Evaluation of Lipoprotein(a) Electrophoretic and Immunoassay Methods in Discriminating Risk of Calcific Aortic Valve Disease and Incident Coronary Heart Disease: The Multi-Ethnic Study of Atherosclerosis

Lipoprotein(a) and calcific aortic valve disease initiation and progression: a systematic review and meta-analysis

Although evidence indicates the association of lipoprotein(a) [Lp(a)] with atherosclerosis, the link with calcific aortic valve disease (CAVD) is unclear. This systematic review and meta-analysis explores the connection between Lp(a) and aortic valve calcification and stenosis (AVS). We included all relevant studies, indexed in eight databases, up to February 2023. A total of 44 studies (163 139 subjects) were included, with 16 of them being further meta-analysed. Despite considerable heterogeneity, most studies support the relationship between Lp(a) and CAVD, especially in younger populations, with evidence of early aortic valve micro-calcification in elevated-Lp(a) populations. The quantitative synthesis showed higher Lp(a) levels, by 22.63 nmol/L (95% CI: 9.98-35.27), for patients with AVS, while meta-regressing the data revealed smaller Lp(a) differences for older populations with a higher proportion of females. The meta-analysis of eight studies providing genetic data, revealed that the minor alleles of both rs10455872 and rs3798220 LPA gene loci were associated with higher risk for AVS (pooled odds ratio 1.42; 95% CI: 1.34-1.50 and 1.27; 95% CI: 1.09-1.48, respectively). Importantly, high-Lp(a) individuals displayed not only faster AVS progression, by a mean difference of 0.09 m/s/year (95% CI: 0.09-0.09), but also a higher risk of serious adverse outcomes, including death (pooled hazard ratio 1.39; 95% CI: 1.01-1.90). These summary findings highlight the effect of Lp(a) on CAVD initiation, progression and outcomes, and support the early onset of Lp(a)-related subclinical lesions before clinical evidence.

Elevated lipoprotein(a) in mitral and aortic valve calcification and disease: The Copenhagen General Population Study

BACKGROUND AND AIMS

We tested the hypotheses (i) that elevated lipoprotein(a) is causally associated with both mitral and aortic valve calcification and disease, and (ii) that aortic valve calcification mediates the effect of elevated lipoprotein(a) on aortic valve stenosis.

METHODS

From the Copenhagen General Population study, we included 12,006 individuals who underwent cardiac computed tomography to measure mitral and aortic valve calcification and 85,884 to examine risk of heart valve disease. Participants had information on plasma lipoprotein(a) and genetic instruments associated with plasma lipoprotein(a) to investigate potential causality.

RESULTS

At age 70-79 years, 29% and 54% had mitral and aortic valve calcification, respectively. For 10-fold higher lipoprotein(a) levels, multifactorially adjusted odds ratios for mitral and aortic valve calcification were 1.26 (95% confidence interval: 1.13-1.41) and 1.62 (1.48-1.77). For mitral and aortic valve stenosis, corresponding hazard ratios were 0.93 (95%CI:0.40-2.15, 19 events) and 1.54 (1.38-1.71, 1158 events), respectively. For ≤23 versus ≥36 kringle IV type 2 number of repeats, the age and sex adjusted odds ratios for mitral and aortic valve calcification were 1.53 (1.18-1.99) and 2.23 (1.81-2.76). For carriers versus non-carriers of LPA rs10455872, odds ratios for mitral and aortic valve calcification were 1.33 (1.13-1.57) and 1.86 (1.64-2.13). For aortic valve stenosis, 31% (95%CI:16%-76%) of the effect of lipoprotein(a) was mediated through calcification.

CONCLUSIONS

Elevated lipoprotein(a) was genetically and observationally associated with mitral and aortic valve calcification and aortic valve stenosis. Aortic valve calcification mediated 31% of the effect of elevated lipoprotein(a) on aortic valve stenosis.

Association between lipoprotein (a) and heart failure with reduced ejection fraction development

Background

The current study aimed to evaluate the relationship between baseline serum lipoprotein (a) [Lp(a)] level and heart failure with reduced ejection fraction (HFrEF) development.

Methods

This was a retrospective study, and participants were enrolled from the outpatient clinic. All data were extracted from the electronic health record of the outpatient clinic system. The follow‐up was performed through reviewing the clinical notes at the outpatient clinic system, and study outcome of the current study was the first diagnosis of HFrEF. Participants were divided into low Lp(a) (<30 mg/dl, n = 336) and high Lp(a) (≥30 mg/dl, n = 584) groups.

Results

Individuals in the high Lp(a) group were more likely to be men and have diabetes mellitus (DM) and dyslipidemia. Increased Lp(a) at baseline was positively associated with serum N‐terminal pro‐B natriuretic peptide level while negatively associated with left ventricular ejection fraction (LVEF) at follow‐up. After adjusting for covariates, per 10 mg/dl increase in baseline Lp(a) remained significantly associated with HFrEF, with odds ratio of 1.17 (95% confidence interval of 1.05, 1.46). The magnitude of association between baseline Lp(a) level and HFrEF was greater in men and in individuals with DM or coronary heart disease (CHD), while it was weaker in individuals treated with beta‐blocker at baseline.

Conclusion

Increased Lp(a) at baseline was associated with HFrEF development. The adverse effects of Lp(a) were greater on men and individuals with DM or CHD, which were mitigated by beta‐blocker therapy. These findings together underscore the possibility and usefulness of Lp(a) as a new risk factor to predict HFrEF.

PoLA/CFPiP/PCS/PSLD/PSD/PSH guidelines on diagnosis and therapy of lipid disorders in Poland 2021

In Poland there are still nearly 20 million individuals with hypercholesterolaemia, most of them are unaware of their condition; that is also why only ca. 5% of patients with familial hypercholesterolaemia have been diagnosed; that is why other rare cholesterol metabolism disorders are so rarely diagnosed in Poland. Let us hope that these guidelines, being an effect of work of experts representing 6 main scientific societies, as well as the network of PoLA lipid centers being a part of the EAS lipid centers, certification of lipidologists by PoLA, or the growing number of centers for rare diseases, with a network planned by the Ministry of Health, improvements in coordinated care for patients after myocardial infarction (KOS-Zawał), reimbursement of innovative agents, as well as introduction in Poland of an effective primary prevention program, will make improvement in relation to these unmet needs in diagnostics and treatment of lipid disorders possible.

Performance of novel low-density lipoprotein-cholesterol calculation methods in predicting clinical and subclinical atherosclerotic cardiovascular disease risk: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND AND AIMS

This study examined the performance of two novel low-density lipoprotein-cholesterol (LDL-C) calculations, LDL_Martin and LDL_Sampson, on predicting atherosclerotic cardiovascular diseases (ASCVD) risk compared to traditional LDL_Friedewald according to the 2018 American Heart Association/American College of Cardiology (AHA/ACC) primary prevention guidelines.

METHODS

A total of 6701 randomly recruited Multi-Ethnic Study of Atherosclerosis (MESA) participants free of ASCVD at baseline were followed for ASCVD during a median of 13.9 years and for subclinical ASCVD-coronary artery calcium (CAC) during a median of 12.5 years. Prevalence of borderline high triglyceride (≥1.7 mmol/L) was 15.2% and was at 13.5% for high triglyceride (≥2.3 mmol/L).

RESULTS

Applying the criteria of LDL-C<1.8 mmol/L in 40-75 year olds without diabetes mellitus to be exempt from risk discussion, LDL_Martin and LDL_Sampson classified less individuals in this category than LDL_Friedewald (p < 0.001), both had 20 individuals with ASCVD, versus 22 by LDL_Friedewald. Positive CAC in the discussion-exempt group were over 38% higher (p < 0.001) when classified by LDL_Friedewald than by LDL_Martin or LDL_Sampson. Individuals with LDL-C≥4.9 mmol/L are recommended to high-intensity statin therapy by the AHA/ACC guidelines. The LDL_Friedewald≥4.9 mmol/L group had 20 ASCVD events, versus 21 in LDL_Martin and 22 in LDL_Sampson group.

CONCLUSIONS

In a multi-ethnic USA population, LDL_Martin and LDL_Sampson did not over- or under-estimate ASCVD risk compared to LDL_Friedewald in primary prevention according to AHA/ACC guidelines, while LDL_Friedewald under-estimated subclinical ASCVD risk in the low-risk population. These findings support the replacement of LDL_Friedewald by LDL_Martin or LDL_Sampson for lipid screen in the general population.

Lipoprotein (a) and coronary artery calcification: prospective study assessing interactions with other risk factors

BACKGROUND

Elevated plasma lipoprotein (a) [Lp(a)] and coronary artery calcification (CAC) are established cardiovascular risk factors that correlate with each other. We hypothesized that other cardiovascular risk factors could affect their relationship.

METHODS

We tested for interactions of 24 study variables related to dyslipidemia, diabetes, insulin resistance, hypertension, inflammation and coagulation with baseline Lp(a) on change in CAC volume and density over 9.5 years in 5975 Multi-Ethnic Study of Atherosclerosis (MESA) participants, free of apparent cardiovascular disease at baseline.

RESULTS

Elevated Lp(a) was associated with larger absolute increase in CAC volume (3.21 and 4.45 mm3/year higher for Lp(a) ≥30 versus <30 mg/dL, and Lp(a) ≥50 versus <50 mg/dL, respectively), but not relative change in CAC volume. No association was found with change in CAC density when assessing continuous ln-transformed Lp(a). The association between elevated Lp(a) (≥30 mg/dL) and absolute change in CAC volume was greater in participants with higher circulating levels of interleukin-2 soluble receptor α, soluble tumor necrosis factor alpha receptor 1 and fibrinogen (15.33, 11.81 and 7.02 mm3/year in quartile 4, compared to -3.44, -0.59 and 1.91 mm3/year in quartile 1, respectively). No significant interaction was found for other study variables. Similar interactions were seen when assessing Lp(a) levels ≥50 mg/dL.

CONCLUSIONS

Elevated Lp(a) was associated with an absolute increase in CAC volume, especially in participants with higher levels of selected markers of inflammation and coagulation. These results suggest Lp(a) as a potential biomarker for CAC volume progression.

Study of lipoprotein(a) and its impact on atherosclerotic cardiovascular disease: Design and rationale of the Mass General Brigham Lp(a) Registry

Lipoprotein(a) [Lp(a)] is independently associated with atherosclerotic cardiovascular disease and calcific aortic valve stenosis. Elevated Lp(a) affects approximately one in five individuals and meaningfully contributes to the residual cardiovascular risk in individuals with otherwise well-controlled risk factors. With targeted therapies in the therapeutic pipeline, there is a need to further characterize the clinical phenotypes and outcomes of individuals with elevated levels of this unique biomarker. The Mass General Brigham Lp(a) Registry will be built from the longitudinal electronic health record of two large academic medical centers in Boston, Massachusetts, to develop a detailed cohort of patients who have had their Lp(a) measured. In combination with structured data sources, clinical documentation will be analyzed using natural language processing techniques to accurately characterize baseline characteristics. Important outcome measures including all-cause mortality, cardiovascular mortality, and cardiovascular events will be available for analysis. Approximately 30 000 patients who have had their Lp(a) tested within the Mass General Brigham system from January 2000 to July 2019 will be included in the registry. This large Lp(a) cohort will provide meaningful observational data regarding the differential risk associated with Lp(a) values and cardiovascular disease. With a new frontier of targeted Lp(a) therapies on the horizon, the Mass General Brigham Lp(a) Registry will help provide a deeper understanding of Lp(a)'s role in long term cardiovascular outcomes.

Current and future role of lipoprotein(a) in preventive cardiology

PURPOSE OF REVIEW

The purpose of this review is to highlight our emerging understanding of lipoprotein(a) [Lp(a)]'s role in atherosclerotic cardiovascular disease (ASCVD), its structure-function relationship, and promising developments within the therapeutic pipeline.

RECENT FINDINGS

Elevated levels of Lp(a) are strongly associated with an increased risk of coronary heart disease, calcific aortic valve stenosis, and ischemic stroke. With circulating levels almost exclusively genetically mediated, increased levels of Lp(a) contribute significantly to the residual cardiovascular disease risk in individuals with otherwise well controlled risk factors. The unique structure of Lp(a) - comprised of a genetically heterogeneous apolipoprotein(a) molecule bound to an LDL-like moiety - provides insight into its pathogenic role in cardiovascular disease and also complicates its accurate measurement. Emerging therapies targeting the apolipoprotein(a) component of Lp(a) have the potential to revolutionize the management of individuals with elevated Lp(a).

SUMMARY

With promising therapies on the horizon, there has been a renewed focus on the role of Lp(a) in ASCVD. Given Lp(a)'s strong and independent association with key cardiovascular outcomes, it is hopeful that these promising targeted therapies will add another therapeutic option for the prevention of cardiovascular disease.

Lipids: a personal view of the past decade

The past decade has witnessed considerable progress in the field of lipids. New drugs have been "rapidly" developed and some of these drugs have already been evaluated in event-based large trials. This evidence has led to the guidelines recommending new, more aggressive treatment goals for low-density lipoprotein cholesterol (LDL-C) levels. Although LDL-C remains the principal goal for cardiovascular disease (CVD) risk reduction, there has also been considerable interest in other lipid variables, such as high-density lipoprotein cholesterol, triglycerides, and lipoprotein(a). Statin intolerance is now considered a very important topic in daily clinical practice. This has resulted in more attention focusing on non-statin drugs [e.g., ezetimibe and proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitors] and statin-related side effects. The latter mainly involve muscles, but there is also a need to consider other adverse effects associated with statin use (e.g., new onset diabetes). New specific areas of statin use have attracted interest. For example, statin-loading before procedures (e.g., coronary stenting), the prevention of stroke, and the treatment of non-alcoholic fatty liver disease (NAFLD). Statins will remain the most widely used drugs to treat dyslipidaemia and decrease CVD risk. However, we also need to briefly consider some other lipid-lowering drugs, including those that may become available in the future.

Lp(a) [Lipoprotein(a)]-Related Risk of Heart Failure Is Evident in Whites but Not in Other Racial/Ethnic Groups

Objective- Lp(a) [lipoprotein(a)] levels vary by race/ethnicity and were recently found to be associated with risk of heart failure (HF). We aimed to determine whether Lp(a)-related risk of HF is similar across different races and whether Lp(a) may further be related to HF with reduced ejection fraction or HF with preserved ejection fraction (HFpEF). Approach and Results- In 6809 participants of the MESA (Multi-Ethnic Study of Atherosclerosis), aged 45 to 84 years and free of cardiovascular disease, 308 incident HF events occurred during a median 13-year follow-up. Baseline Lp(a) concentrations were determined by immunoassay. Incident HF was adjudicated, distinguishing HF with reduced ejection fraction (ejection fraction, <45%) from HFpEF (ejection fraction, ≥45%). Cox regression assessed relations between Lp(a) and HF risk among 4 races/ethnicities. Lp(a) was examined as a continuous variable (per log unit) and using clinical cutoff values, 30 and 50 mg/dL. Lp(a) was related to greater risk of HF in whites alone: per log unit Lp(a) (hazard ratio [HR], 1.20; P=0.02); Lp(a) ≥30 mg/dL (HR, 1.69; P=0.01), Lp(a) ≥50 mg/dL (HR, 1.87; P=0.006). No significant relations were found in black, Hispanic, or Chinese participants, and significant race interactions were observed. Lp(a) was additionally related to greater risk of HFpEF in white participants: per log unit Lp(a) (HR, 1.48; P=0.001), Lp(a) ≥30 mg/dL (HR, 2.15; P=0.01), Lp(a) ≥50 mg/dL (HR, 2.60; P=0.004). Lp(a)-related risk of HF and HFpEF in whites was independent of aortic valve disease. Conclusions- In a multiethnic sample, Lp(a)-related risks of HF and HFpEF were only evident in white participants. If confirmed, these findings have implications in further Lp(a) research and clinical practice.

Comparison of Lipoprotein(a)-Levels in Patients ≥70 Years of Age With Versus Without Aortic Valve Stenosis

Although lipoprotein(a) (Lp[a]) is linked with aortic valve calcification and clinical aortic valve stenosis (AVS) in middle-aged cohorts, patients aged ≥70 years represent a majority of patients with AVS, in which mechanisms leading to AVS may differ. We sought to determine whether Lp(a) distinguishes patients ≥70 years with and without AVS. We matched 484 patients ≥70 years with AVS, scheduled for transcatheter aortic valve implantation with 484 patients without AVS by age group and gender. Lp(a) levels were compared in patients with and without AVS and stratified by presence and absence of clinical coronary artery disease (CAD) manifestation. A total of 968 patients (mean age 80 ± 5 years, 48% women) were included. When comparing patients with and without AVS, no difference in Lp(a) was observed (AVS: 17 [8; 56] mg/dl, no AVS: 18.5 [8.5; 57] mg/dl, p = 0.56). In contrast, patients with clinical CAD manifestation had higher Lp(a) levels than those without clinical CAD manifestation (coronary artery disease: 19 [9; 60] mg/dl, no coronary artery disease 15 [7; 44] mg/dl, p = 0.0006). In regression analysis, no significant association of Lp(a) with AVS was observed in unadjusted (OR [95% CI]: 0.98 [0.91 to 1.06], p = 0.59) and risk factor-adjusted models (0.98 [0.90 to 1.06], p = 0.57). However, Lp(a) was independently associated with clinical CAD manifestation (unadjusted: 1.14 [1.04 to 1.24], p = 0.003, risk factor adjusted: 1.17 [1.07 to 1.27], p = 0.0006). In conclusion, in a large cohort of patients ≥70 years, Lp(a) was associated with clinical CAD manifesation, but not with AVS. Our results suggest that in patients over 70 years, the development of AVS is not influenced by Lp(a).