Antonio J. Vallejo-Vaz

Familial hypercholesterolaemia: A global call to arms.

Familial Hypercholesterolaemia (FH) is the commonest autosomal co-dominantly inherited condition affecting man. It is caused by mutation in one of three genes, encoding the low-density lipoprotein (LDL) receptor, or the gene for apolipoprotein B (which is the major protein component of the LDL particle), or in the gene coding for PCSK9 (which is involved in the degradation of the LDL-receptor during its cellular recycling). These mutations result in impaired LDL metabolism, leading to life-long elevations in LDL-cholesterol (LDL-C) and development of premature atherosclerotic cardiovascular disease (ASCVD) [1], [2] and [3]. If left untreated, the relative risk of premature coronary artery disease is significantly higher in heterozygous patients than unaffected individuals, with most untreated homozygotes developing ASCVD before the age of 20 and generally not surviving past 30 years [2], [3], [4] and [5]. Although early detection and treatment with statins and other LDL-C lowering therapies can improve survival, FH remains widely underdiagnosed and undertreated [1], thereby representing a major global public health challenge.

Low-Density Lipoprotein Cholesterol Lowering for the Primary Prevention of Cardiovascular Disease Among Men With Primary Elevations of Low-Density Lipoprotein Cholesterol Levels of 190 mg/dL or Above: Analyses From the WOSCOPS (West of Scotland Coronary Prevention Study) 5-Year Randomized Trial and 20-Year Observational Follow-Up

Background: Patients with primary elevations of low-density lipoprotein cholesterol (LDL-C) ≥190 mg/dL are at a higher risk of atherosclerotic cardiovascular disease as a result of long-term exposure to markedly elevated LDL-C levels. Therefore, initiation of statin therapy is recommended for these individuals. However, there is a lack of randomized trial evidence supporting these recommendations in primary prevention. In the present analysis, we provide hitherto unpublished data on the cardiovascular effects of LDL-C lowering among a primary prevention population with LDL-C ≥190 mg/dL. Methods: We aimed to assess the benefits of LDL-C lowering on cardiovascular outcomes among individuals with primary elevations of LDL-C ≥190 mg/dL without preexisting vascular disease at baseline. We performed post hoc analyses from the WOSCOPS (West of Scotland Coronary Prevention Study) randomized, placebo-controlled trial, and observational posttrial long-term follow-up, after excluding individuals with evidence of vascular disease at baseline. WOSCOPS enrolled 6595 men aged 45 to 64 years, who were randomly assigned to pravastatin 40 mg/d or placebo. In the present analyses, 5529 participants without evidence of vascular disease were included, stratified by LDL-C levels into those with LDL-C <190 mg/dL (n=2969; mean LDL-C 178±6 mg/dL) and those with LDL-C ≥190 mg/dL (n=2560; mean LDL-C 206±12 mg/dL). The effect of pravastatin versus placebo on coronary heart disease and major adverse cardiovascular events were assessed over the 4.9-year randomized controlled trial phase and on mortality outcomes over a total of 20 years of follow-up. Results: Among 5529 individuals without vascular disease, pravastatin reduced the risk of coronary heart disease by 27% (P=0.002) and major adverse cardiovascular events by 25% (P=0.004) consistently among those with and without LDL-C ≥190 mg/dL (P-interaction >0.9). Among individuals with LDL-C ≥190 mg/dL, pravastatin reduced the risk of coronary heart disease by 27% (P=0.033) and major adverse cardiovascular events by 25% (P=0.037) during the initial trial phase and the risk of coronary heart disease death, cardiovascular death, and all-cause mortality by 28% (P=0.020), 25% (P=0.009), and 18% (P=0.004), respectively, over a total of 20 years of follow-up. Conclusions: The present analyses provide robust novel evidence for the short- and long-term benefits of lowering LDL-C for the primary prevention of cardiovascular disease among individuals with primary elevations of LDL-C ≥190 mg/dL.Background —Patients with primary elevations of LDL-C ≥190 mg/dL are at a higher risk of atherosclerotic cardiovascular disease as a result of long-term exposure to markedly elevated LDL-C levels. Therefore, initiation of statin therapy is recommended for these individuals. However, there is a lack of randomised trial evidence supporting these recommendations in primary prevention. In the present analysis we provide hitherto unpublished data on the cardiovascular effects of LDL-C lowering among a primary prevention population with LDL-C ≥190 mg/dL. Methods —We aimed to assess the benefits of LDL-C lowering on cardiovascular outcomes among individuals with primary elevations of LDL-C ≥190 mg/dL without pre-exiting vascular disease at baseline. We carried out post-hoc analyses from the West Of Scotland Coronary Prevention Study (WOSCOPS) randomised, placebo-controlled trial, and observational post-trial long-term follow-up, after excluding individuals with evidence of vascular disease at baseline. WOSCOPS enrolled 6595 men aged 45-64 years, who were randomised to pravastatin 40 mg/d or placebo. In the present analyses, 5529 participants without evidence of vascular disease were included, stratified by LDL-C levels into those with LDL-C Results —Among 5529 individuals without vascular disease, pravastatin reduced the risk of CHD by 27% (p=0.002) and MACE by 25% (p=0.004) consistently among those with and without LDL-C ±190 mg/dL (p-interaction >0.9). Among individuals with LDL-C ±190 mg/dL, pravastatin reduced the risk of CHD by 27% (p=0.033) and MACE by 25% (p=0.037) during the initial trial phase and the risk of CHD death, cardiovascular death and all-cause mortality by 28% (p=0.020), 25% (p=0.009) and 18% (p=0.004), respectively, over a total of 20-years of follow-up. Conclusions —The present analyses provide robust novel evidence for the short and long-term benefits of lowering LDL-C for the primary prevention of cardiovascular disease among individuals with primary elevations of LDL-C ±190 mg/dL.

Pooling and expanding registries of familial hypercholesterolaemia to assess gaps in care and improve disease management and outcomes: Rationale and design of the global EAS Familial Hypercholesterolaemia Studies Collaboration

BACKGROUND The potential for global collaborations to better inform public health policy regarding major non-communicable diseases has been successfully demonstrated by several large-scale international consortia. However, the true public health impact of familial hypercholesterolaemia (FH), a common genetic disorder associated with premature cardiovascular disease, is yet to be reliably ascertained using similar approaches. The European Atherosclerosis Society FH Studies Collaboration (EAS FHSC) is a new initiative of international stakeholders which will help establish a global FH registry to generate large-scale, robust data on the burden of FH worldwide. METHODS The EAS FHSC will maximise the potential exploitation of currently available and future FH data (retrospective and prospective) by bringing together regional/national/international data sources with access to individuals with a clinical and/or genetic diagnosis of heterozygous or homozygous FH. A novel bespoke electronic platform and FH Data Warehouse will be developed to allow secure data sharing, validation, cleaning, pooling, harmonisation and analysis irrespective of the source or format. Standard statistical procedures will allow us to investigate cross-sectional associations, patterns of real-world practice, trends over time, and analyse risk and outcomes (e.g. cardiovascular outcomes, all-cause death), accounting for potential confounders and subgroup effects. CONCLUSIONS The EAS FHSC represents an excellent opportunity to integrate individual efforts across the world to tackle the global burden of FH. The information garnered from the registry will help reduce gaps in knowledge, inform best practices, assist in clinical trials design, support clinical guidelines and policies development, and ultimately improve the care of FH patients.

Fibrate therapy and flow-mediated dilation: A systematic review and meta-analysis of randomized placebo-controlled trials

Flow-mediated dilation (FMD) of the brachial artery reflects endothelium-dependent vasodilator function; since it correlates with coronary endothelial function, its reduction could predict cardiovascular events. Several studies have investigated the potential impact of fibrates therapy on endothelial function, but clinical findings have not been fully consistent. We aimed to conduct a meta-analysis of randomized placebo-controlled trials in order to clarify whether fibrate therapy could improve endothelial function. A systematic search in PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases was performed to identify randomized placebo-controlled trials investigating the effect of fibrates on endothelial function as estimated by FMD. A random-effects model and generic inverse variance method were used for meta-analysis. Sensitivity analysis, risk of bias evaluation, and publication bias assessment were carried out using standard methods. Random-effects meta-regression was used to evaluate the impact of treatment duration on the estimated effect size. Fifteen trials with a total of 556 subjects met the eligibility criteria. Fibrate therapy significantly improves FMD (weighted mean difference [WMD]: 1.64%, 95% CI: 1.15, 2.13, p<0.001) and the result was confirmed in both subgroups with treatment durations ≤8 weeks (WMD: 1.35%, 95% CI: 0.85, 1.86, p<0.001) and >8 weeks (WMD: 2.55%, 95% CI: 1.21, 3.89, p<0.001). When the analysis was stratified according to the fibrate type, a significant effect was observed with fenofibrate but not with gemfibrozil, though difference between the two subgroups was not significant. Meta-analysis of data from trials where nitrate mediated dilation (NMD) was available did not suggest a significant change in NMD following treatment with fibrates. The results of this meta-analysis suggest that fibrates may exert beneficial effects on endothelial function, even over a short-term treatment course.

Total and Fetal Circulating Cell-Free DNA, Angiogenic, and Antiangiogenic Factors in Preeclampsia and HELLP Syndrome

BACKGROUND Preeclampsia (PE) is a hypertensive disorder of pregnancy characterized by hypertension and proteinuria. The HELLP syndrome is the most severe form of PE. The aim of the present study was to determine different potential biomarkers that may help us perform an early diagnosis of the disease, assess on the severity of the disease, and/or predict maternal or fetal adverse outcomes. METHODS We measured serum levels of total and fetal circulating cell-free DNA (cfDNA), soluble endoglin, soluble form of vascular endothelial growth factor receptor, and placental growth factor in a healthy control group of pregnant women (n = 26), patients with mild (n = 37) and severe PE (n = 25), and patients with HELLP syndrome (n = 16). RESULTS We observed a gradual and strong relationship between all the biomarkers mentioned and the range of severity of PE, with the highest levels in patients with HELLP syndrome. Nevertheless, only the values of total cfDNA were able to significantly differentiate severe PE and HELLP syndrome (20957 ± 2784 vs. 43184 ± 8647 GE/ml, P = 0.01). Receiver operating characteristic (ROC) curves were constructed (i) for the healthy group with respect to the groups with PE and (ii) for patients with PE with respect to the group with HELLP syndrome; sensitivity and specificity values at different cutoff levels were calculated in each case. The maximum ROC area under the curve value for PE and HELLP syndrome (with respect to controls) was 0.91 (P < 0.001). CONCLUSIONS The measured biomarkers of cell damage, angiogenesis, and antiangiogenesis may reflect the severity of PE, with higher levels in patients who develop HELLP syndrome. In addition, these biomarkers may also help predict adverse fetal and maternal outcomes.

Cholesterol Efflux Capacity as a Novel Biomarker for Incident Cardiovascular Events Has High-Density Lipoprotein Been Resuscitated?

HDL cholesterol efflux capacity and incident cardiovascular events Rohatgi et al N Engl J Med 2014;371:2383–2393. Although low levels of high-density lipoprotein cholesterol (HDL-C) represent a strong independent risk marker inversely associated with cardiovascular disease (CVD), large interventional trials have failed to translate the increases in HDL-C into reductions in cardiovascular events. As HDL plasma levels represent a pool of the different HDL subfractions, which may vary in their structure and function, its levels may not capture adequately the dynamic process of reverse cholesterol transport. This has led attention to be focused on markers of HDL function, for example, cholesterol efflux capacity, further supported by a recent population-based cohort study that has related it with incident atherosclerotic cardiovascular events, suggesting HDL hypothesis may need to be revisited. HDL particles are responsible for the reverse cholesterol transport, the physiological mechanism by which the cholesterol in peripheral tissues and cells is transferred to the liver for biliary excretion.1,2 Reverse cholesterol transport is considered an important atheroprotective mechanism because it facilitates the removal of excess cholesterol from lipid-laden macrophages in the arterial wall and the subsequent reduction in the proinflammatory responses; in its first steps, the reverse cholesterol transport requires HDL particles to act as extracellular acceptors of cholesterol from these cells.1,2 The cholesterol efflux capacity (CEC), that is, the ability of HDL particles to accept cholesterol esters from cholesterol-loaded macrophages, represents, therefore, a key process within the mechanism of reverse cholesterol transport.1,2 In animal models, cholesterol efflux can modulate the severity of atherosclerosis, and in humans, CEC has been related to prevalent coronary artery disease independently of HDL-C levels in cross-sectional studies.3 In a recent article published by Rohatgi et al in the New England Journal of Medicine , CEC was for …

Triglyceride-Rich Lipoprotein Cholesterol and Risk of Cardiovascular Events Among Patients Receiving Statin Therapy in the Treating to New Targets (TNT) Trial

Background: Mendelian randomization data suggest that the genetic determinants of lifetime higher triglyceride-rich lipoprotein-cholesterol (TRL-C) are causally related to cardiovascular disease and therefore a potential therapeutic target. The relevance of TRL-C among patients receiving statins is unknown. We assessed the relationship between TRL-C and cardiovascular risk, and whether this risk was modifiable among patients receiving statins in the TNT trial (Treating to New Targets). Methods: Patients with coronary heart disease and low-density lipoprotein cholesterol (LDL-C) 130 to 250 mg/dL entered an 8-week run-in phase with atorvastatin 10 mg/d (ATV10). After this period, participants with LDL-C <130 mg/dL entered the randomized phase with ATV10 (n=5006) versus atorvastatin 80 mg/d (ATV80, n=4995). The primary end point was coronary heart disease death, nonfatal myocardial infarction, resuscitated cardiac arrest, or stroke (major adverse cardiovascular events [MACE]). TRL-C was calculated as total cholesterol minus high-density lipoprotein cholesterol minus LDL-C. The effect of atorvastatin on TRL-C was assessed during the run-in phase (ATV10) and randomized phase (ATV80 versus ATV10). The risk of MACE was assessed across quintiles (Q) of baseline TRL-C (and, for comparison, by baseline triglycerides and non–high-density lipoprotein cholesterol) during the randomized period. Last, the association between TRL-C changes with atorvastatin and cardiovascular risk was assessed by multivariate Cox regression. Results: ATV10 reduced TRL-C 10.7% from an initial TRL-C of 33.9±16.6 mg/dL. ATV80 led to an additional 15.4% reduction. Cardiovascular risk factors positively correlated with TRL-C. Among patients receiving ATV10, higher TRL-C was associated with higher 5-year MACE rates (Q1=9.7%, Q5=13.8%; hazard ratio Q5-versus-Q1, 1.48; 95% confidence interval, 1.15–1.92; P-trend<0.0001). ATV80 (versus ATV10) did not significantly alter the risk of MACE in Q1-Q2, but significantly reduced risk in Q3-Q5 (relative risk reduction, 29%–41%; all P<0.0250), with evidence of effect modification (P-homogeneity=0.0053); results were consistent for triglycerides (P-homogeneity=0.0101) and directionally similar for non–high-density lipoprotein cholesterol (P-homogeneity=0.1387). Last, in adjusted analyses, a 1 SD percentage reduction in TRL-C with atorvastatin resulted in a significant lower risk of MACE (hazard ratio, 0.93; 95% confidence interval, 0.86–1.00; P=0.0482) independent of the reduction in LDL-C and of similar magnitude to that per 1 SD lowering in LDL-C (hazard ratio, 0.89; 95% confidence interval, 0.83–0.95; P=0.0008). Conclusions: The present post hoc analysis from TNT shows that increased TRL-C levels are associated with an increased cardiovascular risk and provides evidence for the cardiovascular benefit of lipid lowering with statins among patients who have coronary heart disease with high TRL-C. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT00327691.

Epidemiology of familial hypercholesterolaemia: Community and clinical

Familial hypercholesterolaemia (FH) is a genetic disorder affecting the metabolism of low-density lipoprotein (LDL) particles, leading to high LDL-cholesterol levels maintained over time and higher risk of cardiovascular disease (CVD) early in life. Contemporary studies have challenged prior estimations of FH prevalence and suggest this condition to be more frequent than previously considered, with an overall prevalence rate of 1:200-300 individuals in the general population (1:160,000-300,000 for homozygous FH). However, prevalence of FH varies around the world. In part this is due to an artefact of approaches of detection and methods used to diagnose FH (e.g. lack of gold standard for diagnosis of FH, different criteria applied, availability of genetic testing). But also due to intrinsic characteristic of different populations, e.g. higher presence of founder effects or rates of consanguinity. Additionally, results from many regions are lacking and it is estimated that only a small percentage of subjects with FH would have been diagnosed overall. FH entails a significantly higher risk of CVD, reported to be higher than that estimated by conventional risk assessment tools for the general population. This risk is mainly driven by coronary heart disease. Despite this evidence, low rates of patients meet therapeutic targets for cardiovascular prevention, and implementation of therapy (high intensity statins, combination therapy) is needed. The introduction of novel lipid-lowering therapies may improve this situation. In the present review, we discuss the epidemiology of FH overall, with special attention to different aspects related to prevalence, cardiovascular risk and prognosis, and treatment of FH.

Promoting high-density lipoprotein function via intravenous infusion: the rebirth of apoA-I Milano?

This editorial refers to ‘A single infusion of MDCO-216 (ApoA-I Milano/POPC) increases ABCA1-mediated cholesterol efflux and pre-beta 1 HDL in healthy volunteers and patients with stable coronary artery disease’, by D.G. Kallend et al. , on page 23. Apolipoprotein A-I (apoA-I) is the major protein component of the high-density lipoprotein (HDL) particles. Higher levels of apoA-I have been associated with a lower cardiovascular risk even among subjects with reduced low-density lipoprotein cholesterol (LDL-C) levels;1,2 but, unlike HDL-C, an increase in apoA-I levels in individuals treated with statins has been associated with a lower risk of major cardiovascular events.2 These and other data have encouraged investigations of apoA-I mimetic compounds or reconstituted HDL particles as a potential therapeutic strategy. ApoA-I Milano (apoA-IM) is a natural variant of human apoA-I identified in individuals in northern Italy, which results from the replacement of arginine by cysteine at position 173 of the apoA-I amino acid sequence;3 this variation introduces structural changes in apoA-I, allows the formation of apoA-I homodimers (A-IM/A-IM) and heterodimers with apoA-II, and alters the apoA-I properties, which ultimately may affect HDL function.3 The carriers of this variant usually exhibit a lipid phenotype consistent of …

Overview of the current status of familial hypercholesterolaemia care in over 60 countries - The EAS Familial Hypercholesterolaemia Studies Collaboration (FHSC)

BACKGROUND AND AIMS Management of familial hypercholesterolaemia (FH) may vary across different settings due to factors related to population characteristics, practice, resources and/or policies. We conducted a survey among the worldwide network of EAS FHSC Lead Investigators to provide an overview of FH status in different countries. METHODS Lead Investigators from countries formally involved in the EAS FHSC by mid-May 2018 were invited to provide a brief report on FH status in their countries, including available information, programmes, initiatives, and management. RESULTS 63 countries provided reports. Data on FH prevalence are lacking in most countries. Where available, data tend to align with recent estimates, suggesting a higher frequency than that traditionally considered. Low rates of FH detection are reported across all regions. National registries and education programmes to improve FH awareness/knowledge are a recognised priority, but funding is often lacking. In most countries, diagnosis primarily relies on the Dutch Lipid Clinics Network criteria. Although available in many countries, genetic testing is not widely implemented (frequent cost issues). There are only a few national official government programmes for FH. Under-treatment is an issue. FH therapy is not universally reimbursed. PCSK9-inhibitors are available in ∼2/3 countries. Lipoprotein-apheresis is offered in ∼60% countries, although access is limited. CONCLUSIONS FH is a recognised public health concern. Management varies widely across countries, with overall suboptimal identification and under-treatment. Efforts and initiatives to improve FH knowledge and management are underway, including development of national registries, but support, particularly from health authorities, and better funding are greatly needed.