Remnant cholesterol as a cause of ischemic heart disease: Evidence, definition, measurement, atherogenicity, high risk patients, and present and future treatment

Biochemical risk factors of atherosclerotic cardiovascular disease: from a narrow and controversial approach to an integral approach and precision medicine

INTRODUCTION

Guidelines of management of dyslipidemias and prevention of cardiovascular disease (CVD) are based on firm scientific evidence obtained by randomized controlled trials (RCTs). However, the role of elevated low-density lipoprotein-cholesterol (LDL-C)as a risk factor of CVD and therapies to lower LDL-C are frequently disputed by colleagues who disagree with the conclusions of the RCTs published. This review focuses on this dispute, and evaluates the current approach of management of dyslipidemias and CVD prevention to find modern alternatives for more precise diagnosis and therapy of dyslipidemic patients.

AREAS COVERED

Recent interest in lipoprotein(a) (Lp(a)) and remnants lipoproteins and in therapies that do not influence LDL-C levels primarily, such as anti-inflammatory drugs and icosapent ethyl, has revitalized our concern to optimize the care for patients with increased CVD risk without focusing simply on reduction of LDL-C by therapy with statins, ezitemibe, and proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors.

EXPERT OPINION

The limited characterization of study populations by measurement of total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C) and triglycerides (TG) followed by measurement or calculation of LDL-C should be extended by a more integral approach in order to realize precision diagnostics and precision medicine, for the sake of personalized patient care.

Comparison of low-density lipoprotein cholesterol level calculated using the modified Martin/Hopkins estimation or the Friedewald formula with direct homogeneous assay measured low-density lipoprotein cholesterol

INTRODUCTION

Low-density lipoprotein cholesterol (LDL-C) represents the primary lipoprotein target for reducing cardiovascular risk (CV). The aim of our study is to compare the direct and the calculated LDL-C levels in the range below 1.8 mmol/l and 2.6 mmol/l depending on triglycerides, and to evaluate the variation in remnant lipoprotein cholesterol.

MATERIAL AND METHODS

We investigated 14 906 lipid profiles from fasting blood samples of Hungarian individuals with triglycerides < 4.5 mmol/l. Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG) and direct LDL-C were measured by the enzymatic assay. We calculated LDL-C by Friedewald's formula (F-LDL-C) and by using the new Martin/Hopkins estimation (MH-LDL-C).

RESULTS

For F-LDL-C below 1.8 mmol/l, MH-LDL-C was 58% between 1.8 and 2.59 mmol/l when TG was in the range 2.3-4.5 mmol/l. For F-LDL-C below 2.6 mmol/l, the MH-LDL-C concordance was 73% in the same TG range (2.3-4.5 mmol/l. If MH-LDL-C was less than 1.8 mmol/l or between 1.8 and 2.59 mmol/l, the difference between non-HDL-C (TC - HDL-C = AC: atherogenic cholesterol) and (MH)LDL-C was less than 0.8 mmol/l in the TG range below 2.3 mmol/l. The remnant lipoprotein cholesterol values were on average 0.5 mmol/l lower by the Martin/Hopkins estimation compared to the Friedewald's calculation if the TG was above 2.3 mmol/l.

CONCLUSIONS

The Friedewald equation tends to underestimate LDL-C levels in very high and high-risk settings. Our analysis supports the conclusion that in Hungarian patients, LDL-C estimation using the Martin/Hopkins formula, which is validated by the beta-quantification method, yields a more accurate LDL-C value than that calculated by the Friedewald formula.

The association of remnant cholesterol (RC) and interaction between RC and diabetes on the subsequent risk of hypertension

PURPOSE

Whether elevated remnant cholesterol (RC) is associated with hypertension (HTN) and whether elevated RC interacts with diabetes on the subsequent risk of HTN have not been illustrated. Thus, this study is aimed to investigate the associations and interactions of RC, diabetes, and the management of cardiovascular risk factors with the risk of incident HTN in a Chinese population.

PATIENTS AND METHODS

This cohort study included 42,994 individuals who participated in the routine health check-up from April 2016 to August 2020 and follow-ups from April 2017 to August 2021 at the Medical Examination Center of Beijing Chao-Yang Hospital. RC was divided into quintiles as follows: the < 20% group, the 20-39% group, the 40-59% group, the 60-79% group, and the ≥ 80% group. This study finally included 17,006 participants who were free from HTN at baseline.

RESULTS

This study had 1,861 (10.90%) HTN occurred, 205 (5.30%) in the first quintile of RC, 335 (8.98%) in the second quintile of RC, 388 (11.17%) in the third quintile of RC, 420 (13.42%) in the fourth quintile of RC, and 513 (17.91%) in the fifth quintile of RC. Compared with participants in the first quintile of RC, participants in the fifth quintile of RC showed a greater risk of HTN events among participants with diabetes [hazard ratio (HR), 4.95; 95% confidence interval (CI), 1.05-23.39; P = 0.0432) than among participants without diabetes (HR, 1.67; 95% CI, 1.26-2.22, P = 0.0004; P for interaction = 0.0420). Compared with participants without diabetes, participants with diabetes who have the ideal management of RC and other risk factors showed no excess risk of HTN.

CONCLUSIONS

Elevated RC is significantly predictive of HTN among the diabetic population. RC and diabetes interacted with each other on the subsequent risk of HTN, and the desired management of RC, glucose, and cardiovascular risk factors on HTN risk was quite favorable.

Association of Increased Remnant Cholesterol and the Risk of Coronary Artery Disease: A Retrospective Study

Background and Aims: Low-density lipoprotein cholesterol (LDL-C) is the primary target of lipid-lowering therapy in coronary artery disease (CAD). But some patients with the normal levels of LDL-C still suffer from CAD progression and malignant outcomes (e.g., major adverse cardiovascular events [MACEs]), and the mechanism is unclear. The previous prospective studies demonstrated that the remnant cholesterol (RC) and non-high-density lipoprotein cholesterol (non-HDL-C) were capable to predict the risk of CAD. This study evaluated the association between RC and non-HDL-C with the risk of CAD.

Methods: In our study, 12,563 patients were enrolled. We categorized patients into four concordance/discordance groups according to the median of RC, LDL-C, and non-HDL-C. Then, we performed a propensity score matching (PSM) strategy. The unadjusted and adjusted multivariate logistic regression models were used to evaluate the relationship between the lipid concentrations.

Results: In this study, 8,658 (68.9%) patients were male with a median age of 61 (54 and 67) years. The multivariate logistic regression showed the odds ratio (OR) of RC was 1.952 (CI = 1.276–2.988, p = 0.002). The OR of the low RC/high LDL-C group was 0.626 (CI = 0.504–0.778, p < 0.001) and the OR of the low RC/high non-HDL-C group was 0.574 (CI = 0.462–0.714, p < 0.001). The p-values for interaction between the RC and hypertension, diabetes were both < 0.001.

Conclusion: Our study showed a significant association between the RC and CAD. The level of RC was more capable to reflect the risk of CAD than LDL-C and non-HDL-C. There was an interaction relationship between RC and age, gender, hypertension, diabetes, in CAD. But we did not find whether there was a relationship between the non-HDL-C and CAD.

Association between remnant cholesterol and arterial stiffness: A secondary analysis based on a cross-sectional study

The relationship between conventional lipid parameters and arterial stiffness (AS) has been verified by previous studies. However, it remains unknown whether non‐conventional lipid parameters have certain predictive effect on AS represented by brachial‐ankle pulse wave velocity (baPWV). Therefore, the study was to explore the relationship between remnant cholesterol (RC) and other non‐conventional lipid parameters and AS in the general population free from cardiovascular disease. The study included 912 participants aged 24–84 years from a medical health checkup center of Murakami Memorial Hospital. Logistic regression analysis and receiver operating characteristic (ROC) curves were used to examine the association between non‐conventional lipid parameters and AS. The results showed that compared with non‐AS group, the AS group had higher RC, non‐high‐density lipoprotein cholesterol (Non‐HDL‐C), atherogenic index of plasma (AIP), lipoprotein combine index (LCI), atherosclerosis index (AI), triglycerides/HDL‐C (TG/HDL‐C), Castelli's risk index I (CRI‐I) and Castelli's risk index II (CRI‐II). Then, the authors divided participants into two groups by the optimal cutoff point of 23.6 of RC determined by Youden index. The baPWV was significantly higher in higher RC group compared with lower RC group, and RC was positively correlated with baPWV. Multivariate Logistic regression analysis showed that, regarding lower RC as reference, higher RC was independently associated with higher risk of AS, independent of other risk factors (OR = 1.794, 95% CI: 1.267‐2.539, p = .001). The area under the curve of AS predicted by RC was higher than that of other non‐conventional lipid parameters (almost all p < .05). The findings indicated that increased RC was a significant predictor of AS.

The Effects of Calculated Remnant-Like Particle Cholesterol on Incident Cardiovascular Disease: Insights from a General Chinese Population

Background: Growing evidence suggests that remnant cholesterol (RC) contributes to residual atherosclerotic cardiovascular disease (ASCVD) risk. However, the cutoff points to treat RC for reducing ASCVD are still unknown. This study aimed to investigate the relationships between RC and combined cardiovascular diseases (CVDs) in a general China cohort, with 11,956 subjects aged ≥ 35 years. Methods: Baseline RC was estimated with the Friedewald formula for 8782 subjects. The outcome was the incidence of combined CVD, including fatal and nonfatal stroke and coronary heart disease (CHD). The Cox proportional hazards model was used to calculate hazard ratios (HRs) with 95% confidence intervals. The restricted cubic spline (RCS) model was used to evaluate the dose–response relationship between continuous RC and the natural log of HRs. Results: After a median follow-up of 4.66 years, 431 CVD events occurred. In the Cox proportional models, participants with a high level of categorial RC had a significantly higher risk for combined CVD (HR: 1.37; 95% CI: 1.07–1.74) and CHD (HR: 1.63; 95% CI: 1.06–2.53), compared to those with a medium level of RC. In the stratification analyses, a high level of RC significantly increased combined CVD risk for subgroups females, age < 65 years, noncurrent smokers, noncurrent drinkers, normal weight, renal dysfunction, and no hyperuricemia. The same trends were found for CHD among subgroups males, age < 65 years, overweight, renal dysfunction, and no hyperuricemia; stroke among subgroup females. In RCS models, a significant linear association between RC and combined CVD and a nonlinear association between RC and CHD resulted. The risk of outcomes was relatively flat until 0.84 mmol/L of RC and increased rapidly afterwards, with an HR of 1.308 (1.102 to 1.553) for combined CVD and 1.411 (1.061 to 1.876) for CHD. Stratified analyses showed a significant nonlinear association between RC and CVD outcomes in the subgroup aged < 65 years or the diabetes subgroup. Conclusions: In this large-scale and long-term follow-up cohort study, participants with higher RC levels had a significantly worse prognosis, especially for the subgroup aged 35–65 years or the diabetes mellitus subgroup.

Comparison of the effectiveness of Martin's equation, Friedewald's equation, and a Novel equation in low-density lipoprotein cholesterol estimation

Low-density-lipoprotein cholesterol (LDL-C) is the main target in atherosclerotic cardiovascular disease (ASCVD). We aimed to validate and compare a new LDL-C estimation equation with other well-known equations. 177,111 samples were analysed from two contemporary population-based cohorts comprising asymptomatic Korean adults who underwent medical examinations. Performances of the Friedewald (FLDL), Martin (MLDL), and Sampson (SLDL) equations in estimating direct LDL-C by homogenous assay were assessed by measures of concordance (R2, RMSE, and mean absolute difference). Analyses were performed according to various triglyceride (TG) and/or LDL-C strata. Secondary analyses were conducted within dyslipidaemia populations of each database. MLDL was superior or at least similar to other equations regardless of TG/LDL-C, in both the general and dyslipidaemia populations (RMSE = 11.45/9.20 mg/dL; R2 = 0.88/0.91; vs FLDL: RMSE = 13.66/10.42 mg/dL; R2 = 0.82/0.89; vs SLDL: RMSE = 12.36/9.39 mg/dL; R2 = 0.85/0.91, per Gangnam Severance Hospital Check-up/Korea Initiatives on Coronary Artery Calcification data). MLDL had a slight advantage over SLDL with the lowest MADs across the full spectrum of TG levels, whether divided into severe hyper/non-hyper to moderate hypertriglyceridaemia samples or stratified by 100-mg/dL TG intervals, even up to TG values of 500-600 mg/dL. MLDL may be a readily adoptable and cost-effective alternative to direct LDL-C measurement, irrespective of dyslipidaemia status. In populations with relatively high prevalence of mild-to-moderate hypertriglyceridaemia, Martin's equation may be optimal for LDL-C and ASCVD risk estimation.

Associations between remnant lipoprotein cholesterol and central systolic blood pressure in a Chinese community-based population: a cross-sectional study

Background

The lipid profile is reportedly related to peripheral blood pressure or pulse wave velocity. However, no studies have investigated the associations between lipid parameters, especially remnant lipoprotein cholesterol (RLP-C), and central systolic blood pressure (cSBP).

Methods

This study used baseline data of a community-based cohort in Beijing, China. Participants who had been treated with anti-hypertensive or lipid-lowering agents were excluded. RLP-C is equal to total cholesterol (TC) minus the sum of low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C). An Omron HEM-9000AI device was used to measure non-invasive cSBP. The associations between blood lipid profile and non-invasive cSBP were evaluated using multivariable regression models.

Results

The 5173 included participants were 55.0 ± 8.5 years old; 35.7% (1845) of participants were men. Increased cSBP was significantly associated with increased TC, LDL-C, non-high-density lipoprotein cholesterol (non-HDL-C), triglyceride (TG), and RLP-C but with decreased HDL-C, even after adjusting for possible covariates. When simultaneously entering individual pairs of RLP-C and other blood lipid parameters into the multivariable regression model, RLP-C remained significantly associated with cSBP, even after adjusting for other lipids. Compared with participants who had RLP-C levels in the first quartile (Q1), cSBP for those with RLP-C in Q4 was increased to 4.57 (95% confidence interval [CI]: 3.08–6.06) mmHg after adjusting for LDL-C, 4.50 (95%CI: 2.98–6.02) mmHg after adjusting for TC, 3.91 (95%CI: 1.92–5.89) mmHg after adjusting for TG, 5.15 (95%CI: 3.67–6.63) mmHg after adjusting for HDL-C, and 4.10 (95%CI: 2.36–5.84) mmHg after adjusting for non-HDL-C.

Conclusions

Increased blood RLP-C level was significantly associated with higher cSBP in a Chinese population, independently of other lipids, which indicates its importance in individual cardiovascular risk assessment.

ApoB-lipoprotein remnant dyslipidemia and high-fat meal intolerance is associated with markers of cardiometabolic risk in youth with obesity

INTRODUCTION

Cardiovascular disease (CVD) originates in childhood and risk is exacerbated in obesity. Mechanisms of the etiologic link between early adiposity and CVD-risk remain unclear. Postprandial or non-fasting dyslipidemia is characterized by elevated plasma triglycerides (TG) and intestinal-apolipoprotein(apo)B48-remnants following a high-fat meal and is a known CVD-risk factor in adults. The aim of this study was to determine (a) whether the fasting concentration of apoB48-remnants can predict impaired non-fasting apoB48-lipoprotein metabolism (fat intolerance) and (b) the relationship of these biomarkers with cardiometabolic risk factors in youth with or without obesity.

METHODS

We assessed fasting and non-fasting lipids in youth without obesity (n = 22, 10 males, 12 females) and youth with obesity (n = 13, 5 males, 8 females) with a mean BMI Z-score of 0.19 ± 0.70 and 2.25 ± 0.31 (P = .04), respectively.

RESULTS

Fasting and non-fasting apoB48-remnants were elevated in youth with obesity compared to youth without obesity (apoB48: 18.04 ± 1.96 vs 8.09 ± 0.59, P < .0001, and apoB48_AUC : 173.0 ± 20.86 vs 61.99 ± 3.44, P < .001). Furthermore, fasting plasma apoB48-remnants were positively correlated with the non-fasting response in apoB48_AUC (r = 0.84, P < .0001) as well as other cardiometabolic risk factors including HOMA-IR (r = 0.61, P < .001) and leptin (r = 0.56, P < .0001).

CONCLUSION

Fasting apoB48-remnants are elevated in youth with obesity and predict apoB48 postprandial dyslipidemia. ApoB48-remnants are associated with the extent of fat intolerance and appear to be potential biomarker of CVD-risk in youth.

Effects of evolocumab in individuals with type 2 diabetes with and without atherogenic dyslipidemia: An analysis from BANTING and BERSON

Background

Atherogenic dyslipidemia (AD), characterized by increased concentrations of apolipoprotein B (ApoB)-containing particles, is often present in individuals with type 2 diabetes mellitus (T2DM). Non-high-density lipoprotein cholesterol (non-HDL-C), cholesterol transported by apolipoprotein B (ApoB)-containing particles), and total apoB are considered secondary goals of lipid-lowering therapy to guide treatment of residual cardiovascular risk. The BANTING and BERSON studies demonstrated that evolocumab added to statin therapy reduced atherogenic lipid and lipoproteins concentrations in patients with T2DM.

Methods

This post-hoc analysis combined data from two randomized, placebo-controlled trials, BANTING and BERSON, to investigate the effect of evolocumab (140 mg every two weeks [Q2W] or 420 mg monthly [QM]) on atherogenic lipid (LDL-C, non-HDL-C, VLDL-C, remnant cholesterol) and lipoproteins (ApoB, lipoprotein(a) (Lp[a])), and achievement of 2019 European Society of Cardiology/European Atherosclerosis Society lipid treatment goals in individuals with and without AD.

Results

In individuals with high TGs with (n = 389) and without (n = 196) AD receiving background statin therapy, evolocumab, compared with placebo, substantially reduced the cholesterol levels from all ApoB atherogenic lipoproteins (least squares (LS) mean LDL-C by 66.7% to 74.3%, non-HDL-C by 53.4% to 65.8%, median remnant cholesterol by 28.9% to 34.2%, VLDL-C by 16.1% to 19.6%) and median TGs levels (by 17.5% to 19.6%) at the mean of weeks 10 and 12. LS mean ApoB was significantly reduced by 41.5% to 56.6% at week 12. Results were consistent in diabetic individuals with normal TGs (n = 519). Evolocumab was also associated with a significant reduction in median Lp(a) by 35.0% to 53.9% at the mean of weeks 10 and 12. A majority (74.7% to 79.8%) of evolocumab-treated individuals achieved the goal of both an LDL-C < 1.4 mmol/L and an LDL-C reduction of at least 50%, > 75% achieved non-HDL-C < 2.2 mmol/L at the mean of weeks 10 and 12, and > 67% achieved ApoB < 65 mg/dL at week 12.

Conclusions

Evolocumab effectively reduced LDL-C, non-HDL-C, ApoB, Lp(a), and remnant cholesterol in individuals with T2DM with and without AD. Evolocumab Q2W or QM enabled most individuals at high/very-high cardiovascular disease risk to achieve their LDL-C, non-HDL-C, and ApoB recommended goals.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01287-6.

Remnant Cholesterol and Common Carotid Artery Intima-Media Thickness in Patients With Ischemic Stroke

BACKGROUND

Remnant cholesterol makes great contribution to residual risk of cardiovascular disease, but population-based evidence on the relationship between remnant cholesterol and atherosclerosis is rare. Common carotid artery intima-media thickness (cIMT) is an imaging marker of subclinical atherosclerosis. We aimed to explore the association between remnant cholesterol levels and cIMT in patients with ischemic stroke.

METHODS

One thousand four hundred ninety-six ischemic stroke patients with baseline serum lipids and carotid artery imaging data were included in this analysis. Fasting remnant cholesterol was calculated as total cholesterol minus HDL (high-density lipoprotein) cholesterol minus LDL (low-density lipoprotein) cholesterol. Abnormal cIMT was defined as mean cIMT and maximum cIMT value ≥1 mm. Logistic regression and restricted cubic spline models were used to assess the relationships between remnant cholesterol levels and abnormal cIMT.

RESULTS

The multivariable-adjusted odds ratios (95% CIs) for the highest versus lowest quartile of remnant cholesterol were 2.06 (1.46-2.91) for abnormal mean cIMT and 1.70 (1.23-2.35) for abnormal maximum cIMT. There were linear associations between remnant cholesterol levels and both abnormal mean cIMT (P for linearity, <0.001) and abnormal maximum cIMT (P for linearity, 0.003). Moreover, the remnant cholesterol-cIMT association remained significant in the subsample of patients with optimal LDL cholesterol levels (n=179).

CONCLUSIONS

Elevated fasting remnant cholesterol levels were positively associated with mean cIMT and maximum cIMT in patients with ischemic stroke, even in patients with optimal LDL cholesterol levels. Future prospective studies are needed to verify our findings and to assess the effect of remnant cholesterol-lowering interventions in patients with ischemic stroke.

The Time Has Come for Quantitative Protein Mass Spectrometry Tests That Target Unmet Clinical Needs

Protein mass spectrometry (MS) is an enabling technology that is ideally suited for precision diagnostics. In contrast to immunoassays with indirect readouts, MS quantifications are multiplexed and include identification of proteoforms in a direct manner. Although widely used for routine measurements of drugs and metabolites, the number of clinical MS-based protein applications is limited. In this paper, we share our experience and aim to take away the concerns that have kept laboratory medicine from implementing quantitative protein MS. To ensure added value of new medical tests and guarantee accurate test results, five key elements of test evaluation have been established by a working group within the European Federation for Clinical Chemistry and Laboratory Medicine. Moreover, it is emphasized to identify clinical gaps in the contemporary clinical pathways before test development is started. We demonstrate that quantitative protein MS tests that provide an additional layer of clinical information have robust performance and meet long-term desirable analytical performance specifications as exemplified by our own experience. Yet, the adoption of quantitative protein MS tests into medical laboratories is seriously hampered due to its complexity, lack of robotization and high initial investment costs. Successful and widespread implementation in medical laboratories requires uptake and automation of this next generation protein technology by the In-Vitro Diagnostics industry. Also, training curricula of lab workers and lab specialists should include education on enabling technologies for transitioning to precision medicine by quantitative protein MS tests.

Triglycerides and risk of atherosclerotic cardiovascular disease: An update

Low-density lipoprotein cholesterol is a well-known causal factor for atherosclerotic cardiovascular disease, and is the primary target of lipid-lowering therapy. There is, however, still a substantial risk of atherosclerotic cardiovascular disease events despite intensive statin therapy, and data from clinical trials suggest that an elevated concentration of triglycerides is a marker of residual cardiovascular risk on low-density lipoprotein-lowering therapy. Serum triglycerides are a biomarker for triglyceride-rich lipoproteins, and several lines of evidence indicate that triglyceride-rich lipoproteins and their cholesterol-enriched remnant particles are associated with atherogenesis. Moreover, genetic data in humans strongly suggest that the remnants of triglyceride-rich lipoproteins are a causal cardiovascular risk factor. Although lifestyle changes remain the cornerstone of management of hypertriglyceridaemia, a recent trial with high doses of the omega-3 fatty acid icosapent ethyl showed a significant reduction in cardiovascular events that was not explained by the reduction in triglycerides alone. In patients with elevated triglycerides, several novel drugs are in development to reduce the residual risk on statin therapy linked to an excess of atherogenic triglyceride-rich lipoproteins. In this review, we provide an update on the biology, epidemiology and genetics of triglycerides, and the risk of atherosclerotic cardiovascular disease.

Fasted exercise does not improve postprandial lipemia responses to different meals in lean and obese subjects: A crossover, randomized clinical trial

INTRODUCTION

Persistent episodes of postprandial hyperlipemia (PPL) and hyperglycemia (PPG) are considered risk factors for coronary heart disease (CHD) and premature death; whereas physical exercise improves lipid profile and glucose tolerance thus decreasing cardiovascular risks.

OBJECTIVE

To investigate the effects of low-intensity fasted aerobic exercise on the magnitude of the PPL and PPG responses to meals with different energy content, in normal and obese subjects.

METHODS

The study used a randomized crossover design. Twenty-one male (Lean: n = 9, BMI: 24.3 ± 2.2; and obese: n = 12, BMI 32.31 ± 2.1) volunteers aged 20-30 years, performed three interventions, separated by 7 days each: (i) 45 min at rest and isocaloric high-fat meal (60% lipids, 30% carbohydrates and 10% protein); (ii) fasted low-intensity aerobic exercise (50% VO_2max) for 45 min followed by an isocaloric or (iii) calorie deficit high-fat meal. Subjects were serially assessed for blood triglycerides, and glucose levels.

RESULTS AND CONCLUSIONS

Low-intensity fasted aerobic exercise had no acute effect on PPL in lean and obese subjects. Glucose concentrations were reduced only in lean subjects. There is a significant difference in PPL values when comparing lean to obese subjects, implying that the nutritional status influences lipid and carbohydrate after fasted low-intensity aerobic exercise. Registered under ClinicalTrials.gov Identifier no. NCT00929890.

A New Equation for Calculation of Low-Density Lipoprotein Cholesterol in Patients With Normolipidemia and/or Hypertriglyceridemia

Importance

Low-density lipoprotein cholesterol (LDL-C), a key cardiovascular disease marker, is often estimated by the Friedewald or Martin equation, but calculating LDL-C is less accurate in patients with a low LDL-C level or hypertriglyceridemia (triglyceride [TG] levels ≥400 mg/dL).

Objective

To design a more accurate LDL-C equation for patients with a low LDL-C level and/or hypertriglyceridemia.

Design, Setting, and Participants

Data on LDL-C levels and other lipid measures from 8656 patients seen at the National Institutes of Health Clinical Center between January 1, 1976, and June 2, 1999, were analyzed by the β-quantification reference method (18 715 LDL-C test results) and were randomly divided into equally sized training and validation data sets. Using TG and non-high-density lipoprotein cholesterol as independent variables, multiple least squares regression was used to develop an equation for very low-density lipoprotein cholesterol, which was then used in a second equation for LDL-C. Equations were tested against the internal validation data set and multiple external data sets of either β-quantification LDL-C results (n = 28 891) or direct LDL-C test results (n = 252 888). Statistical analysis was performed from August 7, 2018, to July 18, 2019.

Main Outcomes and Measures

Concordance between calculated and measured LDL-C levels by β-quantification, as assessed by various measures of test accuracy (correlation coefficient [R2], root mean square error [RMSE], mean absolute difference [MAD]), and percentage of patients misclassified at LDL-C treatment thresholds of 70, 100, and 190 mg/dL.

Results

Compared with β-quantification, the new equation was more accurate than other LDL-C equations (slope, 0.964; RMSE = 15.2 mg/dL; R2 = 0.9648; vs Friedewald equation: slope, 1.056; RMSE = 32 mg/dL; R2 = 0.8808; vs Martin equation: slope, 0.945; RMSE = 25.7 mg/dL; R2 = 0.9022), particularly for patients with hypertriglyceridemia (MAD = 24.9 mg/dL; vs Friedewald equation: MAD = 56.4 mg/dL; vs Martin equation: MAD = 44.8 mg/dL). The new equation calculates the LDL-C level in patients with TG levels up to 800 mg/dL as accurately as the Friedewald equation does for TG levels less than 400 mg/dL and was associated with 35% fewer misclassifications when patients with hypertriglyceridemia (TG levels, 400-800 mg/dL) were categorized into different LDL-C treatment groups.

Conclusions and Relevance

The new equation can be readily implemented by clinical laboratories with no additional costs compared with the standard lipid panel. It will allow for more accurate calculation of LDL-C level in patients with low LDL-C levels and/or hypertriglyceridemia (TG levels, ≤800 mg/dL) and thus should improve the use of LDL-C level in cardiovascular disease risk management.

Triglyceride-Rich Lipoprotein Cholesterol, Small Dense LDL Cholesterol, and Incident Cardiovascular Disease

BACKGROUND

Elevated triglyceride-rich lipoprotein (TRL) and small-dense low-density lipoprotein (sdLDL) particles are hallmarks of atherogenic dyslipidemia, and their cholesterol content is hypothesized to drive atherosclerotic risk. Prospective epidemiological data pertaining to cholesterol content of TRLs and sdLDL in primary prevention populations are mostly limited to coronary heart disease.

OBJECTIVES

The purpose of this study was to prospectively evaluate whether triglyceride-rich lipoprotein cholesterol (TRL-C) and small-dense low-density lipoprotein cholesterol (sdLDL-C) concentrations associate with composite and individual incident cardiovascular disease (CVD) outcomes including myocardial infarction (MI), ischemic stroke (IS), and peripheral artery disease (PAD).

METHODS

In a prospective case-cohort study within the Women's Health Study, TRL-C and sdLDL-C (mg/dl) were directly measured in baseline blood specimens of case subjects (n = 480) and the reference subcohort (n = 496). Risk associations were evaluated for total CVD (MI, IS, PAD, and CVD death), coronary and cerebrovascular disease (MI, IS, CVD death), and individual outcomes (MI, IS, and PAD). Models were adjusted for traditional risk factors, low-density lipoprotein cholesterol, and high-sensitivity C-reactive protein.

RESULTS

The risk of both composite outcomes significantly increased across quartiles of TRL-C and sdLDL-C. TRL-C was significantly associated with MI and PAD (MI hazard ratio [HR]_Q4: 3.05 [95% confidence interval (CI): 1.46 to 6.39]; p_trend = 0.002; PAD HR_Q4: 2.58 [95% CI: 1.18 to 5.63]; p_trend = 0.019), whereas sdLDL-C was significantly associated with MI alone (HR_Q4: 3.71 [95% CI: 1.59 to 8.63]; p_trend < 0.001). Both markers weakly associated with IS. Association patterns were similar for continuous exposures and, for TRL-C, among subjects with low atherogenic particle concentrations (apolipoprotein B <100 mg/dl).

CONCLUSIONS

TRL-C strongly associates with future MI and PAD events, whereas sdLDL-C strongly associates with MI alone. These findings signal that the cholesterol content of TRLs and sdLDL influence atherogenesis independently of low-density lipoprotein cholesterol, and high sensitivity C-reactive protein, with potentially different potency across vascular beds. (Women's Health Study; NCT00000479).

Association between postprandial lipoprotein subclasses and Framingham cardiovascular disease risk stratification

OBJECTIVE

To determine the ability of postprandial lipoprotein subclass concentrations to stratify patients with respect to their risk for cardiovascular disease (CVD).

METHODS

Using the Framingham cardiovascular disease risk score (FRS) algorithm, a total of 112 consecutive patients referred for community health screening were stratified into two groups: (a) low-risk (FRS < 10%) and (b) intermediate/high-risk (FRS ≥ 10%). Serum lipoprotein subclass concentrations were determined by Vertical Auto Profile (VAP-II).

RESULTS

Fasting and postprandial levels of LDL4, HDL2, VLDL1 + 2, VLDL3, and RLP, as well as fasting levels of ApoB and postprandial levels of LDL3 and IDL1, were significantly different in the intermediate/high risk FRS group vs. the low-risk group (P < 0.05). Correlations between Framingham CVD risk and LDL3, LDL4, IDL1, VLDL1 + 2, VLDL3, RLP, and ApoB were positive while negative for HDL2 in both the fasting and postprandial states. Intermediate/high risk for CVD was shown to be significantly associated with both fasting and postprandial levels of VLDL1 + 2 and RLP, as well as with postprandial LDL4 and VLDL3, as determined using forward conditional logistic regression analysis. Postprandial levels of VLDL1 + 2 were better at identifying patients in the intermediate/high-risk FRS group than fasting levels, although the differences were not significant due to overlapping reference intervals. In addition, the association between RLP and VLDL subclasses relative to Framingham CVD risk increased significantly in the postprandial state (ΔR² = 0.023; ΔF = 7.178; ΔP = 0.025) but not in the fasting state.

CONCLUSIONS

The use of postprandial lipoprotein subclass concentrations is not inferior to the use of fasting levels in identifying intermediate/high-risk FRS individuals. In addition, changes in RLP and VLDL subclass concentrations in fasting vs. postprandial states may reveal lipid metabolic mechanisms associated with CVD.

A study on the correlation between remnant cholesterol and urinary albumin to creatinine ratio in Chinese community adults: A report from the REACTION study

BACKGROUND

The correlation between remnant cholesterol (RC) and urinary albumin to creatinine ratio (UACR) has not been illustrated. The present study aims to explore the correlation between RC levels and UACR in Chinese community adults.

METHODS

This study included 35 848 participants from a cohort study (REACTION). The UACR data were divided into three groups: UACR <10 mg/g, 10 ≤UACR<30 mg/g, and UACR ≥30 mg/g groups. RC was divided into two groups, according to the 75th percentile: <75% group and ≥75% group. Multiple logistic regression analysis was used to evaluate the correlation between RC and UACR.

RESULTS

The RC exhibited an adjusted odds ratio that was significant in models 1-5. Although all confounders were corrected in model 5, RC and UACR were still significantly correlated， and the correlation was more significant in females，when compared to males (odds ratio [OR]: 1.117, 95% CI: 1.063-1.176, P < 0.001 for all subjects; OR: 1.092, 95% CI: 1.128-1.161, P = 0.004 for females; and OR: 1.085, 95% CI: 0.998-1.194, P = 0.088 for males). The RC was significantly correlated with UACR for subjects with 5.6 ≤ fasting blood glucose < 7.0 or 7.8 ≤ post-load blood glucose < 11.1 mmol/L, 24 ≤ body mass index (BMI) < 28 kg/m² , 120 ≤ systolic blood pressure < 140 and/or 80 ≤ diastolic blood pressure < 90 mm Hg.

CONCLUSIONS

In the Chinese community, RC is highly correlated with UACR, and the correlation is more significant in females compared with males. At higher RC levels, patients with critical values of blood pressure, BMI and blood glucose have a more significant correlation between RC and UACR.

[Diagnosis of atherogenic dyslipidaemia by primary care physicians in Spain]

OBJECTIVE

To describe the diagnostic management of patients with atherogenic dyslipidaemia (AD) by primary care physicians (PC).

METHODOLOGY

An observational, descriptive, cross-sectional study was conducted based on a structured questionnaire. The content of the questionnaire was based on a review of the literature, and was validated by 3 AD experts. It included 23 questions, and was addressed to primary care physicians (PC). This sub-study will analyse questions related to the detection and diagnosis of AD.

RESULTS

A total of 1,029 PC participated in the study. Almost all (96.99%) said that DA is a determining factor for cardiovascular risk (CVR), even with LDL-C targets. Residual CVR was evaluated by 88.43% in their clinical practice, but only 27.89% in secondary prevention. Most of the PCs used LDL-c-non-HDL-c (55.49% vs 20.02%) in AD as a control objective, and 15.35% used TG, and 9.14% HDL-C. For the diagnosis of AD, 82.22% used TC, TG, HDL-C, and non-HDL-C. PC physicians used the TC / HDL-C atherogenic ratio (53.06%) and LDL-C / HDL-C ratio (49.56%), considering them useful / very useful (86.30% and 85.04%, respectively), with only 28.08% using the TG / HDL-C index, with 69.29% considering it useful / very useful.

CONCLUSIONS

The PCs have a high level of knowledge of the guidelines. Underdiagnosis continues, with heterogeneity in determining objectives, and low use of the TG / HDL-C index to evaluate these patients. Greater awareness is needed for the detection and diagnosis of AD.

Remnant cholesterol as a risk factor for cardiovascular, cancer or other causes mortality: A competing risks analysis

BACKGROUND AND AIMS

Cardiovascular diseases (CVDis) are leading causes of morbidity and mortality. Even after the introduction of pharmacological therapy to lower Cholesterol, there is still a residual risk that may be ascribed to remnant cholesterol (RC). We aimed, by analyzing two prospective cohort studies, to estimate the effect of RC on risk and hazard of cardiovascular deaths (CVDs), while accounting for competing risks such as cancer (CDs) and other-causes deaths (OCDs).

METHODS AND RESULTS

Cohorts were enrolled in 1992 and 2005. Personal data history was recorded. A fasting venous blood sample was obtained, and RC was calculated at baseline. Cause of Death was coded by using ICD-10th version. Follow-up ended on December 31, 2017. Flexible parametric competing-risks models were applied, with age at death as time-axis. In total, 5729 subjects were enrolled. There were 861 (15.1%) deaths: 234 CVDs (27.2%), 245 CDs (28.5%), 271 OCDs (31.5%) and 111 unknown causes of death (12.8%). RC exposure was a strong risk factor only for CVDs (Risk 2.54, 95% Confidence Interval 1.21; 5.34; Trend 1.26 (1.00; 1.58) for ≥1.29 mmol/L).

CONCLUSIONS

RC is a strong independent risk factor for cardiovascular mortality. Competing risk analysis is demonstrably a useful tool to disentangle associations among different competing events with a common risk factor.

Estimated ASCVD risk according to statin use in US adults with borderline triglycerides: Results from National Health and Nutrition Examination Survey (NHANES) 2007-2014

Background

Elevated triglycerides (TGs) are associated with atherosclerotic cardiovascular disease (ASCVD). Despite statin therapy, many US adults have borderline or elevated TG levels. Not characterized is the ASCVD risk associated with borderline TG levels in statin users, including the estimated number of adults who will sustain ASCVD events.

Methods

We studied 4986 US adults (weighted to 113 million) aged 40–74 from the National Health and Nutrition Examination Surveys 2007–2014. The proportion of persons at low (<5%), borderline (5-<7.5%), intermediate (7.5-<20%), and high (≥20%) 10-year ASCVD risk among those on statins was quantified for low (<70 ​mg/dL, 70-<100 ​mg/dL), borderline (100-<135 ​mg/dL and 135-<150 ​mg/dL), borderline high (150-<200 ​mg/dL), and elevated (≥200 ​mg/dL) TGs. Multiple logistic regression examined these TG categories in relation to high risk status.

Results

Overall, 18.6% of participants had TG ​< ​70 ​mg/dL, 24.2% TG 70-<100 ​mg/dL, 22.0% TG 100-<135 ​mg/dL, 6.2% TG 135-<150 ​mg/dL, 15.0% TG 150-<200 ​mg/dL, and 14.0% TG ​≥ ​200 ​mg/dL. Mean 10-year ASCVD risk for these groups were 5.6%, 6.9%, 7.8%, 10.3%, 9.6% and 10.8%, respectively (p ​< ​0.0001). One-fifth or more of statin users with TGs over 135 ​mg/dL were at ≥ 20% 10-year ASCVD risk and ≥60% of persons in all TG groups were at borderline or higher ASCVD risk. Compared to those with TGs <70 ​mg/dL, multiple logistic regression showed odds ratios of 3.1 to 4.6 (p ​< ​0.05 to p ​< ​0.01) for those in TG groups ≥135 ​mg/dL in the overall sample, but 3.4 to 8.1 (p ​< ​0.05 to p < 0.01) for those in TG groups of ≥100 ​mg/dL in statin users, despite adjustment including HDL-C.

Conclusion

Many US adults with borderline levels of TGs are at elevated ASCVD risk despite statin therapy, suggesting the need first for greater lifestyle modification efforts, and when indicated, evidence-based therapies known to reduce this residual ASCVD risk.

Prognostic utility of triglyceride-rich lipoprotein-related markers in patients with coronary artery disease

TG-rich lipoprotein (TRL)-related biomarkers, including TRL-cholesterol (TRL-C), remnant-like lipoprotein particle-cholesterol (RLP-C), and apoC-III have been associated with atherosclerosis. However, their prognostic values have not been fully determined, especially in patients with previous CAD. This study aimed to examine the associations of TRL-C, RLP-C, and apoC-III with incident cardiovascular events (CVEs) in the setting of secondary prevention of CAD. Plasma TRL-C, RLP-C, and total apoC-III were directly measured. A total of 4,355 participants with angiographically confirmed CAD were followed up for the occurrence of CVEs. During a median follow-up period of 5.1 years (interquartile range: 3.9-6.4 years), 543 (12.5%) events occurred. Patients with incident CVEs had significantly higher levels of TRL-C, RLP-C, and apoC-III than those without events. Multivariable Cox analysis indicated that a log unit increase in TRL-C, RLP-C, and apoC-III increased the risk of CVEs by 49% (95% CI: 1.16-1.93), 21% (95% CI: 1.09-1.35), and 40% (95% CI: 1.11-1.77), respectively. High TRL-C, RLP-C, and apoC-III were also independent predictors of CVEs in individuals with LDL-C levels ≤1.8 mmol/l (n = 1,068). The addition of RLP-C level to a prediction model resulted in a significant increase in discrimination, and all three TRL biomarkers improved risk reclassification. Thus, TRL-C, RLP-C, and apoC-III levels were independently associated with incident CVEs in Chinese CAD patients undergoing statin therapy.

The longitudinal association of remnant cholesterol with cardiovascular outcomes in patients with diabetes and pre-diabetes

Background

The atherogenicity of remnant cholesterol (RC) has been underlined by recent guidelines, which was linked to coronary artery disease (CAD), especially for patients with diabetes mellitus (DM). This study aimed to examine the prognostic value of plasma RC in the patients with CAD under different glucose metabolism status.

Methods

Fasting plasma RC were directly calculated or measured in 4331 patients with CAD. Patients were followed for the occurrence of major adverse cardiovascular events (MACEs) and categorized according to both glucose metabolism status [DM, pre-DM, normoglycemia (NG)] and RC levels. Cox proportional hazards model was used to calculate hazard ratios (HRs) with 95% confidence intervals.

Results

During a mean follow-up of 5.1 years, 541 (12.5%) MACEs occurred. The risk for MACEs was significantly higher in patients with elevated RC levels after adjustment for potential confounders. No significant difference in MACEs was observed between pre-DM and NG groups (p > 0.05). When stratified by combined status of glucose metabolism and RC, highest levels of calculated and measured RC were significant and independent predictors of developing MACEs in pre-DM (HR: 1.64 and 1.98; both p < 0.05) and DM (HR: 1.62 and 2.05; both p < 0.05). High RC levels were also positively associated with MACEs in patients with uncontrolled DM. .

Conclusions

In this large-scale and long-term follow-up cohort study, data firstly demonstrated that higher RC levels were significantly associated with the worse prognosis in DM and pre-DM patients with CAD, suggesting that RC may be a target for patients with impaired glucose metabolism.

Importance of lipid ratios for predicting intracranial atherosclerotic stenosis

BACKGROUND

This study aims to investigate the association of lipid ratios with intracranial atherosclerotic stenosis (ICAS) in a Chinese population.

METHODS

This cross-sectional study included 658 consecutive patients with ischemic stroke. Intracranial and extracranial arteries were evaluated for atherosclerotic stenosis using digital subtraction angiography or computed tomography angiography. Lipid ratios [total cholesterol (TC)/high-density lipoprotein-cholesterol (HDL-C), triglycerides (TG)/HDL-C, low-density lipoprotein-cholesterol (LDL-C)/HDL-C, non-high-density lipoprotein-cholesterol (non-HDL-C)/HDL-C, remnant cholesterol (RC)/HDL-C, apolipoprotein B (apo B)/apolipoprotein A-I (apo A-I), and apo B/HDL-C] were calculated.

RESULTS

The TC/HDL-C, LDL-C/HDL-C, RC/HDL-C, non-HDL-C/HDL-C, apo B/HDL-C and apo B/apo A-I ratios (all P < 0.05) were significantly associated with ICAS but not with extracranial atherosclerotic stenosis after adjustment for confounding factors. Receiver operating characteristic (ROC) curves analysis revealed that the apo B/apo A-I ratio had the largest area under the ROC curve (AUC) among lipid levels alone and for lipid ratios (AUC = 0.588). Lipid ratios had higher AUC values than those for lipid levels alone for the identification of ICAS.

CONCLUSION

The TC/HDL-C, LDL-C/HDL-C, RC/HDL-C, non-HDL-C/HDL-C apo B/HDL-C, and apo B/apo A-I ratios were significantly related to ICAS risk. Compared with the other variables tested, the apo B/apo A-I ratio appeared to be a better discriminator for identifying ICAS risk in stroke patients.

Profound reductions in first and total cardiovascular events with icosapent ethyl in the REDUCE-IT trial: why these results usher in a new era in dyslipidaemia therapeutics

The aims of this clinical review are to: (i) highlight the importance of elevated baseline triglycerides (TG) in the setting of well-controlled low-density lipoprotein cholesterol (LDL-C) on statins as a major contributor to residual atherosclerotic cardiovascular disease (ASCVD) risk, particularly among patients with type 2 diabetes mellitus, metabolic syndrome, and obesity whose distinctive lipid phenotype cannot be optimally treated with LDL-C reduction therapy alone; (ii) describe the findings and clinical implications of the landmark REDUCE-IT trial in which ethyl eicosapentaenoic acid significantly improved ASCVD outcomes. While many genetic studies have shown that elevated TG are an independent causal factor for ASCVD, prior placebo-controlled trials using niacin, fibrates, omega-3 fatty acids, and dietary supplement fish oil preparations have failed to demonstrate significant CV event reduction when added to statin therapy. In contrast, the REDUCE-IT trial in 8179 participants showed convincingly that the administration of 4 g daily of icosapent ethyl (an ethyl ester of eicosapentaenoic acid) in patients at high risk for ASCVD with increased levels of baseline TG [median value, 2.44 mmol/L (216.0 mg/dL)] but well-controlled LDL-C [median value, 1.94 mmol/L (75.0 mg/dL)] reduced significantly incident events across both the trial primary endpoint and multiple prespecified secondary endpoints, including cardiovascular death, as well as both subsequent and total primary endpoint and key secondary endpoint events. Icosapent ethyl unequivocally contributed to ASCVD event reduction over and above statin therapy. The REDUCE-IT trial results should alter our approach to managing a growing population of hypertriglyceridaemic patients whose lipid phenotype requires more intensive treatment beyond LDL-C lowering alone.

Remnant lipoproteins: are they equal to or more atherogenic than LDL?

PURPOSE OF REVIEW

To critically appraise new insights into the biology of remnant lipoproteins and their putative role in the pathophysiology of atherosclerotic cardiovascular disease, and to compare the atherogenicity of remnant particles with that of low-density lipoproteins (LDL).

RECENT FINDINGS

New in-vivo stable isotope tracer studies of the kinetics of apoB48 and apoB100-containing lipoproteins in postprandial conditions have revealed that apoB48-containing very low-density lipoproteins (VLDL) accumulated markedly in hypertriglyceridemic patients. These intestinally-derived particles were cleared slowly, and represented up to 25% of circulating VLDL; as part of the remnant particle population, they may increase cardiovascular risk. Importantly, the PCSK9 inhibitor, evolocumab, was shown to reduce remnant levels (-29%) during the postprandial period in diabetic patients on statin therapy - an effect which may be additive to that of LDL-cholesterol reduction in conferring cardiovascular benefit. In recent Mendelian randomization studies, the effect of lowering triglyceride-rich lipoproteins or LDL-cholesterol translated to similar clinical benefit per unit of apoB. Finally, in randomized trials involving statin-treated patients with atherosclerotic cardiovascular disease, remnant cholesterol levels were associated with coronary atheroma progression independently of LDL-cholesterol.

SUMMARY

Overall, data from observational studies in large cohorts, Mendelian randomization studies, meta-regression analyses, and post-hoc analyses of randomized trials are consistent with the contention that remnants are highly atherogenic particles and contribute to the atherosclerotic burden in an equivalent manner to that of LDL.

Hypolipidemic and antioxidant activities of Trichosanthes kirilowii maxim seed oil and flavonoids in mice fed with a high-fat diet

Trichosanlhes kirilowii Maxim seed oil (TSO) is rich in conjugated linolenic acids, and the flavonoids (FLA) combined with n-3 fatty acids can effectively change the plasma antioxidant capacity. Hyperlipidemia and oxidative stress are one of the most important risk factors for cardiovascular disease. This study aims to evaluate the effect of the TSO, FLA, and TSO combined with FLA (TSOFLA) intake on hyperlipemia mice. TSO and TSOFLA administration resulted in a significant decline in serum levels of total cholesterol, triglycerides, and low density lipoprotein-cholesterol. TSOFLA improved the hepatic and serum antioxidant status as assessed by superoxide dismutase, glutathione peroxidase activities, and reduced the levels of lipid peroxidation. Hematoxylin-eosin staining of liver and aorta tissue has shown a marked reduction of the hyperlipidemia-induced lesions by gavage TSOFLA. Compared with TSO and FLA, TSOFLA has more significant hypolipidemic and antioxidant activities, which effects may be correlated to the synergy between TSO and FLA. PRACTICAL APPLICATIONS: Dyslipidemia is a common metabolic disorder, which is characterized by triglyceride levels increased, total cholesterol, and low-density lipoprotein cholesterol. Lipid-lowering treatment can reduce the expansion of coronary atherosclerosis, and particular the dietary lipids have important roles in controlling the concentrations of these risk factors. This is the first study evaluating the hypolipidemic and antioxidant activities effects of Trichosanlhes kirilowii Maxim seed oil (TSO), flavonoids (FLA), and TSO combined with FLA (TSOFLA) intake on hyperlipemia mice caused by a high-fat diet. The pharmacological effects of dietary TSOFLA are correlated to its high content of unsaturated fatty acids and flavonoids. This information can be of interest to the development of food supplements in the field of diseases associated with high-fat intakes such as cardiovascular diseases and adiposis.

Postprandial Hypertriglyceridaemia Revisited in the Era of Non-Fasting Lipid Profile Testing: A 2019 Expert Panel Statement, Main Text

Residual vascular risk exists despite the aggressive lowering of Low-Density Lipoprotein Cholesterol (LDL-C). A contributor to this residual risk may be elevated fasting, or non-fasting, levels of Triglyceride (TG)-rich lipoproteins. Therefore, there is a need to establish whethe a standardised Oral Fat Tolerance Test (OFTT) can improve atherosclerotic Cardiovascular (CV) Disease (ASCVD) risk prediction in addition to a fasting or non-fasting lipid profile. An expert panel considered the role of postprandial hypertriglyceridaemia (as represented by an OFTT) in predicting ASCVD. The panel updated its 2011 statement by considering new studies and various patient categories. The recommendations are based on expert opinion since no strict endpoint trials have been performed. Individuals with fasting TG concentration <1 mmol/L (89 mg/dL) commonly do not have an abnormal response to an OFTT. In contrast, those with fasting TG concentration ≥2 mmol/L (175 mg/dL) or nonfasting ≥2.3 mmol/L (200 mg/dL) will usually have an abnormal response. We recommend considering postprandial hypertriglyceridaemia testing when fasting TG concentrations and non-fasting TG concentrations are 1-2 mmol/L (89-175 mg/dL) and 1.3-2.3 mmol/L (115-200 mg/dL), respectively as an additional investigation for metabolic risk prediction along with other risk factors (obesity, current tobacco abuse, metabolic syndrome, hypertension, and diabetes mellitus). The panel proposes that an abnormal TG response to an OFTT (consisting of 75 g fat, 25 g carbohydrate and 10 g proteins) is >2.5 mmol/L (220 mg/dL). Postprandial hypertriglyceridaemia is an emerging factor that may contribute to residual CV risk. This possibility requires further research. A standardised OFTT will allow comparisons between investigational studies. We acknowledge that the OFTT will be mainly used for research to further clarify the role of TG in relation to CV risk. For routine practice, there is a considerable support for the use of a single non-fasting sample.

Postprandial hyperlipidemia as a risk factor in patients with type 2 diabetes

Introduction: Postprandial hyperlipidemia is a common feature of the atherogenic dyslipidemia in patients with type 2 diabetes. Quantification of this with oral fat tolerance tests is not used routinely in clinical practice and abnormal postprandial lipids are usually inferred from non-fasting plasma triglyceride levels. Identifying excessive postprandial hyperlipidemia may help to refine cardiovascular risk assessment but there are no treatments currently available which selectively target postprandial lipids and no large cardiovascular outcome trials using this as the entry criterion.Areas covered: In this review of relevant published material, we summarize the findings from the most important publications in this area.Expert opinion: Postprandial hyperlipidemia appears to contribute to the cardiovascular risk in patients with diabetes. Non-fasting triglyceride levels provide a surrogate marker of postprandial hyperlipidemia but more specific markers such as apoB48 levels may prove to be more reliable. Omega-3 fatty acids, fibrates and ezetimibe can reduce postprandial lipids but may not correct them completely. Several novel treatments have been developed to target hypertriglyceridemia and some of these may be particularly effective in improving postprandial levels. Further clinical trials are needed to establish the role of postprandial lipids in assessment of cardiovascular risk and to identify the most effective treatments.

Low LDL Cholesterol by PCSK9 Variation Reduces Cardiovascular Mortality

BACKGROUND

Reduced low-density lipoprotein (LDL) cholesterol due to inhibition of proprotein convertase subtilisin/kexin 9 (PCSK9) reduces cardiovascular events and may therefore also reduce cardiovascular and all-cause mortality.

OBJECTIVES

This study tested the hypothesis that genetically low LDL cholesterol due to PCSK9 variation is causally associated with low cardiovascular and all-cause mortality in the general population.

METHODS

A total of 109,566 individuals from the Copenhagen General Population Study and the Copenhagen City Heart Study were genotyped for PCSK9 R46L (rs11591147), R237W (rs148195424), I474V (rs562556), and E670G (rs505151). During a median follow-up of 10 years (range 0 to 42 years) and 1,247,225 person-years, there were 3,828 cardiovascular deaths and 16,373 deaths from any cause. Results were validated using data on 431,043 individuals from the UK Biobank.

RESULTS

An increasing number of weighted PCSK9 alleles were associated with stepwise lower LDL cholesterol of up to 0.61 mmol/l (24 mg/dl; 18.2%; p for trend <0.001) and with lower cardiovascular mortality (p = 0.001), but not with lower all-cause mortality (p = 0.11). In causal, genetic analyses, a 0.5-mmol/l (19.4-mg/dl) lower LDL cholesterol was associated with risk ratios for cardiovascular and all-cause mortality of 0.79 (95% confidence interval [CI]: 0.63 to 0.99; p = 0.04) and 1.02 (95% CI: 0.94 to 1.12; p = 0.63) in the Copenhagen studies, 0.79 (95% CI: 0.58 to 1.08; p = 0.14) and 0.98 (95% CI: 0.87 to 1.10; p = 0.75) in the UK Biobank, and of 0.79 (95% CI: 0.65 to 0.95; p = 0.01) and 1.01 (95% CI: 0.94 to 1.08; p = 0.85), respectively, in studies combined.

CONCLUSIONS

Genetically low LDL cholesterol due to PCSK9 variation was causally associated with low risk of cardiovascular mortality, but not with low all-cause mortality in the general population.

Apolipoprotein A-IV Enhances Fatty Acid Uptake by Adipose Tissues of Male Mice via Sympathetic Activation

Apolipoprotein A-IV (ApoA-IV) synthesized by the gut regulates lipid metabolism. Sympathetic innervation of adipose tissues also controls lipid metabolism. We hypothesized that ApoA-IV required sympathetic innervation to increase fatty acid (FA) uptake by adipose tissues and brown adipose tissue (BAT) thermogenesis. After 3 weeks feeding of either a standard chow diet or a high-fat diet (HFD), mice with unilateral denervation of adipose tissues received intraperitoneal administration of recombinant ApoA-IV protein and intravenous infusion of lipid mixture with radioactive triolein. In chow-fed mice, ApoA-IV administration increased FA uptake by intact BAT but not the contralateral denervated BAT or intact white adipose tissue (WAT). Immunoblots showed that, in chow-fed mice, ApoA-IV increased expression of lipoprotein lipase and tyrosine hydroxylase in both intact BAT and inguinal WAT (IWAT), while ApoA-IV enhanced protein levels of β3 adrenergic receptor, adipose triglyceride lipase, and uncoupling protein 1 in the intact BAT only. In HFD-fed mice, ApoA-IV elevated FA uptake by intact epididymal WAT (EWAT) but not intact BAT or IWAT. ApoA-IV increased sympathetic activity assessed by norepinephrine turnover (NETO) rate in BAT and EWAT of chow-fed mice, whereas it elevated NETO only in EWAT of HFD-fed mice. These observations suggest that, in chow-fed mice, ApoA-IV activates sympathetic activity of BAT and increases FA uptake by BAT via innervation, while in HFD-fed mice, ApoA-IV stimulates sympathetic activity of EWAT to shunt FAs into the EWAT.

The influence of rare variants in circulating metabolic biomarkers

Circulating metabolite levels are biomarkers for cardiovascular disease (CVD). Here we studied, association of rare variants and 226 serum lipoproteins, lipids and amino acids in 7,142 (discovery plus follow-up) healthy participants. We leveraged the information from multiple metabolite measurements on the same participants to improve discovery in rare variant association analyses for gene-based and gene-set tests by incorporating correlated metabolites as covariates in the validation stage. Gene-based analysis corrected for the effective number of tests performed, confirmed established associations at APOB, APOC3, PAH, HAL and PCSK (p<1.32x10-7) and identified novel gene-trait associations at a lower stringency threshold with ACSL1, MYCN, FBXO36 and B4GALNT3 (p<2.5x10-6). Regulation of the pyruvate dehydrogenase (PDH) complex was associated for the first time, in gene-set analyses also corrected for effective number of tests, with IDL and LDL parameters, as well as circulating cholesterol (pMETASKAT<2.41x10-6). In conclusion, using an approach that leverages metabolite measurements obtained in the same participants, we identified novel loci and pathways involved in the regulation of these important metabolic biomarkers. As large-scale biobanks continue to amass sequencing and phenotypic information, analytical approaches such as ours will be useful to fully exploit the copious amounts of biological data generated in these efforts.

Triglycerides, HDL cholesterol and atherogenic dyslipidaemia in the 2019 European guidelines for the management of dyslipidaemias

In general, both European and American clinical guidelines have addressed the management of atherogenic dyslipidaemia in an unconvincing and even superficial way, largely because of the available therapeutic limitations. Consequently, this type of dyslipidaemia is underdiagnosed, under-treated, and under-controlled. Given the recent presentation of the 2019 guidelines of the European Atherosclerosis Society and the European Society of Cardiology on the management of dyslipidaemias, it seems appropriate to examine its position with respect to atherogenic dyslipidaemia and/or its main components, the increase in triglyceride-rich lipoproteins, and the decrease of high-density lipoprotein cholesterol.

Fatty acid regio-specificity of triacylglycerol molecules may affect plasma lipid responses to dietary fats-a randomised controlled cross-over trial

BACKGROUND/OBJECTIVES

Hypercholesterolaemic effects of saturated fatty acids (SFA) may be influenced not only by the chain length, but also by their specific location within the triacylglycerol (TAG) molecule. We examined the hypothesis that dietary fats rich in SFA, but containing mostly unsaturated fatty acids in the sn-2 position with most SFA in sn-1 and -3 (palm olein [PO] and cocoa butter [CB]) will have similar serum lipid outcomes to unsaturated olive oil (OO).

SUBJECTS/METHODS

Thirty-eight participants (20-40 yr, 18.5- ≤ 27.5 kg/m2) completed a 4-week randomised 3 × 3 crossover feeding intervention, preceded by 2-week run-in and separated by 2-week washout periods. Background diet contained 35 percentage of total energy (%E) fat, 18%E protein, 48%E carbohydrates, differing in test fats only (palm olein (PO), CB, OO; 20%E). Total cholesterol (TC)/high density lipoprotein cholesterol (HDL-C) ratio and related variables; TC, HDL-C, low density lipoprotein cholesterol (LDL-C), TAG, apoA1, ApoB, ApoA1 (apolipoprotein A1)/ApoB (apolipoprotein B), lipoprotein (a) (Lp(a)), NEFA, LDL sub-fractions, were assessed pre- and post-intervention. Data were analysed using mixed effects longitudinal models with a P-value < 0.05 considered significant.

RESULTS

Changes in plasma fatty acids (P < 0.05) confirmed compliance; C18:1 increased with OO compared to PO and CB; C16:0 decreased with OO and C18:0 increased following CB. No differences were seen for TC/HDL-C (mean [95%CI] change for PO, 0.08[0.00, 0.15] mmol/L; CB, 0.06 [-0.05, 0.16] mmol/L; and OO, -0.01 [-0.15, 0.13] mmol/L; P = 0.53] or any other parameter including LDL sub-fractions. OO decreased IDL-A compared to PO (-2.2 [-4.31, -0.21] mg/dL, P = 0.03).

CONCLUSION

In healthy young participants, plasma lipid responses to PO and CB, enriched in SFA but having primarily unsaturated fatty acid in the sn-2 position of TAG, did not differ from OO.

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.

Potentially modifiable blood triglyceride levels by the control of conventional risk factors

Backgrounds

Triglyceride (TG) is known to be regulated by multiple lifestyle factors rather than genetic factors. This cross-sectional and community-based study (Healthy Twin study in Korea) aimed to estimate the “modifiable TG level” by identifying non-genetic risk factors of TG.

Methods

Participants were recruited between 2006 and 2011 who fulfilled health examinations and detail surveys: 3079 Korean adults including 949 monozygotic twins and 222 dizygotic twins. In order to investigate conventional risk factors, a mixed model accounting for family as a random effect was performed. In addition, we conducted a co-twin control analysis for 452 monozygotic twin (MZ) pairs, to examine non-genetic risk factors and potentially modifiable serum triglyceride levels.

Results

After excluding patients on dyslipidemia or diabetes medication, 2672 individuals (1029 men, with mean age of 43.9; and 1643 women with mean age of 43.3; 949 MZ pairs, 222 dizygotic twin pairs, and 1501sibling pairs) were analyzed. Fasting blood sugar (FBS), lipid panel, height, weight, waist (WC) and hip circumference, body mass index (BMI), amount of dietary intake and amount of physical activity was examined after adjusting for age and sex. For conventional analysis, WC, fat %, and BMI were identified as significant factors influencing serum triglyceride levels. Examination of non-genetic factors from the Co-twin control study revealed BMI (beta coefficient 9.94 with C.I. 3.42 to 16.46) and amount of alcohol intake (beta coefficient 0.08 with C.I. 0.02 to 0.14) as significant factors.

Conclusion

Our findings suggest that controlling body weight and alcohol intake might be effective to control TG; moderate weight control (BMI 1 reduction) and reducing alcohol consumption by 50 g/week (about two glassed of beer) might reduce TG level by 9.94 and 4.0 mg/dL.

Comparing remnant lipoprotein cholesterol measurement methods to evaluate efficacy of ezetimibe/statin vs statin therapy

BACKGROUND

Elevated remnant lipoprotein cholesterol (RLP-C) levels increase cardiovascular disease risk. However, RLP-C measurement methods are not standardized, leading to variations across studies.

OBJECTIVE

To evaluate the effect of ezetimibe (Eze) + statins vs statin monotherapy on RLP-C using immunoseparation (IM), vertical auto profile (VAP) ultracentrifugation, and calculated RLP-C measurement methods.

METHODS

This post hoc analysis evaluated data pooled from 3 first-line (all-statin [simvastatin 10/20/40/80 mg] vs Eze + statin [Eze 10 mg + simvastatin]) and 2 second-line (statin [atorvastatin uptitrated to 40/80 mg] vs statin + Eze [atorvastatin 20/40 mg + Eze 10 mg]) studies. Similarity of RLP-C methods was evaluated using Pearson correlation coefficients and Bland-Altman plots. RLP-C changes and percent changes from baseline were measured by all 3 methods in first-line and VAP and calculated methods in second-line studies.

RESULTS

Correlations between methods were generally moderate to strong for RLP-C levels, changes, and percent changes across treatment groups (r = 0.29-0.79) but with little evidence of agreement by Bland-Altman plots. Baseline RLP-C levels for Eze + statin vs all-statin groups were lower by IM (14.0 vs 14.0) compared with VAP (36.9 vs 35.9) and calculated (32.8 vs 33.3) methods. RLP-C changes (mg/dL) and percent changes from baseline were significantly greater (P < .01) with Eze + statins vs statins by VAP, calculated, and IM methods (between-treatment differences: -5.0 and -12.0, -2.0 and -5.4, and -1.5 and -12.1, respectively) in first-line, and VAP and calculated methods (between-treatment differences: -5.0 and -19.9 and -2.0 and -7.3) in second-line studies.

CONCLUSION

Although the 3 methods showed little agreement, each supported Eze + statins for achieving greater RLP-C reductions vs statin monotherapy; variability of results reinforces urgent need to standardize RLP-C measurements.

Postpartum metabolic syndrome after gestational hypertension and preeclampsia, a prospective cohort study

OBJECTIVE

We evaluated the 6-month postpartum risk of metabolic syndrome (MetS), a marker of future cardiovascular disease (CVD) risk, comparing women whose most recent pregnancies were complicated with gestational hypertension (GH) or preeclampsia (PE) versus those who had normotensive pregnancies.

STUDY DESIGN

This was a prospective cohort study in which women with GH or PE and normotensive women were actively enrolled during the first 12 weeks after delivery in Nairobi, Kenya. Participants were interviewed, blood pressures and anthropometric measurements including waist circumference obtained at enrollment and 6 months postpartum. Fasting lipid profile and plasma glucose were measured at 6 months postpartum. A generalized linear regression model with Poisson distribution was used to estimate crude relative risk (RR) of 6-month postpartum MetS and adjusted RR (ARR) after adjusting for apriori potential confounders.

RESULTS

Among 194 postpartum women, 63 (32%) had experienced GH or PE. Prevalence of MetS at 6 months postpartum was higher among women whose pregnancies were complicated with GH or PE (34.9%) compared to those who were normotensive (11.5%). GH and PE were associated with a 3-fold or greater risk of MetS (ARR) 3.01; 95% Confidence interval [CI] 1.58, 5.71; p < 0.001) overall and three of the five components, namely hypertension (ARR 3.35 [2.04, 5.51], p < 0.001), hypertriglyceridemia (ARR 3.25 [1.16-9.10], p = 0.01), and fasting hyperglycemia (ARR 6.20 [1.07-35.76], p = 0.03), compared to having normal blood pressures during pregnancy.

CONCLUSION

At 6  months postpartum, GH and PE were associated with three-fold or higher risk of MetS and especially hypertension, fasting hypertriglyceridemia, and fasting hyperglycemia.

Is maternal lipid profile in early pregnancy associated with pregnancy complications and blood pressure in pregnancy and long term postpartum?

BACKGROUND

An atherogenic lipid profile is a risk factor for the initiation and progression of atherosclerosis. This ultimately leads to cardiovascular disease. Women with a history of hypertensive disorders of pregnancy are at increased risk of sustained hypertension and cardiovascular disease later in life. Currently it is unclear whether dyslipidemia during pregnancy contributes to these risks.

OBJECTIVE

The objective of the study was to determine the associations between early pregnancy maternal lipid profile, hypertensive disorders of pregnancy, and blood pressure during and years after pregnancy.

STUDY DESIGN

We included 5690 women from the Generation R Study, an ongoing population-based prospective birth cohort. Two hundred eighteen women (3.8%) developed gestational hypertension and 139 (2.4%) preeclampsia. A maternal lipid profile consisting of total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, remnant cholesterol, and non-high-density lipoprotein cholesterol was determined in early pregnancy (median, 13.4 weeks of gestation). Systolic and diastolic blood pressures were measured in early, mid-, and late pregnancy and 6 and 9 years after pregnancy.

RESULTS

Triglycerides and remnant cholesterol in early pregnancy were positively associated with preeclampsia. Maternal lipid levels in early pregnancy were not associated with gestational hypertension. Total cholesterol, low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, and especially triglycerides and remnant cholesterol were positively associated with blood pressure in pregnancy and 6 and 9 years after pregnancy. Triglycerides and remnant cholesterol are positively associated with sustained hypertension 6 and 9 years after pregnancy.

CONCLUSION

An atherogenic lipid profile in early pregnancy reflecting impaired triglyceride-rich lipoprotein metabolism is independently associated with preeclampsia and blood pressure throughout pregnancy but also with sustained hypertension long term postpartum. Lipid levels in early pregnancy may help to identify women at risk for future hypertension and perhaps also women at risk for future cardiovascular disease.

From genome-wide association studies to Mendelian randomization: novel opportunities for understanding cardiovascular disease causality, pathogenesis, prevention, and treatment

The Mendelian randomization approach is an epidemiological study design incorporating genetic information into traditional epidemiological studies to infer causality of biomarkers, risk factors, or lifestyle factors on disease risk. Mendelian randomization studies often draw on novel information generated in genome-wide association studies on causal associations between genetic variants and a risk factor or lifestyle factor. Such information can then be used in a largely unconfounded study design free of reverse causation to understand if and how risk factors and lifestyle factors cause cardiovascular disease. If causation is demonstrated, an opportunity for prevention of disease is identified; importantly however, before prevention or treatment can be implemented, randomized intervention trials altering risk factor levels or improving deleterious lifestyle factors needs to document reductions in cardiovascular disease in a safe and side-effect sparse manner. Documentation of causality can also inform on potential drug targets, more likely to be successful than prior approaches often relying on animal or cell studies mainly. The present review summarizes the history and background of Mendelian randomization, the study design, assumptions for using the design, and the most common caveats, followed by a discussion on advantages and disadvantages of different types of Mendelian randomization studies using one or more samples and different levels of information on study participants. The review also provides an overview of results on many of the risk factors and lifestyle factors for cardiovascular disease examined to date using the Mendelian randomization study design.

The selective peroxisome proliferator-activated receptor alpha modulator (SPPARMα) paradigm: conceptual framework and therapeutic potential : A consensus statement from the International Atherosclerosis Society (IAS) and the Residual Risk Reduction Initiative (R3i) Foundation

In the era of precision medicine, treatments that target specific modifiable characteristics of high-risk patients have the potential to lower further the residual risk of atherosclerotic cardiovascular events. Correction of atherogenic dyslipidemia, however, remains a major unmet clinical need. Elevated plasma triglycerides, with or without low levels of high-density lipoprotein cholesterol (HDL-C), offer a key modifiable component of this common dyslipidemia, especially in insulin resistant conditions such as type 2 diabetes mellitus. The development of selective peroxisome proliferator-activated receptor alpha modulators (SPPARMα) offers an approach to address this treatment gap. This Joint Consensus Panel appraised evidence for the first SPPARMα agonist and concluded that this agent represents a novel therapeutic class, distinct from fibrates, based on pharmacological activity, and, importantly, a safe hepatic and renal profile. The ongoing PROMINENT cardiovascular outcomes trial is testing in 10,000 patients with type 2 diabetes mellitus, elevated triglycerides, and low levels of HDL-C whether treatment with this SPPARMα agonist safely reduces residual cardiovascular risk.

An in-depth analysis shows a hidden atherogenic lipoprotein profile in non-diabetic chronic kidney disease patients

Background: Chronic kidney disease (CKD) is an independent risk factor for atherosclerotic disease. We hypothesized that CKD promotes a proatherogenic lipid profile modifying lipoprotein composition and particle number. Methods: Cross-sectional study in 395 non-diabetic individuals (209 CKD patients and 186 controls) without statin therapy. Conventional lipid determinations were combined with advanced lipoprotein profiling by nuclear magnetic resonance, and their discrimination ability was assessed by machine learning. Results: CKD patients showed an increase of very-low-density (VLDL) particles and a reduction of LDL particle size. Cholesterol and triglyceride content of VLDLs and intermediate-density (IDL) particles increased. However, low-density (LDL) and high-density (HDL) lipoproteins gained triglycerides and lost cholesterol. Total-Cholesterol, HDL-Cholesterol, LDL-Cholesterol, non-HDL-Cholesterol and Proprotein convertase subtilisin-kexin type (PCSK9) were negatively associated with CKD stages, whereas triglycerides, lipoprotein(a), remnant cholesterol, and the PCSK9/LDL-Cholesterol ratio were positively associated. PCSK9 was positively associated with total-Cholesterol, LDL-Cholesterol, LDL-triglycerides, LDL particle number, IDL-Cholesterol, and remnant cholesterol. Machine learning analysis by random forest revealed that new parameters have a higher discrimination ability to classify patients into the CKD group, compared to traditional parameters alone: area under the ROC curve (95% CI), .789 (.711, .853) vs .687 (.611, .755). Conclusions: non-diabetic CKD patients have a hidden proatherogenic lipoprotein profile.

Apolipoprotein profiling as a personalized approach to the diagnosis and treatment of dyslipidaemia

An elevated low-density lipoprotein cholesterol concentration is a classical risk factor for cardiovascular disease. This has led to pharmacotherapy in patients with atherosclerotic heart disease or high heart disease risk with statins to reduce serum low-density lipoprotein cholesterol. Even in patients in whom the target levels of low-density lipoprotein cholesterol are reached, there remains a significant residual cardiovascular risk; this is due, in part, to a focus on low-density lipoprotein cholesterol alone and neglect of other important aspects of lipoprotein metabolism. A more refined lipoprotein analysis will provide additional information on the accumulation of very low-density lipoproteins, intermediate density lipoproteins, chylomicrons, chylomicron-remnants and Lp(a) concentrations. Instead of measuring the cholesterol and triglyceride content of the lipoproteins, measurement of their apolipoproteins (apos) is more informative. Apos are either specific for a particular lipoprotein or for a group of lipoproteins. In particular measurement of apos in atherogenic particles is more biologically meaningful than the measurement of the cholesterol concentration contained in these particles. Applying apo profiling will not only improve characterization of the lipoprotein abnormality, but will also improve definition of therapeutic targets. Apo profiling aligns with the concept of precision medicine by which an individual patient is not treated as 'average' patient by the average (dose of) therapy. This concept of precision medicine fits the unmet clinical need for stratified cardiovascular medicine. The requirements for clinical application of proteomics, including apo profiling, can now be met using robust mass spectrometry technology which offers desirable analytical performance and standardization.

Association between plasma essential amino acids and atherogenic lipid profile in a Chinese population: A cross-sectional study

BACKGROUND AND AIMS

The association between amino acids and small dense low-density lipoprotein cholesterol (sdLDL-C) and remnant-like particle cholesterol (RLP-C) remains poorly understood. This study aims to investigate the association between plasma essential amino acids (EAAs) and atherogenic lipid profiles.

METHODS

Plasma amino acid levels of 475 individuals were measured using liquid chromatography-mass spectrometry. SdLDL-C, RLP-C, and other lipid components were evaluated. Associations between EAAs and lipid components or dyslipidemia were determined using correlation analysis and multivariate logistic regression.

RESULTS

Concentrations of plasma branched-chain amino acid (BCAA) were positively correlated with sdLDL-C, RLP-C, and triglycerides (TG) levels, but inversely correlated with high-density lipoprotein cholesterol (HDL-C). In contrast, threonine concentration was inversely correlated with sdLDL-C, RLP-C, and TG. Compared with the lowest tertile, individuals in the highest tertile of plasma total BCAAs level had an odds ratio (OR) of 2.33 (95% confidence interval [CI]: 1.35, 4.03) for the risk of high sdLDL-C, 3.63 (95%CI: 1.69, 7.80) for the risk of high RLP-C, 3.10 (95%CI: 1.66, 5.80) for the risk of high TG, and 3.67 (95%CI: 2.00, 6.73) for atherogenic lipid triad (all p < 0.01). In contrast, compared with the lowest tertile, individuals in the highest plasma threonine tertile had a 43% lower OR for high sdLDL-C, 56% lower OR for high TG, and 55% lower OR for lipid triad risk (all p < 0.05).

CONCLUSIONS

Among the EAAs evaluated, elevated plasma BCAAs were significantly associated with increased risk of atherogenic lipid profile. In contrast, elevated threonine was associated with reduced risk of atherogenic lipid profile.

Effects of Evolocumab on the ApoA1 Remnant Ratio: A Pooled Analysis of Phase 3 Studies

Introduction

The apolipoprotein A1 (apoA1) remnant ratio has been identified as an independent cardiovascular (CV) risk factor. Higher apoA1 remnant ratios may predict lower CV risk in some patients. This analysis aimed to evaluate the effects of evolocumab on the change from baseline in the apoA1 remnant ratio compared with placebo.

Methods

This pooled post hoc analysis included 2464 patients with mixed dyslipidemia treated with evolocumab 140 mg every 2 weeks (Q2W) or 420 mg once monthly (QM) in three phase 3 evolocumab trials. The apoA1 remnant ratio was calculated by dividing apoA1 by the difference between non-high-density lipoprotein cholesterol (non-HDL-C) and low-density lipoprotein cholesterol (LDL-C). ApoA1 remnant ratio strata were generated using previously published tertile (< 4.7, 4.7–6.8, and > 6.8) and partitioning categories (< 3.6, 3.6–6.0, and > 6.0).

Results

The baseline apoA1 remnant ratio in evolocumab and placebo treatment arms was 7.1 and 7.3, respectively. At week 12, evolocumab 140 mg Q2W and 420 mg QM increased the apoA1 remnant ratio by 25.0% and 33.6%, respectively, versus placebo (p < 0.0001 for both groups). When patients were categorized by week 12 apoA1 remnant ratio thresholds (< 3.6 vs. > 3.6, and < 4.7 vs. > 4.7), those with higher week 12 apoA1 remnant ratios were significantly more likely to have also achieved a target non-HDL-C level of < 100 mg/dl. In the subset of women > 50 years of age, the proportion of patients at apoA1 remnant ratio thresholds < 3.6, 3.6–6.0, and > 6.0 at baseline shifted toward or remained at higher thresholds at week 12.

Conclusions

This post hoc analysis suggests that evolocumab increases the apoA1 remnant ratio.

Funding

Amgen Inc.

Plain Language Summary

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Electronic supplementary material

The online version of this article (10.1007/s40119-019-0133-6) contains supplementary material, which is available to authorized users.

Hyperlipidemias and Obesity

The organs require oxygen and other types of nutrients (amino acids, sugars, and lipids) to function, the heart consuming large amounts of fatty acids for oxidation and adenosine triphosphate (ATP) generation.

Experimental therapies targeting apolipoprotein C-III for the treatment of hyperlipidemia - spotlight on volanesorsen

INTRODUCTION

Despite the substantial reduction in cardiovascular morbidity and mortality after the management of dyslipidemia with statins, residual risk remains even after achieving low-density lipoprotein cholesterol targets. This residual risk appears to be partly attributed to low levels of high-density lipoprotein cholesterol (HDL-C) and high levels of triglycerides (TG). Apolipoprotein C3 (APOC3) is a key regulator of TG metabolism and its targeting may reduce TG levels and cardiovascular risk.

AREAS COVERED

We discuss APOC3-targeted experimental treatments for dyslipidemia. There is an emphasis on volanesorsen because it the agent in the most advanced stage of development. M580, a retinoic acid receptor-α specific agonist, an agent in early-stage development is briefly covered. Preclinical data suggest that this agent decreases APOC3 mRNA levels and reduces total cholesterol, TG levels and hepatic lipid accumulation.

EXPERT OPINION

The effects of this novel therapeutic approach on cardiovascular morbidity and mortality should be determined in randomized controlled trials. The cost of volanesorsen, the unfavorable safety profile and the need for subcutaneous administration present barriers to long-term use. AM580 may hold promise in the management of hypertriglyceridemia but further investigations are necessary to evaluate safety and efficacy.