Lipoprotein(a) and Hyperinsulinemia in Healthy Normal-weight, Prepubertal Mexican Children

Background. Given the numerous gaps in our knowledge about the biological interactions of lipoprotein(a) [Lp(a)], we determined whether Lp(a) was associated with hyperinsulinemia in healthy normal-weight, prepubertal children.Methods. A total of 131 healthy normal-weight Mexican children aged 6 to 9 years at Tanner stage 1 who were born appropriate for gestational age were enrolled in a case-control study. Children with hyperinsulinemia were allocated into the case group (n = 32), and children with normal insulin levels were allocated into the control group (n = 99). Birth weight, age, and body mass index were matching criteria. Multivariate logistic regression analysis was used to compute the odds ratio (OR) between Lp(a) and both hyperinsulinemia and insulin resistance. Furthermore, a multivariate linear regression analysis was performed to evaluate the association between Lp(a) and both insulin levels and HOMA-IR. Both models were adjusted by sex, age, birth weight, and body mass index.Results. The median (25-75 percentile) serum levels of Lp(a) [20.0 (13.7-29.6) versus 14.6 (10.6-26.7) mg/dL, p = .003] and insulin [24.5 (6.0-30) versus 7.9 (4.3-9.0) µU/L, p < .0005] were higher in the case group than in the control group. The logistic regression analysis showed that Lp(a) was associated with hyperinsulinemia (OR 5.86; 95%CI 2.5-13.6, p < .0005) and insulin resistance (OR 2.01; 95%CI 1.1-9.9, p = .004). In addition, the linear regression analysis showed a significant association between serum Lp(a) and insulin levels (β 11.1; 95%CI 1.8-10.9, p < .0001) and the HOMA-IR index (β 2.606; 95%CI 2.3-2.9, p < .0005).Conclusion. Lp(a) was associated with hyperinsulinemia and insulin resistance in healthy normal-weight, prepubertal children.

Working towards full eradication of lipid-driven cardiovascular risk?

Lipid-driven cardiovascular disease (CVD) risk is caused by atherogenic apolipoprotein B (apoB) particles containing low-density lipoprotein cholesterol (LDL-C), triglycerides and lipoprotein(a) [Lp(a)] and resembles a large and modifiable proportion of the total CVD risk. While a surplus of novel lipid-lowering therapies has been developed in recent years, management of lipid-driven CVD risk in the Netherlands remains suboptimal. To lower LDL‑C levels, statins, ezetimibe and proprotein convertase subtilisin/kexin type 9 inhibiting antibodies are the current standard of therapy. With the approval of bempedoic acid and the silencing RNA inclisiran, therapeutic options are expanding continuously. Although the use of triglyceride-lowering therapies remains a matter of debate, post hoc analyses consistently show a benefit in subsets of patients with high triglyceride or low high-density lipoprotein cholesterol levels. Pemafibrate and novel apoC-III could be efficacious options when approved for clinical use. Lp(a)-lowering therapies such as pelacarsen are under clinical investigation, offering a potent Lp(a)-lowering effect. If proven effective in reducing cardiovascular endpoints, Lp(a) lowering holds promise to be the third axis of effective lipid-lowering therapies. Using these three components of lipid-lowering treatment, the contribution of apoB-containing lipid particles to the CVD risk may be fully eradicated in the next decade.

Evaluation of cardiovascular events and progression to end-stage renal disease in patients with dyslipidemia and chronic kidney disease from the North-Eastern area of Romania

PURPOSE

The aim of this prospective cohort study was: to identify the association between different biomarkers [proprotein convertase subtilisin/kexin 9-PCSK9, lipoprotein(a)-Lp(a) and high-sensitivity C-reactive protein-hsCRP] and the cardiovascular events; to evaluate the relationship between the 3 biomarkers mentioned above and the renal outcomes that contributed to end-stage renal disease (ESRD).

METHODS

We studied 110 patients with chronic kidney disease (CKD) stages 2 to 4. The identification of the new cardiovascular events and the renal outcomes were performed by clinical and paraclinical explorations.

RESULTS

350 patients were examined and 110 (31.4%) were included in this study. The mean age was 55.6 ± 10.9 years, with a higher number of men compared to women. The CKD patients with de novo cardiovascular events and new renal outcome during the study, had significantly increased values of total cholesterol (TC), low density cholesterol lipoprotein (LDL-C) at 6 and 12 months and higher levels of Lp(a), PCSK9, hsCRP and low ankle-brachial index (ABI) and ejection fraction (EF) values compared to patients without cardiovascular and renal events. In CKD patients, PCSK9 > 220 ng/mL was a predictor of cardiovascular events, while the EF < 50% was a predictor for renal outcomes. For CKD patients with PCSK9 > 220 ng/mL and hsCRP > 3 mg/L levels, the time-interval for the new cardiovascular and renal events occurrence were significantly decreased compared to patients displaying low values of these biomarkers.

CONCLUSION

The results of this study show that PCSK9 > 220 ng/mL was predictor for cardiovascular events, while EF < 50% was predictor for CKD progression to ESRD. PCSK9 > 220 ng/mL and hsCRP > 3 mg/L were associated with the occurrence of renal and cardiovascular events earlier.

Lipoprotein(a)

Lipoprotein(a) [Lp(a)] is an atherogenic lipoprotein with a strong genetic regulation. Up to 90% of the concentrations are explained by a single gene, the LPA gene. The concentrations show a several-hundred-fold interindividual variability ranging from less than 0.1 mg/dL to more than 300 mg/dL. Lp(a) plasma concentrations above 30 mg/dL and even more above 50 mg/dL are associated with an increased risk for cardiovascular disease including myocardial infarction, stroke, aortic valve stenosis, heart failure, peripheral arterial disease, and all-cause mortality. Since concentrations above 50 mg/dL are observed in roughly 20% of the Caucasian population and in an even higher frequency in African-American and Asian-Indian ethnicities, it can be assumed that Lp(a) is one of the most important genetically determined risk factors for cardiovascular disease.Carriers of genetic variants that are associated with high Lp(a) concentrations have a markedly increased risk for cardiovascular events. Studies that used these genetic variants as a genetic instrument to support a causal role for Lp(a) as a cardiovascular risk factor are called Mendelian randomization studies. The principle of this type of studies has been introduced and tested for the first time ever with Lp(a) and its genetic determinants.There are currently no approved pharmacologic therapies that specifically target Lp(a) concentrations. However, some therapies that target primarily LDL cholesterol have also an influence on Lp(a) concentrations. These are mainly PCSK9 inhibitors that lower LDL cholesterol by 60% and Lp(a) by 25-30%. Furthermore, lipoprotein apheresis lowers both, Lp(a) and LDL cholesterol, by about 60-70%. Some sophisticated study designs and statistical analyses provided support that lowering Lp(a) by these therapies also lowers cardiovascular events on top of the effect caused by lowering LDL cholesterol, although this was not the main target of the therapy. Currently, new therapies targeting RNA such as antisense oligonucleotides (ASO) or small interfering RNA (siRNA) against apolipoprotein(a), the main protein of the Lp(a) particle, are under examination and lower Lp(a) concentrations up to 90%. Since these therapies specifically lower Lp(a) concentrations without influencing other lipoproteins, they will serve the last piece of the puzzle whether a decrease of Lp(a) results also in a decrease of cardiovascular events.

Association of lipoprotein(a) with intrinsic and on-clopidogrel platelet reactivity

Lipoprotein(a) [Lp(a)] is an independent, genetically determined, and causal risk factor for cardiovascular disease. Laboratory data have suggested an interaction of Lp(a) with platelet function, potentially caused by its interaction with platelet receptors. So far, the potential association of Lp(a) with platelet activation and reactivity has not been proven in larger clinical cohorts. This study analyzed intrinsic platelet reactivity before loading with clopidogrel 600 mg and on-treatment platelet reactivity tested 24 h following loading in patients undergoing elective coronary angiography. Platelet reactivity was tested by optical aggregometry following stimulation with collagen or adenosine diphosphate as well as by flow cytometry. Lp(a) levels were directly measured in all patients from fresh samples. The present analysis included 1912 patients. Lp(a) levels ranged between 0 and 332 mg/dl. There was a significant association of rising levels of Lp(a) with a higher prevalence of a history of ischemic heart disease (p < 0.001) and more extensive coronary artery disease (p = 0.001). Results for intrinsic (p = 0.80) and on-clopidogrel platelet reactivity (p = 0.81) did not differ between quartiles of Lp(a) levels. Flow cytometry analyses of expression of different platelet surface proteins (CD41, CD62P or PAC-1) confirmed these findings. Correlation analyses of levels of Lp(a) with any of the tested platelet activation markers did not show any correlation. The present data do not support the hypothesis of an interaction of Lp(a) with platelet reactivity.

Lipoprotein(a) is associated with large artery atherosclerosis stroke aetiology and stroke recurrence among patients below the age of 60 years: results from the BIOSIGNAL study

AIMS

Lipoprotein(a) [Lp(a)] is a recognized causal risk factor for atherosclerotic cardiovascular disease but its role for acute ischaemic stroke (AIS) is controversial. In this study, we evaluated the association of Lp(a) with large artery atherosclerosis (LAA) stroke and risk of recurrent cerebrovascular events in AIS patients.

METHODS AND RESULTS

For this analysis of the prospective, observational, multicentre BIOSIGNAL cohort study we measured Lp(a) levels in plasma samples of 1733 primarily Caucasian (98.6%) AIS patients, collected within 24 h after symptom onset. Primary outcomes were LAA stroke aetiology and recurrent cerebrovascular events (ischaemic stroke or transient ischaemic attack) within 1 year. We showed that Lp(a) levels are independently associated with LAA stroke aetiology [adjusted odds ratio 1.48, 95% confidence interval (CI) 1.14-1.90, per unit log10Lp(a) increase] and identified age as a potent effect modifier (Pinteraction =0.031) of this association. The adjusted odds ratio for LAA stroke in patients aged <60 years was 3.64 (95% CI 1.76-7.52) per unit log10Lp(a) increase and 4.04 (95% CI 1.73-9.43) using the established cut-off ≥100 nmol/l. For 152 recurrent cerebrovascular events, we did not find a significant association in the whole cohort. However, Lp(a) levels ≥100 nmol/l were associated with an increased risk for recurrent events among patients who were either <60 years [adjusted hazard ratio (HR) 2.40, 95% CI 1.05-5.47], had evident LAA stroke aetiology (adjusted HR 2.18, 95% CI 1.08-4.40), or had no known atrial fibrillation (adjusted HR 1.60, 95% CI 1.03-2.48).

CONCLUSION

Elevated Lp(a) was independently associated with LAA stroke aetiology and risk of recurrent cerebrovascular events among primarily Caucasian individuals aged <60 years or with evident arteriosclerotic disease.

The Predictive Value of Lp(a) for Adverse Cardiovascular Event in ACS Patients With an Achieved LDL-C Target at Follow Up After PCI

Low-density lipoprotein cholesterol (LDL-C) is a traditional and important risk factor for atherosclerotic cardiovascular disease (CVD). Recently, lipoprotein (a) (lp(a)) attracts considerable attention as a residual risk factor for CVD. However, the roles of lp(a) in acute coronary syndrome (ACS) patients with well-controlled LDL-C (≤1.8mmol/L) after percutaneous coronary intervention (PCI) remain unclear. Current study results demonstrated that occurrence of major adverse cardiovascular events (MACE) and recurrent myocardial infarction (MI) increased with the Lp(a) increasing in patients with LDL-C≤1.8mmol/L at 1-month follow-up. In relatively low-risk patients presented with ACS and underwent PCI (LDL-C ≤1.8mmol/L at 1-month follow-up), lp(a) is still independently related to adverse prognosis. Further researches of targeted therapy against lp(a) are warranted.

The Role of RNA-Targeted Therapeutics to Reduce ASCVD Risk: What Have We Learned Recently?

PURPOSE OF REVIEW

To discuss advances on the RNA-targeted therapies to treat dyslipidemia with the aim of reducing atherosclerotic cardiovascular disease (ASCVD).

RECENT FINDINGS

Genetic studies have paved the way for therapies that reduce translation of proteins that play causal roles in dyslipidemia and atherosclerosis like proprotein convertase subtilisin/kexin type 9 (PCSK9), apolipoprotein B-100 (apoB), apolipoprotein(a) [apo(a)], apolipoprotein C3 (apoC3), and angiopoietin-like 3 (ANGPTL3). Either antisense oligonucleotide (ASO) therapies and small interfering RNA (siRNA) molecules inhibit protein synthesis and consequently improve dyslipidemia. Most of these molecules contain N-acetylgalactosamine (GalNAc) moieties that have high specificity for hepatocytes and therefore reduce concentration in other tissues. Inclisiran, an siRNA for PCSK9, has shown robust LDL-C reductions, with good tolerability, in severe forms of hypercholesterolemia as well as in high cardiovascular disease patients with injections every 3 to 6 months. Pelacarsen is an ASO against apolipoprotein(a) that reduces Lp(a) up to 80% with good tolerability. Either inclisiran or pelacarsen is being tested to show it can prevent ASCVD. AMG 890, an siRNA compound aimed at reducing apo(a) synthesis, is also under investigation. Volanesorsen is an ASO against apoC3 that reduces triglyceride levels up to 70% and is being tested in severe hypertriglyceridemic patients. Vupanorsen is an ASO against ANGPTL3 that reduced triglyceride levels 36-53% among moderate hypertriglyceridemic individuals. Interestingly, it also reduces ApoC3 and non-HDL cholesterol and apoB; however, it lowers HDL cholesterol. RNA-targeted therapies are being extensively tested for dyslipidemia treatment with promising results.

Associations of Lipoprotein(a) With Coronary Atherosclerotic Burden and All-Cause Mortality in Patients With ST-Segment Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention

Background: The coronary atherosclerotic burden in patients with ST-segment elevation myocardial infarction (STEMI) has been identified as the main predictor of prognosis. However, the association of lipoprotein(a) [Lp(a)], a well-established proatherogenic factor, with atherosclerotic burden in patients with STEMI is unclear.

Methods: In total, 1,359 patients who underwent percutaneous coronary intervention (PCI) for STEMI were included in analyses. Three prespecified models with adjustment for demographic parameters and risk factors were evaluated. Generalized additive models and restricted cubic spline analyses were used to assess the relationships of Lp(a) with Gensini scores and the no-reflow phenomenon. Kaplan–Meier curves were generated to explore the predictive value of Lp(a) for long-term all-cause mortality. Furthermore, mRNA expression levels of LPA in different groups were compared using the GEO database.

Results: Patients in the highest tertile according to Lp(a) levels had an increased incidence of heart failure during hospitalization. Furthermore, patients with high levels of Lp(a) (>19.1 mg/dL) had sharply increased risks for a higher Gensini score (P_{for trend} = 0.03) and no-reflow (P_{for trend} = 0.002) after adjustment for demographic parameters and risk factors. During a median follow-up of 930 days, 132 deaths (9.95%) were registered. Patients with high levels of Lp(a) (>19.1 mg/dL) had the worst long-term prognosis (P_{for trend} < 0.0001). In a subgroup analysis, patients with higher Lp(a) still had the highest all-cause mortality. Additionally, the mRNA expression levels of LPA in patients with STEMI with lower cardiac function were higher than those in other groups (P = 0.003). A higher coronary atherosclerotic burden was correlated with higher LPA expression (P = 0.01).

Conclusion: This study provides the first evidence that Lp(a) (at both the protein and mRNA levels) is independently associated with coronary atherosclerotic lesions and prognosis in patients with STEMI treated with PCI.

Clinical Trial Registration:http://www.chictr.org.cn/index.aspx, identifier: ChiCTR1900028516.

The association of lipoprotein(a) and intraplaque neovascularization in patients with carotid stenosis: a retrospective study

Background

Lipoprotein(a) is genetically determined and increasingly recognized as a major risk factor for arteriosclerotic cardiovascular disease. We examined whether plasma lipoprotein(a) concentrations were associated with intraplaque neovascularization (IPN) grade in patients with carotid stenosis and in terms of increasing plaque susceptibility to haemorrhage and rupture.

Methods

We included 85 patients diagnosed with carotid stenosis as confirmed using carotid ultrasound who were treated at Guangdong General Hospital. Baseline data, including demographics, comorbid conditions and carotid ultrasonography, were recorded. The IPN grade was determined using contrast-enhanced ultrasound through the movement of the microbubbles. Univariate and multivariate binary logistic regression analyses were used to evaluate the association between lipoprotein(a) and IPN grade, with stepwise adjustment for covariates including age, sex, comorbid conditions and statin therapy (model 1), total cholesterol, triglyceride, low-density lipoprotein cholesterol calculated by Friedwald's formula, high-density lipoprotein cholesterol, apolipoprotein A and apolipoprotein B (model 2), maximum plaque thickness and total carotid maximum plaque thickness, degree of carotid stenosis and internal carotid artery (ICA) occlusion (model 3).

Results

Lipoprotein(a) was a significant predictor of higher IPN grade in binary logistic regression before adjusting for other risk factors (odds ratio [OR] 1.238, 95% confidence interval [CI] (1.020, 1.503), P = 0.031). After adjusting for other risk factors, lipoprotein(a) still remained statistically significant in predicting IPN grade in all model. (Model 1: OR 1.333, 95% CI 1.074, 1.655, P = 0.009; Model 2: OR 1.321, 95% CI 1.059, 1.648, P = 0.014; Model 3: OR 1.305, 95% CI 1.045, 1.628, P = 0.019). Lp(a) ≥ 300 mg/L is also significantly related to IPN compare to < 300 mg/L (OR 2.828, 95% CI 1.055, 7.580, P = 0.039) as well as in model 1, while in model 2 and model 3 there are not significant difference.

Conclusions

Plasma lipoprotein(a) concentrations were found to be independently associated with higher IPN grade in patients with carotid stenosis. Lowering plasma lipoprotein(a) levels may result in plaque stabilization by avoiding IPN formation.

Beyond Lipoprotein(a) plasma measurements: Lipoprotein(a) and inflammation

Genome wide association, epidemiological, and clinical studies have established high lipoprotein(a) [Lp(a)] as a causal risk factor for atherosclerotic cardiovascular disease (ASCVD). Lp(a) is an apoB100 containing lipoprotein covalently bound to apolipoprotein(a) [apo(a)], a glycoprotein. Plasma Lp(a) levels are to a large extent determined by genetics. Its link to cardiovascular disease (CVD) may be driven by its pro-inflammatory effects, of which its association with oxidized phospholipids (oxPL) bound to Lp(a) is the most studied. Various inflammatory conditions, such as rheumatoid arthritis (RA), systemic lupus erythematosus, acquired immunodeficiency syndrome, and chronic renal failure are associated with high Lp(a) levels. In cases of RA, high Lp(a) levels are reversed by interleukin-6 receptor (IL-6R) blockade by tocilizumab, suggesting a potential role for IL-6 in regulating Lp(a) plasma levels. Elevated levels of IL-6 and IL-6R polymorphisms are associated with CVD. Therapies aimed at lowering apo(a) and thereby reducing plasma Lp(a) levels are in clinical trials. Their results will determine if reductions in apo(a) and Lp(a) decrease cardiovascular outcomes. As we enter this new arena of available treatments, there is a need to improve our understanding of mechanisms. This review will focus on the role of Lp(a) in inflammation and CVD.

Potent lipoprotein(a) lowering following apolipoprotein(a) antisense treatment reduces the pro-inflammatory activation of circulating monocytes in patients with elevated lipoprotein(a)

Aims

Elevated lipoprotein(a) [Lp(a)] is strongly associated with an increased cardiovascular disease (CVD) risk. We previously reported that pro-inflammatory activation of circulating monocytes is a potential mechanism by which Lp(a) mediates CVD. Since potent Lp(a)-lowering therapies are emerging, it is of interest whether patients with elevated Lp(a) experience beneficial anti-inflammatory effects following large reductions in Lp(a).

Methods and results

Using transcriptome analysis, we show that circulating monocytes of healthy individuals with elevated Lp(a), as well as CVD patients with increased Lp(a) levels, both have a pro-inflammatory gene expression profile. The effect of Lp(a)-lowering on gene expression and function of monocytes was addressed in two local sub-studies, including 14 CVD patients with elevated Lp(a) who received apolipoprotein(a) [apo(a)] antisense (AKCEA-APO(a)-LRx) (NCT03070782), as well as 18 patients with elevated Lp(a) who received proprotein convertase subtilisin/kexin type 9 antibody (PCSK9ab) treatment (NCT02729025). AKCEA-APO(a)-LRx lowered Lp(a) by 47% and reduced the pro-inflammatory gene expression in monocytes of CVD patients with elevated Lp(a), which coincided with a functional reduction in transendothelial migration capacity of monocytes ex vivo (−17%, P < 0.001). In contrast, PCSK9ab treatment lowered Lp(a) by 16% and did not alter transcriptome nor functional properties of monocytes, despite an additional reduction of 65% in low-density lipoprotein cholesterol (LDL-C).

Conclusion

Potent Lp(a)-lowering following AKCEA-APO(a)-LRx, but not modest Lp(a)-lowering combined with LDL-C reduction following PCSK9ab treatment, reduced the pro-inflammatory state of circulating monocytes in patients with elevated Lp(a). These ex vivo data support a beneficial effect of large Lp(a) reductions in patients with elevated Lp(a).

Coronary heart disease risk: Low-density lipoprotein and beyond

Coronary heart disease (CHD) is the leading cause of morbidity and mortality world-wide and has been characterized as a chronic immunoinflammatory, fibroproliferative disease fueled by lipids. Great advances have been made in elucidating the complex mechanistic interactions among risk factors associated with CHD, yielding abundant success towards preventive measures and the development of pharmaceuticals to prevent and treat CHD via attenuation of lipoprotein-mediated risk. However, significant residual risk remains. Several potentially modifiable CHD risk factors ostensibly contributing to this residual risk have since come to the fore, including systemic inflammation, diabetes mellitus, high-density lipoprotein, plasma triglycerides (TG) and remnant lipoproteins (RLP), lipoprotein(a) (Lp[a]), and vascular endothelial dysfunction (ED). Herein, we summarize the body of evidence implicating each of these risk factors in residual CHD risk.

Prevalence and influence of LPA gene variants and isoform size on the Lp(a)-lowering effect of pelacarsen

BACKGROUND AND AIMS

Antisense oligonucleotides (ASOs) targeting LPA to lower lipoprotein(a) [Lp(a]] are in clinical trials. Patients have been recruited according to various Lp(a) thresholds, but the prevalence of LPA genetic variants and their effect on efficacy of these ASOs are not well described.

METHODS

We analyzed data from 4 clinical trials of the ASO pelacarsen targeting apolipoprotein(a) that included 455 patients. Common LPA genetic variants rs10455872 and rs3798220, major and minor isoform size, and changes in Lp(a), LDL-C, apoB, OxPL-apoB and OxPL-apo(a) were analyzed according to categories of baseline Lp(a).

RESULTS

The prevalence of carrier status for rs10455872 and rs3798220 combined ranged from 25.9% in patients with Lp(a) in the 75 - <125 nmol/L range to 77.1% at Lp(a) ≥375 nmol/L. The prevalence of homozygosity for rs3798220, rs10455872 and for double heterozygosity in category of Lp(a) ≥375 nmol/L was 6.3%, 14.6% and 12.5%, respectively. Isoform size decreased with increasing Lp(a) plasma levels, with 99.3% of patients with Lp(a) ≥175 nmol/L having ≤20 KIV repeats in the major isoform. The mean percent reduction from baseline in Lp(a), OxPL-apoB and OxPL-apo(a) in response to pelacarsen was not affected by the presence of rs10455872 and rs3798220, isoform size or baseline Lp(a) at all doses studied.

CONCLUSIONS

In patients randomized to Lp(a) lowering trials, LPA genetic variants are common, but a sizable proportion do not carry common variants associated with elevated Lp(a). In contrast, the major isoform size was almost uniformly ≤20 KIV repeats in patients with Lp(a) ≥175 nmol/L. The Lp(a) and OxPL lowering effects of pelacarsen were independent of both LPA genetic variants and isoform size.

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.

•

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.

Lipid Lowering Drugs: Present Status and Future Developments

Purpose of review

Based on the recent data of the DA VINCI study, it is clear that, besides utilization of statins, there is a need to increase non-statin lipid lowering approaches to reduce the cardiovascular burden in patients at highest risk.

Recent findings

For hypercholesterolemia, the small synthetic molecule bempedoic acid has the added benefit of selective liver activation, whereas inclisiran, a hepatic inhibitor of the PCSK9 synthesis, has comparable effects with PCSK9 monoclonal antibodies. For hypertriglyceridemia, cardiovascular benefit has been achieved by the use of icosapent ethyl, whereas results with pemafibrate, a selective agonist of PPAR-α, are eagerly awaited. In the era of RNA-based therapies, new options are offered to dramatically reduce levels of lipoprotein(a) (APO(a)L_RX) and of triglycerides (ANGPTL3L_RX and APOCIII-L_Rx).

Summary

Despite the demonstrated benefits of statins, a large number of patients still remain at significant risk because of inadequate LDL-C reduction or elevated blood triglyceride-rich lipoproteins or lipoprotein(a). The area of lipid modulating agents is still ripe with ideas and major novelties are to be awaited in the next few years.

LDL Apheresis and Lp (a) Apheresis: A Clinician's Perspective

Purpose of Review

Lipoprotein apheresis is the most effective means of lipid-lowering therapy. However, it’s a semi-invasive, time consuming, and chronic therapy with variable adherence. There are still no specific guideline recommendations for the management of patients on lipid apheresis. The purpose of this review is to discuss the clinical indications and major drawbacks of lipid apheresis in the light of recent evidence.

Recent Findings

Lipoprotein apheresis should be initiated at early ages and performed frequently to receive the expected cardiovascular benefits. However, in clinical practice, most patients experience ineffective apheresis and fail to reach lipid targets. This real-world failure is due to several factors including late diagnosis, delayed referral, and improper frequency of procedures. All these denote that awareness is still low among physicians. Another important factor is the semi-invasive, time consuming nature of the apheresis, leading to high refusal and low adherence rates. Moreover, apheresis decreases quality of life and increases the risk of depression. Mental status is also deteriorated in patients with familial hypercholesterolemia on lipid apheresis. New effective lipid lowering agents are underway with promising cardiovascular results.

Summary

To overcome the drawbacks, a structured approach, including standardized protocols for lipoprotein apheresis with regular cardiovascular follow-up is warranted. New effective lipid lowering agents with documented cardiovascular benefit, should be integrated into the treatment algorithms of patients on lipoprotein apheresis.

Development of an LC-MS/MS Proposed Candidate Reference Method for the Standardization of Analytical Methods to Measure Lipoprotein(a)

BACKGROUND

Use of lipoprotein(a) concentrations for identification of individuals at high risk of cardiovascular diseases is hampered by the size polymorphism of apolipoprotein(a), which strongly impacts immunochemical methods, resulting in discordant values. The availability of a reference method with accurate values expressed in SI units is essential for implementing a strategy for assay standardization.

METHOD

A targeted LC-MS/MS method for the quantification of apolipoprotein(a) was developed based on selected proteotypic peptides quantified by isotope dilution. To achieve accurate measurements, a reference material constituted of a human recombinant apolipoprotein(a) was used for calibration. Its concentration was assigned using an amino acid analysis reference method directly traceable to SI units through an unbroken traceability chain. Digestion time-course, repeatability, intermediate precision, parallelism, and comparability to the designated gold standard method for lipoprotein(a) quantification, a monoclonal antibody-based ELISA, were assessed.

RESULTS

A digestion protocol providing comparable kinetics of digestion was established, robust quantification peptides were selected, and their stability was ascertained. Method intermediate imprecision was below 10% and linearity was validated in the 20-400 nmol/L range. Parallelism of responses and equivalency between the recombinant and endogenous apo(a) were established. Deming regression analysis comparing the results obtained by the LC-MS/MS method and those obtained by the gold standard ELISA yielded y = 0.98*ELISA +3.18 (n = 64).

CONCLUSIONS

Our method for the absolute quantification of lipoprotein(a) in plasma has the required attributes to be proposed as a candidate reference method with the potential to be used for the standardization of lipoprotein(a) assays.

The correlation between lipoprotein(a) and coronary atherosclerotic lesion is stronger than LDL-C, when LDL-C is less than 104 mg/dL

Background

Lp(a) and LDL-C are both risk factors of atherosclerotic cardiovascular disease (ASCVD). But there was a contradiction point in LDL-C and Lp(a) control. The appropriate level of LDL-C and Lp(a) in the prevention of ASCVD is still pending.

Objective

To investigate the correlation of Lp(a) and coronary atherosclerotic lesion, and find out the balance point in LDL-C and Lp(a) control.

Method

3449 patients were divided to coronary atherosclerotic heart disease (CAHD) Group and Non-CAHD Group based on the result of coronary angiography. The clinical characteristics were compared, and Logistic regressions were applied to find the CAHD risk factors in total, High-LDL-C Group (LDL-C ≥ 100 mg/dL) and Low-LDL-C Group (LDL-C < 100 mg/dL) patients. Spearman correlation analysis of Lp(a), LDL-C and Gensini Score was performed in patients with different LDL-C concentration.

Results

Except male and diabetes, the traditional CAHD risk factors were well matched between two groups. But triglyceride, LDL-C and Lp(a) were higher, HDL-C and Apo-A1 were lower in CAHD group (2771). In the Logistic regression analysis, diabetes, LDL-C and Lp(a) are risk factors of CAHD in all patients, while in High-LDL-C Group, they were age, LDL-C, non-HDL-C and ApoB, in Low-LDL-C Group, they were age, Lp(a) and ApoB. Lp(a) correlated with Gensini with coefficient r = 0.41 in all patients, 0.67 in Low-LDL-C Group and 0.32 in High-LDL-C Group. The coefficient r for Lp(a) and Gensini decreased, while the r for LDL-C and Gensini increased with LDL-C concentration increasing. The two fitted lines of rs crossed at LDL-C = 2.7 mmol/L (104 mg/dL).

Conclusion

Lp(a) was the risk factor of CAHD in patients with LDL-C < 100 mg/dL. The correlation between Lp(a) and Gensini was influenced by LDL-C concentration, and the correlation was stronger than LDL-C when LDL-C < 104 mg/dl.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors in aortic stenosis - Is this the light at the end of the tunnel for patients with aortic stenosis?

The exploratory analysis of FOURIER trial has offered a ray of hope for patients with nonrheumatic aortic stenosis (AS). At present, the only definitive treatment of severe AS is aortic valve replacement (AVR). Despite transaortic valvular replacement revolutionizing the treatment of AS, it still remains a progressive condition, with no disease-modifying pharmacotherapy. Angiotensin-converting-enzyme inhibitors, angiotensin receptor blockers, eplerenone, nitrates and statins all have been tried previously but failed to slow down the progression of aortic stenosis. Recently, there has been an emerging role of lipoprotein A [Lp(a)] in the pathogenesis of AS. This raises the possibility that long-term therapy with specific emphasis on Lp(a) reduction may reduce or slow the progression of AS.

Lipoprotein(a): A Concealed Precursor of Increased Cardiovascular Risk? A Real-World Regional Lipid Clinic Experience

OBJECTIVE

Lipoprotein(a) [Lp(a)] is an independent cardiovascular risk factor. We present real-life characteristics of patients with increased Lp(a) levels attending a University Lipid Clinic.

METHODS

We retrospectively studied patients attending the University of Ioannina Hospital Lipid Clinic with Lp(a) levels ≥30 mg/dL who were followed-up for a median of 22 months.

RESULTS

One hundred eight patients (median age 59 years, 49% females) were included with median Lp(a) levels 67 mg/dL (30-320). Of patients, 25.1% had established atherosclerotic cardiovascular disease (ASCVD): 11.1 and 5.6% positive personal history of myocardial infarction (MI) and stroke, respectively, 6.5% carotid artery disease and 1.9% lower extremities arterial disease (LEAD). In addition, 35.2% of participants had heterozygous familial hypercholesterolemia (heFH), 37.9% positive family history of premature ASCVD, 29.6% hypertension, 12.0% diabetes and 5.5% chronic kidney disease (CKD). Of patients, 67.6% were receiving statin therapy and 16.6% additional ezetimibe at baseline visit, and 83 and 35% were receiving statin treatment and additional ezetimibe, respectively, during follow-up. Low-density cholesterol (LDL-C) levels and LDL-C_{corrected for Lp(a)} levels were significantly reduced in lipid-lowering therapy naive patients by 37 and 40% (p <0.05), in lipid-lowering therapy intensified patients by 31 and 36% (p <0.05), and in patients on stable lipid-lowering treatment by 15% (p <0.05) and 10% (p >0.05), respectively, during follow-up. Lp(a) levels increased by 9% (p <0.05).

CONCLUSION

Our data confirm the high prevalence of established ASCVD, hFH and positive familial history of premature ASCVD in patients with elevated Lp(a) levels. Lp(a) levels slightly increased during follow-up.

Elevated lipoprotein(a) and risk of coronary heart disease according to different lipid profiles in the general Chinese community population: the CHCN-BTH study

Background

To evaluate the contributions of elevated lipoprotein(a) [Lp(a)] to the risk of coronary heart disease (CHD) in the general Chinese community population according to different lipid profiles.

Methods

We recruited individuals aged over 18 years from the baseline survey of the Cohort Study on Chronic Disease of Communities Natural Population in Beijing, Tianjin and Hebei (CHCN-BTH) using a stratified, multistage cluster sampling method. Data were collected through questionnaire surveys, anthropometric measures and laboratory tests. Restricted cubic spline (RCS) functions, multivariate logistic regression, sensitivity analyses and stratified analyses were used to evaluate the association between Lp(a) and CHD.

Results

A total of 25,343 participants were included, with 1,364 (5.38%) identified as having CHD. Elevated Lp(a) levels were linearly related to an increased risk of CHD (P_{overall-association}<0.0001 and P_{nonlinear-association}=0.8468). Multivariate logistic regression analysis indicated that subjects with Lp(a) ≥300 mg/L had a higher risk of CHD [OR (95% CI): 1.36 (1.17, 1.57)] than did individuals with Lp(a) <300 mg/L. Compared with individuals with Lp(a) <119.0 mg/L (<50th percentile), the ORs (95% CI) for CHD in the 51st–80th, 81st–95th and >95th percentiles were 1.07 (0.93, 1.23), 1.26 (1.07, 1.50) and 1.68 (1.30, 2.17), respectively (P for trend <0.0001). This association was also found among the subgroup of subjects without dyslipidemia, including those with normal total cholesterol (TC) (<6.2 mmol/L), triglycerides (TG) (<2.3 mmol/L), high-density lipoprotein cholesterol (HDL-C) (≥1.0 mmol/L) and low-density lipoprotein cholesterol (LDL-C) (<4.1 mmol/L). Elevated Lp(a) and dyslipidemia significantly contributed to a higher risk of CHD with synergistic effects. Stratified analyses showed that elevated Lp(a) concentrations were significantly associated with an increased risk of CHD in the subgroups of individuals who were noncurrent drinkers, overweight individuals, individuals with hypertension, individuals who engaged in moderate physical activity, those without diabetes mellitus and individuals in Beijing and Tianjin.

Conclusions

Elevated Lp(a) concentrations were linearly associated with a higher risk of CHD in the general Chinese community population, especially in normolipidemic subjects. Both dyslipidemia and elevated Lp(a) independently or synergistically contributed to the risk of CHD. Our results suggest that more attention should be paid to the levels of Lp(a) in normolipidemic subjects, which may be an early predictor of CHD.

Lipoprotein (a): Recent Updates on a Unique Lipoprotein

PURPOSE OF REVIEW

Genetic, epidemiological, and translational data indicate that Lipoprotein (a) [Lp(a)] is likely in the causal pathway for atherosclerotic cardiovascular diseases as well as calcification of the aortic valves.

RECENT FINDINGS

Lp(a) is structurally similar to low-density lipoprotein, but in addition to apolipoprotein B-100, it has a glycoprotein apolipoprotein(a) [apo(a)], which is attached to the apolipoprotein B-100. Several distinctive properties of Lp(a) can be attributed to the presence of apo(a). This review discusses the current state of literature on pathophysiological and clinical aspects of Lp(a). After five decades of research, the understanding of Lp(a) structure, biochemistry, and pathophysiology of its cardiovascular manifestations still remains less than fully understood. Universally, Lp(a) elevation may be the most predominant monogenetic lipid disorder with approximate prevalence of Lp(a)>50 mg/dL among estimated >1.4 billion people. This makes a compelling rationale for diagnosing and managing Lp(a)-mediated risk. In addition to discussing various cardiovascular phenotypes of Lp(a) and associated morbidity, we also outline current and emerging therapies aimed at identifying a definitive treatment for elevated Lp(a) levels.

Subjects with familial hypercholesterolemia have lower aortic valve area and higher levels of inflammatory biomarkers

BACKGROUND

Reduction of the aortic valve area (AVA) may lead to aortic valve stenosis with considerable impact on morbidity and mortality if not identified and treated. Lipoprotein (a) [Lp(a)] and also inflammatory biomarkers, including platelet derived biomarkers, have been considered risk factor for aortic stenosis; however, the association between Lp(a), inflammatory biomarkers and AVA among patients with familial hypercholesterolemia (FH) is not clear.

OBJECTIVE

We aimed to investigate the relation between concentration of Lp(a), measurements of the aortic valve including velocities and valve area and circulating inflammatory biomarkers in adult FH subjects and controls.

METHODS

In this cross-sectional study aortic valve measures were examined by cardiac ultrasound and inflammatory markers were analyzed in non-fasting blood samples. The study participants were 64 FH subjects with high (n = 29) or low (n = 35) Lp(a), and 14 healthy controls.

RESULTS

Aortic valve peak velocity was higher (p = 0.02), and AVA was lower (p = 0.04) in the FH patients compared to controls; however, when performing multivariable linear regression, there were no significant differences. Furthermore, there were no significant differences between the high and low FH Lp(a) groups regarding the aortic valve. FH subjects had higher levels of platelet-derived markers CD40L, PF4, NAP2 and RANTES compared to controls (0.003 ≤ P ≤ 0.03). This result persisted after multiple linear regression.

CONCLUSIONS

Middle-aged, intensively treated FH subjects have higher aortic valve velocity, lower AVA, and higher levels of the platelet-derived markers CD40L, PF4, NAP2 and RANTES compared to healthy control subjects. The aortic valve findings were not significant after multiple linear regression, whereas the higher levels of platelet-derived markers were maintained.

Gender difference in lipoprotein(a) concentration as a predictor of coronary revascularization in patients with known coronary artery disease

BACKGROUND AND AIMS

Whether there is a gender difference in the impact of elevated plasma Lp(a) levels on recurrent coronary events remains unclear. We, therefore, evaluated the association between Lp(a) levels and the occurrence of major adverse coronary events in a large series of coronary patients (32% women).

METHODS

This single-center prospective cohort study investigated 3034 consecutive patients admitted to the Coronary Care Unit with a diagnosis of coronary ischemia. According to the inclusion criteria, 2374 patients completed the follow-up (mean of 2 years). The end-points were non-fatal myocardial infarction (MI), revascularization and coronary deaths.

RESULTS

Elevated Lp(a) levels were significantly associated with rate of revascularization, but not with non-fatal MI and cardiac death. According to Lp(a) stratification (≤30 mg/dl, >30-50 mg/dl and ≥50 mg/dl), there was a significant rise of revascularization events in the whole sample of participants, with a trend in hazard ratio (HR) of 1.23 (95% CI 1.04-1.46) and a 6% rise for every 10 mg/dl increment in Lp(a) levels. This effect was mainly driven by women (HR 2.04, 95%CI 1.33-3.12) who showed a 14% incremental risk for every 10 mg/dl rise in Lp(a) levels.

CONCLUSIONS

In patients with coronary artery disease, elevated plasma Lp(a) levels were found to be a potentially useful predictor of the need for coronary revascularizations, especially in women.

Lipoprotein(a) and Cardiovascular Disease Prevention across Diverse Populations

Lipoprotein(a) (Lp(a)) is a highly proatherogenic lipid fraction that is genetically determined and minimally responsive to lifestyle or behavior changes. Mendelian randomization studies have suggested a causal link between elevated Lp(a) and heart disease, stroke, and aortic stenosis. There is substantial inter-ethnic variation in Lp(a) levels, with persons of African descent having the highest median values. Monitoring of Lp(a) has historically been limited by lack of standardization of assays. With the advent of novel therapeutic modalities to lower Lp(a) levels including proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitors and targeted antisense oligonucleotides, it is increasingly important to screen patients who have family or personal history of atherosclerotic cardiovascular disease for elevations in Lp(a). Further study is needed to establish a causal relationship between elevated Lp(a) and cardiovascular disease across diverse ethnic populations.

Elevated levels of serum PCSK9 in male patients with symptomatic peripheral artery disease: The CAVASIC study

BACKGROUND AND AIMS

Peripheral artery disease (PAD) affects more than 200 million people worldwide. Increased low-density lipoprotein cholesterol (LDL-C)levels are a risk factor for PAD and the concentrations are influenced by proprotein convertase subtilisin/kexin type 9 (PCSK9). PCSK9 regulates the recycling of the LDL receptors to the cell membrane surface. Only a limited number of mostly small studies investigated the association between serum PCSK9 concentrations and PAD of different definition, which revealed contrasting results.

METHODS

Serum PCSK9, lipoprotein(a) [Lp(a)] and other lipoprotein concentrations were measured in male participants of the CAVASIC study, a case-control study of 248 patients with intermittent claudication and 251 age and diabetes-matched controls.

RESULTS

PAD patients had significantly higher PCSK9 concentrations when compared to controls (250 ± 77 vs. 222 ± 68 ng/mL, p < 0.001). Logistic regression analysis with adjustment for age revealed that an increase in PCSK9 concentrations of 100 ng/mL was associated with a 1.78-fold higher risk for PAD (95%CI 1.38-2.33, p = 1.43 × 10^-5). The association attenuated, but was still significant when adjusting additionally for age, Lp(a)-corrected LDL cholesterol, HDL cholesterol, high-sensitivity-CRP, statin treatment, hypertension, diabetes mellitus and smoking (OR = 1.49, 95%CI 1.03-2.18, p = 0.035). The strongest association was observed when both PCSK9 concentrations were above the median and Lp(a) concentrations were above 30 mg/dL (OR = 3.35, 95%CI 1.49-7.71, p = 0.0038).

CONCLUSIONS

Our findings suggest an association of higher PCSK9 concentrations with PAD, which was independent of other lipid parameters and classical cardiovascular risk factors.

Lipoprotein(a) and PCSK9 inhibition: clinical evidence

Compelling evidence has emerged from epidemiological and Mendelian randomization analyses relative to the causality of lipoprotein(a) [Lp(a)] in atherosclerotic cardiovascular diseases (ASCVD), being elevated Lp(a) a strong risk factor regardless of the reduction of LDL-C achieved by statins. So far, no specific available agent can lower Lp(a) to the extent required to achieve a cardiovascular (CV) benefit, i.e. approximately 100 mg/dL. The most recent outcomes trial FOURIER with evolocumab showed that a 25 nmol/L (12 mg/dL) reduction in Lp(a) corresponded to a 15% decrement in the relative risk of cardiovascular disease. The ODYSSEY OUTCOMES trial with alirocumab has been the first demonstrating that a reduction in Lp(a) associates with less major adverse cardiovascular events (MACE), i.e. hazard ratio: 0.994 per 1 mg/dL decrement in Lp(a). The Lp(a) lowering effect driven by PCSK9 inhibition was confirmed in carriers of PCSK9 loss-of-function mutations in which Lp(a) and oxPL-apoB levels were decreased compared to non-carriers as was for a slight larger number of apo(a) Kringle IV repeats. Although PCSK9 inhibitors are not able to decrease Lp(a) to the extent required to achieve a CV benefit, their use has led to a higher discontinuation rate in lipoprotein apheresis in patients with progressive ASCVD and high plasma Lp(a).

Persistent arterial wall inflammation in patients with elevated lipoprotein(a) despite strong low-density lipoprotein cholesterol reduction by proprotein convertase subtilisin/kexin type 9 antibody treatment

AIMS

Subjects with lipoprotein(a) [Lp(a)] elevation have increased arterial wall inflammation and cardiovascular risk. In patients at increased cardiovascular risk, arterial wall inflammation is reduced following lipid-lowering therapy by statin treatment or lipoprotein apheresis. However, it is unknown whether lipid-lowering treatment in elevated Lp(a) subjects alters arterial wall inflammation. We evaluated whether evolocumab, which lowers both low-density lipoprotein cholesterol (LDL-C) and Lp(a), attenuates arterial wall inflammation in patients with elevated Lp(a).

METHODS AND RESULTS

In this multicentre, randomized, double-blind, placebo-controlled study, 129 patients {median [interquartile range (IQR)]: age 60.0 [54.0-67.0] years, Lp(a) 200.0 [155.5-301.5] nmol/L [80.0 (62.5-121.0) mg/dL]; mean [standard deviation (SD)] LDL-C 3.7 [1.0] mmol/L [144.0 (39.7) mg/dL]; National Cholesterol Education Program high risk, 25.6%} were randomized to monthly subcutaneous evolocumab 420 mg or placebo. Compared with placebo, evolocumab reduced LDL-C by 60.7% [95% confidence interval (CI) 65.8-55.5] and Lp(a) by 13.9% (95% CI 19.3-8.5). Among evolocumab-treated patients, the Week 16 mean (SD) LDL-C level was 1.6 (0.7) mmol/L [60.1 (28.1) mg/dL], and the median (IQR) Lp(a) level was 188.0 (140.0-268.0) nmol/L [75.2 (56.0-107.2) mg/dL]. Arterial wall inflammation [most diseased segment target-to-background ratio (MDS TBR)] in the index vessel (left carotid, right carotid, or thoracic aorta) was assessed by 18F-fluoro-deoxyglucose positron-emission tomography/computed tomography. Week 16 index vessel MDS TBR was not significantly altered with evolocumab (-8.3%) vs. placebo (-5.3%) [treatment difference -3.0% (95% CI -7.4% to 1.4%); P = 0.18].

CONCLUSION

Evolocumab treatment in patients with median baseline Lp(a) 200.0 nmol/L led to a large reduction in LDL-C and a small reduction in Lp(a), resulting in persistent elevated Lp(a) levels. The latter may have contributed to the unaltered arterial wall inflammation.

Lipoprotein(a) in Patients With Type 2 Diabetes and Premature Coronary Artery Disease in the Coronary Care Unit

INTRODUCTION

Lipoprotein(a) [Lp(a)] and diabetes are independently associated with premature coronary artery disease (pCAD). However, there is an inverse relationship between Lp(a) concentration and type 2 diabetes (T2D) risk. We examine whether Lp(a) distribution in patients with pCAD differs between those with or without T2D, and whether elevated Lp(a) is associated with pCAD in patients with T2D.

METHODS

Lp(a) concentration was measured in consecutive acute coronary syndrome (ACS) patients in two coronary care units (study one: ACS with or without diabetes, study two: ACS and diabetes). Elevated Lp(a) mass concentration was defined as ≥0.5 g/L and pCAD where CAD was diagnosed age <60 years. The association between elevated Lp(a) and pCAD was assessed using logistic regression.

RESULTS

Of 449 patients, 233 (51.9%) had pCAD and 278 (61.9%) had T2D. In patients with pCAD, those with T2D had a significantly lower median Lp(a) concentration (0.13 g/L versus 0.27 g/L, p=0.004). In patients with T2D, elevated Lp(a) was significantly associated with pCAD (OR 2.419, 95% CI 1.513-3.867, p<0.001). After adjusting for gender, smoking, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides, elevated Lp(a) remained significantly associated with pCAD (OR 2.895, 95% CI 1.427-5.876, p=0.003) in patients with T2D.

CONCLUSIONS

In coronary care patients with pCAD, patients with T2D had lower Lp(a) concentrations than those without T2D. Despite this, elevated Lp(a) remained predictive of pCAD in patients with T2D. Measurement of Lp(a) should be considered in younger adults with T2D to identify who may benefit from earlier preventative therapies to reduce pCAD burden.

Effect of different types and dosages of statins on plasma lipoprotein(a) levels: A network meta-analysis

BACKGROUND AND AIM

Studies differ with respect to the effects of statins and their on lipoprotein(a)[Lp(a)] levels. The aim of the present study was to resolve these differences by determining the effect of various types and dosages of statins on Lp(a) levels.

METHODS

We searched PubMed, Embase and the Cochrane library for randomized controlled trials (RCTs) investigating the efficacy of statins on plasma Lp(a) levels. Study selection, data extraction and risk of bias assessment were conducted independently by four authors. We conducted pairwise meta-analysis and network meta-analysis (NMA). Consistency models were applied to NMA and the ranking probabilities for each treatment's efficacy were calculated. Node-splitting analysis was used to test inconsistency. This study was registered with PROSPERO, number CRD42020167612.

RESULTS

Twenty RCTs with 23,605 participants were included, involving 11 interventions. Most of the included studies presented some risks of bias, especially risks of performance and detection bias. In the pairwise meta-analysis, pooled results showed a small but statistically significant difference between high-intensity rosuvastatin and placebo on Lp(a) levels (MD = 1.81, 95 % CI [0.43, 3.19], P = 0.01). In the NMA, different types and dosages of statins showed no significant effect on the level of Lp(a), and there was no obvious difference between them. Subgroup analysis based on different populations and treatment durations did not provide any statistically significant findings about different statins on Lp(a) levels. Node-splitting analysis showed that no significant inconsistency existed (P > 0.05).

CONCLUSIONS

Statins have no clinically significant effect on Lp(a) levels, and there is no significant difference in the effect on Lp(a) levels between different types and dosages of statins. Moderate-intensity pitavastatin tended to have the best effect on reducing Lp(a) levels; nevertheless, it was insignificant. Our findings highlight the necessity for further study of the effect of statins on Lp(a) levels in future studies.

The role of Lipoprotein(a) in cardiovascular disease: Current concepts and future perspectives

High lipoprotein(a) [Lp(a)] levels are associated with the development of atherosclerotic cardiovascular disease (ASCVD) and with calcific aortic valve stenosis (CAVS) both observationally and causally from human genetic studies. The mechanisms are not well characterized but likely involve its role as a carrier of oxidized phospholipids (OxPLs), which are known to be increased in pro-inflammatory states, to induce pro-inflammatory changes in monocytes leading to plaque instability, and to impair vascular endothelial cell function, a driver of acute and recurrent ischemic events. In addition, Lp(a) itself has prothrombotic activity. Current lipid-lowering strategies do not sufficiently lower Lp(a) serum levels. Lp(a)-specific-lowering drugs, targeting apolipoprotein(a) synthesis, lower Lp(a) by up to 90% and are being evaluated in ongoing clinical outcome trials. This review summarizes the current knowledge on the associations of Lp(a) with ASCVD and CAVS, the current role of Lp(a) assessment in the clinical setting, and emerging Lp(a)-specific-lowering therapies.

Lipoprotein(a) and cardiovascular disease: prediction, attributable risk fraction, and estimating benefits from novel interventions

AIMS 

To investigate the population attributable fraction due to elevated lipoprotein (a) (Lp(a)) and the utility of measuring Lp(a) in cardiovascular disease (CVD) risk prediction.

METHODS AND RESULTS 

In 413 734 participants from UK Biobank, associations of serum Lp(a) with composite fatal/non-fatal CVD (n = 10 066 events), fatal CVD (n = 3247), coronary heart disease (CHD; n = 18 292), peripheral vascular disease (PVD; n = 2716), and aortic stenosis (n = 901) were compared using Cox models. Median Lp(a) was 19.7 nmol/L (interquartile interval 7.6-75.3 nmol/L). About 20.8% had Lp(a) values >100 nmol/L; 9.2% had values >175 nmol/L. After adjustment for classical risk factors, 1 SD increment in log Lp(a) was associated with a hazard ratio for fatal/non-fatal CVD of 1.12 [95% confidence interval (CI) 1.10-1.15]. Similar associations were observed with fatal CVD, CHD, PVD, and aortic stenosis. Adding Lp(a) to a prediction model containing traditional CVD risk factors in a primary prevention group improved the C-index by +0.0017 (95% CI 0.0008-0.0026). In the whole cohort, Lp(a) above 100 nmol/L was associated with a population attributable fraction (PAF) of 5.8% (95% CI 4.9-6.7%), and for Lp(a) above 175 nmol/L the PAF was 3.0% (2.4-3.6%). Assuming causality and an achieved Lp(a) reduction of 80%, an ongoing trial to lower Lp(a) in patients with CVD and Lp(a) above 175 nmol/L may reduce CVD risk by 20.0% and CHD by 24.4%. Similar benefits were also modelled in the whole cohort, regardless of baseline CVD.

CONCLUSION 

Population screening for elevated Lp(a) may help to predict CVD and target Lp(a) lowering drugs, if such drugs prove efficacious, to those with markedly elevated levels.

Genetic and nutritional factors determining circulating levels of lipoprotein(a): results of the "Montignoso Study"

Increasing evidence shows an association between high lipoprotein(a) [Lp(a)] levels and atherothrombotic diseases. Lp(a) trait is largely controlled by kringle-IV type 2 (KIV-2) size polymorphism in LPA gene, encoding for apo(a). Environmental factors are considered to determinate minor phenotypic variability in Lp(a) levels. In the present study, we investigated the possible gene-environment interaction between KIV-2 polymorphism and Mediterranean diet adherence or fish weekly intake in determining Lp(a) levels. We evaluated Lp(a), KIV-2 polymorphism, fish intake and Mediterranean diet adherence in 452 subjects [median age (range) 66 (46-80)years] from Montignoso Heart and Lung Project (MEHLP) population. In subjects with high KIV-2 repeats number, influence of Mediterranean diet adherence in reducing Lp(a) levels was observed (p = 0.049). No significant difference in subjects with low KIV-2 repeats according to diet was found. Moreover, in high-KIV-2-repeat subjects, we observed a trend towards influence of fish intake on reducing Lp(a) levels (p = 0.186). At multivariate linear regression analysis, high adherence to Mediterranean diet remains a significant and independent determinant of lower Lp(a) levels (β = - 64.97, standard error = 26.55, p = 0.015). In conclusion, this study showed that only subjects with high KIV-2 repeats can take advantage to lower Lp(a) levels from correct nutritional habits and, in particular, from Mediterranean diet.

Measuring the contribution of Lp(a) cholesterol towards LDL-C interpretation

BACKGROUND

Lipoprotein(a) [Lp(a)] is a pro-atherogenic and pro-thrombotic LDL-like particle recognized as an independent risk factor for cardiovascular disease (CVD). The cholesterol within Lp(a) (Lp(a)-C) contributes to the reported LDL-cholesterol (LDL-C) concentration by nearly all available methods. Accurate LDL-C measurements are critical for identification of genetic dyslipidemias such as familial hypercholesterolemia (FH). FH diagnostic criteria, such as the Dutch Lipid Clinic Network (DLCN) criteria, utilize LDL-C concentration cut-offs to assess the likelihood of FH. Therefore, failure to adjust for Lp(a)-C can impact accurate FH diagnosis and classification, appropriate follow-up testing and treatments, and interpretation of cholesterol-lowering treatment efficacy.

OBJECTIVE

In this study, we use direct Lp(a)-C measurements to assess the potential misclassification of FH from contributions of Lp(a)-C to reported LDL-C in patient samples submitted for advanced lipoprotein profiling.

METHODS

A total of 31,215 samples submitted for lipoprotein profiling were included. LDL-C was measured by beta quantification or calculated by one of three equations. Lp(a)-C was measured by quantitative lipoprotein electrophoresis. DLCN LDL-C cut-offs were applied to LDL-C results before and after accounting for Lp(a)-C contribution.

RESULTS

Lp(a)-C was detected in 8665 (28%) samples. A total of 940 subjects were reclassified to a lower DLCN LDL-C categories; this represents 3% of the total patient series or 11% of subjects with measurable Lp(a)-C.

CONCLUSION

Lp(a)-C is present in a significant portion of samples submitted for advanced lipid testing and could cause patient misclassification when using FH diagnostic criteria. These misclassifications could trigger inappropriate follow-up, treatment, and cascade testing for suspected FH.

Lipoprotein(a) and cardiovascular death in oldest-old (≥80 years) patients with acute myocardial infarction: A prospective cohort study

BACKGROUND AND AIMS

Compared with what is known about the prognostic value of lipoprotein(a) [Lp(a)] in middle-aged patients with atherosclerotic cardiovascular disease (ASCVD), less is understood concerning the role of Lp(a) in oldest-old (≥80 years old) with ASCVD. The aim of the present study was to investigate the relationship between Lp(a) and cardiovascular death (CD) among the oldest-old with acute myocardial infarction (AMI).

METHODS

A total of 1008 patients with AMI, older than 80 years, were consecutively enrolled between January 2012 and August 2018. The clinical characteristics were collected and Lp(a) concentrations were measured by the immunoturbidimetric method at baseline. The relationship between plasma Lp(a) concentration (≤10 mg/dL, 10-30 mg/dL, >30 mg/dL) and CD was evaluated by Kaplan-Meier analysis and Cox proportional hazard models.

RESULTS

During an average of 36.26 months of follow-up, 287 CD occurred. Data showed that patients with high Lp(a) levels (>30 mg/dL) had the highest rate of CD (p < 0.05). Kaplan-Meier analysis showed that the high Lp(a) group had the lowest event-free survival rate in the oldest-old with AMI (p = 0.030). In addition, subjects with Lp(a) > 30 mg/dL had a 1.5-fold (95% confidence interval: 1.083-2.132) higher risk of CD compared with those with Lp(a) ≤10 mg/dL in fully adjusted Cox proportional hazards model.

CONCLUSIONS

The current data firstly showed that plasma Lp(a) concentration was associated with the risk of CD in oldest-old with AMI, suggesting that Lp(a) could be a useful adjunctive measurement in the evaluation of CD in this population.

Lipoprotein(a) levels and risk of abdominal aortic aneurysm in the Women's Health Initiative

OBJECTIVE

Few studies have prospectively examined the associations of lipoprotein(a) [Lp(a)] levels with the risk of abdominal aortic aneurysm (AAA), especially in women. Accounting for commonly recognized risk factors, we investigated the baseline Lp(a) levels and the risk of AAA among postmenopausal women participating in the ongoing national Women's Health Initiative.

METHODS

Women's Health Initiative participants with baseline Lp(a) levels available who were beneficiaries of Medicare parts A and B fee-for-service at study enrollment or who had aged into Medicare at any point were included. Participants with missing covariate data or known AAA at baseline were excluded. Thoracic aneurysms were excluded owing to the different pathophysiology. The AAA cases and interventions were identified using the International Classification of Diseases, 9th and 10th revision, codes and Current Procedural Terminology codes from claims data. Hazard ratios were computed using Cox proportional hazard models according to the quintiles of Lp(a).

RESULTS

The mean age of the 6615 participants included in the analysis was 65.3 years. Of the 6615 participants, 66.6% were non-Hispanic white, 18.9% were black, 7% were Hispanic and 4.7% were Asian/Pacific Islander. Compared with the participants in the lowest Lp(a) quintile, those in higher quintiles were more likely to be overweight, black, and former or current smokers, to have hypertension, hyperlipidemia, and a history of cardiovascular disease, and to use menopausal hormone therapy and statins. During 65,476 person-years of follow-up, with a median of 10.4 years, 415 women had been diagnosed with an AAA and 36 had required intervention. More than one half had required intervention for a ruptured AAA. We failed to find a statistically significant association between Lp(a) levels and incident AAA. Additional sensitivity analyses stratified by race, with exclusion of statin users and alternative categorizations of Lp(a) using log-transformed levels, tertiles, and a cutoff of >50 mg/dL, were conducted, which did not reveal any significant associations.

CONCLUSIONS

We found no statistically significant association between Lp(a) levels and the risk of AAA in a large and well-phenotyped sample of postmenopausal women. Women with high Lp(a) levels were more likely to be overweight, black, and former or current smokers, and to have hypertension, hyperlipidemia, and a history of cardiovascular disease, or to use hormone therapy and statins compared with those with lower Lp(a) levels. These findings differ from previous prospective, case-control, and meta-analysis studies that had supported a significant relationship between higher Lp(a) levels and an increased risk of AAA. Differences in the association could have resulted from study limitations or sex differences.

Relationship Between Lipoprotein(a) and Angiographic Severity of Femoropopliteal Lesions

AIM

High levels of lipoprotein(a) [Lp(a)] are a risk factor for peripheral artery disease (PAD). However, the relationship between Lp(a) levels and the severity of femoropopliteal lesions in patients with PAD has not been systematically studied. This study aimed to assess the impact of Lp(a) levels on angiographic severity of femoropopliteal lesions in patients with PAD.

METHODS

We retrospectively analyzed a single-center database including 108 patients who underwent endovascular therapy for de novo femoropopliteal lesions and measured the Lp(a) levels before therapy between June 2016 and September 2019. Patients were divided into low Lp(a) [Lp(a) ＜30 mg/dL; 77 patients] and high Lp(a) [Lp(a) ≥ 30 mg/dL; 31 patients] groups. Trans-Atlantic Inter-Society Consensus (TASC) II classification, calcification [referring to the peripheral arterial calcium scoring system (PACSS) classification], and lesion length were compared between the groups.

RESULTS

The prevalence of TASC II class D (13% vs 38%, P＜0.01) and severe calcification (PACSS 4) (6% vs 23%, P=0.02) was significantly higher and the lesion length longer (123±88 mm vs 175±102 mm, P＜0.01) in the high Lp(a) group than in the low Lp(a) group. In multivariate analysis, Lp(a) ≥ 30 was an independent predictor for the prevalence of TASC II class D (HR=3.67, 95% CI 1.27-10.6, P=0.02) and PACSS 4 (HR=4.97, 95% CI 1.27-19.4, P=0.02).

CONCLUSION

The prevalence of TASC II class D and severe calcification of femoropopliteal lesions was higher in patients with high Lp(a) than those with low Lp(a).

Association of lipoprotein(a) with platelet aggregation and thrombogenicity in patients undergoing percutaneous coronary intervention

This study aimed to evaluate the association of lipoprotein(a) levels with platelet aggregation and thrombogenicity in patients undergoing percutaneous coronary intervention (PCI), and to investigate the ischemic outcome on this population. Lipoprotein(a) and modified thrombelastography were measured in 6601 consecutive patients underwent PCI on dual antiplatelet therapy. Cox proportional regression analysis was applied to illustrate the ischemic events in a 2-year follow up. The mean levels of lipoprotein(a) were 29.0 mg/dl. Patients with higher lipoprotein(a) levels had significantly accelerated fibrin generation (lower K time and bigger α angle) and greater clot strength (higher maximum amplitude (MA)) than patients with lower lipoprotein(a) levels (P < .001). Moreover, the higher lipoprotein(a) group also exhibited significantly higher adenosine diphosphate (ADP) induced platelet aggregation (MA_ADP) by thrombelastography platelet mapping assay than lower lipoprotein(a) group. Cox regression analyzes revealed that patients with higher lipoprotein(a) levels had a 16% higher risk of major adverse cardiovascular and cerebrovascular events (HR 1.159, 95%CI: 1.005-1.337, P = .042) compared with patients with lower lipoprotein(a) levels. This association persisted after adjustment for a broad spectrum of risk factors (HR 1.174, 95%CI: 1.017-1.355, P = .028). High plasma lipoprotein(a) levels were associated with increased platelet aggregation and ischemic events in patients underwent PCI. Lipoprotein(a) might indicate the need for prolonged antiplatelet therapy.

Lipoprotein(a) in atherosclerosis: from pathophysiology to clinical relevance and treatment options

Lipoprotein(a) (Lp(a)) was discovered more than 50 years ago, and a decade later, it was recognized as a risk factor for coronary artery disease. However, it has gained importance only in the past 10 years, with emergence of drugs that can effectively decrease its levels. Lp(a) is a low-density lipoprotein (LDL) with an added apolipoprotein(a) attached to the apolipoprotein B component via a disulphide bond. Circulating levels of Lp(a) are mainly genetically determined. Lp(a) has many functions, which include proatherosclerotic, prothrombotic and pro-inflammatory roles. Here, we review recent data on the role of Lp(a) in the atherosclerotic process, and treatment options for patients with cardiovascular diseases. Currently 'Proprotein convertase subtilisin/kexin type 9' (PCSK9) inhibitors that act through non-specific reduction of Lp(a) are the only drugs that have shown effectiveness in clinical trials, to provide reductions in cardiovascular morbidity and mortality. The effects of PCSK9 inhibitors are not purely through Lp(a) reduction, but also through LDL cholesterol reduction. Finally, we discuss new drugs on the horizon, and gene-based therapies that affect transcription and translation of apolipoprotein(a) mRNA. Clinical trials in patients with high Lp(a) and low LDL cholesterol might tell us whether Lp(a) lowering per se decreases cardiovascular morbidity and mortality.KEY MESSAGESLipoprotein(a) is an important risk factor in patients with cardiovascular diseases.Lipoprotein(a) has many functions, which include proatherosclerotic, prothrombotic and pro-inflammatory roles.Treatment options to lower lipoprotein(a) levels are currently scarce, but new drugs are on the horizon.

Serum lipoprotein(a) levels and insulin resistance have opposite effects on fatty liver disease

BACKGROUND AND AIMS

High lipoprotein(a) [Lp(a)] levels are associated with increased risk of cardiovascular disease. However, the association between Lp(a) and fatty liver disease (FLD) remains controversial. Therefore, we analyzed the relationship between FLD and serum Lp(a) levels in Korean adults.

METHODS

A total of 22,534 participants who underwent a routine health screening program at Kangbuk Samsung Hospital in 2010 and 2014 were enrolled. Anthropometric and biochemical parameters, including Lp(a), were measured. The presence of FLD was assessed using abdominal ultrasonography. Odds ratios (ORs) for the presence of FLD were analyzed in quartile groups of serum Lp(a) levels using logistic regression. We divided the participants into four groups according to the median values of Lp(a) and homeostasis model assessment for insulin resistance (HOMA-IR).

RESULTS

Among the total study population, 3030 (13.4%) participants had fatty liver disease. The mean Lp(a) level was lower in subjects with FLD than in those without (70.0 vs 73.8 nmol/L, p < 0.001). The OR for FLD was the lowest in the fourth Lp(a) quartile group, using the first quartile group as the reference group after adjusting for confounding factors [0.815; 95% confidence interval (CI) 0.725-0.916]. When the OR for FLD was analyzed in four groups divided by the median values of Lp(a) and HOMA-IR, the low Lp(a)-high HOMA-IR group had the greatest OR for FLD, using the high Lp(a)-low HOMA-IR group as the reference (1.903; 95% CI 1.679-2.158).

CONCLUSIONS

Serum Lp(a) levels were inversely associated with the presence of FLD. Subjects with low Lp(a) and high insulin resistance (IR) showed higher risk of FLD than those with high Lp(a) and low IR, suggesting the opposite associations of Lp(a) and IR with FLD.

Lipoprotein(a) and Its Potential Association with Thrombosis and Inflammation in COVID-19: a Testable Hypothesis

PURPOSE OF REVIEW

The COVID-19 pandemic has infected over > 11 million as of today people worldwide and is associated with significant cardiovascular manifestations, particularly in subjects with preexisting comorbidities and cardiovascular risk factors. Recently, a predisposition for arterial and venous thromboses has been reported in COVID-19 infection. We hypothesize that besides conventional risk factors, subjects with elevated lipoprotein(a) (Lp(a)) may have a particularly high risk of developing cardiovascular complications.

RECENT FINDINGS

The Lp(a) molecule has the propensity for inhibiting endogenous fibrinolysis through its apolipoprotein(a) component and for enhancing proinflammatory effects such as through its content of oxidized phospholipids. The LPA gene contains an interleukin-6 (IL-6) response element that may induce an acute phase-type increase in Lp(a) levels following a cytokine storm from COVID-19. Thus, subjects with either baseline elevated Lp(a) or those who have an increase following COVID-19 infection, or both, may be at very high risk of developing thromboses. Elevated Lp(a) may also lead to acute destabilization of preexisting but quiescent atherosclerotic plaques, which might induce acute myocardial infarction and stroke. Ongoing studies with IL-6 antagonists may be informative in understanding this relationship, and registries are being initiated to measure Lp(a) in subjects infected with COVID-19. If indeed an association is suggestive of being causal, consideration can be given to systematic testing of Lp(a) and prophylactic systemic anticoagulation in infected inpatients. Therapeutic lipid apheresis and pharmacotherapy for the reduction of Lp(a) levels may minimize thrombogenic potential and proinflammatory effects. We propose studies to test the hypothesis that Lp(a) may contribute to cardiovascular complications of COVID-19.

Coronary artery disease and the risk-associated LPA variants, rs3798220 and rs10455872, in patients with suspected familial hypercholesterolaemia

BACKGROUND

The rs3798220 and rs10455872 single nucleotide polymorphisms (SNPs) in LPA are associated with increased plasma concentrations of lipoprotein(a) [Lp(a)] and coronary artery disease (CAD).

METHODS

We investigated the association between rs3798220 and rs10455872 and prevalent CAD in 763 patients with suspected familial hypercholesterolaemia (FH). The rs3798220 and rs10455872 SNPs in LPA were detected using a SEQUENOM platform.

RESULTS

Both LPA SNPs were significantly associated with CAD, but only rs3798220 after adjustment for other risk factors (odds ratio [OR] 2.05; 95% confidence interval [CI] 1.02-4.12; p = 0.045), and neither after adjustment for Lp(a) concentrations. Both SNPs were positively and independently associated with increased Lp(a) (rs3798220: OR 1.27; 95% CI 0.96-1.57; p < 0.001. rs10455872: OR 1.41; 95% CI 1.24-1.58; p < 0.001). Plasma concentrations of Lp(a) were independently associated with prevalent CAD (OR 1.28; 95% CI 1.08-1.52, p = 0.005) after adjustment for LPA SNPs and other cardiovascular risk factors. While both the rs3798220 and rs10455872 SNPs were associated with Lp(a) concentrations and prevalent CAD in patients with suspected FH, this was not independent of Lp(a) concentration.

CONCLUSIONS

Quantification of Lp(a) is more likely to be useful than assessment of these Lp(a)-associated SNPs to augment CAD risk prediction.

Why Some Patients Undergoing Lipoprotein Apheresis Therapy Develop New Cardiovascular Events?

Lipoprotein apheresis (LA) is an effective tool to reduce cardiovascular events (CVEs) in high-risk patients with elevations of low density lipoprotein-cholesterol (LDL-C) and/or Lipoprotein(a) (Lp(a)). All patients included into this retrospective analysis had experienced CVEs before the start of the LA therapy. We compared personal and lab data in two groups: CVEx/0 (n 60) with no new events during LA therapy, CVEx/1+ (n 48) with at least one new event. Patients of Group CVEx/1+ were about 5 years older when they had started the extracorporeal therapy, and they experienced more CVEs prior to that timepoint. There was a positive correlation between the number of CVEs before and during LA therapy. No differences were seen with respect to lipid concentrations, even after a correction of LDL-C concentrations for the LDL-C transported with Lp(a) particles. LA sessions effectively reduced both LDL-C and Lp(a). Lp(a) levels measured before LA sessions were lower than those measured initially. It appeared difficult to reach the target values for LDL-C published in the ESC/EAS Guideline in 2019, although all patients were maximally treated including drugs when tolerated. In conclusion, it will be important to initiate an LA therapy earlier, at least after a second CVE and at a younger age.

Acute and Chronic Impact of Biliopancreatic Diversion with Duodenal Switch Surgery on Plasma Lipoprotein(a) Levels in Patients with Severe Obesity

BACKGROUND

Elevated lipoprotein(a) (Lp(a)) level is an independent risk factor for cardiovascular diseases. Lifestyle intervention studies targeting weight loss revealed little to no significant changes in Lp(a) levels. The impact of interventions that induce substantial weight loss, such as bariatric surgery, on Lp(a) levels is currently unclear.

OBJECTIVE

To determine the acute and long-term impact of bariatric surgery on Lp(a) levels in patients with severe obesity.

METHODS

Sixty-nine patients with severe obesity underwent biliopancreatic diversion with duodenal switch (BPD-DS) surgery. The lipid profile was evaluated and Lp(a) levels were measured before surgery and at 6 and 12 months after BPD-DS surgery.

RESULTS

Median Lp(a) levels at baseline were 11.1 (4.1-41.6) nmol/L. Six months and 12 months after the BDP-DS surgery, we observed an improvement of lipid profile. At 6 months, we observed a 13% decrease in Lp(a) levels (9.7 (2.9-25.6) nmol/L, p < 0.0001) but this decrease was not sustained at 12 months (11.1 (3.9-32.8) nmol/L, p = 0.8). When the patients were separated into tertiles according to Lp(a) levels at baseline, we observed that the Lp(a) reduction at 12 months after BPD-DS surgery remained significant but modest in patients of the top Lp(a) tertile.

CONCLUSION

Our results suggest that BPD-DS surgery modestly reduces Lp(a) levels in the short term (6 months) in patients with severe obesity but this improvement is sustained over time only in patients with higher Lp(a) levels.

Serum Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) is Independently Associated with Insulin Resistance, Triglycerides, Lipoprotein(a) Levels but not Low-Density Lipoprotein Cholesterol Levels in a General Population

Aim: Proprotein convertase subtilisin/kexin type 9 (PCSK9) has been identified as an important regulator of low-density lipoprotein (LDL) receptor processing. Evolocumab and alirocumab are PCSK9 inhibitors; however, little is known about the association between PCSK9 levels and lipid profiles in a general population. Because PCSK9 inhibitors have LDL-C lowering effects, we investigated whether there is a positive correlation between serum PCSK9 levels and LDL-C or lipoprotein(a) [Lp(a)].

Methods: In Uku town, 674 residents (mean age; 69.2 ± 8.3 years) received health check-ups. The participants underwent a physical examination and blood tests, including PCSK9 and Lp(a). Serum PCSK9 and Lp(a) were measured by ELISA and Latex methods, respectively. HOMA-IR was calculated by fasting plasma glucose × insulin levels/405.

Results: The mean (range) of PCSK9 and Lp(a) were 211.2 (49–601) ng/mL and 60 (1–107) mg/dL, respectively. Because of a skewed distribution, the log-transformed values were used. With univariate linear regression analysis, PCSK9 levels were associated with Lp(a) (p = 0.028), triglycerides (p < 0.001), and HOMA-IR (p < 0.001), but not with LDL-C (p = 0.138) levels. Multiple stepwise regression analysis revealed that serum PCSK9 levels were independently associated with triglycerides (p < 0.001), Lp(a) (p = 0.033) and HOMA-IR (p = 0.041).

Conclusions: PCSK-9 is independently associated with triglycerides, Lp(a) levels, and HOMA-IR, but not LDL-C, in a relatively large general population sample.

Lipoprotein(a) concentration is associated with risk of type 2 diabetes and cardiovascular events in a Chinese population with very high cardiovascular risk

PURPOSE

Evidences have shown that elevated lipoprotein(a) [Lp(a)] levels were associated with a lower risk of type 2 diabetes, but a higher risk of cardiovascular events in general populations. We aim to demonstrate the effect of Lp(a) concentrations on type 2 diabetes and cardiovascular events in a Chinese population with very high cardiovascular risk.

METHODS

Seven hundred ninety-eight participants who underwent coronary angiography between March and November 2013 with normal glucose metabolism were followed up from July to December 2018.

RESULTS

Five hundred thirty-five participants completed follow-up, and 395 of them had blood glucose data. Among 395 participants with blood glucose data, a total of 28 incident type 2 diabetes were identified during a median follow-up period of 4.42 years. Compared with the patients in the lowest tertile of Lp(a), the multifactorial adjusted HR for type 2 diabetes was 0.29 in the highest tertile (95% confidence intervals (CI) 0.10-0.89; P for trend = 0.03). Among 535 patients who completed follow-up, a total of 80 cases of major adverse cardiovascular events (MACE) were identified during a median follow-up period of 5.08 years. Compared with the patients in the lowest tertile of Lp(a), the multifactorial adjusted HR for MACE was 1.95 in the highest tertile (95% CI 1.05-3.65; P for trend = 0.03).

CONCLUSIONS

Elevated Lp(a) levels were associated with a lower risk of type 2 diabetes, but a higher risk of cardiovascular events in a Chinese population with very high cardiovascular risk.

Lipoprotein(a)and renal function decline, cardiovascular disease and mortality in type 2 diabetes and microalbuminuria

AIMS

Lipoprotein(a)(Lp(a)) has emerged as an independent risk marker for cardiovascular disease (CVD) in the general population and among persons with existing CVD. We investigated associations between serum Lp(a)concentrations and renal function decline, incident CVD and all-cause mortality in individuals with type 2 diabetes (T2D) and microalbuminuria.

METHODS

Prospective study including 198 individuals with T2D, microalbuminuria and no CVD. Yearly p-creatinine was measured after baseline in 176 of the participants. The renal endpoint was defined as decline in eGFR of >30% from baseline. CVD events and mortality were tracked from national registries. Cox regression analyses were applied both unadjusted and adjusted for traditional risk factors (sex, age, systolic blood pressure, LDL-cholesterol, smoking, HbA_1c, creatinine and urinary albumin creatinine ratio (UAER)).

RESULTS

Baseline mean (SD) age was 59 (9)years, eGFR 89 (17) mL/min/1.73 m², 77% were male, and median [IQR] UAER was 103 [38-242] mg/24-h. Median Lp(a)was 8.04 [3.42-32.3] mg/dL. Median follow-up was 6.1 years; 38 CVD events, 26 deaths and 43 renal events were recorded. For each doubling of baseline Lp(a), the following hazard ratios (95% confidence intervals) were found before and after adjustment respectively: 0.98 (0.84-1.15) and 1.01 (0.87-1.18) for decline in eGFR > 30%, 0.96 (0.81-1.13) and 0.99 (0.82-1.18) for CVD events, 1.04 (0.85-1.27) and 1.06 (0.87-1.30) for all-cause mortality.

CONCLUSIONS

In this cohort of individuals with T2D and microalbuminuria, the baseline concentration of Lp(a)was not a risk marker for renal function decline, CVD events or all-cause mortality.