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 LDL­C 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.

The challenge of choosing in cardiovascular risk management.

Cardiovascular disease (CVD) is a major cause of morbidity and mortality worldwide. For many years guidelines have listed optimal preventive therapy. More recently, novel therapeutic options have broadened the options for state-of-the-art CV risk management (CVRM). In the majority of patients with CVD, risk lowering can be achieved by utilising standard preventive medication combined with lifestyle modifications. In a minority of patients, add-on therapies should be considered to further reduce the large residual CV risk. However, the choice of which drug combination to prescribe and in which patients has become increasingly complicated, and is dependent on both the absolute CV risk and the reason for the high risk. In this review, we discuss therapeutic decisions in CVRM, focusing on (1) the absolute CV risk of the patient and (2) the pros and cons of novel treatment options.

From evidence to practice: development of web-based Dutch lipid reference values.

INTRODUCTION: In the Netherlands, the total number of yearly measured lipid profiles exceeds 500,000. While lipid values are strongly affected by age and sex, until recently, no up-to-date age- and sex-specific lipid reference values were available. We describe the translation of big-cohort lipid data into accessible reference values, which can be easily incorporated in daily clinical practice. METHODS: Lipid values (total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides) from all healthy adults and children in the LifeLines cohort were used to generate age- and sex-specific percentiles. A combination of RStudio, Cascading Style Sheets and HyperText Markup Language was used to interactively display the percentiles in a responsive web layout. RESULTS: After exclusion of subjects reporting cardiovascular disease or lipid-lowering therapy at baseline, 141,611 subjects were included. On the website, input fields were created for age, sex and all main plasma lipids. Upon input of these values, corresponding percentiles are calculated, and output is displayed in a table and an interactive graph for each lipid. The website has been made available in both Dutch and English and can be accessed at www.lipidtools.com . CONCLUSION: We constructed the first searchable, national lipid reference value tool with graphical display in the Netherlands to use in screening for dyslipidaemias and to reduce the underuse of lipid-lowering therapy in Dutch primary prevention. This study illustrates that data collected in big-cohort studies can be made easily accessible with modern digital techniques and preludes the digital health revolution yet to come.

Two novel mutations in apolipoprotein C3 underlie atheroprotective lipid profiles in families.

Apolipoprotein C3 (APOC3) mutations carriers typically display high plasma high-density lipoprotein cholesterol (HDL-C) and low triglycerides (TGs). We set out to investigate the prevalence and clinical consequences of APOC3 mutations in individuals with hyperalphalipoproteinemia. Two novel mutations (c.-13-2A>G and c.55+1G>A) and one known mutation (c.127G>A;p.Ala43Thr) were found. Lipid profiles and apoCIII isoform distributions were measured. c.55+1G>A mutation carriers displayed higher HDL-C percentiles (35.6 ± 35.8 vs 99.0 ± 0, p = 0.002) and lower TGs (0.51 (0.37-0.61) vs 1.42 (1.12-1.81) mmol/l, p = 0.007) and apoCIII levels (4.24 ± 1.57 vs 7.33 ± 3.61 mg/dl, p = 0.18). c.-13-2A>G mutation carriers did not display significantly different HDL-C levels (84.0 ± 30.0 vs 63.7 ± 45.7, p = 0.50), a trend towards lower TGs [0.71 (0.54 to 0.78) vs 0.85 (0.85 to -) mmol/l, p = 0.06] and significantly lower apoCIII levels (3.09 ± 1.08 vs 11.45 ± 1.06 mg/dl, p = 0.003). p.Ala43Thr mutation carriers displayed a trend towards higher HDL-C percentiles (91.2 ± 31.8 vs 41.0 ± 29.7 mmol/l, p = 0.06) and significantly lower TGs [0.58 (0.36-0.63) vs 0.95 (0.71-1.20) mmol/l, p = 0.02] and apoCIII levels (4.92 ± 2.33 vs 6.60 ± 1.60, p = 0.25). Heterozygosity for APOC3 mutations results in high HDL-C and low TGs and apoCIII levels. This favourable lipid profile in patients with genetically low apoCIII levels holds promise for current studies investigating the potential of apoCIII inhibition as a novel therapeutic in cardiovascular disease prevention.

Mutations in LPL, APOC2, APOA5, GPIHBP1 and LMF1 in patients with severe hypertriglyceridaemia.

OBJECTIVES: The severe forms of hypertriglyceridaemia (HTG) are caused by mutations in genes that lead to the loss of function of lipoprotein lipase (LPL). In most patients with severe HTG (TG > 10 mmol L(-1) ), it is a challenge to define the underlying cause. We investigated the molecular basis of severe HTG in patients referred to the Lipid Clinic at the Academic Medical Center Amsterdam. METHODS: The coding regions of LPL, APOC2, APOA5 and two novel genes, lipase maturation factor 1 (LMF1) and GPI-anchored high-density lipoprotein (HDL)-binding protein 1 (GPIHBP1), were sequenced in 86 patients with type 1 and type 5 HTG and 327 controls. RESULTS: In 46 patients (54%), rare DNA sequence variants were identified, comprising variants in LPL (n = 19), APOC2 (n = 1), APOA5 (n = 2), GPIHBP1 (n = 3) and LMF1 (n = 8). In 22 patients (26%), only common variants in LPL (p.Asp36Asn, p.Asn318Ser and p.Ser474Ter) and APOA5 (p.Ser19Trp) could be identified, whereas no mutations were found in 18 patients (21%). In vitro validation revealed that the mutations in LMF1 were not associated with compromised LPL function. Consistent with this, five of the eight LMF1 variants were also found in controls and therefore cannot account for the observed phenotype. CONCLUSIONS: The prevalence of mutations in LPL was 34% and mostly restricted to patients with type 1 HTG. Mutations in GPIHBP1 (n = 3), APOC2 (n = 1) and APOA5 (n = 2) were rare but the associated clinical phenotype was severe. Routine sequencing of candidate genes in severe HTG has improved our understanding of the molecular basis of this phenotype associated with acute pancreatitis and may help to guide future individualized therapeutic strategies.

Extreme xanthomatosis in patients with both familial hypercholesterolemia and cerebrotendinous xanthomatosis.

Two unrelated individuals were referred to Lipid Clinics in The Netherlands and Chile with extreme xanthomatosis and hypercholesterolemia. Both were diagnosed with heterozygous familial hypercholesterolemia (heFH) after molecular genetic analysis of the low-density lipoprotein (LDL) receptor gene. Since heFH by itself could not account for the massive xanthomas, the presence of an additional hereditary lipid or lipoprotein disorder was suspected. Further genetic analysis revealed homozygozity for mutations in the sterol 27-hydroxylase gene, confirming the diagnosis of cerebrotendinous xanthomatosis (CTX). Markedly, the typical neurological manifestations of CTX were absent, suggestive of a protective role of LDL-receptor deficiency against the severe neurological consequences of CTX.

Effect of sulodexide on endothelial glycocalyx and vascular permeability in patients with type 2 diabetes mellitus.

AIMS/HYPOTHESIS: Endothelial glycocalyx perturbation contributes to increased vascular permeability. In the present study we set out to evaluate whether: (1) glycocalyx is perturbed in individuals with type 2 diabetes mellitus, and (2) oral glycocalyx precursor treatment improves glycocalyx properties. METHODS: Male participants with type 2 diabetes (n = 10) and controls (n = 10) were evaluated before and after 2 months of sulodexide administration (200 mg/day). The glycocalyx dimension was estimated in two different vascular beds using sidestream dark field imaging and combined fluorescein/indocyanine green angiography for sublingual and retinal vessels, respectively. Transcapillary escape rate of albumin (TER(alb)) and hyaluronan catabolism were assessed as measures of vascular permeability. RESULTS: Both sublingual dimensions (0.64 [0.57-0.75] µm vs 0.78 [0.71-0.85] µm, p < 0.05, medians [interquartile range]) and retinal glycocalyx dimensions (5.38 [4.88-6.59] µm vs 8.89 [4.74-11.84] µm, p < 0.05) were reduced in the type 2 diabetes group compared with the controls whereas TER(alb) was increased (5.6 ± 2.3% vs 3.7 ± 1.7% in the controls, p < 0.05). In line with these findings, markers of hyaluronan catabolism were increased with diabetes (hyaluronan 137 ± 29 vs 81 ± 8 ng/ml and hyaluronidase 78 ± 4 vs 67 ± 2 U/ml, both p < 0.05). Sulodexide increased both the sublingual and retinal glycocalyx dimensions in participants with diabetes (to 0.93 [0.83-0.99] µm and to 5.88 [5.33-6.26] µm, respectively, p < 0.05). In line, a trend towards TER(alb) normalisation (to 4.0 ± 2.3%) and decreases in plasma hyaluronidase (to 72 ± 2 U/ml, p < 0.05) were observed in the diabetes group. CONCLUSION/INTERPRETATION: Type 2 diabetes is associated with glycocalyx perturbation and increased vascular permeability, which are partially restored following sulodexide administration. Further studies are warranted to determine whether long-term treatment with sulodexide has a beneficial effect on cardiovascular risk. TRIAL REGISTRATION: www.trialregister.nl NTR780/ http://isrctn.org ISRCTN82695186 FUNDING: An unrestricted Novartis Foundation for Cardiovascular Excellence grant (2006) to M. Nieuwdorp/E. S. G. Stroes, Dutch Heart Foundation (grant number 2005T037).

[Anti-inflammatory therapy in cardiovascular disease; from hypothesis to future guideline?] / Anti-inflammatoire therapie bij hart- en vaatziekten.

Atherosclerosis is a lipid-driven inflammatory disease, in which both lipids and inflammation can be considered treatment targets. The CANTOS-trial, using the IL-1ß monoclonal antibody canakinumab, has proven the concept of targeting inflammation to reduce cardiovascular risk. In contrast, the anti-inflammatory drug methotrexate failed to show cardiovascular benefit. Colchicine is a drug used in gout patients, acting as a non-selective inflammasome inhibitor. The COLCOT-trial uncovered a significant reduction in ischemic cardiovascular events in subjects following an acute myocardial infarction, which was recently confirmed in the larger LoDoCo2-trial in stable coronary heart disease. Guideline committees will have to decide whether the trials have supplied sufficient evidence to implement the routine use of colchicine in the guidelines for cardiovascular risk management. These convincing endpoint trials have paved the way for tailored treatment regimens, comprising anti-inflammatory agents besides currently established treatment modalities in CVRM.

Targeting apoC-III and ANGPTL3 in the treatment of hypertriglyceridemia.

INTRODUCTION: The prevalence of hypertriglyceridemia (HTG) is increasing. Elevated triglyceride (TG) levels are associated with an increased cardiovascular disease (CVD) risk. Moreover, severe HTG results in an elevated risk of pancreatitis, especially in severe HTG with an up to 350-fold increased risk. Both problems emphasize the clinical need for effective TG lowering. AREAS COVERED: The purpose of this review is to discuss the currently available therapies and to elaborate the most promising novel therapeutics for TG lowering. EXPERT OPINION: Conventional lipid lowering strategies do not efficiently lower plasma TG levels, leaving a residual CVD and pancreatitis risk. Both apolipoprotein C-III (apoC-III) and angiopoietin-like 3 (ANGPTL3) are important regulators in TG-rich lipoprotein (TRL) metabolism. Several novel agents targeting these linchpins have ended phase II/III trials. Volanesorsen targeting apoC-III has shown reductions in plasma TG levels up to 90%. Multiple ANGPLT3 inhibitors (evinacumab, IONIS-ANGPTL3-LRx, ARO-ANG3) effectuate TG reductions up to 70% with concomitant potent reduction in all other apoB containing lipoprotein fractions. We expect these therapeutics to become players in the treatment for (especially) severe HTG in the near future.

Combination statin-fibrate therapy: safety aspects.

Patients with type 2 diabetes or metabolic syndrome remain at high residual risk of cardiovascular events even after intensive statin therapy. While treatment guidelines recommend the addition of a fibrate to statin therapy in this setting, concerns about the potential for myopathy may limit the use of this combination in clinical practice. These concerns are certainly justified for gemfibrozil, which interferes with statin glucuronidation, leading to elevation in statin plasma concentrations and an increased risk of myotoxicity in combination with a range of commonly prescribed statins. However, the available evidence refutes suggestions that this is a class effect for fibrates. Fenofibrate does not adversely influence the metabolism or pharmacokinetics of any of the commonly prescribed statins. This in turn translates to a reduced potential for myotoxicity in combination with a statin. Data are awaited from the ongoing Action to Control Cardiovascular Risk in Diabetes (ACCORD) study to evaluate the efficacy and safety of fenofibrate plus simvastatin combination therapy in type 2 diabetes patients.

Systemic inflammation as a risk factor for atherothrombosis.

Several chronic inflammatory disorders, such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA), and chronic infections that are associated with a chronic inflammatory state, such as human immunodeficiency virus (HIV) infection, are associated with an increased incidence of cardiovascular disease (CVD). Cardiovascular mortality is a major cause of death in patients with these disorders. Direct effects and indirect sequelae of systemic inflammation promote atherothrombotic vascular disease. Pathophysiological processes promoting atherogenesis can initiate years before the diagnosis of a chronic inflammatory disease is made, and since exposure to risk factors in this pre-clinical phase is widespread, early cardiovascular protection in these patients seems warranted.

Increases in myeloperoxidase levels after exercise in myocardial perfusion scintigraphy are not induced by myocardial ischemia.

BACKGROUND: Increased systemic levels of myeloperoxidase (MPO) have been reported in patients with acute myocardial ischemia. We studied the association between exercise-induced myocardial ischemia measured by myocardial perfusion scintigraphy (MPS) and the magnitude and time course of changes in MPO levels in humans. METHODS: One hundred and twenty six patients underwent symptom limited exercise MPS. Myocardial ischemia was assessed semi-quantitatively. Plasma samples were taken before the start of exercise (baseline), at maximum exercise and every hour up to 6 h after maximum exercise. RESULTS: Myocardial ischemia was present in 42 (33%) patients. MPO levels rapidly increased during exercise in patients with and without ischemia (to 131% (106-172%) and 145% (121-199%) of baseline, respectively). MPO levels and absolute changes in MPO did not differ between patients with and without ischemia at any time point. None of the patient characteristics, including presence of ischemia, was independently predictive of the absolute increase in MPO levels during exercise. CONCLUSIONS: Exercise related immediate increases in MPO levels do not reflect myocardial ischemia.

[The role of the high-density lipoprotein (HDL) particle in atherogenesis and potential methods to increase HDL concentrations]. / De rol van het 'high-density'-lipoproteine (HDL)-partikel in de atherogenese en de mogelijkheden om de concentratie daarvan te verhogen.

The concentration of high-density lipoprotein (HDL) cholesterol has a strong inverse relationship to the incidence of cardiovascular disease. The protective effect of HDL cholesterol is due not only to its promotion of reverse cholesterol transport from the vascular wall to the liver, but also to its anti-inflammatory, antioxidative and antithrombotic effects. Patients with low HDL cholesterol concentrations are at increased risk for cardiovascular disease and may be considered for treatment with lipid-lowering drugs, such as statins, niacin and fibrates. Currently, only a limited number of HDL-increasing agents have demonstrated beneficial effects of increasing HDL in studies with intermediary endpoints. Among these drugs are apolipoprotein A-1 variants, inhibitors of the cholesterol ester transfer protein JTT-705 and torcetrapib.

Gene therapy for genetic lipoprotein lipase deficiency: from promise to practice.

Lipoprotein lipase (LPL) deficiency is a rare, hereditary disorder of lipoprotein metabolism characterised by severely increased triglyceride levels, and associated with an increased risk for pancreatitis. Since no adequate treatment modality is available for this disorder, we set out to develop an LPL gene therapy protocol. This paper focuses on the clinical presentation of LPL deficiency, summarises the preclinical investigations in animal models and describes the rationale to evaluate gene therapy for this monogenetic disorder of lipid metabolism in humans.

Increasing HDL cholesterol with extended-release nicotinic acid: from promise to practice.

BACKGROUND: The inverse relation between high-density lipoprotein cholesterol (HDL-C) and cardiovascular (CV) disease underscores the need for clinical evaluation of the effect of HDL-C increasing drugs on the prevalence of CV disease. METHODS: We review the efficacy of Niaspan on serum lipids and the occurrence of side effects either alone or in combination with statins, in randomised controlled trials (RCT) and comparative cohort trials (CCT). RESULTS: In four RCTs, low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and lipoprotein(a) (Lp(a)) were decreased by 13, 26, and 17%, respectively, whereas HDL-C increased by 18%. In four CCTs a combination of Niaspan and statins showed an additional 22% reduction in LDL-C, 8% in TG and 6% in Lp(a) levels, compared with Niaspan monotherapy. Statin therapy had a minor additional effect of 1% on a total of 25% HDL-C increase during Niaspan treatment. Flushes occurred in 69% of the patients without any additional toxicity during combination therapy. CONCLUSION: Niaspan effectively raises HDL-C with concomitant beneficial effects on TG and LDL-C. Niaspan can be combined safely with statins and is also effective in patients with combined dyslipidaemia and type 2 diabetes mellitus. Trials on CV endpoints evaluating the effect of statins with Niaspan are urgently needed to settle whether this combination can confirm the high expectations for cardiovascular outcome.

The promise of cholesteryl ester transfer protein (CETP) inhibition in the treatment of cardiovascular disease.

There is a strong need to reduce the risk of cardiovascular disease (CVD) beyond the use of statins that lower low-density lipoprotein cholesterol (LDL-C). The inverse relationship of high-density lipoprotein cholesterol (HDL-C) with cardiovascular disease suggests HDL-C raising therapy as a novel target. This review discusses the role of HDL-C in atherogenesis as well as the promise of cholesteryl ester transfer protein (CETP) inhibition in CVD prevention. While genetic studies show conflicting results on correlations between HDL-C and CVD, experimental studies have yielded sufficient encouraging data to proceed with the development of HDL-C raising strategies. CETP inhibition has been shown to successfully increase HDL-C levels in man. However, the first CETP inhibitor tested in phase III trials increased mortality possibly due to torcetrapib-specific vasopressor effects. More recently, dalcetrapib did not show an effect on CVD outcome while raising HDL-C by 30%, thereby refuting the HDL-C hypothesis. Anacetrapib and evacetrapib are currently tested in phase III clinical trials and have not shown adverse effects thus far. Both compounds not only increase HDL-C by 129-151%, they also decrease LDL-C (36-41%) and anacetrapib lowers Lp(a) (17%). Combined, these effects are anticipated to decrease CVD risk and the results will be revealed in 2017.

Antisense oligonucleotides in the treatment of lipid disorders: pitfalls and promises.

Dyslipidaemia is one of the pivotal risk factors for cardiovascular disease (CVD), and lipid-lowering therapy is therefore the cornerstone in cardiovascular risk management. With the currently available treatment options the relative risk reduction in CVD is approximately 30%, leaving a large residual risk. This calls for the development of additional therapeutic moieties and antisense oligonucleotides (ASOs) have proven to be such a new and effective treatment. ASOs are short single strands of DNA that intracellularly bind mRNA of specific proteins. This induces the degradation of the mRNA through which the protein cannot be produced. Based on knowledge of lipid metabolism several targets of ASO therapy can be identified. This review offers a summary of current developments in ASO therapy regarding lipid disorders.

Intestinal cholesterol secretion: future clinical implications.

Together with the liver, the intestine serves as a homeostatic organ in cholesterol metabolism. Recent evidence has substantiated the pivotal role of the intestine in reverse cholesterol transport (RCT). RCT is a fundamental antiatherogenic pathway, mediating the removal of cholesterol from tissues in the body to the faeces. In humans, faecal cholesterol elimination via the RCT pathway is considered to be restricted to excretion via the hepatobiliary route. Recently, however, direct trans-intestinal excretion of plasma-derived cholesterol (TICE) was shown to contribute substantially to faecal neutral sterol (FNS) excretion in mice. TICE was found to be amenable to stimulation by various pharmacological and dietary interventions in mice, offering new options to target the intestine as an inducible, cholesterol-excretory organ. The relevance of TICE for cholesterol elimination in humans remains to be established. There is, however, emerging evidence for the presence of TICE in human (patho) physiology. This review discusses our current understanding of TICE and its novel therapeutic potential for individuals at increased risk of cardiovascular disease.

Critical determinants of cardiovascular risk in rheumatoid arthritis.

Rheumatoid arthritis (RA), a prototypical immune-mediated inflammatory disease, is characterized by increased cardiovascular morbidity and mortality, independent from the established cardiovascular risk factors. The chronic inflammatory state, a hallmark of RA, is considered to be a driving force for accelerated atherogenesis. Concurrent conditions that expedite the atherosclerotic process in RA involve endothelial dysfunction, dyslipidemia and procoagulant changes. These facilitating states can be reversed by retraction of the systemic inflammatory activity. Consequently, aggressive control of disease activity has been suggested to be instrumental for cardiovascular risk reduction. In the present review, we focus on these critical determinant that promote premature atherosclerosis in RA.