Targeting LDL: is lower better and is it safe?

Trends and Disparities in Treatment and Control of Atherosclerotic Cardiovascular Disease in US Adults, 1999 to 2018

BACKGROUND

Although cardiovascular mortality continued declining from 2000 to 2019, the rate of this decrease decelerated. We aimed to assess the trends and disparities in risk factor control and treatment among US adults with atherosclerotic cardiovascular disease to find potential causes of the deceleration.

METHODS AND RESULTS

A total of 55 ,021 participants, aged ≥20 years, from the 1999 to 2018 National Health and Nutrition Examination Survey were included, of which 5717 were with atherosclerotic cardiovascular disease. Risk factor control was defined as hemoglobin A1c <7%, blood pressure <140/90 mm Hg, and non-high-density lipoprotein cholesterol <100 mg/dL. The prevalence of atherosclerotic cardiovascular disease oscillated between 7.3% and 8.9% from 1999 to 2018. A significant increasing trend was observed in the prevalence of diabetes, obesity, heavy alcohol consumption, and self-reported hypertension within the population with atherosclerotic cardiovascular disease (Ptrend≤0.001). Non-high-density lipoprotein cholesterol <100 mg/dL increased from 7.1% in 1999 to 2002 to 15.7% in 2003 to 2006, before plateauing. Blood pressure control (<140/90 mm Hg) increased until 2011 to 2014, but declined to 70.1% in 2015 to 2018 (Ptrend<0.001, Pjoinpoint=0.14). Similarly, the proportion of participants achieving hemoglobin A1c control began to decrease after 2006 (Pjoinpoint=0.05, Ptrend=0.001). The percentage of participants achieving all 3 targets increased significantly from 4.5% to 18.6% across 1999 to 2018 (Ptrend=0.02), but the increasing trend decelerated after 2005 to 2006 (Pjoinpoint<0.001). Striking disparities in risk factor control and medication use persisted between sexes, and between different racial and ethnic populations.

CONCLUSIONS

Worsened control of glycemia, blood pressure, obesity, and alcohol consumption, leveled lipid control, and persistent socioeconomic disparities may be contributing factors to the observed deceleration in decreasing cardiovascular mortality trends.

Blood Microbiota Profile Is Associated with the Responsiveness of Postprandial Lipemia to Platycodi radix Beverage: A Randomized Controlled Trial in Healthy Subjects

Prolonged postprandial hyperlipidemia may cause the development of cardiovascular diseases. This study explored whether postprandial triglyceride-rich lipoprotein (TRL) clearance responsiveness to Platycodi radix beverage (PR) is associated with changes in blood microbiota profiles. We conducted an 8-week randomized controlled clinical trial involving normolipidemic adults with low fruit and vegetable intakes. Participants underwent an oral fat tolerance test and 16S amplicon sequencing analysis of blood microbiota. Using the Qualitative Interaction Trees, we identified responders as those with higher baseline dietary fat intake (>38.5 g/day) and lipoprotein lipase levels (>150.6 ng/mL), who showed significant reductions in AUC for triglyceride (TG) and chylomicron-TG after the oral fat tolerance test. The LEfSe analysis showed differentially abundant blood microbiota between responders and non-responders. A penalized logistic regression algorithm was employed to predict the responsiveness to intervention on the TRL clearance based on the background characteristics, including the blood microbiome. Our findings suggest that PR intake can modulate postprandial TRL clearance in adults consuming higher fat intake over 38.5 g/day and low fruit and vegetable intake through shared links to systemic microbial signatures.

Validation of low-density lipoprotein cholesterol equations in pediatric population

Several studies have shown a high prevalence of dyslipidemia in children. Since childhood lipid concentrations continue into adulthood, recognition of lipid abnormalities in the early period is crucial to prevent the development of future coronary heart disease (CHD). Low density lipoprotein cholesterol (LDL-C) is one of the most used parameters in the initiation and follow-up of treatment in patients with dyslipidemia. It is a well known fact that LDL-C lowering therapy reduces the risk of future CHD. Therefore, accurate determination of the LDL-C levels is so important for the management of lipid abnormalities. This study aimed to validate different LDL-C estimating equations in the Turkish population, composed of children and adolescents. A total of 3,908 children below 18 years old at Sivas Cumhuriyet University Hospital (Sivas, Turkey) were included in this study. LDL-C was directly measured by direct homogeneous assays, i.e., Roche, Beckman, Siemens and estimated by Friedewald's, Martin/Hopkins', extended Martin-Hopkins' and Sampson's formulas. The concordances between the estimations obtained by the formulas and the direct measurements were evaluated both overall and separately for the LDL-C, triglycerides (TG) and non-high-density lipoprotein cholesterol (non-HDL-C) sublevels. Linear regression analysis was performed and residual error plots were generated between each estimation and direct measurement method. Coefficient of determination (R ²) and mean absolute deviations were also evaluated. The overall concordance of Friedewald, Sampson, Martin-Hopkins and the extended Martin-Hopkins formula were 64.6%, 69.9%, 69.4%, and 84.3% for the Roche direct assay, 69.8%, 71.6%, 73.6% and 80.4% for the Siemens direct assay, 66.5%, 68.8%, 68.9% and 82.1% for the Beckman direct assay, respectively. The extended Martin-Hopkins formula had the highest concordance coefficient in both overall and all sublevels of LDL-C, non-HDL-C, and TG. When estimating the LDL-C categories, the highest underestimation degrees were obtained with the Friedewald formula. Our analysis, conducted in a large pediatric population, showed that the extended Martin-Hopkins equation gives more reliable results in estimation of LDL-C compared to other equations.

Effects of Serum Lipids on the Long-Term Prognosis of Ampullary Adenocarcinoma Patients after Curative Pancreatoduodenectomy

BACKGROUND

Serum lipids (SLs), the prominent indicators of lipid metabolism, produce an intricate impact on proliferation, invasion, and metastasis of cancer cells. However, the effects of serum lipids on the prognosis of ampullary adenocarcinoma (AC) have not been investigated.

METHODS

Patients with AC in the National Cancer Center of China between January 1998 and December 2020 were retrospectively reviewed. Survival analysis for overall survival (OS, Time from operation to death) and recurrence-free survival (RFS, Time from operation to first-time recurrence) was performed using Kaplan-Meier analysis and Cox proportional hazards models.

RESULTS

A total of 232 AC patients were enrolled into the study. SLs levels were significantly lower in patients with vascular invasion compared to those without (all p < 0.05). The 1-year, 3-year, and 5-year OS rates for AC patients were 86.1%, 64.1%, and 47.6% and 75.8%, 54.8%, and 46.5% for RFS. Biliary/pancreatic fistula (31.9%) and chemotherapy (81.4%) were the majority of postoperative complications and adjuvant therapy, respectively. According to Cox analysis, preoperative LDL-C was an independent prognostic factor for RFS (HR = 0.43, 95% CI: 0.21-0.85, p = 0.015), whereas no statistical significance existed in the analysis of HDL-C, TC, and TG.

CONCLUSIONS

High levels of preoperative LDL-C is a significant predictor of prolonged prognosis in AC patients, which was also observed to be a protective factor to reduce vascular invasion.

Plasma oxysterols in drug-free patients with schizophrenia

Evidence from clinical, genetic, and medical studies has shown the neuronal developmental disorder aspect of schizophrenia (SZ). Whereas oxysterols are vital factors in neurodevelopment, it is still unknown whether they are involved in the pathophysiology of SZ. The current study aims to explore the profile of oxysterols in plasma, ratio to total cholesterol (Tchol) and the association with clinical factors in patients with SZ. Forty men diagnosed with SZ and forty healthy controls matched for age and sex were included in the study. The ratios of cholestane-3β,5α,6β-triol, 27-hydroxycholesterol (27-OHC) and Cholestanol to Tchol increased in the schizophrenic group compared to controls. However, levels of 24S-hydroxycholesterol (24-OHC) were not significantly different between patients and controls. For the SZ patients, the plasma 24-OHC levels were positively correlated with the positive and negative syndrome total scores (PANSS) but negatively correlated with the Montreal Cognitive Assessment scores (MOCA). Moreover, the ratio Cholestanol to Tchol was negatively correlated with MOCA scores and positively correlated with PANSS general. The binary logistic regression analysis revealed that the ratio Cholestane-3β,5α,6β-triol/TChol could be considered as an independent risk factor for SZ. On the other hand, the receiver's operating characteristics analysis corresponding to potential biomarkers on SZ showed Areas Under the Curve (AUCs) of 82.1%; 69.7% and 77.6% for the ratio of Cholestane-3β,5α,6β-triol/TChol, 27-OHC/TChol and Cholestanol/TChol respectively. The relevance of Cholestane-3β,5α,6β-triol, 27-OHC and Cholestanol assays as biomarkers of this disease deserves further investigation.

Possible mechanisms of cholesterol elevation aggravating COVID-19

Importance: Despite the availability of a vaccine against the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), humans will have to live with this virus and the after-effects of the coronavirus disease 2019 (COVID-19) infection for a long time. Cholesterol plays an important role in the infection and prognosis of SARS-CoV-2, and the study of its mechanism is of great significance not only for the treatment of COVID-19 but also for research on generic antiviral drugs. Observations: Cholesterol promotes the development of atherosclerosis by activating NLR family pyrin domain containing 3 (NLRP3), and the resulting inflammatory environment indirectly contributes to COVID-19 infection and subsequent deterioration. In in vitro studies, membrane cholesterol increased the number of viral entry sites on the host cell membrane and the number of angiotensin-converting enzyme 2 (ACE2) receptors in the membrane fusion site. Previous studies have shown that the fusion protein of the virus interacts with cholesterol, and the spike protein of SARS-CoV-2 also requires cholesterol to enter the host cells. Cholesterol in blood interacts with the spike protein to promote the entry of spike cells, wherein the scavenger receptor class B type 1 (SR-B1) plays an important role. Because of the cardiovascular protective effects of lipid-lowering therapy and the additional anti-inflammatory effects of lipid-lowering drugs, it is currently recommended to continue lipid-lowering therapy for patients with COVID-19, but the safety of extremely low LDL-C is questionable. Conclusions and Relevance: Cholesterol can indirectly increase the susceptibility of patients to SARS-CoV-2 and increase the risk of death from COVID-19, which are mediated by NLRP3 and atherosclerotic plaques, respectively. Cholesterol present in the host cell membrane, virus, and blood may also directly participate in the virus cell entry process, but the specific mechanism still needs further study. Patients with COVID-19 are recommended to continue lipid-lowering therapy.

Plasma oxysterols: Altered level of plasma 24-hydroxycholesterol in patients with bipolar disorder

Cholesterol and its oxygenated metabolites, including oxysterols, are intensively investigated as potential players in the pathophysiology of brain disorders. Altered oxysterol levels have been described in patients with numerous neuropsychiatric disorders. Recent studies have shown that Bipolar disorder (BD) is associated with the disruption of cholesterol metabolism. The present study was aimed at investigating the profile of oxysterols in plasma, their ratio to total cholesterol and their association with clinical parameters in patients with BD. Thirty three men diagnosed with BD and forty healthy controls matched for age and sex were included in the study. Oxysterol levels were measured by isotope-dilution ultra-performance liquid chromatography-tandem mass spectrometry. Significantly higher levels were observed for cholestane-3β,5α,6β-triol, 27-hydroxycholesterol (27-OHC) and Cholestanol in patients with BD. The concentration of 24-hydroxycholesterol (24-OHC) was significantly lower in patients compared to controls. 24-OHC was also negatively correlated to MAS subscale score (r =-0.343; p = 0.049). In patients, 24-OHC was inversely correlated with age (r = -0.240; p = 0.045). Multivariate analysis found that BD acute decompensation was independently related to the rise in plasma 24-OHC (p = 0.002; OR = 0.966, 95 % CI [0.945 - 0.987]). However, the 24-OHC assay relevance as a biomarker of this disease deserves further investigation in other studies.

Calculated values of serum LDL-cholesterol (LDL-C) - for better or worse?

BACKGROUND AND AIMS

The use of Friedewald's formula to calculate serum low-density lipoprotein cholesterol (LDL-C) is well-known to have limitations. A modification of it, in 2013, has been proposed to be superior. However, it was not known whether LDL-C values (calculated by the modified formula) meet laboratory performance criteria for their estimation. This study aimed to evaluate this.

METHODS AND RESULTS

LDL-C values were calculated for 129,821 lipid profiles, using both Friedewald's formula and its modified version. Kappa statistics and intra-class correlation coefficient (ICC) were used to determine degree of agreement between directly measured and calculated values for LDL-C. Bias and total percentage error of the values were calculated. LDL-C concentrations calculated by the modified formula showed a greater degree of agreement with directly measured values (kappa = 0.713) than those calculated by Friedewald's formula (kappa = 0.595). Both the formulae produced values with negative biases (-3.47 for the modified formula and -7.62 for Friedewald's formula) and total percentage errors above the recommended limit of 12% (15.57% for the modified formula and 21.77% for Friedewald's formula). ICC showed that values calculated by the modified formula showed a greater degree of agreement with directly measured values, across a range of LDL-C values.

CONCLUSION

Calculated LDL-C values, using the modified formula, showed better agreement with directly measured values, and less bias and percentage total error than those obtained by use of Friedewald's formula. However, the percentage total error with use of the modified formula exceeded the recommended limit for LDL-C.

Triglycerides, hypertension, and smoking predict cardiovascular disease in dysbetalipoproteinemia

BACKGROUND

Dysbetalipoproteinemia (DBL) is an autosomal recessive lipid disorder associated with a reduced clearance of remnant lipoproteins and is associated with an increased cardiovascular disease (CVD) risk. The genetic cause of DBL is apoE2 homozygosity in 90% of cases. However, a second metabolic hit must be present to precipitate the disease. However, no study has investigated the predictors of CVD, peripheral artery disease and coronary artery disease in a large cohort of patients with DBL.

OBJECTIVE

The objectives of this study were to describe the clinical characteristics of a DBL cohort and to identify the predictors of CVD, peripheral artery disease, and coronary artery disease in this population.

METHODS

The inclusion criteria included age ≥ 18 years, apoE2/E2, triglycerides (TG) > 135 mg/dL and VLDL-C/plasma TG ratio > 0.30.

RESULTS

We studied 221 adult DBL patients, of which 51 (23%) had a history of CVD. We identified 3 independent predictors of CVD, namely hypertension (OR 5.68, 95% CI 2.13-15.16, P = .001), pack year of smoking (OR 1.03, 95% CI 1.01-1.05, P = .01) and TG tertile (OR 1.82, 95% CI 1.09-3.05, P = .02). The CVD prevalence was 51% in patients with hypertension and 18% in those without hypertension (P = .00001), and 30% in the highest TG tertile vs 15% in the lowest tertile (P = .04). Similarly, the CVD prevalence was higher in heavy smokers compared with nonsmokers (36% vs 13%, P = .006).

CONCLUSION

Hypertension, smoking, and TG are independently associated with CVD risk in patients with DBL. Aggressive treatment should be initiated in patients with DBL because of the increased risk of CVD.

Practical guide for the use of PCSK9 inhibitors in Portugal

Reducing low-density lipoprotein cholesterol (LDL-C) levels is one of the most important strategies for reducing the risk of cardiovascular events. However, in clinical practice, a high proportion of patients do not achieve recommended LDL-C levels through lifestyle and lipid-lowering therapy with statins and ezetimibe. PCSK9 inhibitors (PCSK9i) are a new therapeutic option that significantly (50-60%) reduces LDL-C levels, which in clinical trials translates into an additional reduction in risk for cardiovascular events, and has a good safety profile. However, it is a high-cost therapy, and therefore its use in clinical practice should take its cost-effectiveness into account. Priority should be given to use in patients at higher cardiovascular risk and those in whom high LDL-C levels persist despite optimal lipid-lowering therapy. This consensus document aims to summarize the main data on the clinical use of PCSK9i and to make recommendations for Portugal on the profile of patients who may benefit most from this therapy.

Prevalence of dyslipidemia and prediction of 10-year CVD risk among older adults living in southeast coastal regions in China: a cross-sectional study

Objective: This study aims to analyze the prevalence of dyslipidemia and identify the cardiovascular disease (CVD) risk stratification among older adults living in Quanzhou, China’s southeast coastal region, where the ancient Maritime Silk Road starts.

Methods: A population-based cross-sectional survey of 2,018 adults was conducted in 60–98-year-old residents in Quanzhou from September 2016 to March 2018 using multistage stratified cluster random sampling. The 10-year CVD risk was also estimated by applying the Chinese model recommended by the Chinese Guidelines for Prevention of Cardiovascular Diseases.

Results: The overall prevalence of dyslipidemia among older adults was 56.8%. The prevalence of high total cholesterol (TC), high low-density lipoprotein cholesterol (LDL-C), low high-density lipoprotein cholesterol (HDL-C) and high triglyceride (TG) were 8.4%, 13.9%, 23.1% and 11.4%, respectively. The mean levels of TC, LDL-C, HDL-C and TG were 5.12±1.18, 3.37±0.81, 1.03±0.27 and 1.65±0.76 mmol/L, respectively. Older adults had low risk, moderate risk and high risk for CVD, which were 49.7%, 36.8% and 13.5%, respectively. Age, body mass index and abdominal obesity were significantly associated with the risk of increasing LDL-C levels and were positively correlated to CVD risk.

Conclusion: The prevalence of high TC, high LDL-C, low HDL-C and high TG was relatively low among older adults in Quanzhou, but their lipid levels were high. Approximately half of the elderly adults had moderate or high CVD risk. The personalized primary prevention and control of CVD are recommended for elderly people to identify high-risk individuals.

Antisense molecules: A new class of drugs

An improved understanding of disease pathogenesis leads to identification of novel therapeutic targets. From a pharmacologic point of view, these can be addressed by small chemical compounds, so-called biologicals (eg, mAbs and recombinant proteins), or by a rather new class of molecule based on the antisense concept. Recently, a new wave of clinical studies exploring antisense strategies is evolving. In addition to cancer, they include predominantly trials on infectious and noninfectious diseases, such as chronic inflammatory and metabolic conditions. This article, based on a systematic PubMed literature search, highlights recent developments in this emerging field.

Claimed effects, outcome variables and methods of measurement for health claims proposed under European Community Regulation 1924/2006 in the framework of protection against oxidative damage and cardiovascular health

BACKGROUND AND AIMS

The high number of negative opinions from the European Food Safety Authority (EFSA) to the requests for authorization of health claims is largely due to the design of human intervention studies, including the inappropriate choice of outcome variables (OVs) and of their methods of measurement (MMs). The present manuscript reports the results of an investigation aimed to collect, collate and critically analyse the information in relation to claimed effects, OVs and MMs, in the context of protection against oxidative damage and cardiovascular health compliant with Regulation 1924/2006.

METHODS AND RESULTS

Claimed effects, OVs and the related MMs were collected from EFSA Guidance documents and applications for authorization of health claims under Articles 13.5 and 14. The OVs and their MMs were evaluated only if the claimed effect was sufficiently defined and was considered beneficial by EFSA. The collection, collation and critical analysis of the relevant scientific literature consisted in the definition of the keywords, the PubMed search strategies and the creation of databases of references. The critical analysis of the OVs and their MMs was performed on the basis of the literature review and was aimed at defining the appropriateness of OVs and MMs in the context of the specific claimed effects.

CONCLUSIONS

The information provided in this document could serve to EFSA for the development of further guidance on the scientific requirements for health claims, as well as to the stakeholders for the proper design of human intervention studies aimed to substantiate such health claims.

PCSK9 inhibitors in the current management of atherosclerosis

The history of proprotein convertase subtilisin/kexin type 9 (PCSK9) in medical science is fascinating and the evolution of knowledge of its function has resulted in new medications of major importance for the cardiovascular (CV) patient. PCSK9 functions as a negative control or feedback for the cell surface receptors for low-density lipoprotein including its component of cholesterol (LDL-C). The initial and key findings were that different abnormalities of PCSK9 can result in an increase or a decrease of LDL-C because of more or less suppression of cell surface receptors. These observations gave hints and awoke interest that it might be possible to prepare monoclonal antibodies to PCSK9 and decrease its activity, after which there should be more active LDL-C cell receptors. The rest is a fascinating story that currently has resulted in two PCSK9 inhibitors, alirocumab and evolocumab, which, on average, decrease LDL-C approximately 50%. Nevertheless, if there are no contraindications, statins remain the standard of prevention for the high-risk CV patient and this includes both secondary and primary prevention. The new inhibitors are for the patient that does not attain the desired target for LDL-C reduction while taking a maximum statin dose or who does not tolerate any statin dose whatsoever. Atherosclerosis can be considered a metabolic disease and the clinician needs to realize this and think more and more of CV prevention. These inhibitors can contribute to both the stabilization and regression of atherosclerotic plaques and thereby avoid or delay major adverse cardiac events. (United States).

Can wheat germ have a beneficial effect on human health? A study protocol for a randomised crossover controlled trial to evaluate its health effects

INTRODUCTION

Cardiovascular diseases (CVD) are the leading cause of mortality worldwide and diet is an important contributor to CVD risk. Thus, several food derivatives are being investigated for their beneficial impact on reducing cardiometabolic risk factors, either in risk groups or in healthy population as a preventive measure. Wheat germ is a food by-product with high nutritional value, especially as a concentrated source of dietary fibre and essential fatty acids, but its incorporation into the diet has been rare up to now. Previous studies do not clarify the hypothesised potential causal relationship between the consumption of wheat germ and benefits for human health.

METHODS AND ANALYSIS

We are conducting a randomised, double-blinded, crossover, placebo-controlled clinical trial designed to assess the physiological effects of daily consumption of wheat germ-enriched bread (containing 6 g of wheat germ) compared with non-enriched bread, over a 4-week period with a 15-week follow-up, in a healthy human population. A total of 55 participants (healthy volunteers, aged 18-60) have been recruited from the Porto metropolitan area in northern Portugal. Our aim is to evaluate the health effects of wheat germ on blood cholesterol and triglycerides, postprandial glycaemic response, gastrointestinal function and discomfort, and changes in intestinal microbiota and insulin resistance as secondary outcomes. The study follows the best practices for evaluating health claims in food according to the European Food Safety Authority (EFSA) scientific opinion, namely random allocation, double blinding, reporting methods to measure and maximise compliance, and validated outcomes with beneficial physiological effects as recommended by EFSA.

ETHICS AND DISSEMINATION

The study has been approved by the Health Ethics Committee of São João Hospital Centre (156-15) and the Ethics Committee of Faculty of Medicine of the University of Porto (PCEDCSS-FMUP07/2015). Results will be disseminated through peer-reviewed publications and presentations at international scientific meetings.

TRIAL REGISTRATION NUMBER

NCT02405507; pre-results.

Recent advances in the pharmacological management of hypercholesterolaemia

The recent developments in pharmacological interventions that reduce LDL cholesterol have been remarkable, coming more than a decade after the approval of the last LDL-cholesterol-lowering drug, the cholesterol absorption inhibitor ezetimibe. Within just a few years, four new LDL-cholesterol-lowering agents have received regulatory approval. Lomitapide and mipomersen inhibit the production of LDL, but also increase hepatic fat and are licensed specifically for homozygous familial hypercholesterolaemia. Alirocumab and evolocumab are monoclonal antibodies that bind to proprotein convertase subtilisin/kexin type 9 (PCSK9), lowering LDL by about 50-60%. These drugs are approved for use in patients with cardiovascular disease or familial hypercholesterolaemia whose LDL cholesterol levels are insufficiently controlled on standard agents. Although definitive clinical efficacy and long-term safety data are still needed, antibody-based PCSK9 inhibitors promise to meet much of the unmet medical need in the treatment of raised LDL cholesterol. However, several additional approaches to inhibiting PCSK9, as well as other classes of LDL-lowering therapies, are in clinical development. Here we summarise the science behind the development of the newly approved LDL-cholesterol-lowering drugs and critically review their efficacy and safety data, highlighting unanswered research questions. Finally, we discuss emerging LDL-lowering therapies in clinical development.

Current Treatment of Dyslipidemia: A New Paradigm for Statin Drug Use and the Need for Additional Therapies

Coronary heart disease (CHD) is the leading cause of death in most countries, with the high prevalence currently driven by dual epidemics of obesity and diabetes. Statin drugs, the most effective, evidence-based agents to prevent and treat this disease, have a central role in management and are advised in all published guidelines. The 2013 American College of Cardiology/American Heart Association (ACC/AHA) cholesterol and assessment guidelines ('new ACC/AHA guidelines') emphasized global cardiovascular (CV) risk reduction as opposed to targeting low-density lipoprotein-cholesterol (LDL-C) levels, stressed the use of statins in two dose intensities, utilized a new risk calculator using pooled cohort equations, and lowered the risk cutoff for initiation of statin therapy. Although there were major strengths of the new ACC/AHA guidelines, substantial controversy followed their release, particulars of which are discussed in this review. They were generally regarded as improvements in an ongoing transition using evidenced-based data for maximum patient benefit. Several guidelines, other than the ACC/AHA guidelines, currently provide practitioners with choices, some depending on practice locations. Cholesterol control with statin drugs is used in all paradigms. However, some patients respond inadequately, approximately 15% are intolerant, and other factors prevent attaining cholesterol goals in as many as 40% of patients. Even after treatment, substantial residual risk for ongoing major events remains. Another readily available modality that can rival statin drugs in effectiveness is vast improvement in diet and lifestyle within the general population; however, despite great effort, existing programs to implement such changes have failed. Hence, despite unrivaled success, there is great need for additional drugs to prevent and treat CHD, whether as monotherapy or in combination with statin drugs. New American guidelines do not discuss or recommend any nonstatin drugs for CHD, and the US FDA has moved away from approving drugs based solely on changes in surrogates in the absence of clinical outcomes trials. Both have significantly altered the realities of developing pharmacotherapies and cardiology practice.

Defining the Role of PCSK9 Inhibitors in the Treatment of Hyperlipidemia

Statins remain the mainstay of medical cardiovascular risk reduction because of their effectiveness in decreasing low-density lipoprotein cholesterol (LDL-C) as well as some other potentially beneficial effects. The latest US 2013 lipid guidelines essentially recommend only the prescription of a high-dose statin for the high-risk patient. However, both quite old and quite new outcomes evidence, such as reported for ezetimibe, emphasize that LDL-C lowering is, in and of itself, quite important for cardiovascular risk reduction. It appears that the proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors represent a major new contribution to this effort, especially for patients with severe familial hypercholesterolemia, proven clinical cardiovascular disease, statin intolerance, or failure to attain an acceptably low LDL-C goal despite maximum available medical management. Very recent clinical trials have proven overwhelmingly the effectiveness and safety of PCSK9 inhibitors for lowering LDL-C. Both alirocumab and evolocumab have now been approved by the US FDA and there are some initial favorable outcomes data. This review is intended to summarize available evidence and emphasize the possible clinical role of these inhibitors following the approval of alirocumab and evolocumab. Understanding the negative receptor feedback of PCSK9 and the mechanism and beneficial effect of PCSK9 inhibitors for cardiovascular risk reduction is essential for the up-to-date practitioner of cardiovascular medicine. There is every reasonable hope for significant cardiovascular benefit from these new additions to our medical cardiovascular armamentarium.

Association of the variants and haplotypes in the DOCK7, PCSK9 and GALNT2 genes and the risk of hyperlipidaemia

Little is known about the association between the single nucleotide polymorphisms (SNPs) and haplotypes of the dedicator of cytokinesis 7 (DOCK7), pro-protein convertase subtilisin/kexin type 9 (PCSK9) and polypeptide N-acetylgalactosaminyltransferase 2 (GALNT2) and serum lipid traits in the Chinese populations. This study was to determine the association between nine SNPs in the three genes and their haplotypes and hypercholesterolaemia (HCH)/hypertriglyceridaemia (HTG), and to identify the possible gene-gene interactions among these SNPs. Genotyping was performed in 733 HCH and 540 HTG participants. The haplotype of C-C-G-C-T-G-C-C-G [in the order of DOCK7 rs1168013 (G>C), rs10889332 (C>T); PCSK9 rs615563 (G>A), rs7552841 (C>T), rs11206517 (T>G); and GALNT2 rs1997947 (G>A), rs2760537 (C>T), rs4846913 (C>A) and rs11122316 (G>A) SNPs] was associated with increased risk of HCH and HTG. The haplotypes of C-C-G-C-T-G-C-C-A and G-C-G-T-T-G-T-C-G were associated with a reduced risk of HCH and HTG. The haplotypes of G-C-G-C-T-G-C-C-A and G-C-G-C-T-G-T-C-G were associated with increased risk of HCH. The haplotypes of C-T-G-C-T-G-C-C-G, G-C-A-C-T-G-C-C-G and G-C-G-C-T-G-C-C-A were associated with an increased risk of HTG. The haplotypes of G-C-G-C-T-G-T-C-A and G-C-G-T-T-G-T-C-G were associated with a reduced risk of HTG. In addition, possible inter-locus interactions among the DOCK7, PCSK9 and GALNT2 SNPs were also noted. However, further functional studies of these genes are still required to clarify which SNPs are functional and how these genes actually affect the serum lipid levels.

Effect of Low-Density Lipoprotein Cholesterol Lowering by Ezetimibe/Simvastatin on Outcome Incidence: Overview, Meta-Analyses, and Meta-Regression Analyses of Randomized Trials

This analysis investigated the extent of different outcome reductions from low-density lipoprotein cholesterol (LDL-C) lowering following ezetimibe/simvastatin treatment and the proportionality of outcome to LDL-C reductions. The authors searched PubMed between 1997 and mid-June 2015 (any language) and the Cochrane Library to identify all randomized controlled trials comparing ezetimibe/simvastatin with placebo or less intensive LDL-C lowering. Risk ratios (RR) and 95% confidence intervals (CIs), standardized to 20 mg/dL LDL-C reduction, were calculated for 5 primary outcomes (fatal and nonfatal) and 4 secondary outcomes (non-cardiovascular [CV] death, cancer, myopathy, and hepatopathy). Five ezetimibe/simvastatin RCTs (30 051 individuals) were eligible, 2 comparing ezetimibe/simvastatin vs placebo and 3 vs less intensive treatment. Outcomes reduced almost to the same extent were stroke (RR: -13%, 95% CI: -21% to -3%), coronary heart disease (CHD; RR: -12%, 95% CI: -19% to -5%), and composite of stroke and CHD (RR: -14%, 95% CI: -20% to -8%). Absolute risk reductions: 5 strokes, 10 CHD events, and 16 stroke and CHD events prevented for every 1000 patients treated for 5 years. Residual risk was almost 7× higher than absolute risk reduction for all the above outcomes. All death outcomes were not reduced, and secondary outcomes did not differ between groups. Logarithmic risk ratios were not associated with LDL-C lowering. Our meta-analysis provides evidence that, in patients with different CV disease burden, major CV events are safely reduced by LDL-C lowering with ezetimibe/simvastatin, while raising the hypothesis that the extent of LDL-C lowering might not be accompanied by incremental clinical-event reduction.

Hypercholesterolemia, low density lipoprotein receptor and proprotein convertase subtilisin/kexin-type 9

Atherosclerotic cardiovascular disease is the main cause of mortality and morbidity in the world. Plasma levels of low density lipoprotein cholesterol (LDL-C) are positively correlated with the risk of atherosclerosis. High plasma LDL concentrations in patients with hypercholesterolemia lead to build-up of LDL in the inner walls of the arteries, which becomes oxidized and promotes the formation of foam cells, consequently initiating atherosclerosis. Plasma LDL is mainly cleared through the LDL receptor (LDLR) pathway. Mutations in the LDLR cause familiar hypercholesterolemia and increase the risk of premature coronary heart disease. The expression of LDLR is regulated at the transcriptional level via the sterol regulatory element binding protein 2 (SREBP-2) and at the posttranslational levels mainly through proprotein convertase subtilisin/kexin-type 9 (PCSK9) and inducible degrader of the LDLR (IDOL). In this review, we summarize the latest advances in the studies of PCSK9.

Validation of the pooled cohort risk score in an Asian population - a retrospective cohort study

BACKGROUND

The Pooled Cohort Risk Equation was introduced by the American College of Cardiology (ACC) and American Heart Association (AHA) 2013 in their Blood Cholesterol Guideline to estimate the 10-year atherosclerotic cardiovascular disease (ASCVD) risk. However, absence of Asian ethnicity in the contemporary cohorts and limited studies to examine the use of the risk score limit the applicability of the equation in an Asian population. This study examines the validity of the pooled cohort risk score in a primary care setting and compares the cardiovascular risk using both the pooled cohort risk score and the Framingham General Cardiovascular Disease (CVD) risk score.

METHODS

This is a 10-year retrospective cohort study of randomly selected patients aged 40-79 years. Baseline demographic data, co-morbidities and cardiovascular (CV) risk parameters were captured from patient records in 1998. Pooled cohort risk score and Framingham General CVD risk score for each patient were computed. All ASCVD events (nonfatal myocardial infarction, coronary heart disease (CHD) death, fatal and nonfatal stroke) occurring from 1998-2007 were recorded.

RESULTS

A total of 922 patients were studied. In 1998, mean age was 57.5 ± 8.8 years with 66.7% female. There were 47% diabetic patients and 59.9% patients receiving anti-hypertensive treatment. More than 98% of patients with pooled cohort risk score ≥7.5% had FRS >10%. A total of 45 CVD events occurred, 22 (7.2%) in males and 23 (3.7%) in females. The median pooled cohort risk score for the population was 10.1 (IQR 4.7-20.6) while the actual ASCVD events that occurred was 4.9% (45/922). Our study showed moderate discrimination with AUC of 0.63. There was good calibration with Hosmer-Lemeshow test χ2 = 12.6, P = 0.12.

CONCLUSIONS

The pooled cohort risk score appears to overestimate CV risk but this apparent over-prediction could be a result of treatment. In the absence of a validated score in an untreated population, the pooled cohort risk score appears to be appropriate for use in a primary care setting.