Lipoprotein (a): An Update on a Marker of Residual Risk and Associated Clinical Manifestations

Lipoprotein (a) is a predictor of non-achievement of LDL-C goals in patients with chronic heart disease

INTRODUCTION AND OBJECTIVES

Lipoprotein (a) [Lp(a)] concentration influences serum low-density lipoprotein cholesterol (LDL-C) levels. How it influences the achievement of LDL-C targets established in the guidelines is not well studied. Our aim was to know the prevalence of elevated Lp(a) levels in patients with coronary artery disease, and to assess its influence on the achievement of LDL-C targets.

METHOD

We conducted a cross-sectional study in a cardiology department in Spain. A total of 870 patients with stable coronary artery disease had their lipid profile determined, including Lp(a). Patients were stratified into 2 groups according to Lp(a)>50mg/dL and Lp(a)≤50mg/dL. The association of Lp(a)>50mg/dL with achievement of LDL-C targets was assessed by logistic regression analysis.

RESULTS

The prevalence of Lp(a)>50mg/dL was 30.8%. Patients with Lp(a)>50mg/dL had higher baseline (142.30±47.54 vs. 130.47±40.75mg/dL; p=0.0001) and current (72.91±26.44 vs. 64.72±25.30mg/dL; p=0.0001), despite the fact that they were treated with more high-potency statins (77.2 vs. 70.9%; p=0.058) and more combination lipid-lowering therapy (37.7 vs. 25.7%; p=0.001). The proportion of patients achieving target LDL-C was lower in those with Lp(a)>50mg/dL. Independent predictors of having elevated Lp(a) levels>50mg/dL were the use of high-potency statins (OR 1.5; 95% CI 1.08-2.14), combination lipid-lowering therapy with ezetimibe (OR 2.0; 95% CI 1.45-2.73) and failure to achieve a LDL-C ≤55mg/dL (OR 2.3; 95% CI 1.63-3.23).

CONCLUSIONS

Elevated Lp(a) levels influence LDL-C levels and hinder the achievement of targets in patients at very high cardiovascular risk. New drugs that act directly on Lp(a) are needed in these patients.

Lipoprotein(a)-60 Years Later-What Do We Know?

Lipoprotein(a) (Lp(a)) molecule includes two protein components: apolipoprotein(a) and apoB100. The molecule is the main transporter of oxidized phospholipids (OxPL) in plasma. The concentration of this strongly atherogenic lipoprotein is predominantly regulated by the LPA gene expression. Lp(a) is regarded as a risk factor for several cardiovascular diseases. Numerous epidemiological, clinical and in vitro studies showed a strong association between increased Lp(a) and atherosclerotic cardiovascular disease (ASCVD), calcific aortic valve disease/aortic stenosis (CAVD/AS), stroke, heart failure or peripheral arterial disease (PAD). Although there are acknowledged contributions of Lp(a) to the mentioned diseases, clinicians struggle with many inconveniences such as a lack of well-established treatment lowering Lp(a), and common guidelines for diagnosing or assessing cardiovascular risk among both adult and pediatric patients. Lp(a) levels are different with regard to a particular race or ethnicity and might fluctuate during childhood. Furthermore, the lack of standardization of assays is an additional impediment. The review presents the recent knowledge on Lp(a) based on clinical and scientific research, but also highlights relevant aspects of future study directions that would approach more suitable and effective managing risk associated with increased Lp(a), as well as control the Lp(a) levels.

Lipoprotein(a) as a Higher Residual Risk for Coronary Artery Disease in Patients with Type 2 Diabetes Mellitus than without

Purpose

Lipoprotein(a) (Lp[a]) is well-known as a residual risk factor for coronary artery disease (CAD). However, the different adverse effects of Lp(a) about CAD in patients with or without type 2 diabetes mellitus (T2DM) are unclear. This study aimed to investigate the Lp(a) thresholds for CAD diagnosis in T2DM and non-T2DM patients, and further compare the Lp(a) alarm values along with optimal low-density lipoprotein cholesterol (LDL-C) level.

Methods

This retrospective study consecutively enrolled patients with suspected CAD who underwent coronary angiography in Guangdong Provincial People's Hospital between September 2014 and July 2015. A logistic regression model was established to explore the association of Lp(a) and CAD in patients. Restricted cubic splines were used to compare the threshold values of Lp(a) for CAD in patients with and without T2DM, and further in optimal LDL-C level situation.

Results

There were 1522 patients enrolled finally. After multivariable adjustment, Lp(a) was an independent risk factor for CAD in patients with T2DM (odds ratio [OR]: 1.98, 95% CI]: 1.12-3.49, p = 0.019) and without T2DM (OR: 3.42, 95% CI: 2.36-4.95, p < 0.001). In the whole population, the Lp(a) threshold of CAD was 155, while 145 mg/L for T2DM and 162 mg/L for non-T2DM ones, respectively. In patients with LDL-C<1.8 mmol/l, the alarm value of Lp(a) was even lower in T2DM than non-T2DM patients (155 vs 174 mg/L).

Conclusion

Lp(a) was a significant residual risk for CAD in patients whether with T2DM or not. And Lp(a) had a lower alarm value in T2DM patients, especially in optimal LDL-C level.

Lipoprotein(a) in clinical practice: A guide for the clinician

Cardiovascular disease (CVD) remains the leading cause of death worldwide. Serum lipoprotein(a) (Lp(a)) has been shown to be an independent and causative risk factor for atherosclerotic CVD and calcific aortic valvular disease. Lp(a) continues to be studied, with emerging insights into the epidemiology of CVD with respect to Lp(a), pathogenic mechanisms of Lp(a) and strategies to mitigate disease. There have been novel insights into genetic polymorphisms of the LPA gene, interactions between concomitant risk factors and Lp(a) based on real-world data, and metabolic pathway targets for Lp(a) reduction. This review highlights these recent advances in our understanding of Lp(a) and discusses management strategies as recommended by cardiovascular professional societies, emerging therapies for lowering Lp(a), and future directions in targeting Lp(a) to reduce CVD.

Triglyceride-Rich Lipoprotein Metabolism: Key Regulators of Their Flux

The residual risk for arteriosclerotic cardiovascular disease after optimal statin treatment may amount to 50% and is the consequence of both immunological and lipid disturbances. Regarding the lipid disturbances, the role of triglyceride-rich lipoproteins (TRLs) and their remnants has come to the forefront in the past decade. Triglycerides (TGs) stand as markers of the remnants of the catabolism of TRLs that tend to contain twice as much cholesterol as compared to LDL. The accumulation of circulating TRLs and their partially lipolyzed derivatives, known as "remnants", is caused mainly by ineffective triglyceride catabolism. These cholesterol-enriched remnant particles are hypothesized to contribute to atherogenesis. The aim of the present narrative review is to briefly summarize the main pathways of TRL metabolism, bringing to the forefront the newly discovered role of apolipoproteins, the key physiological function of lipoprotein lipase and its main regulators, the importance of the fluxes of these particles in the post-prandial period, their catabolic rates and the role of apo CIII and angiopoietin-like proteins in the partition of TRLs during the fast-fed cycle. Finally, we provide a succinct summary of the new and old therapeutic armamentarium and the outcomes of key current trials with a final outlook on the different methodological approaches to measuring TRL remnants, still in search of the gold standard.

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): Cardiovascular Disease, Aortic Stenosis and New Therapeutic Option

Atherosclerosis is a chronic and progressive inflammatory process beginning early in life with late clinical manifestation. This slow pathological trend underlines the importance to early identify high-risk patients and to treat intensively risk factors to prevent the onset and/or the progression of atherosclerotic lesions. In addition to the common Cardiovascular (CV) risk factors, new markers able to increase the risk of CV disease have been identified. Among them, high levels of Lipoprotein(a)-Lp(a)-lead to very high risk of future CV diseases; this relationship has been well demonstrated in epidemiological, mendelian randomization and genome-wide association studies as well as in meta-analyses. Recently, new aspects have been identified, such as its association with aortic stenosis. Although till recent years it has been considered an unmodifiable risk factor, specific drugs have been developed with a strong efficacy in reducing the circulating levels of Lp(a) and their capacity to reduce subsequent CV events is under testing in ongoing trials. In this paper we will review all these aspects: from the synthesis, clearance and measurement of Lp(a), through the findings that examine its association with CV diseases and aortic stenosis to the new therapeutic options that will be available in the next years.

Approach to risk stratification of atherosclerotic cardiovascular disease: Use of biomarkers and imaging in a Canadian context

OBJECTIVE

To outline the 2021 Canadian Cardiovascular Society (CCS) dyslipidemia guidelines and to present the current approaches to cardiovascular risk stratification, including the incorporation of biomarkers and imaging tests.

SOURCES OF INFORMATION

Current guidelines were reviewed and an Ovid MEDLINE literature search was performed.

MAIN MESSAGE

Cardiovascular disease (CVD) is the leading cause of global mortality, with ischemic heart disease contributing to nearly half of these deaths. Risk stratification is undertaken to identify patients who would benefit from primary prevention for atherosclerotic CVD (ASCVD), but commonly used methods for risk stratification are imperfect. The CCS guidelines endorse that the presence of risk modifiers (family history of premature ASCVD, high-sensitivity C-reactive protein level ≥2.0 mg/L, lipoprotein[a] level ≥500 mg/L [≥50 mg/dL], or coronary artery calcium >0) supports the use of statin therapy in those at intermediate risk (Framingham risk score 10% to 19.9%) who do not otherwise meet the recommendations for statin use. The CCS guidelines recommend statin therapy in patients at intermediate risk when cholesterol levels are elevated (low-density lipoprotein cholesterol level ≥3.5 mmol/L, non-high-density lipoprotein cholesterol level ≥4.2 mmol/L, or apolipoprotein B level ≥1.05 g/L). In addition, statin therapy should be considered for patients at low risk (Framingham risk score 5% to 9.9%) with elevated cholesterol levels, especially if risk modifiers are present. When cholesterol levels are not elevated, evidence still favours the use of statins in intermediate-risk patients when risk modifiers are present and in men 50 years and older and women 60 years and older with 1 additional risk factor.

CONCLUSION

Biomarkers and imaging tests have the potential to improve ASCVD risk stratification by reclassifying any patient whose risk has been inaccurately estimated by traditional methods. Recently published guidelines by the CCS suggest the use of biomarkers and imaging in certain patient groups.

Approche de la stratification du risque de maladies cardiovasculaires athéroscléreuses

Objectif

Donner un aperçu des lignes directrices de la Société canadienne de cardiologie (SCC) de 2021 sur la dyslipidémie et présenter les approches actuelles relatives à la stratification du risque cardiovasculaire, y compris l’intégration de la mesure des biomarqueurs et de l’imagerie.

Sources de l’information

Les lignes directrices actuelles ont été passées en revue, et une recherche documentaire dans Ovid MEDLINE a été effectuée.

Message principal

Les maladies cardiovasculaires (MCV) sont la principale cause de mortalité dans le monde, et les cardiopathies ischémiques contribuent à près de la moitié de ces décès. Une stratification du risque est entreprise pour identifier les patients susceptibles de bénéficier d’une prévention primaire de la MCV athéroscléreuse (MCVAS), mais les méthodes habituellement utilisées pour la stratification du risque sont imparfaites. Les lignes directrices de la SCC soutiennent que la présence de modificateurs du risque (antécédents familiaux de MCVAS prématurée, dosage de la protéine C réactive hypersensible ≥2,0 mg/L, dosage de la lipoprotéine [a] ≥500 mg/L [≥50 mg/dL] ou score calcique coronarien >0) justifie le recours à une thérapie aux statines chez les personnes à risque moyen (score de risque de Framingham de 10 à 19,9 %) qui ne sont pas autrement visées par les recommandations en faveur de l’utilisation de statines. Les lignes directrices de la SCC recommandent une thérapie aux statines chez les patients à risque modéré, lorsque leurs taux de cholestérol sont élevés (taux de cholestérol à lipoprotéines de basse densité ≥3,5 mmol/L, taux de cholestérol lié aux lipoprotéines autres que celles de haute densité ≥4,2 mmol/L ou taux d’apolipoprotéines B ≥1,05 g/L). De plus, une thérapie aux statines devrait être envisagée pour les patients à faible risque (score de risque de Framingham de 5 à 9,9 %) dont les taux de cholestérol sont élevés, surtout en présence de modificateurs du risque. Lorsque les taux de cholestérol ne sont pas élevés, des données probantes favorisent quand même le recours aux statines chez les patients à risque modéré lorsque des modificateurs du risque sont présents, de même que chez les hommes de 50 ans et plus et chez les femmes de 60 ans et plus ayant 1 facteur de risque additionnel.

Conclusion

La mesure des biomarqueurs et l’imagerie ont le potentiel d’améliorer la stratification du risque de MCVAS en reclassant les patients dont le risque avait été estimé de manière inexacte par les méthodes traditionnelles. Les lignes directrices récemment publiées par la SCC suggèrent de se servir des biomarqueurs et de l’imagerie chez certains groupes de patients.

Impact of High Lipoprotein(a) Levels on Clinical Outcomes Following Peripheral Endovascular Therapy

BACKGROUND

Elevated lipoprotein(a) (Lp[a]) levels are an independent risk factor for the development of atherosclerotic diseases, including peripheral artery disease (PAD). However, their prognostic impact in patients with PAD remains unknown.

OBJECTIVES

The aim of this study was to examine the prognostic impact of elevated Lp(a) levels in patients with PAD undergoing endovascular therapy (EVT).

METHODS

In total, 1,169 patients who underwent successful EVT for symptomatic PAD between September 2016 and August 2021 were included in this study. High Lp(a) levels were defined as >30 mg/dL. The associations of high Lp(a) levels with incident major adverse cardiovascular events (MACE) (all-cause death, myocardial infarction, and stroke) and major adverse limb events (MALE) (repeat revascularization for target limb and major amputation) were analyzed.

RESULTS

During a median follow-up period of 1.7 years (IQR: 0.6-3.0 years), 230 MACE (210 deaths, 15 myocardial infarctions, and 22 strokes) and 263 MALE (219 reinterventions and 36 major amputations) were observed. The cumulative incidence rate of MACE (48.1% vs 27.3%) and MALE (67.9% vs 27.2%) was significantly higher in patients with high Lp(a) levels (P < 0.001 for both). The adjusted HR were 1.93 (95% CI: 1.44-2.59; P < 0.001) for MACE and 4.15 (95% CI: 3.14-5.50; P < 0.001) for MALE. These associations were not influenced by low-density lipoprotein cholesterol levels or statin administration (P for interaction >0.05 for all).

CONCLUSIONS

Elevated Lp(a) levels were independently associated with incident MACE and MALE in patients with PAD treated with revascularization irrespective of low-density lipoprotein cholesterol level and statin administration.

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.

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.

Value of repeated measurements of lipoprotein (a) to assess cardiovascular risk: a retrospective study

Background: High plasma concentrations of lipoprotein (a) [Lp(a)] are associated with an increased cardiovascular risk. Current guidelines recommend measurement of only a single Lp(a) in an individual's lifetime under specific circumstances to improve cardiovascular risk prediction. Accordingly, the question raised is the number of false positives and negatives missed through only a single measurement.Methods: All Lp(a) measurements between 2004 and March 2021 were retrieved from the laboratory database of the Erasme hospital. Only patients with repeated measurement were included. The first and subsequent Lp(a) measurement were compared. Two different cohorts were studied as a result of a change in Lp(a) determination methodology (n = 2049 and n = 309, respectively). The effects of a third Lp(a) measurement were assessed through binary analyses (n = 678). The 180 mg/dl (430 nmol/L) threshold recommended in the ESC guidelines was assessed first. Analysis was repeated for 100, 70 and 50 mg/dl thresholds of raised Lp(a) levels.Results: A low rate of false negatives (0.8%-1%) and false positives (0.6-0.3%) were revealed with two Lp(a) measurements. There was no difference in regards to the divergent Lp(a) thresholds nor the measurement of Lp(a) on two or three occasions.Conclusion: The present study showed Lp(a) determination to be reproducible. A single measurement is sufficient to assess if a patient exceeds various cut-off values of elevated Lp(a) levels.

Association of Lipoprotein(a) With Atherosclerotic Plaque Progression

BACKGROUND

Lipoprotein(a) [Lp(a)] is associated with increased risk of myocardial infarction, although the mechanism for this observation remains uncertain.

OBJECTIVES

This study aims to investigate whether Lp(a) is associated with adverse plaque progression.

METHODS

Lp(a) was measured in patients with advanced stable coronary artery disease undergoing coronary computed tomography angiography at baseline and 12 months to assess progression of total, calcific, noncalcific, and low-attenuation plaque (necrotic core) in particular. High Lp(a) was defined as Lp(a) ≥ 70 mg/dL. The relationship of Lp(a) with plaque progression was assessed using linear regression analysis, adjusting for body mass index, segment involvement score, and ASSIGN score (a Scottish cardiovascular risk score comprised of age, sex, smoking, blood pressure, total and high-density lipoprotein [HDL]-cholesterol, diabetes, rheumatoid arthritis, and deprivation index).

RESULTS

A total of 191 patients (65.9 ± 8.3 years of age; 152 [80%] male) were included in the analysis, with median Lp(a) values of 100 (range: 82 to 115) mg/dL and 10 (range: 5 to 24) mg/dL in the high and low Lp(a) groups, respectively. At baseline, there was no difference in coronary artery disease severity or plaque burden. Patients with high Lp(a) showed accelerated progression of low-attenuation plaque compared with low Lp(a) patients (26.2 ± 88.4 mm3 vs -0.7 ± 50.1 mm3; P = 0.020). Multivariable linear regression analysis confirmed the relation between Lp(a) and low-attenuation plaque volume progression (β = 10.5% increase for each 50 mg/dL Lp(a), 95% CI: 0.7%-20.3%). There was no difference in total, calcific, and noncalcific plaque volume progression.

CONCLUSIONS

Among patients with advanced stable coronary artery disease, Lp(a) is associated with accelerated progression of coronary low-attenuation plaque (necrotic core). This may explain the association between Lp(a) and the high residual risk of myocardial infarction, providing support for Lp(a) as a treatment target in atherosclerosis.

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.

Elevated serum lipoprotein(a) is significantly associated with angiographic progression of coronary artery disease

Background

Lipoprotein(a)[Lp(a)] has been considered as an independent risk factor for coronary artery disease (CAD). The present study aimed to evaluate the association between baseline serum Lp(a) and CAD progression determined by angiographic score.

Methods

A total of 814 patients who had undergone two or more coronary computed tomography angiography at least 6 months apart were consecutively enrolled and the coronary severity was determined by the Gensini score system. Patients were stratified into two groups according to Lp(a)>300 mg/L and Lp(a) ≤ 300 mg/L or classified as “progressors” and “non‐progressors” based on the Gensini score rate of change per year. The association of continuous Lp(a) and Lp(a)>300 mg/L with CAD progression were respectively assessed by logistic regression analysis. Moreover, further evaluation of those association was performed in subgroups of the study population.

Results

Patients in the “progressors” group had significant higher Lp(a) levels. Furthermore, the multivariate logistic regression analysis showed that elevated Lp(a) (odds ratio [OR]: 1.451, 95% confidence interval [CI]: 1.177–1.789, p<.001) and Lp(a)>300 mg/L (OR:1.642, 95% CI:1.018–2.649, p = .042) were positively associated with CAD progression after adjusting for confounding factors. In addition, those relation seemed to be more prominent in subjects with lower body mass index (OR: 1.880, 95% CI: 1.224–2.888, p for interaction = .060).

Conclusions

Elevated baseline serum Lp(a) is positively and independently associated with angiographic progression of CAD, particularly in participants with relatively low body mass index. Therefore, Lp(a) could be a potent risk factor for CAD progression, assisting in early risk stratification in cardiovascular patients.

Lipoprotein(a) Where Do We Stand? From the Physiopathology to Innovative Terapy

A number of epidemiologic studies have demonstrated a strong association between increasing lipoprotein a [Lp(a)] and cardiovascular disease. This correlation was demonstrated independent of other known cardiovascular (CV) risk factors. Screening for Lp(a) in the general population is not recommended, although Lp(a) levels are predominantly genetically determined so a single assessment is needed to identify patients at risk. In 2019 ESC/EAS guidelines recommend Lp(a) measurement at least once a lifetime, fo subjects at very high and high CV risk and those with a family history of premature cardiovascular disease, to reclassify patients with borderline risk. As concerning medications, statins play a key role in lipid lowering therapy, but present poor efficacy on Lp(a) levels. Actually, treatment options for elevated serum levels of Lp(a) are very limited. Apheresis is the most effective and well tolerated treatment in patients with high levels of Lp(a). However, promising new therapies, in particular antisense oligonucleotides have showed to be able to significantly reduce Lp(a) in phase II RCT. This review provides an overview of the biology and epidemiology of Lp(a), with a view to future therapies.

Performance evaluation of five lipoprotein(a) immunoassays on the Roche cobas c501 chemistry analyzer

Objectives

Measurement of lipoprotein(a) [Lp(a)] is used in risk assessment of atherosclerotic cardiovascular disease (ASCVD). The aim of the current study was to evaluate performance characteristic of five different Lp(a) assays using the cobas c501 (Roche Diagnostics) analyzer.

Design and methods

Lp(a) was measured using five Lp(a) assays (Diazyme, Kamiya, MedTest, Randox, and Roche) configured to mg/dL units. Assays from Diazyme and Kamiya were also configured using nmol/L units in separate experiments. Studies included sensitivity, imprecision, linearity, method comparison, and evaluation of healthy subjects. Imprecision (intra-day, 20 replicates; inter-day, duplicates twice daily for five days) and linearity were evaluated using patient pools. Linearity assessed a minimum of five patient splits spanning the analytical measurement range (AMR). Method comparison used 80 residual serum samples. Specimens from 120 self-reported healthy subjects (61 females / 59 males) were also tested. Method comparison for two assays in nmol/L units was conducted using 96 residual serum samples.

Results

Assay sensitivities met all manufacturer claims. Imprecision studies demonstrated %CVs ranging from 2.5 to 5.2% for the low pool (average concentration from 7.3 to 12.4 ​mg/dL); high pool %CVs ranged from 0.8 to 3.0% (average concentrations from 31.5–50.2 ​mg/dL). Linearity was confirmed for all assays. Variation in accuracy was observed when comparing results to an all method average. Lp(a) results were higher in females versus males in self-reported healthy subjects.

Conclusions

All assays performed according to manufacturer described performance characteristics, although differences were observed across Lp(a) assays tested when compared to an all method average.

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Five automated assays for Lp(a) measurement (mg/dL units) were compared.

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Differences in accuracy were observed across the methods investigated.

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Two assays were also compared using nmol/L units.

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More Lp(a) assay traceability to the international reference material is needed.