Current opinion in lipidology最新文献

Purpose of review: The aim of this study was to discuss the potential mechanisms and implications of the opposing liver safety results from recent angiopoietin-like 3 (ANGPTL3) inhibition studies.

Recent findings: The clinical development of vupanorsen, a N-acetylgalactosamine (GalNAc) antisense targeting hepatic ANGPTL3, was recently discontinued due to a significant signal of liver transaminase increase. Vupanorsen elicited a dose-dependent increase in hepatic fat fraction up to 75%, whereas the small interfering RNA (siRNA) ARO-ANG3, has reported preliminary evidence of a dose-dependent decrease in hepatic fat fraction up to 30%.

Summary: ANGPTL3 inhibition is an attractive therapeutic target to reduce all apoB-containing lipoproteins. The discrepancy in liver signal results between the antisense and siRNA approach may be explained by the level of target inhibition. An alternative explanation may relate to off-target effects of vupanorsen, which have a molecule- and/or platform-specific origin. For intrahepatic strategies, highly potent ANGPTL3 inhibition will for now require special attention for liver safety.

Purpose of review: Familial hypercholesterolemia is associated with an increased risk of cardiovascular disease. The current international guidelines of the main scientific societies consider that, all people with Familial Hypercholesterolemia have a high or very high cardiovascular risk. However, the occurrence of atherosclerotic cardiovascular disease is very heterogeneous in this population. Stratifying risk within people with familial hypercholesterolemia is essential to identify individuals who require intensive cholesterol-lowering therapies.

Recent findings: In the last year, several studies have been published focusing on the contribution of diabetes to Familial Hypercholesterolemia, the role of stroke, as a manifestation of atherosclerotic disease, and the external validation of the SAFEHEART risk equation in the English population diagnosed with Familial Hypercholesterolemia.

Summary: It is necessary the development of a tool that allows us to identify, in a simple, reproducible, and universal way, patients who may have a high risk of suffering a cardiovascular event and who are susceptible to more intensive treatments to reduce cholesterol levels.

Purpose of review: Metabolism of lipids and lipoproteins, including high-density lipoprotein (HDL), plays a central role in energy homeostasis. Mechanisms underlying the relationship between energy homeostasis and HDL however remain poorly studied.

Recent findings: Available evidence reveals that HDL is implicated in energy homeostasis. Circulating high-density lipoprotein-cholesterol (HDL-C) levels are affected by energy production, raising with increasing resting metabolic rate. Lipolysis of triglycerides as a source of energy decreases plasma levels of remnant cholesterol, increases levels of HDL-C, and can be cardioprotective. Switch to preferential energy production from carbohydrates exerts opposite effects.

Summary: Low HDL-C may represent a biomarker of inefficient energy production from fats. HDL-C-raising can be beneficial when it reflects enhanced energy production from burning fat.

Purpose of review: Lowering LDL-C has been shown to reduce ASCVD events, yet many ASCVD patients do not achieve their guideline-directed LDL-C goals leaving patients at increased risk of another ASCVD event. This review discusses implementation strategies to improve guideline-directed lipid management in patients with ASCVD focusing on the provider, patient, and system level.

Recent findings: At a provider level, under-prescribing of statin intensity due most often to statin intolerance, clinical inertia, insufficient monitoring of LDL-C levels, and the difficulty and cost of prescribing other lipid-lowering therapies such as the PCSK9 inhibitors leads to suboptimal cholesterol management in ASCVD patients. Patients concerns about medication side effects and lack of understanding of their ASCVD risk are causes of poor adherence to their lipid-lowering therapy as are barriers at a system level.

Summary: To improve cholesterol management in ASCVD patients will require an integrated approach targeting the provider, the patient and the system. There is a need for further education of clinicians on the importance of intensive LDL-C lowering in ASCVD patients and greater use of nonstatin LDL-C-lowering therapies for those patients on a maximally tolerated statin who have not achieved their guideline-directed LDL-C goal. This will require shared decision-making with a focus on patient education and patient-clinician communication so that the clinician's goals and aims align with that of the patient.

Purpose of review: Several large studies have shown increased mortality due to all-causes and to atherosclerotic cardiovascular disease. In most clinical settings, plasma HDL-cholesterol is determined as a sum of free cholesterol and cholesteryl ester, two molecules with vastly different metabolic itineraries. We examine the evidence supporting the concept that the pathological effects of elevations of plasma HDL-cholesterol are due to high levels of the free cholesterol component of HDL-C.

Recent findings: In a small population of humans, a high plasma HDL-cholesterol is associated with increased mortality. Similar observations in the HDL-receptor deficient mouse (Scarb1 -/- ), a preclinical model of elevated HDL-C, suggests that the pathological component of HDL in these patients is an elevated plasma HDL-FC.

Summary: Collective consideration of the human and mouse data suggests that clinical trials, especially in the setting of high plasma HDL, should measure free cholesterol and cholesteryl esters and not just total cholesterol.

Background: Familial hypercholesterolemia (FH) is a genetic disorder characterized by elevated low-density lipoprotein cholesterol (LDL-C) levels and premature cardiovascular disease (CVD). Both the heterozygous form and the very severe homozygous form can be diagnosed by genetic testing and by clinical criteria. Genetic testing can discern FH in a form caused by complete absence of the LDL-receptors, the negative variant and a form leading to reduced activity of the LDL receptors, the defective variant. The aim of this study is to provide more insight in the genotype-phenotype correlation in children and adolescents diagnosed with heterozygous FH (HeFH) and with homozygous FH (HoFH), specifically in relation to the clinical and therapeutic consequences of the negative and defective variant of FH.

Methods and results: Data of 5904 children with a tentative diagnosis of FH referred to our center for genetic testing were collected. A lipid-profile was present in 3494 children, who became the study cohort. In this large cohort of children, which includes 2714 HeFH and 41 HoFH patients, it is shown that receptor negative variants are associated with significant higher LDL-C levels in HeFH patients than receptor defective variants (6.0 versus 4.9 mmol/L; p  < 0.001). A negative/negative variant is associated with a significant higher LDL-C level jn HoFH patients than a negative/defective variant, which in itself has a higher LDL-C level than a defective/defective variant. Significantly more premature CVD is present in close relatives of children with HeFH with negative variants compared to close relatives of HeFH children with defective variants (75% vs 59%; p  < 0.001).

Conclusions: Performing genetic testing and identifying the type of underlying genetic variant is of added value in order to distinguish between pediatric patients with higher risks of premature CVD and to identify those that will benefit most from new types of lipid-lowering therapies. Since in children the phenotype of FH is less affected by environmental factors, the study substantiates the genotype-phenotype correlation in this large pediatric population.

Purpose of review: The triglyceride-rich apoB lipoprotein particles make up a minority of the apoB particles in plasma. They vary in size, in lipid, and in protein content. Most are small enough to enter the arterial wall and therefore most are atherogenic. But how important a contribution TRL particles make to the total risk created by the apoB lipoproteins remains controversial. A recent Mendelian randomization analysis determined that the cardiovascular risk related to the cholesterol within these apoB particles--the TRL cholesterol--was greater than--and independent of--the risk related to apoB. If correct, these observations have major clinical significance.

Recent findings: Accordingly, we have analyzed these results in detail. In our view, the independent strength of the association between TRL cholesterol and apoB with cardiovascular risk seems inconsistent with the biological connections between apoB and cholesterol as integral and highly correlated constituents of apoB particles. These results are also inconsistent with other lines of evidence such as the results of the fibrate randomized clinical trials. Moreover, we are also concerned with other aspects of the analysis.

Summary: We do not regard the issue as settled. However, this enquiry has led us to a fuller understanding of the determinants of the cholesterol content of the TRL apoB particles and the complex processing of cholesterol amongst the plasma lipoproteins.

Purpose of review: This article reviews PCSK9 inhibitors (PCSK9i) with a focus on clinically relevant studies published in the last 18 months.

Recent findings: Prespecified subgroup evaluations, secondary analyses, and open-label extension studies from the two landmark trials, FOURIER and ODYSSEY Outcomes, have provided new data on the safety and efficacy of the monoclonal PCSK9 antibodies evolocumab and alirocumab. Recent studies of PCSK9i early in ACS and post percutaneous coronary intervention have explored early effects on biomarkers and plaque morphology with various imaging modalities. Two large outcome trials with PCSK9i in lower risk patients without prior myocardial infarction or stroke are ongoing and could expand the eligible population for these potent therapies. Additionally, novel methods to inhibit PCSK9 using oral administration, vaccination, and gene therapy are in various stages of clinical development.

Summary: PCSK9i represent a potent class of lipid-lowering therapies that are well tolerated and effective in a wide group of patients with high-risk atherosclerotic cardiovascular disease. Ongoing studies of PCSK9i in patients at lower risk and with acute myocardial infarction have the potential to broaden their indication. Alternative methods of PCSK9i are being evaluated and could provide easier and less expensive options for this important class of medication.