Lipoprotein(a): A Genetically Determined, Causal, and Prevalent Risk Factor for Atherosclerotic Cardiovascular Disease: A Scientific Statement From the American Heart Association

Association of lipoprotein(a) with left ventricular hypertrophy in patients with new-onset acute myocardial infarction: A large cross-sectional study

BACKGROUND

The association of lipoprotein(a) [Lp(a)] with echocardiography-estimated left ventricular hypertrophy (LVH) in high-risk population remains uncertain, so we assessed the association between Lp(a) with echocardiography-derived LVH in patients with new-onset acute myocardial infarction (AMI).

METHODS

In this large, single-center, cross-sectional observational study, we enrolled 2,096 patients with new-onset AMI. Lp(a) was used as the independent variable and LVH was used as the dependent variable. Logistic regression, subgroup and sensitivity analysis were performed to test the association of Lp(a) with LVH.

RESULTS

The concentration of Lp(a) was higher in LVH group compared with the non-LVH group (P < 0.001). Multivariate logistic regression analysis showed that higher Lp(a) was strongly associated with higher risk of LVH, independently of traditional cardiovascular risk factors (Fully adjusted model, Q4 vs Q1, OR: 1.941, 95% CI: 1.343-2.803, P < 0.001). Subgroup analysis showed that the association of Lp(a) with LVH persisted in the subgroups of age (<60 and ≥60 years), sex (male and female), smoking (yes and no), diabetes (yes), hypertension (yes), hyperlipidemia (yes), and chronic kidney diseases (yes and no). Further sensitivity analysis indicated that Lp(a) remained significantly associated with LVH after further adjusting for high-sensitivity C-reactive protein or excluding patients with estimated glomerular filtration rate < 30 ml/min/1.73 m² or dividing Lp(a) into multiple dichotomous variables.

CONCLUSION

Lp(a) was closely associated with LVH in patients with new-onset AMI.

Association of lipoprotein(a) with coronary severity in patients with new-onset acute myocardial infarction: A large cross-sectional study

BACKGROUND

Although current evidence suggests a causal association between lipoprotein(a) [Lp(a)] and cardiovascular disease, there is still no consensus on its association with coronary severity in new-onset acute myocardial infarction (AMI). We explored the association of Lp(a) with coronary severity.

METHODS

In this large cross-sectional study, we enrolled 2,740 patients with new-onset AMI from the Zhongda Hospital affiliated to Southeast University. Lp(a) was considered as an exposure variable. Gensini score, left main disease and three-vessel disease were used to assess coronary severity. Multivariate logistic regression, restricted cubic spline (RCS) models and threshold effects were used to analyze the association of Lp(a) with coronary severity.

RESULTS

Multivariate adjusted models showed that Lp(a) was independently associated with Gensini score (≥100), left main disease and three-vessel disease [Q4 vs Q1, OR (95 % CI), P value: 2.301 (1.770, 2.992), P < 0.001; 1.743 (1.174, 2.587), P = 0.006; 1.431 (1.128, 1.816), P = 0.003; respectively], and the associations persisted in sensitivity analyses and most subgroups (P < 0.05). Additionally, the RCS showed that Lp(a) was nonlinearly associated with Gensini score (continuous variable), Gensini score (≥100) and three-vessel disease (P for nonlinearity < 0.05). Threshold effects analysis showed that Lp(a) above the inflection point was positively associated with Gensini score (continuous variable) as well as the risk of Gensini score (≥100) and three-vessel disease.

CONCLUSION

Lp(a) was closely associated with coronary severity represented by Gensini score, left main disease and three-vessel disease in patients with new-onset AMI.

Elevated Lp(a) Levels Correlate with Severe and Multiple Coronary Artery Stenotic Lesions

Backgrounds and Aims

The role of Lipoprotein(a) (Lp(a)) in increasing the risk of cardiovascular diseases is reported in several populations. The aim of this study is to investigate the correlation of high Lp(a) levels with the degree of coronary artery stenosis.

Methods

Two hundred and sixty-eight patients were enrolled for this study. Patients who underwent coronary artery angiography and who had Lp(a) measurements available were included in this study. Binomial logistic regressions were applied to investigate the association between Lp(a) and stenosis in the four major coronary arteries. The effect of LDL and HDL Cholesterol on modulating the association of Lp(a) with coronary artery disease (CAD) was also evaluated. Multinomial regression analysis was applied to assess the association of Lp(a) with the different degrees of stenosis in the four major coronary arteries.

Results

Our analyses showed that Lp(a) is a risk factor for CAD and this risk is significantly apparent in patients with HDL-cholesterol ≥35 mg/dL and in non-obese patients. A large proportion of the study patients with elevated Lp(a) levels had CAD even when exhibiting high HDL serum levels. Increased HDL with low Lp(a) serum levels were the least correlated with stenosis. A significantly higher levels of Lp(a) were found in patients with >50% stenosis in at least two major coronary vessels arguing for pronounced and multiple stenotic lesions. Finally, the derived variant (rs1084651) of the LPA gene was significantly associated with CAD.

Conclusion

Our study highlights the importance of Lp(a) levels as an independent biological marker of severe and multiple coronary artery stenosis.

Predictive effect of different blood lipid parameters combined with carotid intima-media thickness on coronary artery disease

Background

Blood lipids disorder and atherosclerosis are closely related to coronary artery disease (CAD). This study aims to compare different blood lipid parameters combined with carotid intima-media thickness (cIMT) in predicting CAD.

Methods

This was a retrospective study including patients who underwent coronary angiography for highly suspected CAD. Blood samples were taken for lipid profile analysis and cIMT was evaluated by carotid ultrasound. Logistic analysis was used to establish different models of different lipid parameters in predicting CAD. The area under the receiver operating characteristic curve (AUC) was used to examine the predictive value. The optimal lipid parameter was also used to explore the relationship with multi-vessel CAD.

Results

Patients were classified into two groups based on whether CAD existed. Compared with non-CAD patients, the CAD group had higher lipoprotein (a) [Lp (a)], apolipoprotein B/apolipoprotein A, total cholesterol/high-density lipoprotein cholesterol (HDL-C), triglyceride/HDL-C and LDL-C/HDL-C. According to the AUCs, Lp (a) combined with cIMT (AUC: 0.713, P < 0.001) had the best performance in predicting CAD compared to other lipid parameters. High level of Lp (a) was also associated with multi-vessel CAD (odds ratio: 1.41, 95% confidence interval: 1.02-1.95, P = 0.036).

Conclusion

For patients with highly suspected CAD, Lp (a) better improved the predictive value of CAD rather than most of blood lipid indices, especially in the absence of high levels of LDL-C. Lp (a) also can be used to predict the multi-vessel CAD.

Lipoprotein(a) in Youth and Prediction of Major Cardiovascular Outcomes in Adulthood

BACKGROUND

Elevated lipoprotein(a) [Lp(a)] is a common risk factor for cardiovascular disease outcomes with unknown mechanisms. We examined its potential role in identifying youths who are at increased risk of developing adult atherosclerotic cardiovascular disease (ASCVD).

METHODS

Lp(a) levels measured in youth 9 to 24 years of age were linked to adult ASCVD and carotid intima-media thickness in the YFS (Cardiovascular Risk in Young Finns Study), in which 95 of the original 3596 participants (2.7%) recruited as children have been diagnosed with ASCVD at a median of 47 years of age. Results observed in YFS were replicated with the use of data for White participants from the BHS (Bogalusa Heart Study). In BHS, 587 White individuals had data on youth Lp(a) (measured at 8-17 years of age) and information on adult events, including 15 cases and 572 noncases. Analyses were performed with the use of Cox proportional hazard regression.

RESULTS

In YFS, those who had been exposed to high Lp(a) level in youth [defined as Lp(a) ≥30 mg/dL] had ≈2 times greater risk of developing adult ASCVD compared with nonexposed individuals (hazard ratio, 2.0 [95% CI, 1.4-2.6]). Youth risk factors, including Lp(a), low-density lipoprotein cholesterol, body mass index, and smoking, were all independently associated with higher risk. In BHS, in an age- and sex-adjusted model, White individuals who had been exposed to high Lp(a) had 2.5 times greater risk (95% CI, 0.9-6.8) of developing adult ASCVD compared with nonexposed individuals. When also adjusted for low-density lipoprotein cholesterol and body mass index, the risk associated with high Lp(a) remained unchanged (hazard ratio, 2.4 [95% CI, 0.8-7.3]). In a multivariable model for pooled data, individuals exposed to high Lp(a) had 2.0 times greater risk (95% CI, 1.0-3.7) of developing adult ASCVD compared with nonexposed individuals. No association was detected between youth Lp(a) and adult carotid artery thickness in either cohort or pooled data.

CONCLUSIONS

Elevated Lp(a) level identified in youth is a risk factor for adult atherosclerotic cardiovascular outcomes but not for increased carotid intima-media thickness.

The relationships between thyroid functions of short-term rapid hypothyroidism and blood lipid levels in post-thyroidectomy patients of differentiated thyroid cancer

Objective

To explore the relationship between short-term rapid hypothyroidism and blood lipid levels in patients with differentiated thyroid cancer (DTC).

Methods

Seventy-five DTC patients scheduled to receive radioactive iodine ablation were enrolled. Levels of thyroid hormone and serum lipids were tested at two time points: the euthyroid before thyroidectomy, and the hypothyroid (off thyroxine). Then the collected data were analyzed.

Results

Totally 75 DTC patients enrolled, among them, 5o were female (66.67%) and 25 were male (33. 33%), with an average age of 52.24 ± 1.24 years old. The short-term rapid severe hypothyroidism induced by thyroid hormone withdrawal significantly aggravated dyslipidemia, particularly in patients with dyslipidemia before thyroidectomy (All P < 0.01). However, there was no significant differences between blood lipid levels with different thyroid stimulating hormone (TSH) levels. And our study showed significant negative correlations between free triiodothyronine levels and the changes from euthyjroidism to hypothyroidism in total cholesterol (r=-0.31, P=0.03), triglycerides (r=-0.39, P=0.006), high density lipoprotein-cholesterol (HDL-C) (r=-0.29, P=0.042), and significant positive correlations between free thyroxine and the changes of HDL-C (r=-0.32, P=0.027) were identified in females, however, which were not observed in males.

Conclusion

Short-term rapids severe hypothyroidism caused by thyroid hormone withdrawal can lead to rapid significant changes in blood lipid levels. It is necessary to pay attention to dyslipidemia and its long-term effects after thyroid hormone withdrawal, especially in patients with dyslipidemia before thyroidectomy.

Clinical trial registration

https://clinicaltrials.gov/ct2/show/NCT03006289?term=NCT03006289&draw=2&rank=1, identifier NCT03006289.

Lipoprotein (a) is a risk factor of aortic valve calcification in patients with a risk of atherosclerosis

Aortic valve calcification (AVC), which causes aortic stenosis (AS), is more common in elderly persons. Controlling for conventional risk variables did not, however, reduce the incidence of AS. Thus, residual risk factors of AS should be identified. We enrolled 513 patients who underwent coronary angiography with computed tomography because of suspicion of coronary artery disease (CAD) or ruling out of CAD before aortic valve replacement. Calcium volume was calculated with a commercially available application. Conventional and lipid-related risk factors including serum levels of Lp(a) were evaluated for all patients. Calcium volume and Lp(a) levels were significantly higher in patients who underwent aortic valve replacement than in those who did not. A single regression analysis showed that the calcium volume was positively associated with age and the Lp(a) levels and negatively associated with the estimated glomerular filtration rate. No statistical significance was observed for other risk factors, including oxidized low-density lipoprotein, omega-3 fatty acids levels. The multiple regression analysis revealed that age (P<0.001), female sex (P<0.05), Lp(a) (P<0.01), and hemoglobin A1c (P<0.01) were determinants of the calcium volume. The area under the curve in receiver operating characteristic analysis of Lp(a) for implementation of AVR was 0.65 at an Lp(a) cut-off level of 16 mg/dL. In conclusion, the serum Lp(a) level is a potent risk factor of AVC in patients with high risk of atherosclerosis. J. Med. Invest. 70 : 450-456, August, 2023.

Impact of anti-oestrogen therapy on lipoprotein(a) in postmenopausal women: a systematic review and meta-analysis of double-blind placebo-controlled clinical studies

PURPOSE

The potential mechanisms of endocrine therapy for thrombosis remain currently unclear, and more studies are warranted for further investigation and elucidation. However, high plasma concentration of lipoprotein(a) (Lp(a)) is a recognized prothrombotic factor. The aim of our study was to systematically evaluate the effect of different anti-oestrogen therapy on plasma Lp(a) level in postmenopausal women.

METHODS

A systematic literature search was conducted in multiple electronic databases to identify the randomized, double-blind, placebo-controlled clinical studies on this topic. Effect size for changes in Lp(a) was expressed as mean difference (MD) and 95% confidence intervals (CI).

RESULTS

Data were pooled from 10 clinical trials comprising 24 treatment arms, which included 2049 women (1128 women in the active-treated arms and 921 women in the control arms). Meta-analysis of data suggested that anti-oestrogen therapy in women significantly reduced Lp(a) [MD = -5.92% (95%CI: -9.05%,-2.8%)].

CONCLUSIONS

This observation is of both clinical and pathophysiological relevance, also in view that the identification of molecular determinants and cellular pathways implicated in Lp(a) synthesis and metabolism is still of concern as a critical issue in lipidology and CV prevention.

LPA disruption with AAV-CRISPR potently lowers plasma apo(a) in transgenic mouse model: A proof-of-concept study

Lipoprotein(a) (Lp(a)) represents a unique subclass of circulating lipoprotein particles and consists of an apolipoprotein(a) (apo(a)) molecule covalently bound to apolipoprotein B-100. The metabolism of Lp(a) particles is distinct from that of low-density lipoprotein (LDL) cholesterol, and currently approved lipid-lowering drugs do not provide substantial reductions in Lp(a), a causal risk factor for cardiovascular disease. Somatic genome editing has the potential to be a one-time therapy for individuals with extremely high Lp(a). We generated an LPA transgenic mouse model expressing apo(a) of physiologically relevant size. Adeno-associated virus (AAV) vector delivery of CRISPR-Cas9 was used to disrupt the LPA transgene in the liver. AAV-CRISPR nearly completely eliminated apo(a) from the circulation within a week. We performed genome-wide off-target assays to determine the specificity of CRISPR-Cas9 editing within the context of the human genome. Interestingly, we identified intrachromosomal rearrangements within the LPA cDNA in the transgenic mice as well as in the LPA gene in HEK293T cells, due to the repetitive sequences within LPA itself and neighboring pseudogenes. This proof-of-concept study establishes the feasibility of using CRISPR-Cas9 to disrupt LPA in vivo, and highlights the importance of examining the diverse consequences of CRISPR cutting within repetitive loci and in the genome globally.

Association of KATP variants with CMD and RAP in CAD patients with increased serum lipoprotein(a) levels

CONTEXT

Refractory angina pectoris (RAP) is a specific subtype of coronary artery disease (CAD). Lipoprotein(a) [Lp(a)] and its induced coronary microvascular dysfunction (CMD) play an important role in pathogenesis of RAP, but its metabolism was mostly genetically determined. ATP-sensitive potassium channels (KATP) is involved in lipid metabolism and microvascular homeostasis, and becomes a promising target for the management of Lp(a) and its related RAP.

OBJECTIVE

To investigate associations of KATP variants with hyperlipoprotein(a)emia, CMD and RAP in CAD patients.

DESIGN, PATIENTS, SETTINGS

A total of 1,148 newly diagnosed CAD patients were prospectively selected, and divided into control [Lp(a) < 180 mg/dL] and case [Lp(a) ≥ 180 mg/dL, hyperlipoprotein(a)emia] group.

METHODS

9 KATP variants were genotyped by MassARRAY system. The expression profile of exosome-derived microRNAs (exo-miRs) was identified by next-generation sequencing, and the expression levels of differentially expressed exo-miRs were evaluated by qRT-PCR in verification cohort.

RESULTS

Three KATP variants were associated with increased risk of hyperlipoprotein(a)emia in CAD patients as follows: rs2285676 (AA + GA genotype, adjusted OR = 1.44, 95% CI: 1.10-1.88, P = 0.008), rs1799858 (CC genotype, adjusted OR = 1.33, 95% CI: 1.03-1.73, P = 0.030), and rs141294036 (CC genotype, adjusted OR = 1.43, 95% CI: 1.10-1.87, P = 0.008). Only rs141294036 was associated with increased risk of CMD (CC genotype, adjusted OR = 1.62, 95% CI: 1.23-2.13, P = 0.001), and further with increased RAP risk (CC genotype, adjusted HR = 2.05, 95% CI: 1.22-3.43, P = 0.007) after median follow-up of 50.6-months. Between the two genotypes of rs141294036, 152 exo-miRs were significantly differentially expressed, only 10 exo-miRs (miR-7110-3p, miR-548az-5p, miR-214-3p, let-7i-5p, miR-218-5p, miR-128-3p, miR-378i, miR-625-3p, miR-128-1-5p and miR-3187-3p) were further confirmed in RAP patients with hyperlipoprotein(a)emia and CMD.

CONCLUSION

KATP rs141294036 may serve a potential genetic marker for hyperlipoprotein(a)emia, CMD and RAP in CAD patients.

Inter-Individual Variability in Lipid Response: A Narrative Review

Lipid-lowering guidelines emphasize shared decision-making between clinicians and patients, resulting in patients anticipating the degree of response from diet or drug therapy. Challenging for physicians is understanding the sources of variability complicating their management decisions, which include non-adherence, genetic considerations, additional lipid parameters including lipoprotein (a) levels, and rare systemic responses limiting benefits that result in non-responsiveness to monoclonal antibody injection. In this narrative review, we focus on the variability of low-density lipoprotein cholesterol (LDL-C) response to guideline-directed interventions such as statins, ezetimibe, bile acid sequestrants, fibrates, proprotein/convertase subtilisin-kexin type 9 inhibitors, and LDL-C-lowering diets. We hypothesize that the variability in individual lipid responses is multifactorial. We provide an illustrative model with a check list that can be used to identify factors that may be present in the individual patient.

Obesity Pillars Roundtable: Body mass index and body composition in Black and Female individuals. Race-relevant or racist? Sex-relevant or sexist?

Background

Body mass index (BMI or weight in kilograms/height in meters2) is the most common metric to diagnose overweight and obesity. However, a body composition analysis more thoroughly assesses adiposity, percent body fat, lean body mass (i.e., including skeletal muscle), and sometimes bone mineral density. BMI is not an accurate assessment of body fat in individuals with increased or decreased muscle mass; the diagnostic utility of BMI in individuals is also influenced by race and sex.

Methods

Previous Obesity Pillars Roundtables addressed the diagnostic limitations of BMI, the importance of android and visceral fat (especially among those with South and East Asian ancestry), and considerations of obesity among individuals who identify as Hispanic, diverse in sexual-orientation, Black, Native American, and having ancestry from the Mediterranean and Middle East regions. This roundtable examines considerations of BMI in Black and female individuals.

Results

The panelists agreed that body composition assessment was a more accurate measure of adiposity and muscle mass than BMI. When it came to matters of race and sex, one panelist felt: "race is a social construct and not a defining biology." Another felt that: "BMI should be a screening tool to prompt further evaluation of adiposity that utilizes better diagnostic tools for body composition." Regarding bias and misperceptions of resistance training in female individuals, another panelist stated: "I have spent my entire medical career taking care of women and have never seen a woman unintentionally gain 'too much' muscle mass and bulk up from moderate strength training."

Conclusions

Conveying the importance of race and sex regarding body composition has proven challenging, with the discussion sometimes devolving into misunderstandings or misinformation that may be perceived as racist or sexist. Body composition analysis is the ultimate diagnostic equalizer in addressing the inaccuracies and biases inherent in the exclusive use of BMI.

Markers of Hereditary Thrombophilia with Unclear Significance

Thrombophilia leads to an increased risk of venous thromboembolism. Widely accepted risk factors for thrombophilia comprise deficiencies of protein C, protein S, and antithrombin, as well as the factor V "Leiden" mutation, the prothrombin G20210A mutation, dysfibrinogenemia, and, albeit less conclusive, increased levels of factor VIII. Besides these established markers of thrombophilia, risk factors of unclear significance have been described in the literature. These inherited risk factors include deficiencies or loss-of-activity of the activity of ADAMTS13, heparin cofactor II, plasminogen, tissue factor pathway inhibitor (TFPI), thrombomodulin, protein Z (PZ), as well as PZ-dependent protease inhibitor. On the other hand, thrombophilia has been linked to the gain-of-activity, or elevated levels, of α2-antiplasmin, angiotensin-converting enzyme, coagulation factors IX (FIX) and XI (FXI), fibrinogen, homocysteine, lipoprotein(a), plasminogen activator inhibitor-1 (PAI-1), and thrombin-activatable fibrinolysis inhibitor (TAFI). With respect to the molecular interactions that may influence the thrombotic risk, more complex mechanisms have been described for endothelial protein C receptor (EPCR) and factor XIII (FXIII) Val34Leu. With focus on the risk for venous thrombosis, the present review aims to give an overview on the current knowledge on the significance of the aforementioned markers for thrombophilia screening. According to the current knowledge, there appears to be weak evidence for a potential impact of EPCR, FIX, FXI, FXIII Val34Leu, fibrinogen, homocysteine, PAI-1, PZ, TAFI, and TFPI on the thrombotic risk.

Consensus and guidelines on lipoprotein(a) - seeing the forest through the trees

PURPOSE OF THE REVIEW

Over the past decade, lipoprotein(a) [Lp(a)] made it to several consensus and guideline documents. This review aims to summarize the literature which underlies the various recommendations and compares recent European and North American consensus and guideline documents of the recent 3-4 years.

RECENT FINDINGS

Multiple large epidemiological and genetic studies have provided strong evidence for a causal association between Lp(a) concentrations and atherosclerotic cardiovascular disease (ASCVD) and aortic valve stenosis. There is a dose-dependent linear relationship between Lp(a) and ASCVD risk advocating to consider Lp(a) on a continuous scale rather than using thresholds. The best way to implement this in the clinic is by individualizing the Lp(a)-related risk using tools such as the 'Lp(a) risk calculator' ( http://www.lpaclinicalguidance.com ) that takes into account the Lp(a) level in the context of an individual's traditional risk factors and global risk for ASCVD. There is growing agreement across the guidelines regarding the clinical utility of measuring Lp(a) and more recent expert groups advocate for a general screening approach applied to all adults. As long as the cardiovascular outcomes trials for specific Lp(a)-lowering drugs are in progress, the current management of patients with high Lp(a) should focus on the comprehensive management of all other modifiable ASCVD risk factors which can be therapeutically addressed as per guideline recommendations.

SUMMARY

Since the contribution of high Lp(a) concentrations to global ASCVD risk has been underestimated in the past, a clear recommendation to measure Lp(a) at least once in a person's lifetime is imperative. Recent expert consensus recommendations provide clinicians with direction on how to manage the excess risk associated with elevated Lp(a) concentration by comprehensive and individualized management of modifiable ASCVD risk factors while awaiting the results of clinical trials of Lp(a) targeted therapies.

New Horizons: Revival of Lipoprotein (a) as a Risk Factor for Cardiovascular Disease

The status of lipoprotein (a) [Lp(a)] as a cardiovascular risk factor has been resurrected by advances in genetics. Mendelian randomization studies show a causal link of Lp(a) with coronary artery disease (CAD), peripheral artery disease (PAD), and calcific aortic valve stenosis (CAVS). The genetics of Lp(a) is complex and extends beyond the kringle-IV type 2, as it is also dependent on ancestry. The plasma concentration of Lp(a) is determined by the hepatic production of apolipoprotein(a) [apo(a)] component of Lp(a), supporting the use of nucleic acids that inhibit the messenger RNA (mRNA) gene transcript for apo(a). Analytical barriers to measurement of Lp(a) are being addressed using isoform independent assays and a traceable standard. The association of Lp(a) and atherosclerotic cardiovascular disease is higher for myocardial infarction than PAD and CAVS. Increased risk of type 2 diabetes mellitus associated with low Lp(a) levels is perplexing and requires further investigation. The greatest advancement in Lp(a)-lowering therapies is based on using RNA therapeutics that are now being investigated in clinical trials. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition lowers Lp(a) modestly, but whether cardiovascular benefit is independent of low-density lipoprotein lowering remains unclear. Opportunistic and selective testing for Lp(a) is supported by moderate evidence, with the case for universal screening premature. Modification of behavioral and clinical risk factors may be targeted to mitigate Lp(a)-mediated risk of cardiovascular disease. Clinical practice guidelines have been developed to address gaps in care of high Lp(a), but full implementation awaits the findings of clinical outcome trials using RNA-directed therapies currently underway.

Small Interfering RNA to Reduce Lipoprotein(a) in Cardiovascular Disease

BACKGROUND

Lipoprotein(a) is a presumed risk factor for atherosclerotic cardiovascular disease. Olpasiran is a small interfering RNA that reduces lipoprotein(a) synthesis in the liver.

METHODS

We conducted a randomized, double-blind, placebo-controlled, dose-finding trial involving patients with established atherosclerotic cardiovascular disease and a lipoprotein(a) concentration of more than 150 nmol per liter. Patients were randomly assigned to receive one of four doses of olpasiran (10 mg every 12 weeks, 75 mg every 12 weeks, 225 mg every 12 weeks, or 225 mg every 24 weeks) or matching placebo, administered subcutaneously. The primary end point was the percent change in the lipoprotein(a) concentration from baseline to week 36 (reported as the placebo-adjusted mean percent change). Safety was also assessed.

RESULTS

Among the 281 enrolled patients, the median concentration of lipoprotein(a) at baseline was 260.3 nmol per liter, and the median concentration of low-density lipoprotein cholesterol was 67.5 mg per deciliter. At baseline, 88% of the patients were taking statin therapy, 52% were taking ezetimibe, and 23% were taking a proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitor. At 36 weeks, the lipoprotein(a) concentration had increased by a mean of 3.6% in the placebo group, whereas olpasiran therapy had significantly and substantially reduced the lipoprotein(a) concentration in a dose-dependent manner, resulting in placebo-adjusted mean percent changes of -70.5% with the 10-mg dose, -97.4% with the 75-mg dose, -101.1% with the 225-mg dose administered every 12 weeks, and -100.5% with the 225-mg dose administered every 24 weeks (P&lt;0.001 for all comparisons with baseline). The overall incidence of adverse events was similar across the trial groups. The most common olpasiran-related adverse events were injection-site reactions, primarily pain.

CONCLUSIONS

Olpasiran therapy significantly reduced lipoprotein(a) concentrations in patients with established atherosclerotic cardiovascular disease. Longer and larger trials will be necessary to determine the effect of olpasiran therapy on cardiovascular disease. (Funded by Amgen; OCEAN[a]-DOSE ClinicalTrials.gov number, NCT04270760.).

The relationship between lipoprotein(a) and risk of cardiovascular disease: a Mendelian randomization analysis

BACKGROUND

Lipoprotein(a) [Lp(a)] is one of the residual risk factors for cardiovascular disease (CVD) in the setting of optimal low-density lipoprotein cholesterol (LDL-C). The association between Lp(a) and CVD is still in the exploratory phase, with few studies indicating a causal connection between Lp(a) and various CVD.

METHODS

Lp(a) (n = 377,590) was a genome-wide association study (GWAS) based on European populations from Neale Lab. Large GWAS datasets for CVD, including aortic aneurysm(AA) (n = 209,366), atrial fibrillation(AF) (n = 1,030,836), coronary heart disease(CHD) (n = 361,194), secondary hypertension(HBP) (n = 164,147), heart failure(HF) (n = 208,178), ischemic stroke (IS) (n = 218,792), large artery atherosclerosis stroke(ISL) (n = 150, 765), small vessel stroke(ISS) (n = 198,048), lacunar stroke(LIS) (n = 225,419), and pulmonary embolism(PE) (n = 218,413) were also based on European populations. We performed separate univariate two-sample Mendelian randomization (MR) analysis for Lp(a) and CVD as described above. We evaluated this connection mainly using the random-effects inverse variance weighted technique(IVW1) with a 95% confidence interval (CI) for the odds ratio (OR). This was supplemented by MR-Egger, weighted median, maximum likelihood, penalized weighted median, and fixed-effects inverse variance weighted methods. MR-PRESSO offers another means of statistical detection.

RESULTS

Our two-sample MR, which was predominately based on IVW1, revealed a causal relationship between Lp(a) and AA (OR = 1.005, 95%CI: 1.001-1.010, P = 0.009), CHD (OR = 1.003, 95%CI 1.001-1.004, P = 0.010), and ISL (OR = 1.003, 9 5%CI 1.002-1.004, P = 9.50E-11), in addition, there is no causal association with AF, HBP, HF, IS, ISS, LIS, or PE. Similar conclusions were reached by the MR-PRESSO method.

CONCLUSION

This MR study suggested a causal relationship between Lp(a) and CHD, AA, and ISL, but not associated with AF, HF, IS, LIS, ISS, HBP, or PE. Our work further verifies the association between Lp(a) and various CVD, resulting in improved Lp(a) management and a reduction in the prevalence of CVD.

Lipoprotein(a): Evidence for Role as a Causal Risk Factor in Cardiovascular Disease and Emerging Therapies

Lipoprotein(a) (Lp(a)) is an established risk factor for multiple cardiovascular diseases. Several lines of evidence including mechanistic, epidemiologic, and genetic studies support the role of Lp(a) as a causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and aortic stenosis/calcific aortic valve disease (AS/CAVD). Limited therapies currently exist for the management of risk associated with elevated Lp(a), but several targeted therapies are currently in various stages of clinical development. In this review, we detail evidence supporting Lp(a) as a causal risk factor for ASCVD and AS/CAVD, and discuss approaches to managing Lp(a)-associated risk.

Study design and rationale for the Olpasiran trials of Cardiovascular Events And lipoproteiN(a) reduction-DOSE finding study (OCEAN(a)-DOSE)

BACKGROUND

Data support lipoprotein(a) (Lp[Lp(a)]) being a risk factor for atherosclerotic cardiovascular disease (ASCVD). Olpasiran is a small interfering RNA molecule that markedly reduces Lp(a) production in hepatocytes.

STUDY DESIGN

The Olpasiran trials of Cardiovascular Events And lipoproteiN(a) reduction-DOSE finding study is a multicenter, randomized, double-blind, placebo-controlled dose-finding study in 281 subjects with established ASCVD and Lp(a) > 150 nmol/L. Patients were randomly allocated to one of 4 active subcutaneous doses of olpasiran (10 mg q12 weeks, 75 mg q12 weeks, 225 mg q 12 weeks, or 225 mg q24 weeks) or matched placebo. The primary objective is to evaluate the effects of olpasiran dosed every 12 weeks compared with placebo on the percent change in Lp(a) from baseline at 36 weeks. Enrollment is now complete and follow-up is ongoing.

CONCLUSIONS

OCEAN(a)-DOSE trial is assessing the Lp(a)-lowering efficacy and safety of olpasiran. These data will be used to determine optimal dosing and design for a cardiovascular outcomes trial.

Lipoprotein Assessment in the twenty-first Century

Based on decades of both basic science and epidemiologic research, there is overwhelming evidence for the causal relationship between high levels of cholesterol, especially low-density lipoprotein cholesterol and cardiovascular disease. Risk evaluation and monitoring the response to lipid-lowering therapies are heavily dependent on the accurate assessment of plasma lipoproteins in the clinical laboratory. This article provides an update of lipoprotein metabolism as it relates to atherosclerosis and how diagnostic measures of lipids and lipoproteins can serve as markers of cardiovascular risk, with a focus on recent advances in cardiovascular risk marker testing.

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

This study reviews ancestral differences in the genetics of the LPA gene, risk categories of elevated lipoprotein(a) [Lp(a)] as defined by guidelines, ancestry-specific Lp(a) risk, absolute and proportional risk, predictive value of risk thresholds among different ancestries, and differences between laboratory vs clinical accuracy in Lp(a) assays. For clinical decision-making, the preponderance of evidence suggests that the predictive value of Lp(a) does not vary sufficiently to mandate the use of ancestry-specific risk thresholds. This paper interprets the literature on Lp(a) and ancestral risk to support: 1) clinicians on understanding cardiovascular disease risk in different ancestral groups; 2) trialists for the design of clinical trials to ensure adequate ancestral diversity to support broad conclusions of drug effects; 3) regulators in the evaluation of the design and interpretation of results of Lp(a)-lowering trials with different Lp(a) inclusion thresholds; and 4) clinical laboratories to measure Lp(a) by assays that discriminate risk thresholds appropriately.

Lipoprotein(a) in atherosclerotic cardiovascular disease and aortic stenosis: a European Atherosclerosis Society consensus statement

This 2022 European Atherosclerosis Society lipoprotein(a) [Lp(a)] consensus statement updates evidence for the role of Lp(a) in atherosclerotic cardiovascular disease (ASCVD) and aortic valve stenosis, provides clinical guidance for testing and treating elevated Lp(a) levels, and considers its inclusion in global risk estimation. Epidemiologic and genetic studies involving hundreds of thousands of individuals strongly support a causal and continuous association between Lp(a) concentration and cardiovascular outcomes in different ethnicities; elevated Lp(a) is a risk factor even at very low levels of low-density lipoprotein cholesterol. High Lp(a) is associated with both microcalcification and macrocalcification of the aortic valve. Current findings do not support Lp(a) as a risk factor for venous thrombotic events and impaired fibrinolysis. Very low Lp(a) levels may associate with increased risk of diabetes mellitus meriting further study. Lp(a) has pro-inflammatory and pro-atherosclerotic properties, which may partly relate to the oxidized phospholipids carried by Lp(a). This panel recommends testing Lp(a) concentration at least once in adults; cascade testing has potential value in familial hypercholesterolaemia, or with family or personal history of (very) high Lp(a) or premature ASCVD. Without specific Lp(a)-lowering therapies, early intensive risk factor management is recommended, targeted according to global cardiovascular risk and Lp(a) level. Lipoprotein apheresis is an option for very high Lp(a) with progressive cardiovascular disease despite optimal management of risk factors. In conclusion, this statement reinforces evidence for Lp(a) as a causal risk factor for cardiovascular outcomes. Trials of specific Lp(a)-lowering treatments are critical to confirm clinical benefit for cardiovascular disease and aortic valve stenosis.

Association between lipoprotein(a) and thromboembolism in patients with non-valvular atrial fibrillation: a cross-sectional study

BACKGROUND

Lipoprotein(a) [Lp(a)] is a recognized risk factor for ischemic stroke (IS); however, its role in thromboembolism in patients with non-valvular atrial fibrillation (NVAF) remains controversial. We aimed to assess the association of Lp(a) and IS and systemic embolism (SEE) in NVAF patients.

METHODS

In total, 16,357 patients with NVAF were recruited from the First Affiliated Hospital of Xinjiang Medical University from January 1, 2009, to December 31, 2021, and were divided into groups based on Lp(a) quartiles. Logistic regression models analyzed the association between Lp(a), IS, and SEE. The restriction cubic spline was used to assess the potential nonlinear relationship between Lp(a), IS, and SEE. We conducted subgroup analyses and estimated the multiplicative interaction between the stratified variables and Lp(a) to investigate whether the association between Lp(a) and IS and SEE was affected by age, sex, anticoagulants, and CHA₂DS₂-VASc score.

RESULTS

We identified 1319 IS and 133 SEE events. After correcting for CHA₂DS₂-VASc score and other potential confounders, each 1-standard deviation (SD) increase in log-Lp(a) was related to a 23% increased risk of IS (odds ratios [OR], 1.23; 95% confidence intervals [CI], 1.07-1.41). NVAF patients in the highest Lp(a) quartile were 1.23-fold more likely to have IS than those in the lowest quartile (OR, 1.23; 95% CI, 1.04-1.45). A positive linear relationship between Lp(a) and IS risk was observed (P for nonlinear = 0.341). In the fully adjusted model, subjects had a 1.78-fold increased risk of SEE for each 1-SD increase in log-Lp(a) (OR, 2.78; 95% CI, 1.78-4.36). Subjects in the highest Lp(a) quartile had a 2.38-fold elevated risk of SEE (OR, 3.38; 95% CI, 1.85-6.19) compared with the lowest quartile. Furthermore, Lp(a) had a nonlinear relationship with the risk of SEE (P for nonlinear = 0.005).

CONCLUSIONS

Elevated Lp(a) concentration was significantly associated with IS and SEE, suggesting that Lp(a) may be an emerging biomarker that can help clinicians identify patients at high risk of thromboembolism in this population.

Triglyceride Metabolism Modifies Lipoprotein(a) Plasma Concentration

BACKGROUND

Lipoprotein(a) (Lp(a)) is a significant cardiovascular risk factor. Knowing the mechanisms that regulate its concentration can facilitate the development of Lp(a)-lowering drugs. This study analyzes the relationship between triglycerides (TGs) and Lp(a) concentrations, cross-sectionally and longitudinally, and the influence of the number and composition of TG-rich lipoproteins, and the APOE genotype.

METHODS

Data from Aragon Workers Health Study (AWHS) (n = 5467), National Health and Nutrition Examination Survey III phase 2 (n = 3860), and Hospital Universitario Miguel Servet (HUMS) (n = 2079) were used for cross-sectional TG and Lp(a) relationship. Lp(a) intrasubject variation was studied in AWHS participants and HUMS patients with repeated measurements. TG-rich lipoproteins were quantified by nuclear magnetic resonance in a subsample from AWHS. Apolipoproteins B and E were quantified by Luminex in very low-density lipoprotein (VLDL) isolated by ultracentrifugation, from HUMS samples. APOE genotyping was carried in AWHS and HUMS participants. Regression models adjusted for age and sex were used to study the association.

RESULTS

The 3 studies showed an inverse relationship between TG and Lp(a). Increased VLDL number, size, and TG content were associated with significantly lower Lp(a). There was an inverse association between the apoE concentration in VLDL and Lp(a). No significant association was observed for apolipoprotein (apo)B. Subjects carrying the apoE2/E2 genotype had significantly lower levels of Lp(a).

CONCLUSION

Our results show an inverse relationship Lp(a)-TG. Subjects with larger VLDL size have lower Lp(a), and lower values of Lp(a) were present in patients with apoE-rich VLDL and apoE2/E2 subjects. Our results suggest that bigger VLDLs and VLDLs enriched in apoE are inversely involved in Lp(a) plasma concentration.

Lipoprotein Subfractions as Markers for Predicting the Presence and Severity of Coronary Artery Disease in Patients Undergoing Coronary Angiography

Patients with coronary artery disease (CAD) often have normal blood cholesterol profiles that make it difficult to identify those at risk. The role of lipoprotein subfractions in the development of CAD has attracted increasing attention, and can further stratify risks. We enrolled 1578 patients undergoing coronary angiography and not taking any lipid-lowering drugs; 1033 of them were diagnosed with CAD. The severity of CAD was assessed using Gensini score (GS) and divided into 3 groups. Multivariate regression analysis showed that low-density lipoprotein particle 6 (LDL-P6) and lipoprotein (a) (Lp(a)) were independent risk factors for CAD, apart for the traditional risk factors. In receiver-operating characteristic (ROC) analysis for predicting the presence of CAD, the area under the ROC curve of traditional risk factors combined with Lp(a) and LDL-P6 for predicting CAD was .723, which was better than for traditional risk factors (P = .023). The plasma LDL-P6 and Lp(a) concentrations in the highest tertile GS group were significantly higher than that in the lowest GS group (P < .001). Stepwise linear regression analysis demonstrated positive correlations between Lp(a), LDL-P6 and GS (P = .007 and P < .001). LDL-P6 and Lp(a) are useful markers for predicting the presence and severity of CAD.

New, Novel Lipid-Lowering Agents for Reducing Cardiovascular Risk: Beyond Statins

Statins are the cornerstone of the prevention and treatment of atherosclerotic cardiovascular disease (ASCVD). However, even under optimal statin therapy, a significant residual ASCVD risk remains. Therefore, there has been an unmet clinical need for novel lipid-lowering agents that can target low-density lipoprotein cholesterol (LDL-C) and other atherogenic particles. During the past decade, several drugs have been developed for the treatment of dyslipidemia. Inclisiran, a small interfering RNA that targets proprotein convertase subtilisin/kexin type 9 (PCSK9), shows comparable effects to that of PCSK9 monoclonal antibodies. Bempedoic acid, an ATP citrate lyase inhibitor, is a valuable treatment option for the patients with statin intolerance. Pemafibrate, the first selective peroxisome proliferator-activated receptor alpha modulator, showed a favorable benefit-risk balance in phase 2 trial, but the large clinical phase 3 trial (PROMINENT) was recently stopped for futility based on a late interim analysis. High dose icosapent ethyl, a modified eicosapentaenoic acid preparation, shows cardiovascular benefits. Evinacumab, an angiopoietin-like 3 (ANGPTL3) monoclonal antibody, reduces plasma LDL-C levels in patients with refractory hypercholesterolemia. Novel antisense oligonucleotides targeting apolipoprotein C3 (apoC3), ANGPTL3, and lipoprotein(a) have significantly attenuated the levels of their target molecules with beneficial effects on associated dyslipidemias. Apolipoprotein A1 (apoA1) is considered as a potential treatment to exploit the athero-protective effects of high-density lipoprotein cholesterol (HDL-C), but solid clinical evidence is necessary. In this review, we discuss the mode of action and clinical outcomes of these novel lipid-lowering agents beyond statins.

Lipoprotein(a): Insights for the Practicing Clinician

Following the discovery of the Lipoprotein(a) (Lp(a)) molecule by Kare Berg in 1963, many physiological and pathological properties of this particle remain to be fully understood. Multiple population-based studies have demonstrated a correlation between elevated Lp(a) levels and the incidence of cardiovascular disease. Data extrapolated from the Copenhagen City Heart and ASTRONOMER studies also demonstrated the link between Lp(a) levels and the incidence and rate of progression of calcific aortic stenosis. Interest in Lp(a) has increased in recent years, partly due to new emerging therapies that can specifically reduce serum Lp(a) concentrations. Given the strong correlation between Lp(a) and CV disease from epidemiological studies, several international guidelines have also been updated to advocate Lp(a) testing in specific population groups. This review aims to highlight the importance of the role of Lp(a) in cardiovascular disease and discusses the potential of novel therapies in patients with elevated Lp(a) levels.

Elevated lipoprotein(a) as a predictor for coronary events in older men

Elevated circulating lipoprotein (a) [Lp(a)] is associated with an increased risk of first and recurrent cardiovascular events; however, the effect of baseline Lp(a) levels on long-term outcomes in an elderly population is not well understood. The current single-center prospective study evaluated the association of Lp(a) levels with incident acute coronary syndrome to identify populations at risk of future events. Lp(a) concentration was assessed in 755 individuals (mean age of 71.9 years) within the community and followed for up to 8 years (median time to event, 4.5 years; interquartile range, 2.5–6.5 years). Participants with clinically relevant high levels of Lp(a) (>50 mg/dl) had an increased absolute incidence rate of ASC of 2.00 (95% CI, 1.0041) over 8 years (P = 0.04). Moreover, Kaplan-Meier cumulative event analyses demonstrated the risk of ASC increased when compared with patients with low (<30 mg/dl) and elevated (30–50 mg/dl) levels of Lp(a) over 8 years (Gray’s test; P = 0.16). Within analyses adjusted for age and BMI, the hazard ratio was 2.04 (95% CI, 1.0–4.2; P = 0.05) in the high versus low Lp(a) groups. Overall, this study adds support for recent guidelines recommending a one-time measurement of Lp(a) levels in cardiovascular risk assessment to identify subpopulations at risk and underscores the potential utility of this marker even among older individuals at a time when potent Lp(a)-lowering agents are undergoing evaluation for clinical use.

Ten things to know about ten cardiovascular disease risk factors - 2022

The American Society for Preventive Cardiology (ASPC) "Ten things to know about ten cardiovascular disease risk factors - 2022" is a summary document regarding cardiovascular disease (CVD) risk factors. This 2022 update provides summary tables of ten things to know about 10 CVD risk factors and builds upon the foundation of prior annual versions of "Ten things to know about ten cardiovascular disease risk factors" published since 2020. This 2022 version provides the perspective of ASPC members and includes updated sentinel references (i.e., applicable guidelines and select reviews) for each CVD risk factor section. The ten CVD risk factors include unhealthful dietary intake, physical inactivity, dyslipidemia, pre-diabetes/diabetes, high blood pressure, obesity, considerations of select populations (older age, race/ethnicity, and sex differences), thrombosis (with smoking as a potential contributor to thrombosis), kidney dysfunction and genetics/familial hypercholesterolemia. Other CVD risk factors may be relevant, beyond the CVD risk factors discussed here. However, it is the intent of the ASPC "Ten things to know about ten cardiovascular disease risk factors - 2022" to provide a tabular overview of things to know about ten of the most common CVD risk factors applicable to preventive cardiology and provide ready access to applicable guidelines and sentinel reviews.

Non-genetic influences on lipoprotein(a) concentrations

An elevated level of lipoprotein(a) [Lp(a)] is a genetically regulated, independent, causal risk factor for cardiovascular disease. However, the extensive variability in Lp(a) levels between individuals and population groups cannot be fully explained by genetic factors, emphasizing a potential role for non-genetic factors. In this review, we provide an overview of current evidence on non-genetic factors influencing Lp(a) levels with a particular focus on diet, physical activity, hormones and certain pathological conditions. Findings from randomized controlled clinical trials show that diets lower in saturated fats modestly influence Lp(a) levels and often in the opposing direction to LDL cholesterol. Results from studies on physical activity/exercise have been inconsistent, ranging from no to minimal or moderate change in Lp(a) levels, potentially modulated by age and the type, intensity, and duration of exercise modality. Hormone replacement therapy (HRT) in postmenopausal women lowers Lp(a) levels with oral being more effective than transdermal estradiol; the type of HRT, dose of estrogen and addition of progestogen do not modify the Lp(a)-lowering effect of HRT. Kidney diseases result in marked elevations in Lp(a) levels, albeit dependent on disease stages, dialysis modalities and apolipoprotein(a) phenotypes. In contrast, Lp(a) levels are reduced in liver diseases in parallel with the disease progression, although population studies have yielded conflicting results on the associations between Lp(a) levels and nonalcoholic fatty liver disease. Overall, current evidence supports a role for diet, hormones and related conditions, and liver and kidney diseases in modifying Lp(a) levels.

Lipoprotein(a) and cardiovascular and valvular diseases: A genetic epidemiological perspective

Rates of atherosclerotic cardiovascular diseases (CVD) in the Western world have spectacularly decreased over the past 50 years. However, a substantial proportion of high-risk patients still develop heart attacks, strokes and valvular heart diseases despite benefiting from state-of-the-art treatments including lipid-lowering therapies. Over the past 10-15 years, it has become increasingly clear that Lipoprotein(a) (Lp[a]) is a critical component of this so-called residual risk. Genetic association studies revealed that Lp(a) is robustly, independently and causally associated with a broad range of cardiovascular and valvular heart diseases. Up to 1 billion people around the globe may have an Lp(a) level that places them in a high-risk category. Lp(a) is strongly associated with calcific aortic valve stenosis (CAVS), coronary artery disease (CAD), peripheral arterial disease (PAD) and to a lesser extent with ischemic stroke (IS) and heart failure (HF). Because of this strong association with cardiovascular and valvular heart diseases, Lp(a) even emerged as one of the most important genetic determinants of human lifespan and healthspan. Here, we review the evidence from the largest and most informative genetic association studies and prospective studies that have investigated the association between Lp(a) and human lifespan, healthspan, CVD, CAVS and non-cardiovascular diseases. We present Lp(a) threshold values that may be clinically relevant and identify other cardiovascular risk factors that may modulate the absolute risk of CVD in individuals with high Lp(a) levels. Finally, we identify key clinical and research questions that require further investigation to eventually and optimally reduce CVD risk in patients with high Lp(a) levels.

Lipoprotein(a) and Cardiovascular Outcomes in Patients With Coronary Artery Disease and Different Metabolic Phenotypes

Background

The positive relationship between metabolic healthy obesity (MHO) and cardiovascular risk has been under debate in recent years. Previously, strong evidence supported the causal role of increased plasma lipoprotein(a) [Lp(a)] levels in cardiovascular disease (CVD). The current study aimed to investigate the different associations of Lp(a) and cardiovascular events (CVEs) in patients with coronary artery disease (CAD) and different metabolic phenotypes.

Methods

A total of 5,089 patients who were angiography-proven CAD were consecutively included and followed up for CVEs. Obesity was defined as a body mass index (BMI) ≥25 kg/m² according to Asia-specific BMI criteria. Patients were divided into four groups according to metabolic phenotypes, namely metabolically healthy/unhealthy non-obese and metabolically healthy/unhealthy obese [metabolically healthy non-obese (MHN), MHO, metabolically unhealthy non-obese (MUN), and metabolically unhealthy obesity (MUO)]. Comparisons of CAD severity and outcomes were performed among four groups. Cox regression analyses and cubic spline models were used to examine the relationship between Lp(a) and CVEs in patients with different metabolic phenotypes.

Results

During a median of 7.5 years’ follow-up, 540 (10.6%) CVEs occurred. MUN and MUO populations had more severe coronary stenosis than MHN ones, while no significant difference in the Gensini score (GS) was observed between MHN and MHO. Patients with MUN and MUO presented a higher risk of CVEs than patients with MHN (hazard ratio [HR]: 1.414, 95% CI: 1.024–1.953–1.556 and HR: 1.747, 95% CI: 1.295–1.363, p < 0.05). In subgroup analysis, restricted cubic spline models showed that there was no association between Lp(a) and CVEs in patients in MHN and MHO, while the MUN and MUO groups presented increasing associations between Lp(a) and CVEs and such association was stronger in the MUO group. In Cox regression analysis, Lp(a) >50 mg/dl was associated with a 2.032- and 2.206-fold higher risk of subsequent CVEs in the MUO and MUN subgroups, respectively.

Conclusion

Among patients with angiography-proven stable CAD, Lp(a) had a more significant prognostic value in both MUO and MUN individuals regardless of obesity, suggesting the importance of screening for cardiovascular risk with Lp(a) in metabolically unhealthy patients.

Familial Hypercholesterolemia and Elevated Lipoprotein(a): Cascade Testing and Other Implications for Contextual Models of Care

Elevated lipoprotein(a) [Lp(a)], a predominantly genetic disorder, is a causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valvular disease, particularly in patients with familial hypercholesterolemia (FH), a Tier I genomic condition. The combination from birth of the cumulative exposure to elevated plasma concentrations of both Lp(a) and low-density lipoprotein is particularly detrimental and explains the enhanced morbidity and mortality risk observed in patients with both conditions. An excellent opportunity to identify at-risk patients with hyper-Lp(a) at increased risk of ASCVD is to test for hyper-Lp(a) during cascade testing for FH. With probands having FH and hyper-Lp(a), the yield of detection of hyper-Lp(a) is 1 individual for every 2.1-2.4 relatives tested, whereas the yield of detection of both conditions is 1 individual for every 3-3.4 relatives tested. In this article, we discuss the incorporation of assessment of Lp(a) in the cascade testing in FH as a feasible and crucial part of models of care for FH. We also propose a simple management tool to help physicians identify and manage elevated Lp(a) in FH, with implications for the care of Lp(a) beyond FH, noting that the clinical use of RNA therapeutics for specifically targeting the overproduction of Lp(a) in at risk patients is still under investigation.

Moderately elevated lipoprotein (a) levels are associated with an earlier need for percutaneous coronary intervention in recurrent cardiovascular disease

A significant number of cardiovascular disease (CVD) patients, with the target lipid levels, as set by the guidelines, achieved, continue to remain at risk. In this setting, lipoprotein (Lp) a role in CVD prognosis is regaining interest. Although Lp(a) is related to the arteriosclerotic process, there is not currently an adequate amount of data for the inclusion of Lp(a) levels as a primary therapeutic target in the treatment of coronary artery disease (CAD) patients. In this framework, the current retrospective study aims to investigate the association of Lp(a) levels with the adverse cardiovascular (CV) events presented in a 10 year follow-up of CVD patients with dyslipidemia and its association with the major CV risk factors. A statistically significant reduction in Lp(a) levels was observed during the follow-up period (72.8±45.6 vs. 68.3±41.8 mg/dl; McNemar test; P<0.001). The vast majority of patients who suffered a new acute myocardial infarction during the follow up period had Lp(a) levels >30 mg/dl (24/28 patients, mean ± standard deviation Lp(a), 83.1±36.6 mg/dl, P=0.001). Kaplan-Meier survival analysis did not find statistically significant differences in a percutaneous coronary intervention (PCI) time occurrence during the follow-up period between patients with low (≤30 mg/dl) and high (>30 mg/dl) Lp(a) levels (log-rank P=0.305). On the other hand, when a second and third PCI conducted during the monitoring period were included in the Kaplan Meier analysis as events, the mean time for a PCI was significantly shorter (7.2%; P=0.01) for patients with Lp(a) levels >30 mg/dl. In conclusion, the current study reported that patients with high Lp(a) values are more prone to the occurrence of new myocardial infarction, while the Lp(a) cut-off value of 30 mg/dl was linked in CVD patients to an earlier need for PCI, especially in the most vulnerable group of patients with more than one (recurrent) revascularizations.

Association between lipoprotein(a) concentrations and atherosclerotic cardiovascular disease risk in patients with familial hypercholesterolemia: an analysis from the HELLAS-FH

AIMS

Lipoprotein(a) [Lp(a)] is an independent risk factor for atherosclerotic cardiovascular disease (ASCVD) in the general population. However, such a role in patients with familial hypercholesterolemia (FH) is less documented. The purpose of this study was to evaluate the association between Lp(a) concentrations and ASCVD prevalence in adult patients with FH.

METHODS

This was a cross-sectional study from the Hellenic Familial Hypercholesterolemia Registry (HELLAS-FH). Patients were categorized into 3 tertiles according to Lp(a) levels.

RESULTS

A total of 541 adult patients (249 males) with possible/probable/definite FH heterozygous FH (HeFH) were included (mean age 48.5 ± 15.0 years at registration, 40.8 ± 15.9 years at diagnosis). Median (interquartile range) Lp(a) concentrations in the 1st, 2nd and 3rd Lp(a) tertile were 6.4 (3.0-9.7), 22.4 (16.0-29.1) and 77.0 (55.0-102.0) mg/dL, respectively. There was no difference in lipid profile across Lp(a) tertiles. The overall prevalence of ASCVD was 9.4% in the first, 16.1% in the second and 20.6% in the third tertile (p = 0.012 among tertiles). This was also the case for premature ASCVD, with prevalence rates of 8.5, 13.4 and 19.8%, respectively (p = 0.010 among tertiles). A trend for increasing prevalence of coronary artery disease (8.3, 12.2 and 16.1%, respectively; p = 0.076 among tertiles) was also observed. No difference in the prevalence of stroke and peripheral artery disease was found across tertiles.

CONCLUSIONS

Elevated Lp(a) concentrations are significantly associated with increased prevalence of ASCVD in patients with possible/probable/definite HeFH.

Elevated lipoprotein (a) levels and risk of peripheral artery disease outcomes: A systematic review

BACKGROUND

Despite strong association of elevated lipoprotein (a) (Lp(a)) levels with incident coronary and cerebrovascular disease, data for incident peripheral artery disease (PAD) are less robust. The main objective of the present systematic review was to analyze the association between elevated Lp(a) levels and PAD outcomes.

METHODS

This systematic review was performed according to PRISMA guidelines. A literature search was performed to detect randomized clinical trials or observational studies with a cohort design that evaluated the association between Lp(a) levels and PAD outcomes.

RESULTS

Fifteen studies including 493,650 subjects were identified and considered eligible for this systematic review. This systematic review showed that the vast majority of the studies reported a significant association between elevated Lp(a) levels and the risk of PAD outcomes. The elevated Lp(a) levels were associated with a higher risk of incident claudication (RR: 1.20), PAD progression (HR: 1.41), restenosis (HR: 6.10), death and hospitalization related to PAD (HR: 1.37), limb amputation (HR: 22.75), and lower limb revascularization (HR: 1.29 and 2.90). In addition, the presence of elevated Lp(a) values were associated with a higher risk of combined PAD outcomes, with HRs in a range between 1.14 and 2.80, despite adjusting for traditional risk factors. Heterogeneity of results can be explained by different patient populations studied and varying Lp(a) cut-off points of Lp(a) analyzed.

CONCLUSION

This systematic review suggests that evidence is available to support an independent positive association between Lp(a) levels and the risk of future PAD outcomes. PROSPERO Registration No.: 289253.

Cascade testing for elevated lipoprotein(a) in relatives of probands with high lipoprotein(a)

•

Elevated lipoprotein(a) [Lp(a)] is a common inherited condition associated with atherosclerotic cardiovascular disease.

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Elevated Lp(a) is not routinely tested in clinical practice and most cases remain undiagnosed in the community.

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We identified 124 relatives with elevated Lp(a) (≥50 mg/dL) from 83 affected adult probands who also had dyslipidemia.

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We also demonstrate that follow-up management is effective in lowering low-density lipoprotein-cholesterol levels by 34% as a consequence of initiation of lipid-lowering therapy.

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Cascade testing families for elevated Lp(a) from affected probands with dyslipidemia is an effective and acceptable approach for identifying new cases of elevated Lp(a) who will require management of modifiable risk factors, particularly hypercholesterolemia.

Objective

Elevated lipoprotein(a) [Lp(a)] is a common inherited condition associated with cardiovascular disease. This study investigated whether cascade testing for Lp(a) was effective in detecting new cases of elevated Lp(a) in families.

Methods

Relatives from adult probands with Lp(a) concentration ≥100 mg/dL were tested for elevated Lp(a) (≥50 mg/dL) via a cascade testing program in a tertiary hospital setting. The prevalence and yield of detecting new cases of elevated Lp(a) among the relatives were assessed.

Results

Of the 83 probands, 43.4% had familial combined hyperlipidemia (FCHL) and 34.9% common hypercholesterolemia (CH). Among 182 relatives tested (151 adults and 31 children), elevated Lp(a) was found in 68.1%, with 32.9% having Lp(a) between 50 and 99 mg/dL and 35.2% having Lp(a) ≥100 mg/dL. One new case of elevated Lp(a) ≥50 mg/dL was identified for every 1.5 relatives tested and 1 new case of elevated Lp(a) ≥100 mg/dL for every 2.8 relatives tested. The proportion of relatives detected with elevated Lp(a) was significantly higher when tested from probands with Lp(a) >150 mg/dL compared with those with Lp(a) between 100 and 150 mg/dL (81.1% vs. 55.5%; P = 0.001). The concordance rates (kappa coefficient) for the detection of elevated Lp(a) with FCHL and CH were 34.8% (0.026) and 53.2% (0.099), respectively.

Conclusion

Cascade testing for elevated Lp(a) from affected probands with phenotypic dyslipidemia is highly effective in identifying new cases of high Lp(a) in families. The yield of detecting elevated Lp(a) is greater when probands have higher levels of Lp(a) and exceeds the detection of relatives with FCHL and CH.

Lipoprotein profiles of fat distribution and its association with insulin sensitivity

BACKGROUND

Fat deposition is associated with adverse outcomes. Waist-to-hip (WHR) ratio is a simple feasible index to assess fat distribution. Lipoprotein particle composition in relation to WHR and to what extent their association is mediated by insulin sensitivity are less investigated.

METHODS

In 504 randomly recruited Flemish (mean age: 48.9 years; women: 51.6%), we analyzed the lipoprotein particle constitutions using nuclear magnetic resonance spectroscopy. WHR obesity described a WHR of ≥ 0.85 for women or 0.9 for men. Insulin sensitivity was evaluated by the homeostasis model assessment-estimated insulin resistance (HOMA-IR). SCORE-2 risk algorithm was applied to estimate 10-year cardiovascular risk. Statistical methods included multivariable-adjusted linear regression analysis, logistic regression analysis, and mediation analysis.

RESULTS

The prevalence of WHR obesity was 54.6%, approximately 3 times of BMI-determined obesity (19.1%). Individuals with WHR obesity had significantly higher metabolic complications, such as hypertension (57.1%), dyslipidemia (61.8%), and insulin resistance (14.2%). WHR and WHR obesity were positively associated with total very-low-density lipoprotein (VLDL) particle concentration, remnant cholesterol, and triglycerides, but were negatively associated with VLDL particle size (P ≤ 0.027), independent of body mass index and other covariates. WHR was inversely associated with total high-density lipoprotein (HDL) particle concentration, whereas WHR obesity was inversely associated with HDL cholesterol (P ≤ 0.039). Neither WHR nor WHR obesity was associated with the concentration of total low-density lipoprotein (LDL) particles, LDL particle size, and LDL cholesterol (P ≥ 0.089). In the mediation analysis, insulin sensitivity significantly mediated the effect of WHR on total VLDL particle concentration (mediation percentage: 37.0%), remnant cholesterol (47.7%), and HDL cholesterol (41.1%). Individuals with WHR obesity were at increased cardiovascular risk, regardless of LDL cholesterol (P ≤0.028). In WHR obesity, higher total VLDL particle concent36ration and remnant cholesterol, and lower HDL cholesterol were associated with an increased cardiovascular risk (P≤ 0.002).

CONCLUSIONS

Upper-body fat deposition was independently associated with an unfavorable lipoprotein profile, and insulin sensitivity significantly mediated this association. LDL cholesterol might underestimate lipid abnormality for people with upper-body obesity and lowering VLDL particles and remnant cholesterol might potentially reduce the residual cardiovascular risk.

Trends in testing and prevalence of elevated Lp(a) among patients with aortic valve stenosis

Background and aims:

Lipoprotein(a) [Lp(a)] is causally associated with aortic valve stenosis (AS) but Lp(a) testing among AS patients is not broadly incorporated into clinical practice. We evaluated trends in Lp(a) testing in an academic medical center.

Methods:

Educational efforts and adding Lp(a) to the lipid panel on the electronic medical record (EMR) and preprocedure order sets were used to increase awareness of Lp(a) as a risk factor in AS. Medical records at University of California San Diego Health (UCSDH) were analyzed from 2010 to 2020 to define the yearly frequency of first time Lp(a) testing in patients with diagnosis codes for AS or undergoing transcatheter aortic valve replacement (TAVR).

Results:

Lp(a) testing for any indication increased over 5-fold from 2010 to 2020. A total of 3808 patients had a diagnosis of AS and 417 patients had TAVR. Lp(a) levels >30 mg/dL were present in 37% of AS and 35% of TAVR patients. The rates of Lp(a) testing in AS and TAVR were 14.0% and 65.7%, respectively. In AS, Lp(a) testing increased over time from 8.5% in 2010, peaking at 24.2% in 2017, and declining to 13.9% in 2020 (p < 0.001 for trend). Following implementation of EMR order-sets in 2016, Lp(a) testing in TAVR cases increased to a peak of 88.5% in 2018.

Conclusions:

Elevated Lp(a) is prevalent in AS and TAVR patients. Implementation of educational efforts and practice pathways resulted in increased Lp(a) testing in patients with AS. This study represents a paradigm that may allow increased global awareness of Lp(a) as a risk factor for AS.