apolipoprotein B (ApoB) and Lipoprotein(a) (Lp(a)) as indicators of cardiovascular health. A comparative examination was conducted to determine discrepancies in the ApoB and Lp(a) levels between standard pregnancies and those presenting with HDP. Results: Significant elevations in ApoB (p value = 0.0486) and Lp(a) (p value < 0.0001) levels were observed in pregnant women with HDP compared to their counterparts with typical pregnancies. The pronounced link between heightened ApoB and Lp(a) concentrations and HDP persisted, even considering pregnancy's distinct physiological conditions. Conclusions: Our research accentuates the crucial role of early detection and specialized handling of cardiovascular risks in expectant mothers, especially those predisposed to HDP. The study indicates ApoB and Lp(a)'s potential as reliable markers for gauging cardiovascular threats during gestation. Furthermore, our findings suggest an integrative care approach and guidance for pregnant women, aspiring to enhance cardiovascular health in the postpartum phase.

Association between lipoprotein(a) and ischemic stroke: Fibrinogen as a mediator

BACKGROUND

Previous studies have reported lipoprotein(a) was related to increased risk of ischemic stroke. However, the role of fibrinogen in their associations was not fully elucidated.

AIM

We aimed to investigate the mediating role of fibrinogen in the association between lipoprotein(a) and risk of ischemic stroke.

METHODS

A total of 516 patients with ischemic stroke were matched 1:1 to patients without ischemic stroke for age and gender. Serum lipoprotein(a) and plasma fibrinogen levels were collected on the basis of the results of biochemical tests. Multivariate conditional logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for lipoprotein(a) levels and ischemic stroke risk. Mediation analysis were further conducted to evaluate the potential mediating role of fibrinogen in the association between lipoprotein(a) and ischemic stroke risk.

RESULTS

The lipoprotein(a) level of subjects with ischemic stroke was significantly higher than that of subjects without ischemic stroke (P < 0.001). Each SD increment of lipoprotein(a) was associated with 27% higher odds (OR 1.27, 95%CI: 1.11, 1.45) increment in ORs of ischemic stroke. Furthermore, mediation analyses indicated that fibrinogen mediated 10.15% of the associations between lipoprotein(a) and ischemic stroke.

CONCLUSIONS

Higher level of lipoprotein(a) was independently associated with increased risk of ischemic stroke and fibrinogen partially mediated the associations of lipoprotein(a) and ischemic stroke risk.