Underappreciated opportunities for low-density lipoprotein management in patients with cardiometabolic residual risk

Low-density lipoprotein particles in atherosclerosis

Among the diseases causing human death, cardiovascular disease (CVD) remains number one according to the World Health Organization report in 2021. It is known that atherosclerosis is the pathological basis of CVD. Low-density lipoprotein (LDL) plays a pivotal role in the initiation and progression of atherosclerotic CVD (ASCVD). LDL cholesterol (LDL-C) is the traditional biological marker of LDL. However, large numbers of patients who have achieved the recommended LDL-C goals still have ASCVD risk. In multiple prospective studies, LDL particle (LDL-P) is reported to be more accurate in predicting CVD risk than LDL-C. LDL-Ps differ in size, density and chemical composition. Numerous clinical studies have proved that the atherogenic mechanisms of LDL-Ps are determined not only by LDL number and size but also by LDL modifications. Of note, small dense LDL (sdLDL) particles possess stronger atherogenic ability compared with large and intermediate LDL subfractions. Besides, oxidized LDL (ox-LDL) is another risk factor in atherosclerosis. Among the traditional lipid-lowering drugs, statins induce dramatic reductions in LDL-C and LDL-P to a lesser extend. Recently, proprotein convertase subtilsin/kexin type 9 inhibitors (PCSK9i) have been demonstrated to be effective in lowering the levels of LDL-C, LDL-P, as well as CVD events. In this article, we will make a short review of LDL metabolism, discuss the discordance between LDL-C and LDL-P, outline the atherogenic mechanisms of action of LDL by focusing on sdLDL and ox-LDL, summarize the methods used for measurement of LDL subclasses, and conclude the advances in LDL-lowering therapies using statins and PCSK9i.

Role of Resveratrol in Prevention and Control of Cardiovascular Disorders and Cardiovascular Complications Related to COVID-19 Disease: Mode of Action and Approaches Explored to Increase Its Bioavailability

Resveratrol is a phytoalexin produced by many plants as a defense mechanism against stress-inducing conditions. The richest dietary sources of resveratrol are berries and grapes, their juices and wines. Good bioavailability of resveratrol is not reflected in its high biological activity in vivo because of resveratrol isomerization and its poor solubility in aqueous solutions. Proteins, cyclodextrins and nanomaterials have been explored as innovative delivery vehicles for resveratrol to overcome this limitation. Numerous in vitro and in vivo studies demonstrated beneficial effects of resveratrol in cardiovascular diseases (CVD). Main beneficial effects of resveratrol intake are cardioprotective, anti-hypertensive, vasodilatory, anti-diabetic, and improvement of lipid status. As resveratrol can alleviate the numerous factors associated with CVD, it has potential as a functional supplement to reduce COVID-19 illness severity in patients displaying poor prognosis due to cardio-vascular complications. Resveratrol was shown to mitigate the major pathways involved in the pathogenesis of SARS-CoV-2 including regulation of the renin-angiotensin system and expression of angiotensin-converting enzyme 2, stimulation of immune system and downregulation of pro-inflammatory cytokine release. Therefore, several studies already have anticipated potential implementation of resveratrol in COVID-19 treatment. Regular intake of a resveratrol rich diet, or resveratrol-based complementary medicaments, may contribute to a healthier cardio-vascular system, prevention and control of CVD, including COVID-19 disease related complications of CVD.

Physicochemical Properties of Lipoproteins Assessed by Nuclear Magnetic Resonance as a Predictor of Premature Cardiovascular Disease. PRESARV-SEA Study

Some lipoprotein disorders related to the residual risk of premature cardiovascular disease (PCVD) are not detected by the conventional lipid profile. In this case-control study, the predictive power of PCVD of serum sdLDL-C, measured using a lipoprotein precipitation method, and of the physicochemical properties of serum lipoproteins, analyzed by nuclear magnetic resonance (NMR) techniques, were evaluated. We studied a group of patients with a first PCVD event (n = 125) and a group of control subjects (n = 190). Conventional lipid profile, the size and number of Very Low Density Lipoproteins (VLDL), Low Density Lipoproteins (LDL), High Density Lipoproteins (HDL) particles, and the number of particles of their subclasses (large, medium, and small) were measured. Compared to controls, PCVD patients had lower concentrations of all LDL particles, and smaller and larger diameter of LDL and HDL particles, respectively. PCVD patients also showed higher concentrations of small dense LDL-cholesterol (sdLDL), and triglycerides (Tg) in LDL and HDL particles (HDL-Tg), and higher concentrations of large VLDL particles. Multivariate logistic regression showed that sdLDL-C, HDL-Tg, and large concentrations of LDL particles were the most powerful predictors of PCVD. A strong relationship was observed between increased HDL-Tg concentrations and PCVD. This study demonstrates that beyond the conventional lipid profile, PCVD patients have other atherogenic lipoprotein alterations that are detected by magnetic resonance imaging (MRI) analysis.

Serum apolipoprotein B is associated with increased risk of metabolic syndrome among middle-aged and elderly Chinese: A cross-sectional and prospective cohort study

BACKGROUND

Serum apolipoprotein (apo) B has been associated with an increased risk of atherosclerotic cardiovascular diseases. However, findings on the association between apoB and the risk of metabolic syndrome (MetS) are inconsistent. The purpose of this study was to investigate the association between serum apoB and MetS risk in Chinese population.

METHODS

A baseline survey was conducted in a population-based cohort of 10 340 adults aged ≥40 years in Shanghai, China, in 2010. A follow-up visit was conducted to assess incident diabetes in 2015.

RESULTS

At baseline, 2794 of 10 340 participants (27.02%) had MetS. Serum apoB was significantly associated with an increased risk of prevalent MetS. Multivariable-adjusted odds ratios and 95% confidence intervals (CIs) for quintiles 2-5 compared with quintile 1 (reference) were 1.29 (1.02-1.63), 1.47 (1.18-1.84), 1.32 (1.06-1.65), and 2.02 (1.61-2.51), respectively (P_trend  < 0.05). During an average of 5.1 years follow-up, 4627 individuals without MetS at baseline showed a significant association between apoB and the risk of incident MetS. Multivariable-adjusted risk ratios (95% CIs) for subjects in apoB quintiles 2-5 compared with the reference were 1.43 (1.13-1.82), 1.57 (1.25-1.98), 1.74 (1.38-2.18), and 2.07 (1.66-2.58), respectively (P_trend  < 0.05). Stratified analysis suggested that the above association was much stronger among normal weight individuals than in those who were overweight or obese.

CONCLUSION

These cross-sectional and prospective studies provide evidence that serum apoB is associated with existing MetS and is a possible predictor of the risk of MetS, especially among normal weight individuals.

Lipid findings from the Diabetes Education to Lower Insulin, Sugars, and Hunger (DELISH) Study

Background

A carbohydrate-restricted (CR) diet can improve glycemic control in people with type 2 diabetes mellitus (T2DM). There are concerns, however, that the high dietary fat content of CR diets can increase low-density lipoprotein cholesterol (LDL-C), thus increasing cardiovascular disease (CVD) risk. Quantifying CVD risk associated with changes in LDL-C in the context of CR diets is complicated by the fact that LDL-C reflects heterogeneous lipids. For example, small LDL particle number (sLDL-P) is more closely associated with CVD risk than is total LDL-C, and CR diets tend to decrease the proportion of sLDL-C in LDL-C, which standard lipid measures do not indicate. Advanced lipoprotein assays, such as nuclear magnetic resonance (NMR) testing, can subfractionate lipoproteins by size and density and may better depict the effects of CR diets on CVD risk.

Methods

Adults (N = 58) with T2DM (n = 37 women; baseline HbA1c ≥ 6.5%) completed a 6-month group-based CR diet intervention. We obtained a standard lipid panel, advanced lipoprotein assays (NMR testing), and two 24-h diet recalls at baseline and post-intervention (6 months). Participants also completed home-based blood ketone testing (a biological index of dietary adherence) during the final five weeks of the intervention.

Results

From baseline to post-intervention, participants had increased mean HDL-C, decreased triglycerides and triglyceride/HDL ratio, decreased mean sLDL-P, and increased LDL size, which reflect reductions in CVD risk (ps < 0.05). Participants did not have statistically significant changes in total cholesterol, non-HDL-C cholesterol, LDL-P, or HDL-P. Twelve participants (23.1%) had a ≥ 5% increase in sLDL-P. Exploratory analyses revealed that participants with sLDL-P increases of ≥ 5% reported larger increases in servings of red meat than participants without sLDL-P increases of ≥ 5% (+ 0.69 vs − 0.29 servings; p = 0.033). Changes in saturated fat intake were not associated with changes in sLDL-P.

Conclusions

Among most participants, we observed changes in several lipid measures consistent with decreased CVD risk. Approximately one in four participants evidenced increases in sLDL-P. Further research should clarify whether individuals with increased sLDL-P after implementing a CR diet can reverse observed increases by limiting red meat consumption.

Trial registration

ClinicalTrials.gov, NCT03207711, Registered 6/11/2017. Retrospectively registered.

The Effects of Resveratrol in Patients with Cardiovascular Disease and Heart Failure: A Narrative Review

Cardiovascular disease (CVD) is the main cause of death globally and responsible for the second highest number of deaths in Canada. Medical advancements in the treatment of CVD have led to patients living longer with CVD but often progressing to another condition called heart failure (HF). As a result, HF has emerged in the last decade as a major medical concern. Fortunately, various “traditional” pharmacotherapies for HF exist and have shown success in reducing HF-associated mortality. However, to augment the treatment of patients with CVD and/or HF, alternative pharmacotherapies using nutraceuticals have also shown promise in the prevention and treatment of these two conditions. One of these natural compounds considered to potentially help treat HF and CVD and prevent their development is resveratrol. Herein, we review the clinical findings of resveratrol’s ability to be used as an effective treatment to potentially help treat HF and CVD. This will allow us to gain a more fulsome appreciation for the effects of resveratrol in the health outcomes of specific patient populations who have various disorders that constitute CVD.

Characterization of Lipoprotein Composition and Function in Pediatric Psoriasis Reveals a More Atherogenic Profile

Psoriasis is associated with increased cardiovascular disease in adults, but the risk profile of children with psoriasis remains to be fully characterized. We measured lipoprotein composition and function in 44 patients with pediatric psoriasis and 44 age- and sex-matched healthy controls, using nuclear magnetic resonance spectroscopy and a validated ex vivo assay of high-density lipoprotein cholesterol efflux capacity. The mean age of the patients was 13 years and the population was ethnically diverse. Children with psoriasis had higher waist-to-hip ratios (0.85 vs. 0.80; P < 0.002) and insulin resistance measures (log-transformed homeostasis model assessment of insulin resistance 0.65 vs. 0.41; P = 0.07). Despite comparable traditional lipid values, having psoriasis was associated with higher apolipoprotein B concentrations (72.4 vs. 64.6; P = 0.02), decreased large high-density lipoprotein particles (5.3 vs. 6.7; P < 0.01), and reduced cholesterol efflux capacity after adjusting for age, sex, fasting glucose, homeostasis model assessment of insulin resistance, systolic blood pressure, body mass index, apolipoprotein A-1, and high-density lipoprotein cholesterol concentration (β -0.22; P = 0.02). Patients with pediatric psoriasis have a more atherogenic cardiometabolic risk profile, with evidence of insulin resistance and lipoprotein dysfunction by particle size, number, and functional assessment. These findings may provide a basis for the observed link later in life between psoriasis and cardiovascular disease, and support the need to screen and educate young patients to minimize later complications.

Effect of colesevelam HCl monotherapy on lipid particles in type 2 diabetes mellitus

Purpose

In addition to lowering hemoglobin A1C, colesevelam has been shown to improve the atherogenic lipoprotein profile of subjects with type 2 diabetes mellitus (T2DM) when used in combination with metformin and/or sulfonylureas. A recent study evaluated the effects of colesevelam as antidiabetes monotherapy in adults with T2DM who had inadequate glycemic control (hemoglobin A1C ≥7.5 to ≤9.5 %) with diet and exercise alone; we report here the effects on lipoprotein particle subclasses.

Methods

Subjects were randomized to receive oral colesevelam 3.75 g/day (n = 176) or placebo (n = 181) for 24 weeks. Changes in lipoprotein particle subclasses were determined by nuclear magnetic resonance spectroscopy.

Results

At Week 24 with last observation carried forward, colesevelam produced a reduction in total low-density lipoprotein (LDL) particle concentration (baseline: 1,611 nmol/L; least-squares [LS] mean treatment difference: −143 nmol/L, p < 0.0001) versus placebo; reductions were also seen in large, small, and very small LDL particle concentrations (all p < 0.05). There was also a reduction in total very low-density lipoprotein (VLDL) and chylomicron particle concentration (baseline: 88 nmol/L; LS mean treatment difference: −1 nmol/L, p = 0.82) that resulted from a lowering in small VLDL particle concentration (baseline: 45 nmol/L; LS mean treatment difference: −5 nmol/L, p = 0.03). In addition, with colesevelam there was an increase in total high-density lipoprotein (HDL) particle concentration versus placebo (baseline: 31 μmol/L; LS mean treatment difference: +0.6 μmol/L, p = 0.20), due to increases in the large (baseline: 5 μmol/L; LS mean treatment difference: +0.5 μmol/L, p = 0.007) and medium (baseline: 3 μmol/L; LS mean treatment difference: +0.8 μmol/L, p = 0.02) HDL subclasses.

Conclusions

Colesevelam monotherapy in subjects with T2DM resulted in generally favorable changes in certain lipoprotein subclass profiles compared with placebo.

Genetics and causality of triglyceride-rich lipoproteins in atherosclerotic cardiovascular disease

Triglycerides represent 1 component of a heterogeneous pool of triglyceride-rich lipoproteins (TGRLs). The reliance on triglycerides or TGRLs as cardiovascular disease (CVD) risk biomarkers prompted investigations into therapies that lower plasma triglycerides as a means to reduce CVD events. Genetic studies identified TGRL components and pathways involved in their synthesis and metabolism. We advocate that only a subset of genetic mechanisms regulating TGRLs contribute to the risk of CVD events. This "omic" approach recently resulted in new targets for reducing CVD events.

NMR measurement of LDL particle number using the Vantera Clinical Analyzer

BACKGROUND

The Vantera Clinical Analyzer was developed to enable fully-automated, high-throughput nuclear magnetic resonance (NMR) spectroscopy measurements in a clinical laboratory setting. NMR-measured low-density lipoprotein particle number (LDL-P) has been shown to be more strongly associated with cardiovascular disease outcomes than LDL cholesterol (LDL-C) in individuals for whom these alternate measures of LDL are discordant.

OBJECTIVE

The aim of this study was to assess the analytical performance of the LDL-P assay on the Vantera Clinical Analyzer as per Clinical Laboratory Standards Institute (CLSI) guidelines.

RESULTS

Sensitivity and linearity were established within the range of 300-3500 nmol/L. For serum pools containing low, medium and high levels of LDL-P, the inter-assay, intra-assay precision and repeatability gave coefficients of variation (CVs) between 2.6 and 5.8%. The reference interval was determined to be 457-2282 nmol/L and the assay was compatible with multiple specimen collection tubes. Of 30 substances tested, only 2 exhibited the potential for assay interference. Moreover, the LDL-P results from samples run on two NMR platforms, Vantera Clinical Analyzer and NMR Profiler, showed excellent correlation (R(2)=0.96).

CONCLUSIONS

The performance characteristics suggest that the LDL-P assay is suitable for routine testing in the clinical laboratory on the Vantera Clinical Analyzer, the first automated NMR platform that supports NMR-based clinical assays.

Cardiovascular risk in patients achieving low-density lipoprotein cholesterol and particle targets

OBJECTIVES

Previous research suggests that LDL particle number (LDL-P) may be a better tool than LDL cholesterol (LDL-C) to guide LDL-lowering therapy. Using real-world data, this study has two objectives: [1] to determine the incidence of CHD across LDL-P thresholds; and [2] to compare CHD/stroke events among patients achieving comparably low LDL-P or LDL-C levels.

METHODS

A claims analysis was conducted among high-risk patients identified from the HealthCore Integrated Research Database(SM). The impact of LDL levels on risk was compared across cohorts who achieved LDL-P <1000 nmol/L or LDL-C <100 mg/dL. Cohorts were matched to balance demographic and comorbidity differences.

RESULTS

Among 15,569 patients with LDL-P measurements, the risk of a CHD event increased by 4% for each 100 nmol/L increase in LDL-P level (HR 1.04; 95% CI 1.02-1.05, p < .0001). The comparative analysis included 2,094 matched patients with ≥12 months of follow-up, 1,242 with ≥24 months and 705 with ≥36 months. At all time periods, patients undergoing LDL-P measurement were more likely to receive intensive lipid-lowering therapy and had a lower risk of CHD/stroke than those in the LDL-C cohort (HR: 0.76; 95% CI: 0.61-0.96; at 12 months).

CONCLUSIONS

In this real-world sample of commercially insured patients, higher LDL-P levels were associated with increased CHD risk. Moreover, high-risk patients who achieved LDL-P <1000 nmol/L received more aggressive lipid-lowering therapy than patients achieving LDL-C <100 mg/dL, and these differences in lipids and therapeutic management were associated with a reduction in CHD/stroke events over 12, 24 and 36 months follow-up.

Reduction in dietary trans fat intake is associated with decreased LDL particle number in a primary prevention population

BACKGROUND AND AIMS

Increased trans fat intake has been associated with an increased risk of cardiovascular disease (CVD). While the effect of trans fat on traditional lipids is known, it's association with LDL particle number (LDL-P), a novel marker of CVD risk, has not been established. The purpose of this study was to determine the association between trans fat intake and LDL-P over 1-year among individuals participating in a lifestyle intervention trial.

METHODS AND RESULTS

Family members (N = 400, 33% male, mean age 48 ± 13) of patients hospitalized with CVD who participated in a 1-year randomized controlled primary prevention lifestyle intervention trial and had complete dietary data and LDL-P measures at baseline and 1-year. Change in trans fat as a percentage of total diet and mean absolute change in LDL-P at 1-year was assessed using multivariate adjusted linear regression models. At baseline, there was a significant positive correlation between dietary trans fat intake and LDL-P (Beta = 37, p = 0.04). For every 1 percent change in trans fat intake there was a 27 nmol/L change in LDL-P (Beta = 27, p = 0.04) over 1-year which was independent of baseline predictors and confounders (age, sex, smoking, statin use, waist size and physical activity; Beta = 30, p = 0.03).

CONCLUSION

A reduction in trans fat intake over 1-year was significantly associated with a reduction in LDL-P independent of potential confounders. Healthcare providers should reinforce the beneficial impact of a healthy diet, and in particular modifications in trans fat intake on improving lipid profiles.

Impact of physical activity and diet on lipoprotein particle concentrations in severely obese women participating in a 1-year lifestyle intervention

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Physical activity and high aerobic fitness protects against cardiovascular disease and early death, besides having a very modest impact on lipoprotein-cholesterol in obese subjects. Physical activity has been shown to favourably alter lipoprotein particle concentrations and apolipoprotein B with minimal weight loss in overweight to moderately obese subjects.

WHAT THIS STUDY ADDS

We studied the impact of physical activity on lipoprotein subclass particle concentrations in women with severe obesity. Increased physical activity duration was associated with favourable changes, whereas increased PA intensity was associated with adverse changes in some lipoprotein particle subclasses in severely obese women. Severely obese women that manage to increase their physical activity level can improve their lipoprotein profile, whether or not they lose fat mass Physical activity (PA) and high aerobic fitness protects against cardiovascular disease and early death possibly among others because of an anti-atherogenic impact on lipoprotein particle concentrations. The objective of this study was to determine the impact of PA and diet on lipoprotein particle concentrations. Thirty-one severely obese women (age 43.6 ± 10.2 years; body mass index 43.0 ± 6.3 kg m(-2) ) participated in a 1-year lifestyle intervention with repeated measurements of lipoprotein particle subclass concentrations and size of very low density lipoprotein (VLDL), low density lipoprotein (LDL) and high density lipoprotein (HDL), as well as fat mass, PA and diet. Multiple regression was used to determine associations with change (Δ) in two principal components (PCs) describing lipoprotein distributions: ΔPC 1 LIPO (dominated by VLDL and LDL) and ΔPC 2 LIPO (dominated by large HDL and mean HDL particle size). ΔPA duration was the only variable that was significantly related to ΔPC 1 LIPO (partial r = -0.40, P = 0.008), while ΔPA intensity was the only variable that was significantly related to ΔPC 2 LIPO (partial r = -0.43, P = 0.003) in adjusted models. Increased PA duration was associated with favourable changes, whereas increased PA intensity was associated with adverse changes in some lipoprotein particle subclasses in severely obese women.

Systematic review: Evaluating the effect of lipid-lowering therapy on lipoprotein and lipid values

PURPOSE

This systematic review was performed to summarize published experience using low density lipoprotein particle number (LDL-P) to monitor the efficacy of lipid-lowering pharmacotherapies.

METHODS

Studies were identified from a literature search of MEDLINE (January 1, 2000 - June 30, 2012); and abstract searches of select conferences. All accepted studies reported mean (or median) nuclear magnetic resonance (NMR)-based LDL-P values for at least 10 subjects receiving lipid lowering pharmacotherapy.

RESULTS

Searches revealed 36 studies (with 61 treatment arms) in which LDL-P measurements were reported pre- and post-treatment. Most studies also reported changes in low-density lipoprotein cholesterol (LDL-C), but fewer studies reported changes in apolipoprotein B (apoB)(n = 20) and non-HDL-C (n = 28). Treatments included statins (22 arms/15 studies), fibrates (7 arms/7 studies), niacin (7 arms/6 studies), bile acid sequestrants (5 arms/2 studies), an anti-apoB oligonucleotide (2 arms/2 studies), combination therapies (8 arms/6 studies), anti-diabetics (5 arms/4 studies), and, other treatments (5 arms/2 studies). Lipid-lowering pharmacotherapy resulted in reductions in mean LDL-P in all but two studies. In several statin studies, the percent reductions in LDL-P were smaller than reductions in LDL-C, comparable changes were reported when LDL-P and apoB, were reported.

CONCLUSIONS

Study-level data from this systemic review establish that different lipid lowering agents can lead to discordance between LDL-P and LDL-C, therefore, basing LDL-lowering therapy only on the achievement of cholesterol goals may result in a treatment gap. Therefore, the use of LDL-P for monitoring lipid-lowering therapy, particularly for statins, can provide a more accurate assessment of residual cardiovascular risk.

Effects of ezetimibe, simvastatin and ezetimibe/simvastatin on correlations between apolipoprotein B, LDL cholesterol and non-HDL cholesterol in patients with primary hypercholesterolemia

BACKGROUND/SYNOPSIS

Apolipoprotein (apo) B is highly predictive of coronary risk, especially in patients with high triglycerides (TG). This post hoc analysis evaluated the effects of lipid-lowering therapy on correlations between apoB and low-density lipoprotein cholesterol (apoB:LDL-C) and non-high-density lipoprotein cholesterol (apoB:non-HDL-C) in patients with TG< and ≥ 200 mg/dL.

METHODS

This analysis used data from 3 randomized clinical trials in patients with primary hypercholesterolemia receiving placebo, ezetimibe (EZE), simvastatin (SIMVA) or EZE/SIMVA for 12 weeks. Simple linear regression analyses predicted LDL-C and non-HDL-C levels corresponding to apoB values (80 mg/dL) at baseline and Week 12.

RESULTS

ApoB correlated with LDL-C (r ≥ 0.76) and non-HDL-C (r ≥ 0.86) at baseline. The correlations were strengthened with SIMVA and EZE/SIMVA at Week 12 (r ≥ 0.88 for LDL-C and r ≥ 0.94 for non-HDL-C). The predicted LDL-C and non-HDL-C values were lower following treatment with SIMVA or EZE/SIMVA than for placebo and EZE. For SIMVA and EZE/SIMVA, the predicted LDL-C and non-HDL-C values were closer to more aggressive LDL-C and non-HDL-C levels (i.e., 70 and 100 mg/dL, respectively). The apoB:LDL-C and apoB:non-HDL-C correlations were weaker and the predicted LDL-C values were generally lower in high TG patients than in low TG patients both at baseline and Week 12. In contrast, the predicted non-HDL-C values were generally higher in high versus low TG patients at baseline but less so at Week 12.

CONCLUSION

After treatment with EZE, SIMVA, or EZE/SIMVA, a given apoB value corresponds to lower LDL-C and non-HDL-C levels than those obtained from untreated patients.

Colesevelam improved lipoprotein particle subclasses in patients with prediabetes and primary hyperlipidaemia

BACKGROUND

A randomised, double-blind, placebo-controlled study evaluated lipid- and glucose-lowering effects of colesevelam in patients with prediabetes and primary hyperlipidaemia. We report the effect of colesevelam on lipoprotein particle concentration and particle size (determined by nuclear magnetic resonance spectroscopy) in these patients.

METHODS

Adults with prediabetes (World Health Organization criteria), low-density lipoprotein cholesterol (LDL-C) ≥ 100 mg/dL (≥2.6 mmol/L) and triglycerides < 500 mg/dL (<5.6 mmol/L) were randomised to colesevelam 3.75 g/day or placebo for 16 weeks. The intent-to-treat population comprised 103 colesevelam and 106 placebo recipients.

RESULTS

At the end of the study, mean reduction from baseline in total LDL particle concentration was significantly greater with colesevelam versus placebo (mean treatment difference: -113 nmol/L; p = 0.02). Increases in total very low-density lipoprotein particle concentration (VLDL-P) and high-density lipoprotein particle concentration (HDL-P) did not differ significantly between the groups; however, with colesevelam versus placebo, there were significantly (p < 0.05) greater increases in large and medium VLDL-P and large HDL-P and reductions in small VLDL-P. Mean size increases were significantly greater with colesevelam for VLDL (mean treatment difference: 5.3 nm; p < 0.0001) and HDL (0.1 nm; p = 0.002).

CONCLUSIONS

Colesevelam improved the overall atherogenic lipoprotein profile in adults with prediabetes and primary hyperlipidaemia, despite potentially less favourable changes in VLDL particles.

Role of sirtuin 1 in the regulation of hepatic gene expression by thyroid hormone

Sirtuin 1 (SIRT1) is a nuclear deacetylase that modulates lipid metabolism and enhances mitochondrial activity. SIRT1 targets multiple transcription factors and coactivators. Thyroid hormone (T(3)) stimulates the expression of hepatic genes involved in mitochondrial fatty acid oxidation and gluconeogenesis. We reported that T(3) induces genes for carnitine palmitoyltransferase (cpt1a), pyruvate dehydrogenase kinase 4 (pdk4), and phosphoenolpyruvate carboxykinase (pepck). SIRT1 increases the expression of these genes via the activation of several factors, including peroxisome proliferator-activated receptor α, estrogen-related receptor α, and peroxisome proliferator-activated receptor γ coactivator (PGC-1α). Previously, we reported that PGC-1α participates in the T(3) induction of cpt1a and pdk4 in the liver. Given the overlapping targets of T(3) and SIRT1, we investigated whether SIRT1 participated in the T(3) regulation of these genes. Resveratrol is a small phenolic compound whose actions include the activation of SIRT1. Addition of resveratrol increased the T(3) induction of the pdk4 and cpt1a genes in hepatocytes. Furthermore, expression of SIRT1 in hepatocytes mimicked resveratrol in the regulation of gene expression by T(3). The deacetylase activity of SIRT1 was required and PGC-1α was deacetylated following addition of T(3). We found that SIRT1 interacted directly with T(3) receptor (TRβ). Knockdown of SIRT1 decreased the T(3) induction of cpt1a and pdk4 and reduced the T(3) inhibition of sterol response element binding protein (srebp-1c) both in isolated hepatocytes and in rat liver. Our results indicate that SIRT1 contributes to the T(3) regulation of hepatic genes.

Is combination therapy an effective way of reaching lipid goals in type 2 diabetes mellitus?

Type 2 diabetes mellitus is associated with a specific pattern of plasma lipid and lipoprotein abnormalities. Lipid goals are often not attained with statins alone, and combination lipid-lowering strategies may need to be considered in an attempt to further reduce the residual cardiovascular risk. Combination therapy utilizes various classes of lipid-lowering medications with different mechanisms of action and different effects on lipid levels. Clinical trial data support the efficacy of combining statins with fibrates, niacin, ezetimibe (cholesterol absorption inhibitor) and colesevelam (bile acid sequestrant) with the caveat that there are insufficient clinical trial data to show a further robust benefit on cardiovascular outcomes. Of the different combination therapy options to potentiate low-density lipoprotein cholesterol lowering in combination with a statin, colesevelam provides additional beneficial effects by further reducing hemoglobin A1c levels in Type 2 diabetes mellitus.

Hypertriglyceridemia and residual dyslipidemia in statin-treated, patients with diabetes at the highest risk for cardiovascular disease and achieving very-low low-density lipoprotein-cholesterol levels

BACKGROUND

As the result of the high prevalence of comorbidities and conventional risk factors among patients with type 2 diabetes (T2DM), most patients belong to the highest cardiovascular disease risk category, and have a target low-density lipoprotein cholesterol (LDL-C) of <70 mg/dL. Because substantial residual risk persists at LDL-C <70 mg/dL, a more comprehensive control of non-LDL-C and particles was recommended in the joint 2008 American Diabetes Association/American College of Cardiology Consensus.

OBJECTIVE

To ascertain, in statin-treated T2DM patients belonging to this greatest-risk group, with on-statin LDL-C <70 mg/dL, (1) the proportion of patients meeting all three critical levels (LDL-C <70 mg/dL, non-high-density lipoprotein cholesterol [HDL-C] <100 mg/dL, apoB <80 mg/dL) and (2) the variables associated with target attainment versus nonattainment.

PATIENTS AND METHODS

Among 675 unselected patients with T2DM, 367 were both at very high cardiometabolic risk and taking statins; 118 of these patient had LDL-C levels <70 mg/dL. Patients meeting all three criteria (LDL-C, non-HDL-C, and apoB; n = 79; all three at goal group) were compared with those only reaching LDL-C (n = 49; only LDL-C at goal group).

RESULTS

LDL-C was 54 (12) for the all three at goal group versus 57 (10) mg/dL for the only LDL-C at goal group (NS). The two groups were similar regarding age, gender, diabetes duration, body mass index, waist circumference, blood pressure, renal function and micro-/macroangiopathy prevalence. A statin plus fibrate was given to 16% of patients in the all three at goal group and 32% in the only LDL-C at goal group. The two groups did not differ in baseline (prestatin) LDL-C, HDL-C, and non-HDL-C, except for pre-/post-lipid-lowering drug(s) triglycerides (TG): 177 (95)/118 (56) for all three at goal versus 279 (134)/ 241 (103) mg/dL for only LDL-C at goal (P = .0230 and P = .0001). The only LDL-C at goal group had lower HDL-C (vs. all three at goal): 41 (12) vs. 47 (14) mg/dL (P = .0237), with atherogenic dyslipidemia [hypo-HDL-C + hyper-TG] prevalence of 35% in the all three at goal versus 56% in the only LDL-C at goal group (P < .0001). log(TG)/HDL-C was 0.049 (0.021) for all three at goal versus 0.063 (0.021) for only LDL-C at goal (P < .0001). The LDL-C/apoB ratio was 0.92 (0.24) for all three at goal vs. 0.67 (0.18) for only LDL-C at goal (P < .0001), suggestive of smaller/denser LDL.

CONCLUSION

The presence of atherogenic dyslipidemia was associated with a failure to meet all three critical modifiable targets for hypercholesterolemia, such a nonachievement being found in a large proportion (one-third) of very-high risk T2DM patients with very-low on-statin LDL-C. Attainment of all three targets will require (1) titration/permutation of statins, (2) lifestyle (re)inforcement; and/or (3) statin-fibrate bitherapy.

Clinical utility of inflammatory markers and advanced lipoprotein testing: advice from an expert panel of lipid specialists

The National Cholesterol Education Program Adult Treatment Panel guidelines have established low-density lipoprotein cholesterol (LDL-C) treatment goals, and secondary non-high-density lipoprotein (HDL)-C treatment goals for persons with hypertriglyceridemia. The use of lipid-lowering therapies, particularly statins, to achieve these goals has reduced cardiovascular disease (CVD) morbidity and mortality; however, significant residual risk for events remains. This, combined with the rising prevalence of obesity, which has shifted the risk profile of the population toward patients in whom LDL-C is less predictive of CVD events (metabolic syndrome, low HDL-C, elevated triglycerides), has increased interest in the clinical use of inflammatory and lipid biomarker assessments. Furthermore, the cost effectiveness of pharmacological intervention for both the initiation of therapy and the intensification of therapy has been enhanced by the availability of a variety of generic statins. This report describes the consensus view of an expert panel convened by the National Lipid Association to evaluate the use of selected biomarkers [C-reactive protein, lipoprotein-associated phospholipase A(2), apolipoprotein B, LDL particle concentration, lipoprotein(a), and LDL and HDL subfractions] to improve risk assessment, or to adjust therapy. These panel recommendations are intended to provide practical advice to clinicians who wrestle with the challenges of identifying the patients who are most likely to benefit from therapy, or intensification of therapy, to provide the optimum protection from CV risk.

Reducing vascular events risk in patients with dyslipidaemia: an update for clinicians

Reducing the risk of vascular events in patients with dyslipidaemia requires cardiovascular disease risk stratification and lifestyle/pharmacological intervention on modifiable risk factors. Reduction of low-density lipoprotein cholesterol (LDL-C) with statins is highly effective in reducing cardiovascular disease in patients with and without diabetes, but leaves unaddressed a sizeable residual vascular risk (RvR), which is rarely quantified in routine clinical practice. Such RvR may relate to lack of strict target attainment for all atherogenic variables [LDL-C, non-high-density lipoprotein cholesterol (HDL-C) and/or apolipoprotein B(100)]. Another substantial lipid-related and modifiable RvR component is related to atherogenic dyslipidaemia, especially as global rates of obesity, type 2 diabetes and metabolic syndrome are increasing. Atherogenic dyslipidaemia is associated with insulin-stimulated very-low-density lipoprotein overproduction and reduced reverse cholesterol transport. The hallmark of atherogenic dyslipidaemia is the coexistence of low HDL-C and elevated triglycerides. Therapeutic lifestyle changes and combination lipid-lowering therapy with drugs targeting atherogenic dyslipidaemia (such as fibrates or innovative drugs targeting atherogenic dyslipidaemia and/or apolipoprotein B(100) metabolism) on top of background statins, have a potential to reduce RvR in high-risk groups, as shown in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial, in which combination therapy with simvastatin plus fenofibrate decreased macrovascular risk in patients with diabetes and atherogenic dyslipidaemia, and retinopathy risk irrespective of baseline lipids.

Achievement of lipid targets with the combination of rosuvastatin and fenofibric Acid in patients with type 2 diabetes mellitus

Objective

The objective of this study was to assess the proportion of patients with type 2 diabetes mellitus (T2DM) attaining individual and combined targets of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), non-HDL-C, and apolipoprotein B (ApoB) after treatment with rosuvastatin (R) + fenofibric acid (FA) compared with corresponding-dose R monotherapy.

Methods

This post hoc analysis evaluated data from the T2DM subset of patients with mixed dyslipidemia (LDL-C ≥130 mg/dL, HDL-C <40/50 mg/dL in men/women, and TG ≥150 mg/dL) from 2 randomized studies. Patients included in the analysis (N = 456) were treated with R (5, 10, or 20 mg), FA 135 mg, or R (5, 10, or 20 mg) + FA 135 mg for 12 weeks. Attainment of LDL-C <100 mg/dL, HDL-C >40/50 mg/dL in men/women, TG <150 mg/dL, non-HDL-C <130 mg/dL, ApoB <90 mg/dL, and the combined targets of these parameters was assessed.

Results

Treatment with R + FA resulted in a significantly higher proportion of patients achieving optimal levels of HDL-C (46.8% vs. 20.8%, P = 0.009 for R 10 mg + FA), TG (60.0% vs. 34.0%, P = 0.02 for R 10 mg + FA; 54.0% vs. 26.4%, P = 0.005 for R 20 mg + FA), non-HDL-C (55.1% vs. 36.4%, P = 0.04 for R 5 mg + FA), ApoB (58.0% vs. 36.4%, P = 0.02 for R 5 mg + FA); and the combined targets of LDL-C, HDL-C, and TG (28.3% vs. 8.3%, P = 0.02 for R 10 mg + FA) and all 5 parameters (26.1% vs. 8.3%, P = 0.03 for R 10 mg + FA) than corresponding-dose R monotherapies.

Conclusions

A significantly greater proportion of T2DM patients achieved individual and combined lipid targets when treated with the combination of R + FA than corresponding-dose R monotherapies.

Becoming more focused therapeutic lipid patterns: results from the Hungarian MULTI GAP 2010

Previous studies have found that many high-risk patients are not achieving their LDL-cholesterol goals, and many patients, despite being treated with lipid-lowering therapy, also have elevated triglycerides and/or low levels of HDL-cholesterol. Aims: Authors analyzed the treatment strategies for dyslipidemic subjects following cardiovascular events similarly to their former survey from 2008 and 2009. Methods: In the MULTI GAP (MULTI Goal Attainment Problem) 2010 trial data from standard and structured questionnaires of 2332 patients were processed. Authors analyzed the proportion of the patients reaching target levels for total cholesterol, LDL-C, HDL-C, A-C (atherogen cholesterol) and triglyceride. Results: 15% (n = 355) of the patients did not receive any lipid lowering treatment. 44% of the patients treated by specialists reached the target LDL-C level of 2.5 mmol/l. In „high risk” group target levels for HDL-C were reached by 61% of the patients, and for triglyceride by 43% of the subjects. 43% of the patients with the best compliance (>90%) reached the target LDL-C level of 2.5 mmol/l. Conclusion: There is a need for more effective lipid lowering therapy with more frequent use of higher doses of statins or combinations of lipid lowering drugs. Orv. Hetil., 2011, 152, 822–827.

log(TG)/HDL-C is related to both residual cardiometabolic risk and β-cell function loss in type 2 diabetes males

Background

T2DM is associated with atherogenic dyslipidemia (AD), defined as decreased HDL-C plus raised triglycerides (TG). AD confers increased risk for CAD, even when LDL-C is at target. AD is rarely assessed due to lack of screening methods consensus.

Aim

To establish the prevalence and severity of AD from log(TG)/HDL-C in T2DM males, and to determine how it relates to cardiometabolic phenotype, glucose homeostasis, micro- and macrovascular complications, and 10-year UKPDS CV risk.

Methods

585 T2DM males divided according to quintiles (Q) of log(TG)/HDL-C. AD prevalence defined as HDL-C <40 mg.dL^-1 plus TG ≥150 mg.dL^-1. β-cell function assessed with HOMA.

Results

Mean HDL-C and TG were 44 (13) and 204 (155) mg.dL^-1. AD prevalence was 35%. AD correlated with lower β-cell function, with accelerated loss of insulin secretion, and with poorer HbA_1c levels. AD was related to a high prevalence of CAD, and also to 10-year absolute CAD risk.

Conclusions

log(TG)/HDL-C is a simple means to estimate AD and the residual CV risk it confers in T2DM. AD closely associates with major cardiometabolic and glucose homeostasis determinants and poorer metabolic control. The ratio also relates to macroangiopathy prevalence and ranks future CAD risk, and is well-suited to capture non-LDL-related macrovascular residual risk and major glycemic determinants.