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Purpose of Review: To better define the metabolism of sphingosine-1-phosphate (S1P), its transport in plasma and its interactions with S1P receptors on vascular cells, and to evaluate the effect of statin treatment on the subnormal plasma levels of high-density lipoprotein (HDL)-bound S1P characteristic of the atherogenic dyslipidemia of metabolic syndrome (MetS)., Recent Findings: Neither clinical intervention trials targeted to raising high-density lipoprotein-cholesterol (HDL-C) levels nor human genome-wide association studies (GWAS) studies have provided evidence to support an atheroprotective role of HDL. Recently however a large monogenic univariable Mendelian randomization on the N396S mutation in the gene encoding endothelial lipase revealed a causal protective effect of elevated HDL-C on coronary artery disease conferred by reduced enzyme activity. Given the complexity of the HDL lipidome and proteome, components of HDL other than cholesterol may in all likelihood contribute to such a protective effect. Among HDL lipids, S1P is a bioactive sphingolipid present in a small proportion of HDL particles (about 5%); indeed, S1P is preferentially enriched in small dense HDL3. As S1P is bound to apolipoprotein (apo) M in HDL, such enrichment is consistent with the elevated apoM concentration in HDL3. When HDL/apoM-bound S1P acts on S1P1 or S1P3 receptors in endothelial cells, potent antiatherogenic and vasculoprotective effects are exerted; those exerted by albumin-bound S1P at these receptors are typically weaker. When HDL/apoM-bound S1P binds to S1P2 receptors, proatherogenic effects may potentially be induced. Subnormal plasma levels of HDL-associated S1P are typical of dyslipidemic individuals at high cardiovascular risk and in patients with coronary heart disease. International Guidelines recommend statin treatment as first-line lipid lowering therapy in these groups. The cardiovascular benefits of statin therapy are derived primarily from reduction in low-density lipoprotein (LDL)-cholesterol, although minor contributions from pleiotropic actions cannot be excluded. Might statin treatment therefore normalize, directly or indirectly, the subnormal levels of S1P in dyslipidemic subjects at high cardiovascular risk? Our unpublished findings in the CAPITAIN study (ClinicalTrials.gov: NCT01595828), involving a cohort of obese, hypertriglyceridemic subjects (n = 12) exhibiting the MetS, showed that pitavastatin calcium (4 mg/day) treatment for 180days was without effect on either total plasma or HDL-associated S1P levels, suggesting that statin-mediated improvement of endothelial function is not due to normalization of HDL-bound S1P. Statins may however induce the expression of S1P1 receptors in endothelial cells, thereby potentiating increase in endothelial nitric oxide synthase response to HDL-bound S1P, with beneficial downstream vasculoprotective effects., Summary: Current evidence indicates that S1P in small dense HDL3 containing apoM exerts antiatherogenic effects and that statins exert vasculoprotective effects through activation of endothelial cell S1P1 receptors in response to HDL/apoM-bound S1P., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Elevated levels of low-density lipoprotein cholesterol (LDL-C) are associated with increased risk of coronary heart disease and stroke. Guidelines for the management of dyslipidaemia from the European Society of Cardiology (ESC) and the European Atherosclerosis Society (EAS) were updated in late 2019 in light of recent intervention trials involving the use of innovative lipid-lowering agents in combination with statins. The new guidelines advocate achieving very low LDL-C levels in individuals at highest risk, within the paradigm of 'lower is better'. With the advent of combination therapy using ezetimibe and/or proprotein convertase subtilisin/kexin type 9 inhibitors in addition to statins, the routine attainment of extremely low LDL-C levels in the clinic has become a reality. Moreover, clinical trials in this setting have shown that, over the 5-7 years of treatment experience to date, profound LDL-C lowering leads to further reduction in cardiovascular events compared with more moderate lipid lowering, with no associated safety concerns. These reassuring findings are bolstered by genetic studies showing lifelong very low LDL-C levels (<1.4 mmol/L; <55 mg/dL) are associated with lower cardiovascular risk than in the general population, with no known detrimental health effects. Nevertheless, long-term safety studies are required to consolidate the present evidence base. This review summarises key data supporting the ESC/EAS recommendation to reduce markedly LDL-C levels, with aggressive goals for LDL-C in patients at highest risk, and provides expert opinion on its significance for clinical practice., Competing Interests: Competing interests: CP has received honoraria from Amgen, Daiichi Sankyo and Dalcor. JC has received research funding from Amgen, Kowa and Pfizer; and honoraria for speakers’ bureau activities and consultancy from Amarin, Amgen, AstraZeneca, Daiichi Sankyo, Merck Sharp & Dohme, Pfizer, Regeneron and Sanofi. UL has received honoraria for lectures from Amgen, Daiichi Sankyo, Novartis and Sanofi. LM has received honoraria for lectures and advisory work from Amarin, Amgen, Amryn, Mylan, Regeneron, Sanofi and Servier. MS is an employee of Amgen., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

There is an unmet clinical need to reduce residual cardiovascular risk attributable to apolipoprotein B-containing lipoproteins, particularly low-density lipoprotein and remnant particles. Pharmacological targeting of messenger RNA represents an emerging, innovative approach. Two major classes of agents have been developed-antisense oligonucleotides and small interfering RNA. Early problems with their use have been overcome by conjugation with N-acetylgalactosamine, an adduct that targets their delivery to the primary site of action in the liver. Using these agents to inhibit the translation of key regulatory proteins such as PCSK9, apolipoprotein CIII, apolipoprotein(a), and angiopoietin-like 3 has been shown to be effective in attenuating dyslipidemic states. Cardiovascular outcome trials with N-acetylgalactosamine-conjugated RNA-targeting drugs are ongoing. The advantages of these agents include long dosing intervals of up to 6 months and the potential to regulate the abundance of any disease-related protein. Long-term safety has yet to be demonstrated in large-scale clinical trials., (Copyright © 2020 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Atherogenic LDL particles are physicochemically and metabolically heterogeneous. Can bioactive lipid cargo differentiate LDL subclasses, and thus potential atherogenicity? What is the effect of statin treatment? Obese hypertriglyceridemic hypercholesterolemic males [n = 12; lipoprotein (a) <10 mg/dl] received pitavastatin calcium (4 mg/day) for 180 days in a single-phase unblinded study. The lipidomic profiles (23 lipid classes) of five LDL subclasses fractionated from baseline and post-statin plasmas were determined by LC-MS. At baseline and on statin treatment, very small dense LDL (LDL5) was preferentially enriched (up to 3-fold) in specific lysophospholipids {LPC, lysophosphatidylinositol (LPI), lysoalkylphosphatidylcholine [LPC(O)]; 9, 0.2, and 0.14 mol per mole of apoB, respectively; all P < 0.001 vs. LDL1-4}, suggesting elevated inflammatory potential per particle. In contrast, lysophosphatidylethanolamine was uniformly distributed among LDL subclasses. Statin treatment markedly reduced absolute plasma concentrations of all LDL subclasses (up to 33.5%), including LPC, LPI, and LPC(O) contents (up to -52%), consistent with reduction in cardiovascular risk. Despite such reductions, lipotoxic ceramide load per particle in LDL1-5 (1.5-3 mol per mole of apoB; 3-7 mmol per mole of PC) was either conserved or elevated. Bioactive lipids may constitute biomarkers for the cardiometabolic risk associated with specific LDL subclasses in atherogenic dyslipidemia at baseline, and with residual risk on statin therapy., (Copyright © 2020 Chapman et al.)

Genome sequencing and gene-based therapies appear poised to advance the management of rare lipoprotein disorders and associated dyslipidaemias. However, in practice, underdiagnosis and undertreatment of these disorders are common, in large part due to interindividual variability in the genetic causes and phenotypic presentation of these conditions. To address these challenges, the European Atherosclerosis Society formed a task force to provide practical clinical guidance focusing on patients with extreme concentrations (either low or high) of plasma low-density lipoprotein cholesterol, triglycerides, or high-density lipoprotein cholesterol. The task force also recognises the scarcity of quality information regarding the prevalence and outcomes of these conditions. Collaborative registries are needed to improve health policy for the care of patients with rare dyslipidaemias., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background and Aims: Research on the biologic activities of HDL, such as cholesterol efflux capacity and HDL composition, has allowed the understanding of the effect of interventions directed to improve cardiovascular risk. Previously, statin therapy has shown conflicting results about its effects on cholesterol efflux capacity of HDL; the underlying mechanisms are unclear but studies with positive effects are associated with an increase of HDL-cholesterol levels. We investigated if 10 weeks of atorvastatin therapy changes HDL efflux capacity and the chemical composition of its subpopulations., Methods: In a before-after design basis, HDL-cholesterol levels, chemical composition and cholesterol efflux capacity from HDL subpopulations isolated by isophynic ultracentrifugation were assessed in plasma samples from 60 patients with type 2 diabetes mellito (T2DM) at baseline and after 10 weeks of treatment with 20 mg atorvastatin. Cholesterol efflux was measured from human THP-1 cells using large, light HDL2b and small, dense 3c subpopulations as well as total HDL as acceptors. Changes of cholesterol efflux and chemical composition of HDL after treatment were analyzed. Correlations among variables potentially involved in cholesterol efflux were evaluated., Results: A significant decrease of 4% in HDL-cholesterol levels was observed from 47 (42-54) to 45 (39-56) mg/dL, p = 0.02. Cholesterol efflux from total-HDL and HDL2b and 3c subfractions was maintained unchanged after treatment. The total mass of HDL remained unaffected, except for the HDL3a subpopulation accounted for by a significant increase in total protein content. No significant correlations for variables previously known to be associated with cholesterol efflux were found in our study., Conclusions: Short therapy of 10 weeks with 20 mg of atorvastatin does not modify the cholesterol efflux capacity neither the total mass of HDL2b, HDL3c and total HDL. The discrepancy with previous reports may be due to the selective effects among different classes of statins or differences in the approaches to measure cellular cholesterol efflux., (Copyright © 2018. Published by Elsevier B.V.)

Background: Niacin as an adjunct to statin treatment to reduce cardiovascular risk is questioned., Objective: To evaluate interrelationships between the effects of niacin on mixed dyslipidemia and a spectrum of metabolic and inflammatory biomarkers., Methods: Obese, nondiabetic, hypertriglyceridemic males (n = 19) with low high-density lipoprotein-cholesterol levels received extended-release nicotinic acid for 8 weeks. Multiple biomarkers were measured using enzyme-linked immunosorbent assay, enzymatic/absorptiometric, or multiplex biochip assays. Treatment effects were determined for each variable and a differential correlation network created on the basis of univariate correlations between baseline and response to niacin treatment for all pairs of variables., Results: Extended-release niacin treatment favoured normalization of plasma lipid and apolipoprotein profile. Plasma markers of inflammation, hepatic function, cellular adhesion and proliferation, and macrophage phenotype were attenuated; however, insulin resistance increased. Differential network analysis revealed that changes in triglycerides and high-density lipoprotein-cholesterol were closely linked; equally, niacin mediated reductions in total cholesterol, apolipoprotein B, low-density lipoprotein-cholesterol and lipoprotein(a) clustered together, as did homeostatic model assessment of insulin resistance, insulin, and interleukin-6 levels. Two clusters of inflammatory markers were identified, involving (1) intercellular adhesion molecule 1 and high-sensitive C-reactive protein and (2) soluble tumor necrosis factor receptors; and novel clusters involving matrix metallopeptidase 9 and apolipoprotein E, and adiponectin and cystatin C, respectively, were equally revealed. At lower stringency, lipid and insulin resistance clusters were linked; a C-reactive protein-centered cluster linked reduction in apolipoprotein CIII to intercellular adhesion molecule 1, gamma-glutamyltransferase, soluble tumor necrosis factor receptors, and E-selectin., Conclusion: A niacin-mediated trend to normalize atherogenic mixed dyslipidemia was intimately linked to attenuation of biomarkers of inflammation, cell adhesion, hepatic dysfunction and cell proliferation, but to enhanced insulin resistance and plasma homocysteine elevation., (Copyright © 2018 National Lipid Association. Published by Elsevier Inc. All rights reserved.)

Background: Statins impact the metabolism, concentrations, composition, and function of circulating lipoproteins., Objective: We evaluated time course relationships between statin-mediated reduction in atherogenic apolipoprotein B (ApoB)-containing particles and dynamic intravascular remodeling of ApoAI-containing lipoprotein subpopulations in the mixed dyslipidemia of metabolic syndrome., Methods: Insulin-resistant, hypertriglyceridemic, hypercholesterolemic, obese males (n = 12) were treated with pitavastatin (4 mg/d) and response evaluated at 6, 42, and 180 days., Results: Reduction in low-density lipoprotein (LDL) cholesterol, ApoB, and triglycerides (TGs) was essentially complete at 42 days (-38%, -32%, and -35%, respectively); rapid reduction equally occurred in remnant cholesterol, ApoCII, CIII, and E levels (day 6; -35%, -50%, -23%, and -26%, respectively). Small dense LDLs (LDL4 and LDL5 subpopulations) predominated at baseline and were markedly reduced on treatment (-29% vs total LDL mass). Cholesteryl ester (CE) transfer protein activity and mass decreased progressively (-18% and -16%, respectively); concomitantly, TG depletion (up to -49%) and CE enrichment occurred in all high-density lipoprotein (HDL) particle subpopulations with normalization of CE/TG mass ratio at 180 days. ApoAI was redistributed from LpAI to LpAI:AII particles in HDL2a and HDL3a subpopulations; ApoCIII was preferentially depleted from LpAI:AII-rich particles on treatment., Conclusion: Overall, statin action exhibits duality in mixed dyslipidemia, as CE transfer protein-mediated normalization of the HDL CE/TG core lags markedly behind subacute reduction in elevated levels of atherogenic ApoB-containing lipoproteins. Normalization of the HDL neutral lipid core is consistent with enhanced atheroprotective function. The HDL CE/TG ratio constitutes a metabolomic marker of perturbed HDL metabolism in insulin-resistant states, equally allowing monitoring of statin impact on HDL metabolism, structure, and function., (Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.)

Atherogenic mixed dyslipidemia associates with oxidative stress and defective HDL antioxidative function in metabolic syndrome (MetS). The impact of statin treatment on the capacity of HDL to inactivate LDL-derived, redox-active phospholipid hydroperoxides (PCOOHs) in MetS is indeterminate. Insulin-resistant, hypertriglyceridemic, hypertensive, obese males were treated with pitavastatin (4 mg/day) for 180 days, resulting in marked reduction in plasma TGs (-41%) and LDL-cholesterol (-38%), with minor effects on HDL-cholesterol and apoAI. Native plasma LDL (baseline vs. 180 days) was oxidized by aqueous free radicals under mild conditions in vitro either alone or in the presence of the corresponding pre- or poststatin HDL2 or HDL3 at authentic plasma mass ratios. Lipidomic analyses revealed that statin treatment i) reduced the content of oxidizable polyunsaturated phosphatidylcholine (PUPC) species containing DHA and linoleic acid in LDL; ii) preferentially increased the content of PUPC species containing arachidonic acid (AA) in small, dense HDL3; iii) induced significant elevation in the content of phosphatidylcholine and phosphatidylethanolamine (PE) plasmalogens containing AA and DHA in HDL3; and iv) induced formation of HDL3 particles with increased capacity to inactivate PCOOH with formation of redox-inactive phospholipid hydroxide. Statin action attenuated LDL oxidability Concomitantly, the capacity of HDL3 to inactivate redox-active PCOOH was enhanced relative to HDL2, consistent with preferential enrichment of PE plasmalogens and PUPC in HDL3., (Copyright © 2016 by the American Society for Biochemistry and Molecular Biology, Inc.)

The impact of statin treatment on the abnormal plasma lipidome of mixed dyslipidemic patients with metabolic syndrome (MetS), a group at increased risk of developing diabetes, was evaluated. Insulin-resistant hypertriglyceridemic hypertensive obese males (n = 12) displaying MetS were treated with pitavastatin (4 mg/day) for 180 days; healthy normolipidemic age-matched nonobese males (n = 12) acted as controls. Statin treatment substantially normalized triglyceride (-41%), remnant cholesterol (-55%), and LDL-cholesterol (-39%), with minor effect on HDL-cholesterol (+4%). Lipidomic analysis, normalized to nonHDL-cholesterol in order to probe statin-induced differences in molecular composition independently of reduction in plasma cholesterol, revealed increment in 132 of 138 lipid species that were subnormal at baseline and significantly shifted toward the control group on statin treatment. Increment in alkyl- and alkenylphospholipids (plasmalogens) was prominent, and consistent with significant statin-induced increase in plasma polyunsaturated fatty acid levels. Comparison of the statin-mediated lipidomic changes in MetS with the abnormal plasma lipidomic profile characteristic of prediabetes and T2D in the Australian Diabetes, Obesity, and Lifestyle Study and San Antonio Family Heart Study cohorts by hypergeometric analysis revealed a significant shift toward the lipid profile of controls, indicative of a marked trend toward a normolipidemic phenotype. Pitavastatin attenuated the abnormal plasma lipidome of MetS patients typical of prediabetes and T2D., (Copyright © 2015 by the American Society for Biochemistry and Molecular Biology, Inc.)

Objective: This EAS Consensus Panel critically appraised evidence relevant to the benefit to risk relationship of functional foods with added plant sterols and/or plant stanols, as components of a healthy lifestyle, to reduce plasma low-density lipoprotein-cholesterol (LDL-C) levels, and thereby lower cardiovascular risk., Methods and Results: Plant sterols/stanols (when taken at 2 g/day) cause significant inhibition of cholesterol absorption and lower LDL-C levels by between 8 and 10%. The relative proportions of cholesterol versus sterol/stanol levels are similar in both plasma and tissue, with levels of sterols/stanols being 500-/10,000-fold lower than those of cholesterol, suggesting they are handled similarly to cholesterol in most cells. Despite possible atherogenicity of marked elevations in circulating levels of plant sterols/stanols, protective effects have been observed in some animal models of atherosclerosis. Higher plasma levels of plant sterols/stanols associated with intakes of 2 g/day in man have not been linked to adverse effects on health in long-term human studies. Importantly, at this dose, plant sterol/stanol-mediated LDL-C lowering is additive to that of statins in dyslipidaemic subjects, equivalent to doubling the dose of statin. The reported 6-9% lowering of plasma triglyceride by 2 g/day in hypertriglyceridaemic patients warrants further evaluation., Conclusion: Based on LDL-C lowering and the absence of adverse signals, this EAS Consensus Panel concludes that functional foods with plant sterols/stanols may be considered 1) in individuals with high cholesterol levels at intermediate or low global cardiovascular risk who do not qualify for pharmacotherapy, 2) as an adjunct to pharmacologic therapy in high and very high risk patients who fail to achieve LDL-C targets on statins or are statin- intolerant, 3) and in adults and children (>6 years) with familial hypercholesterolaemia, in line with current guidance. However, it must be acknowledged that there are no randomised, controlled clinical trial data with hard end-points to establish clinical benefit from the use of plant sterols or plant stanols., (Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.)

Atherogenic dyslipidemia is characterised by high levels of triglycerides, low levels of high-density lipoprotein-cholesterol (HDL-C), and moderate to marked elevations in low-density lipoprotein-cholesterol (LDL-C) concentrations; such dyslipidemia is further characterised by high apolipoprotein B (apoB): apolipoprotein A1 (apoA1) ratios. Numerous clinical trials have demonstrated that statins are effective in lowering LDL-C and reducing cardiovascular (CV) risk in people with dyslipidemia. However, the most effective treatments should target all of the key atherogenic features, rather than LDL-C alone. Pitavastatin is a new member of the statin class whose distinct pharmacological features translate into a broad spectrum of action on both apoB-containing and apoA1-containing lipoprotein components of the atherogenic lipid profile. The efficacy and safety of this statin has been demonstrated by a large clinical development programme conducted both in Japanese and Caucasian populations. Phase III and IV studies in a wide range of patients with primary hypercholesterolemia or combined dyslipidemia showed that 12 weeks' treatment with pitavastatin l-4 mg was well tolerated, significantly improved lipid profiles (including LDL-C, TG, and HDL-C levels) and increased the EAS-/NCEP ATP Ill-recommended LDL-C target attainment rate to a similar or greater degree as comparable doses of atorvastatin, simvastatin, or pravastatin. Results were similar across all patient groups and were generally sustained after 52 weeks of treatment. However, whereas the effects of atorvastatin and simvastatin on HDL-C levels remained constant over the long term, pitavastatin-treated patients experienced progressive and maintained elevations in HDL-C, ultimately increasing by up to 14.3% vs. initial baseline. In this context, it is significant that the in vitro studies of Yamashita et al. [J Atheroscler Thromb 2010;17:436-51] have shown pitavastatin to be distinguished by its potent stimulation of apoA1 production in hepatocyte-like cells. These findings suggest that pitavastatin may be highly efficacious in raising levels of lipid-poor apoA1 particles, which are known to be highly active in ABCA1-mediated cellular cholesterol efflux, an observation which is pertinent to the excessive accumulation of cholesterol in macrophage foam cells of the atherosclerotic plaque. Indeed, the intravascular remodelling and maturation of lipid-poor apoA1 particles is known to drive flux of apoA1, cholesterol and phospholipid through the HDL pathway. It is equally relevant that pitavastatin therapy has been shown to be efficacious in markedly reducing coronary atheroma volume in acute coronary syndrome patients in the JAPAN-ACS trial, a therapeutic effect which may be linked to its impact on apoA1/HDL metabolism and function. Overall, Phase III and IV studies demonstrate that pitavastatin 1-4 mg is well tolerated, attenuates the atherogenic lipid profile and increases LDL-C target attainment rates with a similar or greater efficacy to comparable doses of atorvastatin, simvastatin and pravastatin. Furthermore, pitavastatin may be particularly beneficial in high-risk patients with elevated concentrations of TG-rich lipoproteins and low levels of HDL-C, and in whom the atheroprotective function of HDL particles is typically defective; significantly, such patients typically exhibit persistent, residual cardiometabolic risk even when LDL-C is at goal. In this context, it is relevant that such patient groups cover a wide spectrum of metabolic diseases, including metabolic syndrome, type 2 diabetes, coronary disease, familial and non-familial forms of hypercholesterolemia, auto-immune diseases such as rheumatoid arthritis and lupus, renal disease and some forms of hepatic insufficiency., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

High-density lipoprotein (HDL) mediated reverse cholesterol transport (RCT) is regarded to be crucial for prevention of foam cell formation and atherosclerosis. ABC-transporter A1 (ABCA1) and scavenger receptor BI (SR-BI) are involved in the biogenesis of HDL and the selective delivery of HDL cholesterol to the liver, respectively. In the present study, we phenotypically characterized mice lacking these two proteins essential for HDL metabolism. ABCA1×SR-BI double knockout (dKO) mice showed severe hypocholesterolemia mainly due to HDL loss, despite a 90% reduction of HDL cholesterol uptake by liver. VLDL production was increased in dKO mice. However, non-HDL cholesterol levels were reduced, probably due to enhanced clearance via LRP1. Hepatobiliary cholesterol transport and fecal sterol excretion were not impaired in dKO mice. In contrast, the macrophage RCT in dKO mice was markedly impaired as compared to WT mice, associated with the accumulation of macrophage foam cells in the lung and Peyer's patches. Strikingly, no atherosclerotic lesion formation was observed in dKO mice. In conclusion, both ABCA1 and SR-BI are essential for maintaining a properly functioning HDL-mediated macrophage RCT, while the potential anti-atherosclerotic functions of ABCA1 and SR-BI are not evident in dKO mice due to the absence of pro-atherogenic lipoproteins., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Purpose of Review: A lipid triad involving an atherogenic dyslipidemia characterized by moderate/high LDL-C, low HDL-C, and elevated triglyceride (TG) occurs in numerous clinical settings associated with high cardiovascular risk. This article focuses on optimizing treatment of atherogenic dyslipidemias involving this lipid triad, emphasizing niacin-based or fibrate-based therapies., Recent Findings: Niacin-based therapies comprehensively improve the atherogenic lipid profile, lead to atherosclerosis regression, and exert benefits across a spectrum of cardiovascular endpoints in studies based on limited patient numbers. Fibrates impact TG, HDL-C, and LDL-C according to lipid phenotype and underlying metabolic abnormality. In a recent meta-analysis, fibrates significantly reduced major cardiovascular events (-10%) and coronary events (-13%) across a wide range of lipid phenotypes, but had no impact on stroke, sudden death, or mortality. The Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial in type 2 diabetic patients similarly showed no significant effect of fenofibrate + simvastatin (vs. simvastatin) on nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death; a subgroup (17%) with marked atherogenic dyslipidemia trended toward benefit. Both niacin and fibrates attenuate vascular inflammation but the potential clinical relevance is indeterminate., Summary: Optimal cardiovascular risk reduction in patients exhibiting the lipid triad requires integrated pharmacotherapy to normalize LDL-C, HDL-C, TGs, and potentially lipoprotein(a). Ongoing studies may provide definitive evidence of the impact of niacin plus statins on cardiovascular outcomes.

Cardiovascular disease (CVD) due to atherosclerosis of the arterial vessel wall and to thrombosis is the foremost cause of premature mortality and of disability-adjusted life years (DALYs) in Europe, and is also increasingly common in developing countries.1 In the European Union, the economic cost of CVD represents annually E192 billion1 in direct and indirect healthcare costs. The main clinical entities are coronary artery disease (CAD), ischaemic stroke, and peripheral arterial disease (PAD). The causes of these CVDs are multifactorial. Some of these factors relate to lifestyles, such as tobacco smoking, lack of physical activity, and dietary habits, and are thus modifiable. Other risk factors are also modifiable, such as elevated blood pressure, type 2 diabetes, and dyslipidaemias, or non-modifiable, such as age and male gender. These guidelines deal with the management of dyslipidaemias as an essential and integral part of CVD prevention. Prevention and treatment of dyslipidaemias should always be considered within the broader framework of CVD prevention, which is addressed in guidelines of the Joint European Societies’ Task forces on CVD prevention in clinical practice.2 – 5 The latest version of these guidelines was published in 20075; an update will become available in 2012. These Joint ESC/European Atherosclerosis Society (EAS) guidelines on the management of dyslipidaemias are complementary to the guidelines on CVD prevention in clinical practice and address not only physicians [e.g. general practitioners (GPs) and cardiologists] interested in CVD prevention, but also specialists from lipid clinics or metabolic units who are dealing with dyslipidaemias that are more difficult to classify and treat.

Even at low-density lipoprotein cholesterol (LDL-C) goal, patients with cardiometabolic abnormalities remain at high risk of cardiovascular events. This paper aims (i) to critically appraise evidence for elevated levels of triglyceride-rich lipoproteins (TRLs) and low levels of high-density lipoprotein cholesterol (HDL-C) as cardiovascular risk factors, and (ii) to advise on therapeutic strategies for management. Current evidence supports a causal association between elevated TRL and their remnants, low HDL-C, and cardiovascular risk. This interpretation is based on mechanistic and genetic studies for TRL and remnants, together with the epidemiological data suggestive of the association for circulating triglycerides and cardiovascular disease. For HDL, epidemiological, mechanistic, and clinical intervention data are consistent with the view that low HDL-C contributes to elevated cardiovascular risk; genetic evidence is unclear however, potentially reflecting the complexity of HDL metabolism. The Panel believes that therapeutic targeting of elevated triglycerides (≥ 1.7 mmol/L or 150 mg/dL), a marker of TRL and their remnants, and/or low HDL-C (<1.0 mmol/L or 40 mg/dL) may provide further benefit. The first step should be lifestyle interventions together with consideration of compliance with pharmacotherapy and secondary causes of dyslipidaemia. If inadequately corrected, adding niacin or a fibrate, or intensifying LDL-C lowering therapy may be considered. Treatment decisions regarding statin combination therapy should take into account relevant safety concerns, i.e. the risk of elevation of blood glucose, uric acid or liver enzymes with niacin, and myopathy, increased serum creatinine and cholelithiasis with fibrates. These recommendations will facilitate reduction in the substantial cardiovascular risk that persists in patients with cardiometabolic abnormalities at LDL-C goal.

Cardiovascular diseases (CVDs) account for ∼30% of mortality, worldwide. Of the nine common risk factors for CVDs, the multinational INTERHEART study showed that dyslipidaemia, defined as an elevated apolipoprotein (apo) B:apoA1 ratio, is one of the most significant. The effective management of dyslipidaemia is therefore essential for the reduction of CV risk. It is well established that lowering low-density lipoprotein-cholesterol (LDL-C) levels using statins significantly reduces the level of CV risk in people with dyslipidaemia. A meta-analysis of 14 clinical trials, for example, demonstrated that each mmol/L reduction in LDL-C was associated with a 12% reduction in all-cause mortality, a 19% reduction in coronary mortality, and a 21% reduction in the total risk of major vascular events. Based on the results from this and similar studies, international treatment guidelines recommend lowering LDL-C to <2.0-2.6 mmol/L (<77-100 mg/dL) in patients with established CVDs and to <1.8-2.0 mmol/L (<70-77 mg/dL), where possible. Among the seven commonly used statins, pitavastatin is frequently used in Japan, South Korea, Thailand and China; it has recently been licensed for use in the USA and is now in the final stages of national approval within Europe. The following reviews discuss the safety and efficacy of pitavastatin for the treatment of dyslipidaemia relative to atorvastatin, simvastatin, and pravastatin, and examine its additional benefits beyond LDL-C reduction and its potential role in clinical practice., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Background: Subnormal levels of plasma bilirubin levels are associated with premature coronary artery disease and cardiovascular morbidity. Plasma gamma-glutamyltransferase (GGT) activity is linked to bilirubin level in hepatic disease and elevated GGT is equally associated with hepatic steatosis, a frequent feature of metabolic syndrome (MS). In order to assess the potential relationship between GGT activity and bilirubin levels in subjects exhibiting features of the metabolic syndrome, we determined circulating bilirubin levels and GGT activity in a cohort of dyslipidemic patients., Methods and Results: This cross-sectional study involved patients (n=1433) displaying atherogenic dyslipidemia in primary prevention referred to our Prevention Center. Among these patients, 25% presented with MS as defined by recent NCEP ATP III criteria. Circulating levels of transaminases, as well as GGT activity, were elevated in MS patients; by contrast, bilirubin concentrations were significantly lower in such patients as compared to those lacking this syndrome (p<10-4 for all comparisons). Comparisons of patient groups on the basis of the number of MS criteria which were concomitantly present revealed a progressive decrease in mean bilirubin levels; this reduction paralleled a progressive increase in mean GGT activity as a function of the number of MS components in the overall population (p value for trend<10-4)., Conclusion: Elevation in systemic GGT activity, which is characterized by extended generation of ROS, together with potentially deficient bilirubin-mediated antioxidative capacity of plasma, may therefore constitute key components of the systemic oxidative stress typical of metabolic syndrome., (Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.)

Although statin therapy represents a cornerstone of cardiovascular disease (CVD) prevention, a major residual CVD risk (60-70% of total relative risk) remains, attributable to both modifiable and non-modifiable risk factors. Among the former, low levels of HDL-C together with elevated triglyceride (TG)-rich lipoproteins and their remnants represent major therapeutic targets. The current pandemic of obesity, metabolic syndrome, and type 2 diabetes is intimately associated with an atherogenic dyslipidemic phenotype featuring low HDL-C combined with elevated TG-rich lipoproteins and small dense LDL. In this context, there is renewed interest in pharmacotherapeutic strategies involving niacin and fibrates in monotherapy and in association with statins. This comprehensive, critical review of available data in dyslipidemic subjects indicates that niacin is more efficacious in raising HDL-C than fibrates, whereas niacin and fibrates reduce TG-rich lipoproteins and LDL comparably. Niacin is distinguished by its unique capacity to effectively lower Lp(a) levels. Several studies have demonstrated anti-atherosclerotic action for both niacin and fibrates. In contrast with statin therapy, the clinical benefit of fibrates appears limited to reduction of nonfatal myocardial infarction, whereas niacin (frequently associated with statins and/or other agents) exerts benefit across a wider range of cardiovascular endpoints in studies involving limited patient numbers. Clearly the future treatment of atherogenic dyslipidemias involving the lipid triad, as exemplified by the occurrence of the mixed dyslipidemic phenotype in metabolic syndrome, type 2 diabetes, renal, and auto-immune diseases, requires integrated pharmacotherapy targeted not only to proatherogenic particles, notably VLDL, IDL, LDL, and Lp(a), but also to atheroprotective HDL., (Copyright 2010 Elsevier Inc. All rights reserved.)

Although technologies for lipidomic and proteomic investigations have developed very recently, lipidomic and proteomic studies of plasma lipoproteins have already provided several impressive examples of detailed characterization of distinct metabolic pathways potentially involved in lipoprotein metabolism in both health and disease states (obesity, insulin resistance, fatty liver disease) as well as under lifestyle and dietary modification (fish consumption, carbohydrates, probiotics) and lipid-modifying treatments (statins, low-density lipoprotein apheresis). Available lipidomic methodologies have facilitated detailed characterization of lipid classes and molecular species present in plasma as well as in lipoprotein fractions. Together with emerging proteomic techniques, lipidomics of plasma lipoproteins will soon provide molecular details of lipoprotein composition, which will ultimately be translated into integrated knowledge of the structure, metabolism, and function of lipoproteins in health and disease.

Despite achieving targets for low-density lipoprotein (LDL) cholesterol, blood pressure, and glycemia in accordance with current standards of care, patients with dyslipidemia remain at high residual risk of vascular events. Atherogenic dyslipidemia, characterized by elevated triglycerides and low levels of high-density lipoprotein (HDL) cholesterol, often with elevated apolipoprotein B and non-HDL cholesterol, is common in patients with established cardiovascular disease (CVD), type 2 diabetes mellitus, or metabolic syndrome and contributes to both macrovascular and microvascular residual risk. However, atherogenic dyslipidemia is largely underdiagnosed and undertreated in clinical practice. The Residual Risk Reduction Initiative (R3i) was established to address this highly relevant clinical issue. The aims of this position paper are (1) to highlight evidence that atherogenic dyslipidemia is associated with residual macrovascular and microvascular risk in patients at high risk for CVD, despite current standards of care for dyslipidemia and diabetes; and (2) to recommend therapeutic intervention for reducing this residual vascular risk supported by evidence and expert consensus. Lifestyle modification with nutrition and exercise is an important, effective, and underutilized first step in reducing residual vascular risk. Therapeutic intervention aimed at achievement of all lipid targets is also often required. Combination lipid-modifying therapy, with the addition of niacin, a fibrate, or omega-3 fatty acids to statin therapy, increases the probability of achieving all lipid goals. Outcomes studies are in progress to evaluate whether these combination treatment strategies translate to a clinical benefit greater than that achieved with statins alone. The R3i highlights the need to address with lifestyle and/or pharmacotherapy the high level of residual risk of CVD events and microvascular complications among patients with dyslipidemia receiving therapy for high levels of LDL cholesterol and for diabetes in accordance with current standards of care.

Despite current standards of care aimed at achieving targets for low-density lipoprotein (LDL) cholesterol, blood pressure and glycaemia, dyslipidaemic patients remain at high residual risk of vascular events. Atherogenic dyslipidaemia, specifically elevated triglycerides and low levels of high-density lipoprotein (HDL) cholesterol, often with elevated apolipoprotein B and non-HDL cholesterol, is common in patients with established cardiovascular disease, type 2 diabetes, obesity or metabolic syndrome and is associated with macrovascular and microvascular residual risk. The Residual Risk Reduction Initiative (R3I) was established to address this important issue. This position paper aims to highlight evidence that atherogenic dyslipidaemia contributes to residual macrovascular risk and microvascular complications despite current standards of care for dyslipidaemia and diabetes, and to recommend therapeutic intervention for reducing this, supported by evidence and expert consensus. Lifestyle modification is an important first step. Additionally, pharmacotherapy is often required. Adding niacin, a fibrate or omega-3 fatty acids to statin therapy improves achievement of all lipid risk factors. Outcomes studies are evaluating whether these strategies translate to greater clinical benefit than statin therapy alone. In conclusion, the R3I highlights the need to address with lifestyle and/or pharmacotherapy the high level of residual vascular risk among dyslipidaemic patients who are treated in accordance with current standards of care.

Subnormal levels of HDL cholesterol constitute a major cardiovascular risk factor. Inhibitors of cholesteryl ester transfer protein (CETP) are presently the most potent HDL-raising agents. Torcetrapib was the first CETP inhibitor to enter a large-scale, prospective, placebo-controlled interventional trial, which was prematurely terminated in December 2006 because of excess cardiovascular and noncardiovascular mortality in the active treatment group. Therapy with torcetrapib was associated with considerable increases in aldosterone level and blood pressure and changes in serum electrolytes indicative of mineralocorticoid excess. These findings indicate that torcetrapib has off-target toxic effects unrelated to HDL raising that involve the activation of mineralocorticoid receptors by aldosterone and result in the induction of hypertension. In contrast with torcetrapib, other CETP inhibitors such as JTT-705 and MK-825 do not increase blood pressure in humans, an observation which discounts a class effect. The available data do not, however, exclude potential adverse effects of CETP inhibition such as the generation of HDL particles that have deficient biological activities and a deleterious impact on reverse cholesterol transport and steroid metabolism. Normalization of both defective HDL function and diminished HDL levels should, therefore, be the focus of pharmacological HDL raising in future studies.

Hypertension, a prevalent risk factor for cardiovascular disease, frequently occurs in conjunction with metabolic disturbances and in particular with dyslipidaemia; such comorbidity presents in more than one-third of hypertensive patients. Moreover, hypertension and dyslipidaemia often manifest concomitantly in the clinical context of obesity and insulin resistance. In this setting, distinct metabolic anomalies may account for the development of both conditions, and may equally act to exacerbate their effects on vascular dysfunction. Significantly, hypertension and dyslipidaemia are linked mechanistically and may act in synergy at the arterial wall to enhance atherosclerosis. In this review, we identify potential mechanisms underlying the pathophysiological interaction between hypertension and dyslipidaemia at the cellular and molecular levels, and which may underlie elevated cardiovascular risk in obesity and insulin resistance. Finally, the clinical evidence supporting the beneficial effects of an integrated pharmacotherapeutic strategy to the reduction of cardiovascular risk in patients with insulin resistance, type 2 diabetes and the metabolic syndrome is critically discussed.

Background: Prospective cohort studies have revealed that plasma gamma-glutamyltransferase (GGT) activity exhibits a positive association with coronary artery disease. GGT which is equally elevated in metabolic syndrome (MS), is the major regulator of circulating concentrations of thiol compounds derived from glutathione (GSH) cleavage, ie, cysteine and cysteinyl glycine. We compared the circulating thiol profile in a cohort of patients displaying atherogenic dyslipidemia with and without MS., Methods and Results: This cross-sectional study involved 1131 dyslipidemic patients in primary prevention of whom 26% presented with MS. GGT activity and plasma cysteinyl-glycine and cysteine concentrations were higher in MS patients; by contrast, levels of GSH were significantly lower (P<10 to 4 for all comparisons versus patients without MS). We compared patient groups on the basis of the number of MS criteria which were concomitantly present. A progressive decrease in glutathione levels in contrast to a progressive increase in both cysteinyl-glycine and cysteine levels, and GGT activity, was observed as a function of the number of MS components in the overall population (P for trend <10(-6))., Conclusions: Dyslipidemic patients exhibiting MS are characterized by elevated GGT activity which is associated with perturbed metabolism of thiol compounds.

The concept that macrophages can become foam cells as a result of a disturbed balance between the uptake of cholesterol from lipoproteins and cholesterol efflux is generally accepted. ABCA1 and ABCG1 are two cholesterol transporters that may act sequentially to remove cellular cholesterol, but currently their combined role in vivo is unknown. We report here that targeted disruption of both ABCA1 and ABCG1 in mice, despite severe plasma hypocholesterolemia, leads to massive lipid accumulation and foam cell formation of tissue macrophages. A complete ablation of cellular cholesterol efflux in vitro is observed, whereas in vivo macrophage-specific reverse cholesterol transport to the feces is markedly decreased. Despite the massive foam cell formation of tissue macrophages, no lipid accumulation was observed in the vascular wall, even in mice of 1 year old, indicating that the double knockout mice, possibly because of their hypocholesterolemia, lack the trigger to attract macrophages to the vessel wall. In conclusion, even under hypocholesterolemic conditions macrophages can be converted into foam cells, and ABCA1 and ABCG1 play an essential role in the prevention of foam cell formation.

The metabolic syndrome and type 2 diabetes are insulin-resistant states which are commonly associated with an atherogenic dyslipidaemia involving mild to moderately elevated triglycerides, a preponderance of small, dense low-density lipoprotein (LDL) particles and low levels of high-density lipoprotein cholesterol (HDL-C). In addition, there is a spectrum of qualitative changes in the lipoprotein profile, particularly in the functional capacity of HDL to facilitate cellular cholesterol efflux and to protect LDL against oxidative modification. Together, these quantitative and qualitative anomalies promote elevated oxidative stress, endothelial dysfunction and inflammation, which drive the development of premature atherosclerotic cardiovascular disease. Moreover, recent evidence indicates that this dyslipidaemic profile may play a critical role in the development and progression of diabetic microvascular disease. An integrated therapeutic approach to correct both the quantitative and qualitative changes characteristic of diabetic dyslipidaemia clearly constitutes a priority for reduction of both macrovascular and microvascular risk.

High-density lipoproteins (HDL) possess key atheroprotective biological properties, including cellular cholesterol efflux capacity, and anti-oxidative and anti-inflammatory activities. Plasma HDL particles are highly heterogeneous in physicochemical properties, metabolism, and biological activity. Within the circulating HDL particle population, small, dense HDL particles display elevated cellular cholesterol efflux capacity, afford potent protection of atherogenic low-density lipoprotein against oxidative stress and attenuate inflammation. The antiatherogenic properties of HDL can, however be compromised in metabolic diseases associated with accelerated atherosclerosis. Indeed, metabolic syndrome and type 2 diabetes are characterized not only by elevated cardiovascular risk and by low HDL-cholesterol (HDL-C) levels but also by defective HDL function. Functional HDL deficiency is intimately associated with alterations in intravascular HDL metabolism and structure. Indeed, formation of HDL particles with attenuated antiatherogenic activity is mechanistically related to core lipid enrichment in triglycerides and cholesteryl ester depletion, altered apolipoprotein A-I (apoA-I) conformation, replacement of apoA-I by serum amyloid A, and covalent modification of HDL protein components by oxidation and glycation. Deficient HDL function and subnormal HDL-C levels may act synergistically to accelerate atherosclerosis in metabolic disease. Therapeutic normalization of attenuated antiatherogenic HDL function in terms of both particle number and quality of HDL particles is the target of innovative pharmacological approaches to HDL raising, including inhibition of cholesteryl ester transfer protein, enhanced lipidation of apoA-I with nicotinic acid and infusion of reconstituted HDL or apoA-I mimetics. A preferential increase in circulating concentrations of HDL particles possessing normalized antiatherogenic activity is therefore a promising therapeutic strategy for the treatment of common metabolic diseases featuring dyslipidemia, inflammation, and premature atherosclerosis.

Our understanding of the relationship between the atheroprotective activities of HDL and heterogeneity of HDL particles has advanced greatly. HDL particles are highly heterogeneous in structure, intravascular metabolism and antiatherogenic activity. In this review, we discuss new findings on the antiatherogenic properties of HDL particles. Small, dense HDL possesses potent antioxidative activity but this is compromised under conditions of atherogenic dyslipidemia. HDL functional deficiency frequently coincides with reductions in HDL-cholesterol concentration and alterations in HDL metabolism and structure. Formation of small, dense HDL particles with attenuated antiatherogenic activity can be mechanistically related to HDL enrichment in triglycerides and in serum amyloid A, depletion of cholesteryl esters, covalent modification of HDL apolipoproteins and attenuated antiatherogenic function of apolipoprotein AI. Low circulating levels of HDL cholesterol might, therefore, be associated with the defective functionality of small HDL particles of abnormal structure and composition. In common metabolic diseases, such as type 2 diabetes and metabolic syndrome, deficiency of HDL particle number and function favor accelerated atherosclerosis. Therapeutic normalization of the quantity, quality and biological activities of HDL particles thus represents a novel approach to attenuating atherosclerosis in dyslipidemic individuals with metabolic disease. Cholesteryl ester transfer protein inhibitors, nicotinic acid, reconstituted HDL and other HDL-raising agents are being investigated. Induction of selective increase in the circulating concentrations of small, dense HDL3 particles with increased antiatherogenic activity seems especially promising, particularly for therapy of atherogenic dyslipidemia.

Research into the management of dyslipidaemia has increasingly focussed on the importance of high-density lipoprotein cholesterol (HDL-C) levels. It is well known that low levels of HDL are associated with an increased risk of cardiovascular events. Recent data have highlighted the anti-atherogenic actions of HDL such as anti-inflammatory, anti-oxidative activities, and of course, reverse cholesterol transport. This latter observation may explain certain effects on atherosclerotic plaques, in particular the observation that plaque regression can occur when treatments augment HDL-C levels. This review will outline the beneficial effects of HDL, along with the detrimental effects of other lipoproteins involved in atherosclerotic processes. This manuscript will also describe the therapeutic effects of nicotinic acid, a treatment that raises HDL-C levels. Studies show that using nicotinic acid as a monotherapy or in combination with other agents halts plaque progression and translates as a significant reduction in cardiovascular events.