Quantifying Atherogenic Lipoproteins: Current and Future Challenges in the Era of Personalized Medicine and Very Low Concentrations of LDL Cholesterol. A Consensus Statement from EAS and EFLM

Effects of Longer-Term Mixed Nut Consumption on Lipoprotein Particle Concentrations in Older Adults with Overweight or Obesity

BACKGROUND

Recently, we reported that longer-term mixed nut intake significantly reduced serum total and low-density lipoprotein (LDL)-cholesterol, but these markers may not fully capture lipoprotein-related cardiovascular disease (CVD) risk.

OBJECTIVES

This randomized, controlled, single-blinded, crossover trial in older adults with overweight or obesity examined the effects of longer-term mixed nut consumption on lipoprotein particle size, number, and lipid distribution.

METHODS

Twenty-eight participants (aged 65 ± 3 years; BMI 27.9 ± 2.3 kg/m2) completed two 16-week periods (control [no nuts] vs. mixed nuts (60 g/day: 15 g of walnuts, pistachios, cashews, and hazelnuts), separated by an 8-week washout. Plasma lipoprotein particle numbers, sizes, and lipid distributions across subclasses were analyzed using high-throughput nuclear magnetic resonance (NMR) spectroscopy.

RESULTS

Mixed nut consumption significantly reduced Apolipoprotein B (ApoB) concentrations (-0.07 g/L; p = 0.009), total cholesterol (-0.27 mmol/L; p = 0.047), non-HDL cholesterol (-0.28 mmol/L; p = 0.022), and total triacylglycerol (TAG) (-0.27 mmol/L; p = 0.008). Total very large-density lipoprotein (VLDL) particle numbers decreased by 24 nmol/L (p < 0.001), with reductions observed across all VLDL subclasses. Total LDL particle numbers (p = 0.044), specifically intermediate-density lipoprotein (IDL) (p = 0.002) and large LDL particles (p = 0.015), were also reduced, while HDL particle numbers and sizes were unaffected. The mixed nut intervention significantly reduced cholesterol concentrations across all VLDL subclasses and IDL (all p < 0.01), with no changes in LDL or HDL subclasses. TAG concentrations showed reductions across all lipoprotein subclasses (all p < 0.05).

CONCLUSIONS

Longer-term mixed nut consumption may lower CVD risk in older adults and favorable shifts in apoB-containing lipoprotein subclasses towards a less atherogenic profile.

Apolipoprotein and peripheral artery disease: Mendelian randomization analysis

BACKGROUND

The prevalence of peripheral arterial disease (PAD) is on the rise globally, leading to adverse clinical outcomes. Our aim was to investigate the causal relationship between apolipoprotein and PAD, as well as the potential mediating role of smoking, diabetes, hypertension, myocardial infarction, and ischemic stroke.

METHODS

We employed two-sample Mendelian randomization (TSMR) to assess the causal effect of apoB/A1 on the risk of PAD and potential mediators (smoking, diabetes mellitus, hypertension, myocardial infarction, and ischemic stroke), as well as the causal effect of those mediators on PAD. The use of multivariate MR (MVMR) allowed us to explore and quantify the mediating role of these factors in the causal association between apoB/A1 and the risk of PAD.

RESULTS

Our MR analysis showed that each standard deviation increase in apoB/A1 increased the risk of PAD by 46% (OR = 1.460, 95% CI: 1.255-1.697, P = 8.74E-07). Hypertension, myocardial infarction, and ischemic stroke were ultimately recognized as the mediators of the causal relationship between apoB/A1 and PAD, explaining 7.5%, 19.7%, and 62.5% of the causal effect, respectively, and the proportion combined of the three together was 81%.

CONCLUSIONS

These studies demonstrated that elevated apoB/A1 increases the risk of developing PAD and that this association may be mediated by hypertension, myocardial infarction, and ischemic stroke.

Windows of Susceptibility to Air Pollution During and Surrounding Pregnancy in Relation to Longitudinal Maternal Measures of Adiposity and Lipid Profiles

Pregnancy is a critical window for long-term metabolic programming of fetal effects stemming from airborne particulate matter ≤2.5μm (PM 2.5 ) exposure. Yet, little is known about long-term metabolic effects of PM 2.5 exposure during and surrounding pregnancy in mothers. We assessed potential critical windows of PM 2.5 exposure during and surrounding pregnancy with maternal adiposity and lipid measures later in life. We included 517 pregnant women from the PROGRESS cohort with adiposity [body mass index (BMI), waist circumference (WC), % body fat] and lipids [total cholesterol, high-density-lipoprotein (HDL), low-density-lipoprotein (LDL)] measured repeatedly at 4, 6 and 8 years post-delivery. Monthly average PM 2.5 exposure was estimated at each participant's address using a validated spatiotemporal model. We employed distributed lag interaction models (DLIMs) adjusting for socio-demographics and clinical covariates. We found that a 1 μg/m 3 increase in PM 2.5 exposure throughout mid-/late-pregnancy was associated with higher WC at 6-years post-delivery, peaking at 6 months of gestation: 0.04 cm (95%CI: 0.01, 0.06). We also identified critical windows of PM 2.5 exposure during and surrounding pregnancy associated with higher LDL and lower HDL both measured at 4 years post-delivery with peaks at pre-conception for LDL [0.17 mg/dL (95%CI: 0.00, 0.34)] and at the 11 th month after conception for HDL [-0.07 mg/dL (95%CI: -0.11, -0.02)]. Stratified analyses by fetal sex indicated stronger associations with adiposity measures in mothers carrying a male, whereas stronger associations were observed with lipids in mothers carrying a female fetus. Stratified analyses also indicated potential stronger deleterious lagged effects in women with folic acid intake lower than 600mcg/day during pregnancy.

Associations of per- and polyfluoroalkyl substances and heavy metals with blood lipid profiles in a representative sample of Korean adolescents

BACKGROUND

Previous studies on the associations of per- and polyfluoroalkyl substances (PFASs) and heavy metals with lipid profiles among adolescents have been scarce. We sought to investigate the associations of PFASs and heavy metals with blood lipid levels in a representative sample of Korean adolescents.

METHODS

Data from the Korean National Environmental Health Survey (2018-2020) were used. Concentrations of PFASs [perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid, perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDeA)], lead, and mercury were measured in serum, whole blood, and urine samples, respectively. Linear regression, Bayesian kernel machine regression (BKMR), and k-means clustering analyses were employed to evaluate the associations between pollutants and lipid levels.

RESULTS

In the linear regression analyses, PFOA levels were associated with higher low-density lipoprotein cholesterol (LDL-C) levels; PFOS with higher total cholesterol (TC) levels; PFNA with higher TC, LDL-C, and non-high-density lipoprotein cholesterol (non-HDL-C) levels; PFDeA with higher TC, LDL-C, non-HDL-C, and high-density lipoprotein cholesterol levels; and mercury with higher TC and non-HDL-C levels. The BKMR analysis revealed that the PFAS and heavy metal mixture was associated with higher LDL-C levels (1.8% increase in LDL-C at the 75th percentile of all PFAS and heavy metal concentrations compared to their median values, 95% credible interval: 0.5, 3.1), primarily driven by the effect of PFDeA. Compared to individuals in the low pollutant exposure cluster (geometric mean levels of PFOA, PFOS, PFHxS, PFNA, PFDeA, lead, and mercury were 2.7 μg/L, 6.2 μg/L, 1.6 μg/L, 0.7 μg/L, 0.4 μg/L, 0.8 μg/dL, and 0.3 μg/L, respectively), those in the high pollutant exposure cluster (5.1 μg/L, 10.7 μg/L, 3.7 μg/L, 1.3 μg/L, 0.6 μg/L, 0.9 μg/dL, and 0.4 μg/L, respectively) demonstrated higher TC levels (2.5% increase in TC, 95% confidence interval: 0.1, 5.0) in the k-means clustering analysis.

CONCLUSION

Due to the limitations of this study, such as its cross-sectional design, these results should be interpreted cautiously and confirmed in future studies before drawing implications for public health strategies aimed at promoting health during adolescence and later in life.

Quality Assurance for Multiplex Quantitative Clinical Chemistry Proteomics in Large Clinical Trials

BACKGROUND

To evaluate the clinical performance and effectiveness of a multiplex apolipoprotein panel in the context of cardiovascular precision diagnostics, clinical samples of patients with recent acute coronary syndrome in the ODYSSEY OUTCOMES trial were measured by quantitative clinical chemistry proteomics (qCCP). The ISO15189-accredited laboratory setting, including the total testing process (TTP), served as a foundation for this study. Consequently, tailored quality assurance measures needed to be designed and implemented to suit the demands of a multiplex LC-MS/MS test.

METHODS

Nine serum apolipoproteins were measured in 23 376 samples with a laboratory-developed multiplex apolipoprotein test on 4 Agilent 6495 LC-MS/MS systems. A fit-for-purpose process was designed with tailored additions enhancing the accredited laboratory infrastructure and the TTP. Quality assurance was organized in 3 steps: system suitability testing (SST), internal quality control (IQC) evaluation with adjusted Westgard rules to fit a multiplex test, and interpeptide agreement analysis. Data was semi-automatically evaluated with a custom R script.

RESULTS

LC-MS/MS analyses were performed with the following between-run CVs: for apolipoprotein (Apo) (a) 6.2%, Apo A-I 2.3%, Apo A-II 2.1%, Apo A-IV 2.9%, Apo B 1.9%, Apo C-I 3.3%, Apo C-II 3.3%, Apo C-III 2.7%, and for Apo E 3.3% and an average interpeptide agreement Pearson r of 0.981.

CONCLUSIONS

This is the first study of its kind in which qCCP was performed at this scale. This research successfully demonstrates the feasibility of high-throughput LC-MS/MS applications in large clinical trials. ClinicalTrials.gov Registration Number: NCT01663402.

Lipoprotein(a) and cardiovascular disease

One in five people are at high risk for atherosclerotic cardiovascular disease and aortic valve stenosis due to high lipoprotein(a). Lipoprotein(a) concentrations are lowest in people from east Asia, Europe, and southeast Asia, intermediate in people from south Asia, the Middle East, and Latin America, and highest in people from Africa. Concentrations are more than 90% genetically determined and 17% higher in post-menopausal women than in men. Individuals at a higher cardiovascular risk should have lipoprotein(a) concentrations measured once in their lifetime to inform those with high concentrations to adhere to a healthy lifestyle and receive medication to lower other cardiovascular risk factors. With no approved drugs to lower lipoprotein(a) concentrations, it is promising that at least five drugs in development lower concentrations by 65-98%, with three currently being tested in large cardiovascular endpoint trials. This Review covers historical perspectives, physiology and pathophysiology, genetic evidence of causality, epidemiology, role in familial hypercholesterolaemia and diabetes, management, screening, diagnosis, measurement, prevention, and future lipoprotein(a)-lowering drugs.

Lipoprotein(a) and risk-weighted apolipoprotein B: a novel metric for atherogenic risk

BACKGROUND

Retention of apolipoprotein B (apoB)-containing lipoproteins within the arterial wall plays a major causal role in atherosclerotic cardiovascular disease (ASCVD). There is a single apoB molecule in all apoB-containing lipoproteins. Therefore, quantitation of apoB directly estimates the number of atherogenic particles in plasma. ApoB is the preferred measurement to refine the estimate of ASCVD risk. Low-density lipoprotein (LDL) particles are by far the most abundant apoB-containing particles. In patients with elevated lipoprotein(a) (Lp(a)), apoB may considerably underestimate risk because Mendelian randomization studies have shown that the atherogenicity of Lp(a) is approximately 7-fold greater than that of LDL on a per apoB particle basis. In subjects with increased Lp(a), the association between LDL-cholesterol and incident CHD (coronary heart disease) is increased, but the association between apoB and incident CHD is diminished or even lost. Thus, there is a need to understand the mechanisms of Lp(a), LDL-cholesterol and apoB-related CHD risk and to provide clinicians with a simple practical tool to address these complex and variable relationships. How can we understand a patient's overall lipid-driven atherogenic risk? What proportion of this risk does apoB capture? What proportion of this risk do Lp(a) particles carry? To answer these questions, we created a novel metric of atherogenic risk: risk-weighted apolipoprotein B.

METHODS

In nmol/L: Risk-weighted apoB = apoB - Lp(a) + Lp(a) x 7 = apoB + Lp(a) x 6. Proportion of risk captured by apoB = apoB divided by risk-weighted apoB. Proportion of risk carried by Lp(a) = Lp(a) × 7 divided by risk-weighted apoB.

RESULTS

Risk-weighted apoB agrees with risk estimation from large epidemiological studies and from several Mendelian randomization studies.

CONCLUSIONS

ApoB considerably underestimates risk in individuals with high Lp(a) levels. The association between apoB and incident CHD is diminished or even lost. These phenomena can be overcome and explained by risk-weighted apoB.

Low prevalence of testing for apolipoprotein B and lipoprotein (a) in the real world

Objective

Apolipoprotein B (ApoB) and lipoprotein (a) (Lp[a]) are predictors of cardiovascular disease (CVD) risk; therefore, current recommendations for CVD risk assessment and management advocate that patients receive testing for ApoB and Lp(a) in addition to the standard lipid panel. However, US guidelines around ApoB and Lp(a) testing have evolved over time and vary slightly by expert committee. The objective of this analysis was to estimate the number of insured individuals in the USA who received any component of a lipid test, or ApoB and/or Lp(a) testing, during 2019.

Methods

We conducted a cross-sectional analysis to estimate the prevalence of any component of a lipid test, ApoB, and/or Lp(a) in the USA using four different claim data sources (including Medicaid, Medicare, and commercially insured enrollees). Prevalence estimates were age-, sex-, payor-, and region-standardized to the 2019 US Annual Social and Economic Supplement of the Current Population Survey. We also described the clinical profile of patients who received lipid testing between 2019 and 2021 (cohort analysis) in Optum claims database. Enrollees were grouped into four non-mutually exclusive cohorts based on their completion of any component of the lipid panel, ApoB, Lp(a), or ApoB and Lp(a).

Results

In the prevalence cohort, over a third (38 %) of insured adults in the USA underwent testing for any component of a lipid panel in 2019. This proportion was higher for individuals aged ≥65 years compared to younger adults (62% vs 31 %). The proportion of ApoB and Lp(a) testing represented only <1 % of testing for any component of a lipid panel. In the cohort analysis, we found that lipid testing increased with age and comorbidities.

Conclusion

These data should be considered by guideline-issuing agencies and organizations to develop education campaigns encouraging more frequent use of tests beyond the standard lipid panel.

Discordance among apoB, non-high-density lipoprotein cholesterol, and triglycerides: implications for cardiovascular prevention

BACKGROUND AND AIMS

Despite growing evidence that apolipoprotein B (apoB) is the most accurate marker of atherosclerotic cardiovascular disease (ASCVD) risk, its adoption in clinical practice has been low. This investigation sought to determine whether low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (HDL-C), and triglycerides are sufficient for routine cardiovascular care.

METHODS

A sample of 293 876 UK Biobank adults (age: 40-73 years, 42% men), free of cardiovascular disease, with a median follow-up for new-onset ASCVD of 11 years was included. Distribution of apoB at pre-specified levels of LDL-C, non-HDL-C, and triglycerides was examined graphically, and 10-year ASCVD event rates were compared for high vs. low apoB. Residuals of apoB were constructed after regressing apoB on LDL-C, non-HDL-C, and log-transformed triglycerides and used as predictors in a proportional hazards regression model for new-onset ASCVD adjusted for standard risk factors, including HDL-C.

RESULTS

ApoB was highly correlated with LDL-C and non-HDL-C (Pearson's r = .96, P < .001 for both) but less so with log triglycerides (r = .42, P < .001). However, apoB ranges necessary to capture 95% of all observations at pre-specified levels of LDL-C, non-HDL-C, or triglycerides were wide, spanning 85.8-108.8 md/dL when LDL-C 130 mg/dL, 88.3-112.4 mg/dL when non-HDL-C 160 mg/dL, and 67.8-147.4 md/dL when triglycerides 115 mg/dL. At these levels (±10 mg/dL), 10-year ASCVD rates for apoB above mean + 1 SD vs. below mean - 1 SD were 7.3 vs. 4.0 for LDL-C, 6.4 vs. 4.6 for non-HDL-C, and 7.0 vs. 4.6 for triglycerides (all P < .001). With 19 982 new-onset ASCVD events on follow-up, in the adjusted model, residual apoB remained statistically significant after accounting for LDL-C and HDL-C (hazard ratio 1.06, 95% confidence interval 1.0-1.07), after accounting for non-HDL-C and HDL-C (hazard ratio 1.04, 95% confidence interval 1.03-1.06), and after accounting for triglycerides and HDL-C (hazard ratio 1.13, 95% confidence interval 1.12-1.15). None of the residuals of LDL-C, non-HDL-C, or of log triglycerides remained significant when apoB was included in the model.

CONCLUSIONS

High variability of apoB at individual levels of LDL-C, non-HDL-C, and triglycerides coupled with meaningful differences in 10-year ASCVD rates and significant residual information contained in apoB for prediction of new-onset ASCVD events demonstrate that LDL-C, non-HDL-C, and triglycerides are not adequate proxies for apoB in clinical care.

Efficacy of Alirocumab, Evolocumab, and Inclisiran in Patients with Hypercholesterolemia at Increased Cardiovascular Risk

Background and Objectives: Lowering low-density lipoprotein (LDL-C) levels is critical for preventing atherosclerotic cardiovascular disease, yet some patients fail to reach the LDL-C targets despite available intensive lipid-lowering therapies. This study assessed the effectiveness and safety profile of alirocumab, evolocumab, and inclisiran in lipid reduction. Materials and Methods: A cohort of 51 patients (median (Q1-Q3) age: 49.0 (39.5-57.5) years) was analyzed. Eligibility included an LDL-C level > 2.5 mmol/L while on the maximum tolerated dose of statin and ezetimibe, a diagnosis of familial hypercholesterolemia, or a very high risk of cardiovascular diseases following myocardial infarction within 12 months prior to the study. Follow-ups and lab assessments were conducted at baseline (51 patients), 3 months (51 patients), and 15 months (26 patients) after the treatment initiation. Results: Median initial LDL-C levels 4.1 (2.9-5.0) mmol/L, decreasing significantly to 1.1 (0.9-1.6) mmol/L at 3 months and 1.0 (0.7-1.8) mmol/L at 15 months (p < 0.001). Total cholesterol also reduced significantly compared to baseline at both intervals (p < 0.001). No substantial differences in LDL-C or total cholesterol levels were observed between 3- and 15-month observations (p > 0.05). No statistically significant differences were noted in cholesterol reduction among the alirocumab, evolocumab, and inclisiran groups at 3 months. The safety profile was favorable, with no reported adverse cardiovascular events or significant changes in alanine transaminase, creatinine, or creatine kinase levels. Conclusions: Alirocumab, evolocumab, and inclisiran notably decreased LDL-C and total cholesterol levels without significant adverse effects, underscoring their potential as effective treatments in patients who do not achieve lipid targets with conventional therapies.

Worldwide Increasing Use of Nonfasting Rather Than Fasting Lipid Profiles

BACKGROUND

Historically, lipids and lipoproteins were measured in the fasting state for cardiovascular risk prediction; however, since 2009 use of nonfasting lipid profiles has increased substantially worldwide. For patients, nonfasting lipid profiles are convenient and avoid any risk of hypoglycemia. For laboratories, blood sampling in the morning and extra visits for patients who have not fasted are avoided. For patients, clinicians, hospitals, and society, nonfasting sampling allows same-day visits with first blood sampling followed by a short wait for test results before clinical consultation. Therefore, nonfasting compared to fasting lipid profiles will save money and time and may improve patient compliance with cardiovascular prevention programs.

CONTENT

We report on the progression of endorsement and implementation of nonfasting lipid profiles for cardiovascular risk prediction worldwide and summarize the recommendations from major medical societies and health authorities in different countries. We also describe practical advantages and disadvantages for using nonfasting lipid profiles. Further, we include a description of why fasting has been the standard historically, the barriers against implementation of nonfasting lipid profiles, and finally we suggest the optimal content of a nonfasting lipid profile.

SUMMARY

Lipid, lipoprotein, and apolipoprotein concentrations vary minimally in response to normal food intake and nonfasting lipid profiles are equal or superior to fasting profiles for cardiovascular risk prediction. Major guidelines and consensus statements in Europe, the United States, Canada, Brazil, Japan, India, and Australia now endorse use of nonfasting lipid profiles in some or all patients; however, there are still gaps in endorsement and implementation of nonfasting lipid profiles worldwide.

Excess Apolipoprotein B and Cardiovascular Risk in Women and Men

BACKGROUND

Low-density lipoprotein cholesterol (LDL-C) and apolipoprotein B (apoB) are highly correlated measures of atherogenic lipoproteins.

OBJECTIVES

The study investigators hypothesized that excess apoB is associated with an increased risk of myocardial infarction (MI), atherosclerotic cardiovascular disease (ASCVD), and all-cause mortality.

METHODS

The study included 53,484 women and 41,624 men not taking statins from the Copenhagen General Population Study. Associations of excess apoB with the risk of MI, ASCVD, and all-cause mortality were estimated by Cox proportional hazards regressions with 95% CIs. Excess apoB was defined as measured levels of apoB minus expected levels of apoB from LDL-C alone; expected levels were defined by linear regressions of LDL-C levels vs apoB levels in individuals with triglycerides ≤1 mmol/L (89 mg/dL).

RESULTS

During a median follow-up of 9.6 years, 2,048 MIs, 4,282 ASCVD events, and 8,873 deaths occurred. There was a dose-dependent association between excess apoB and the risk of MI and ASCVD in both women and men, as well as an association with the risk of all-cause mortality in women. For ASCVD in women compared with those with excess apoB <11 mg/dL, the multivariable adjusted HR was 1.08 (95% CI: 0.97-1.21) for excess apoB 11 to 25 mg/dL, 1.30 (95% CI: 1.14-1.48) for 26 to 45 mg/dL, 1.34 (95% CI: 1.14-1.58) for 46 to 100 mg/dL, and 1.75 (95% CI: 1.08-2.83) for excess apoB >100 mg/dL. Corresponding HRs in men were 1.14 (95% CI: 1.02-1.26), 1.41 (95% CI: 1.26-1.57), 1.41 (95% CI: 1.25-1.60), and 1.52 (95% CI: 1.13-2.05), respectively. Results were robust across the entire LDL-C spectrum.

CONCLUSIONS

Excess apoB (ie, the value of apoB above that contributed by LDL-C levels alone) is associated dose-dependently with an increased risk of MI and ASCVD in women and men. This finding demonstrates that apoB provides important predictive value beyond LDL-C across the entire LDL-C spectrum.

Could the association between ozone and arterial stiffness be modified by fish oil supplementation?

BACKGROUND

Arterial stiffness (AS) is an important predicting factor for cardiovascular disease. However, no epidemiological studies have ever explored the mediating role of biomarkers in the association between ozone and AS, nor weather fish oil modified such association.

METHODS

Study participants were drawn from the UK biobank, and a total of 95,699 middle-aged and older adults were included in this study. Ozone was obtained from Community Multiscale Air Quality (CMAQ) model matched to residential addresses, fish oil from self-reported intake, and arterial stiffness was based on device measurements. First, we applied a double robust approach to explore the association between ozone or fish oil intake and arterial stiffness, adjusting for potential confounders at the individual and regional levels. Then, how triglycerides, apolipoprotein B (Apo B)/apolipoprotein A (ApoA) and non-high-density lipoprotein cholesterol (Non-HDL-C) mediate the relationship between ozone and AS. Last, the modifying role of fish oil was further explored by stratified analysis.

RESULTS

The mean age of participants was 55 years; annual average ozone exposure was associated with ASI (beta:0.189 [95%CI: 0.146 to 0.233], P < 0.001), and compared to participants who did not consume fish oil, fish oil users had a lower ASI (beta: 0.061 [95%CI: -0.111 to -0.010], P = 0.016). The relationship between ozone exposure and AS was mediated by triglycerides, ApoB/ApoA, and Non-HDL-C with mediation proportions ranging from 10.90% to 18.30%. Stratified analysis showed lower estimates on the ozone-AS relationship in fish oil users (P = 0.011).

CONCLUSION

Ozone exposure was associated with higher levels of arterial stiffness, in contrast to fish oil consumption, which showed a protective association. The association between ozone exposure and arterial stiffness was partially mediated by some biomarkers. In the general population, fish oil consumption might provide protection against ozone-related AS.

Remnant cholesterol trajectory and subclinical arteriosclerosis: a 10-year longitudinal study of Chinese adults

We aimed to identify different trajectories of remnant cholesterol (RC) and investigate the association of RC trajectories with vascular endothelial function and atherosclerosis progression in a longitudinal cohort of the Chinese population. A total of 521 participants were included in the flow-mediated vasodilation (FMD) subcohort study, and 7775 participants were included in the brachial-ankle pulse wave velocity (baPWV) subcohort study. All participants had ≥ 3 medical examinations during the 10-year follow-up period. In the FMD subcohort study, three distinct RC trajectories were identified according to the RC range and changing pattern over time: "low" (57.58%), "moderate" (30.90%) and "high" (11.52%). The proportion of the three groups with vascular endothelial dysfunction (FMD < 7.0%) was 20.00%, 39.75% and 60.00% respectively. Taking the low group as a reference, participants in the moderate and high groups had over 1.88 and 2.94 times the odds of vascular endothelial dysfunction (P = 0.048). In the baPWV subcohort study, three distinct RC trajectories were also identified: "low" (54.29%), "moderate" (38.97%) and "high" (6.74%). The proportion of the three groups with atherosclerosis (baPWV > 1400 cm/s) was 38.79%, 51.26% and 59.01% respectively. Taking the low group as a reference, participants in the moderate and high groups had over 1.46 and 2.16 times the odds of atherosclerosis (P < 0.001). The findings indicated that distinct RC trajectories are significantly associated with vascular endothelial function and atherosclerosis. Regular monitoring to identify persistent increases in RC may be more helpful in identifying individuals with a high risk of cardiovascular disease.

A comparative evaluation of low-density lipoprotein cholesterol estimation: Machine learning algorithms versus various equations

BACKGROUND

Given the critical importance of Low-density lipoprotein cholesterol (LDL-C) levels in determining cardiovascular risk, it is essential to measure LDL-C accurately. Since the Friedewald formula generates incorrect predictions in many circumstances, new equations have been developed to overcome the Friedewald equations' shortcomings. This study aimed to compare estimated LDL-C with directly measured LDL-C (dLDL-C), as well as their performance in predicting LDL-C, utilizing Friedewald, extended Martin-Hopkins, Sampson, de Cordova, and Vujovic formulas and five machine learning (ML) algorithms.

METHODS

A total of 29,504 samples from the ISLAB-2 Core Laboratory were included in the study. All statistical analysis was performed using R version 4.1.2. Statistical Language.

RESULTS

Bayesian-Regularized Neural Network (BRNN) (r = 0.957) and Random Forest (RF) (r = 0.957) algorithms showed a higher correlation with dLDL-C than the other equations in all-testing dataset. All ML algorithms demonstrated less bias than pre-existing LDL-C equations with dLDL-C and outperformed the LDL-C estimation equations in terms of concordance in all-testing dataset.

CONCLUSIONS

The results of our research indicate that when compared to conventional equations, ML algorithms are much more effective in predicting LDL-C. ML algorithms, aided by a vast dataset, could have the capability to predict LDL-C levels even in cases where triglyceride levels are high, unlike the limited usage of Friedewald formula.

Association of non-HDL-C/apoB ratio with long-term mortality in the general population: A cohort study

BACKGROUND

In general, the identification of cholesterol-depleted lipid particles can be inferred from non-high-density lipoprotein cholesterol (non-HDL-C) concentration to apolipoprotein B (apoB) concentration ratio, which serves as a reliable indicator for assessing the risk of cardiovascular disease. However, the ability of non-HDL-C/apoB ratio to predict the risk of long-term mortality among the general population remains uncertain. The aim of this study is to explore the association of non-HDL-C/apoB ratio with long-term all-cause and cardiovascular mortality in adults of the United States.

METHODS

This retrospective cohort study was a further analysis of existing information from the National Health and Nutrition Examination Survey (NHANES). In the ultimate analysis, 12,697 participants from 2005 to 2014 were included. Kaplan-Meier (K-M) curves and the log-rank test were applied to visualize survival differences between groups. Multivariate Cox regression and restricted cubic spline (RCS) models were applied to evaluate the association of non-HDL-C/apoB ratio with all-cause and cardiovascular mortality. Subgroup analysis was conducted for the variables of age, sex, presence of coronary artery disease, diabetes and hypertriglyceridemia and usage of lipid-lowering drugs.

RESULTS

The average age of the cohort was 46.8 ± 18.6 years, with 6215 (48.9%) participants being male. During a median follow-up lasting 68.0 months, 891 (7.0%) deaths were documented and 156 (1.2%) patients died of cardiovascular disease. Individuals who experienced all-cause and cardiovascular deaths had a lower non-HDL-C/apoB ratio compared with those without events (1.45 ± 0.16 vs. 1.50 ± 0.17 and 1.43 ± 0.17 vs. 1.50 ± 0.17, both P values < 0.001). The results of adjusted Cox regression models revealed that non-HDL-C/apoB ratio exhibited independent significance as a risk factor for both long-term all-cause mortality [hazard ratio (HR) = 0.51, 95% confidence interval (CI): 0.33-0.80] and cardiovascular mortality (HR = 0.33, 95% CI: 0.12-0.90). Additionally, a significant sex interaction was discovered (P for interaction <0.05), indicating a robust association between non-HDL-C/apoB ratio and long-term mortality among females. The RCS curve showed that non-HDL-C/apoB ratio had a negative linear association with long-term all-cause and cardiovascular mortality (P for non-linearity was 0.098 and 0.314).

CONCLUSIONS

The non-HDL-C/apoB ratio may serve as a potential biomarker for predicting long-term mortality among the general population, independent of traditional risk factors.

Closing the gaps in patient management of dyslipidemia: stepping into cardiovascular precision diagnostics with apolipoprotein profiling

In persons with dyslipidemia, a high residual risk of cardiovascular disease remains despite lipid lowering therapy. Current cardiovascular risk prediction mainly focuses on low-density lipoprotein cholesterol (LDL-c) levels, neglecting other contributing risk factors. Moreover, the efficacy of LDL-c lowering by statins resulting in reduced cardiovascular risk is only partially effective. Secondly, from a metrological viewpoint LDL-c falls short as a reliable measurand. Both direct and calculated LDL-c tests produce inaccurate test results at the low end under aggressive lipid lowering therapy. As LDL-c tests underperform both clinically and metrologically, there is an urging need for molecularly defined biomarkers. Over the years, apolipoproteins have emerged as promising biomarkers in the context of cardiovascular disease as they are the functional workhorses in lipid metabolism. Among these, apolipoprotein B (ApoB), present on all atherogenic lipoprotein particles, has demonstrated to clinically outperform LDL-c. Other apolipoproteins, such as Apo(a) - the characteristic apolipoprotein of the emerging risk factor lipoprotein(a) -, and ApoC-III - an inhibitor of triglyceride-rich lipoprotein clearance -, have attracted attention as well. To support personalized medicine, we need to move to molecularly defined risk markers, like the apolipoproteins. Molecularly defined diagnosis and molecularly targeted therapy require molecularly measured biomarkers. This review provides a summary of the scientific validity and (patho)physiological role of nine serum apolipoproteins, Apo(a), ApoB, ApoC-I, ApoC-II, ApoC-III, ApoE and its phenotypes, ApoA-I, ApoA-II, and ApoA-IV, in lipid metabolism, their association with cardiovascular disease, and their potential as cardiovascular risk markers when measured in a multiplex apolipoprotein panel.

Association of APO B gene polymorphisms with the development of myocardial infarction in Pakistani population

Myocardial infarction (MI) is when a blood clot in the coronary artery obstructs blood flow to a specific part of the heart, leading to the death of myocardium in that area. The development of MI is influenced by various environmental factors, genetic components, and their interactions, even though the exact cause has not been fully established. This is the first case-control study examining the possible association between the human Apo B gene and MI in the Punjab region of Pakistan. The study included 100 patients and 50 healthy individuals. Genomic DNA was isolated from blood samples using manual extraction methods. Subsequently, primers were optimized, and genotyping was performed using PCR, followed by DNA sequencing and RFLP analysis. The research focused on two specific APO B gene SNPs, codon 4154 G/A (rs1801701) and codon 2488 G/A (rs1042031). Both SNPs involved the substitution of guanine with adenine. It was found that individuals carrying the minor allele A of SNP rs1801701 (p < 0.001) and the minor allele A of rs1042031 (p < 0.001) had a significantly higher risk of developing MI. Additionally, haplotype analysis revealed that the AA haplotype (comprising both rs1801701 and rs1042031 SNPs) was associated with a substantially increased risk of MI (OR = 3.845). In conclusion, the study provides evidence supporting the association between specific mutations in the APOB gene and the risk of myocardial infarction in the Pakistani population.

Elevated lipoprotein(a) increases risk of subsequent major adverse cardiovascular events (MACE) and coronary revascularisation in incident ASCVD patients: A cohort study from the UK Biobank

BACKGROUND AND AIMS

Elevated lipoprotein(a) [Lp(a)] is a genetic driver for atherosclerotic cardiovascular disease (ASCVD). We aimed to provide novel insights into the associated risk of elevated versus normal Lp(a) levels on major adverse cardiovascular events (MACE) in an incident ASCVD cohort.

METHODS

This was an observational cohort study of incident ASCVD patients. MACE counts and incidence rates (IRs) per 100-person-years were reported for patients with normal (<65 nmol/L) and elevated (>150 nmol/L) Lp(a) within the first year after incident ASCVD diagnosis and overall follow-up. Cox proportional hazard models quantified the risk of MACE associated with a 100 nmol/L increase in Lp(a).

RESULTS

The study cohort included 32,537 incident ASCVD patients; 5204 with elevated and 22,257 with normal Lp(a). Of those with elevated Lp(a), 41.2% had a subsequent MACE, versus 35.61% with normal Lp(a). Within the first year of follow-up, the IRs of composite MACE and coronary revascularisation were significantly higher (p < 0.001) in patients with elevated versus normal Lp(a) (IR difference 6.79 and 4.66). This trend was also observed in the overall follow-up (median 4.7 years). Using time to first subsequent MACE, a 100 nmol/L increase in Lp(a) was associated with an 8.0% increased risk of composite MACE, and 18.6% increased risk of coronary revascularisation during the overall follow-up period.

CONCLUSIONS

The association of elevated Lp(a) with increased risk of subsequent MACE and coronary revascularisation highlights a population who may benefit from earlier and more targeted intervention for cardiovascular risk including Lp(a), particularly within the first year after ASCVD diagnosis. Proactive Lp(a) testing as part of routine clinical practice can help identify and better manage these higher-risk individuals.

Adherence to the Mediterranean diet and nuclear magnetic resonance spectroscopy biomarkers in older individuals at high cardiovascular disease risk: cross-sectional and longitudinal analyses

BACKGROUND

The Mediterranean diet (MedDiet) has been related to a decreased risk of cardiovascular disease (CVD) and diabetes.

OBJECTIVES

We aimed to prospectively assess the relationship between adherence to the MedDiet and advanced lipoprotein subclass profiles and glucose metabolism and inflammation markers, as determined by nuclear magnetic resonance (NMR) spectroscopy.

DESIGN

We conducted cross-sectional and longitudinal analyses within the framework of the PREvención con DIeta MEDiterránea study in 196 participants from the Reus-Tarragona center. Adherence to the MedDiet was assessed using a 14-item validated questionnaire [Mediterranean Diet Adherence Score (MEDAS)]. Plasma lipoprotein subclasses and molecular metabolite profiles were determined using NMR spectra collected on a Vantera Clinical Analyzer at baseline and after 1 y of follow-up. Baseline and 1-y categories of MEDAS were related to measures of lipoprotein atherogenicity and diabetes risk using multivariable-adjusted analysis of covariance models.

RESULTS

Compared with participants in the lowest category of baseline MEDAS, those in the highest category showed higher concentrations of total high-density lipoprotein (HDL) particles and H1P HDL, lower concentrations of very low-density lipoprotein (VLDL)-triglyceride, smaller size of VLDL, and lower concentrations of very large VLDL, as well as lower concentrations of branched-chain amino acids, leucine, and GlycA and reduced Diabetes Risk Index (DRI) scores. In addition, participants who increased by 3 or more points in their 1-y MEDAS showed an increase in concentrations of H7P-HDL, H5P-HDL, and citrate, and reduced acetone and DRI scores compared with those with lesser adherence increases.

CONCLUSIONS

In older adults at high cardiometabolic risk, higher MEDAS was associated with modest beneficial changes in lipoprotein and glucose metabolism. The results suggest that lipoprotein subclass distribution and glycemic control are potential mechanisms behind the well-known salutary effects of MedDiet on CVD and diabetes risk. Future clinical trials exploring the effects of the MedDiet on advanced lipoprotein subclass profiles and glucose metabolism markers are needed to confirm the results of our study.

TRIAL REGISTRATION NUMBER

This trial was registered at controlled-trials.com as ISRCTN35739639.

Reference Interval for Non-HDL-Cholesterol, Remnant Cholesterol and Other Lipid Parameters in the Southern Iranian Population; Findings From Bandare Kong and Fasa Cohort Studies

BACKGROUND

Growing evidence shows the undisputable role of non-HDL-C and remnant cholesterol (remnant-C) in cardiovascular disease (CVD) risk assessment and treatment. However, the reference interval (RI) for these lipid parameters is not readily available. The aim of the present investigation was to determine the age and sex-specific RIs for non-HDL-C and remnant-C as well as other lipid parameters among a healthy population in southern Iran. We also report the RI of lipid parameters in rural and urban residents, smokers and post-menopausal women.

METHODS

Among 14063 participants of Bandare Kong and Fasa cohort studies, 792 healthy subjects (205 men and 578 women) aged 35-70 years were selected. Fasting blood samples were used for determination of total cholesterol (TC), triglycerides (TG) and HDL-C using colorimetric methods. Non-HDL-C and remnant-C were calculated using the valid formula. The 2.5th and 97.5th percentiles were calculated and considered as RI.

RESULTS

In the total population (n=792, age 35-70), RIs for non-HDL-C and remnant-C was 74.0-206.8 and 8.0-52.7 mg/dL, respectively. Age (35-44 and≥45 years) and gender-specific RIs for serum non-HDL-C and remnant-C were determined. Remnant-C and non-HDL-C level were different between sex and age categories. The mean value of all lipid parameters except HDL-C was higher in men, urban residents, subject with age≥45 years and smokers.

CONCLUSION

This is the first study in which the RIs for non-HDL-C and remnant-C in southern Iran are reported. This may help physicians to conveniently use these lipid parameters for patient care and better cardiovascular risk assessment.

Performance of the enhanced Sampson-NIH equation for VLDL-C and LDL-C in a population with familial combined hyperlipidemia

INTRODUCTION

Low-density cholesterol (LDL-C) has long been estimated by the Friedewald formula (F-LDL-C); however, this method underestimates LDL-C in patients with hypertriglyceridemia (HTG) or low LDL-C levels. The Martin (M-LDL-C) and Sampson (S-LDL-C) formulas partially resolve these limitations. Recently, Sampson et al. developed a new equation (eS-VLDL-C) that includes ApoB. This new equation could be particularly useful in FCHL, which is characterized by the predominance of triglyceride-rich VLDL and a discordance between LDL-C and ApoB.

METHODS

Very low-density lipoproteins (VLDL-C) was measured in 336 patients with FCHL by sequential ultracentrifugation. LDL-C was estimated by subtracting VLDL-C, estimated by the different equations, from non-HDL cholesterol. Spearman correlations, R2, mean squared error (RMSE), and bias were used to compare the accuracy of the different equations. Concordance of the estimated LDL-C values with LDL-C thresholds and ApoB was also assessed by their kappa coefficients and ROC analysis.

RESULTS

Overall population had a mean age of 47 years, and 61.5% were women. 19.5% had type 2 diabetes, hypertension was present in 20.8%, and only 12.2% were on statin treatment. Both S-LDL-C and eS-LDL-C performed similarly, and better than M-LDL-C and F-LDL-C. In Bland-Altman analysis, eS-LDL-C showed the lowest bias, better performance in HTG, and better concordance with LDL-C treatment goals compared to other formulas (e.g. ρ: 0.87, 95% CI 0.84-0.89).

CONCLUSIONS

LDL-S and LDL-eS equations estimate the concentration of LDL-C with greater accuracy than other formulas. The LDL-eS has best performance in estimating LDL-C with lower RMSE than other formulas.

[Laboratory diagnostics of lipid metabolism disorders]

Clinically, disorders of lipid metabolism often remain without symptoms. Typical skin lesions, however, can be indicative. Secondary hyperlipoproteinemias (HLP) are more common than primary hyperlipoproteinemias; they can (partially) be improved by treating the underlying disease. Basic diagnostics consist of the determination of cholesterol, triglycerides, LDL cholesterol and HDL cholesterol. To exclude secondary HLP, glucose, HbA1C, TSH, transaminases, creatinine, urea, protein and protein in the urine are useful. Since virtually all routine methods for LDL-C are biased by high triglycerides, lipoprotein electrophoresis is indicated for triglycerides above 400 mg/dl (4.7 mmol/l). Primary HLPs have known or yet unknown genetic causes. Primary hyperlipidemias should be taken into consideration especially in young patients with an LDL cholesterol concentration are above 190 mg/dl (4.9 mmol/l) and/or triglycerides above 400 mg/dl (10 mmol/l) and secondary HLP (obesity, alcohol, diabetes mellitus, kidney disease) is excluded. The basic diagnostics is meaningfully extended by the measurement of lipoprotein (a) (Lp(a)). It is indicated in moderate and high risk of vascular disease, progression of atherosclerosis in "well-controlled" LDL cholesterol, familial clustering of atherosclerosis or high Lp(a), evidence for elevated Lp(a) coming from lipoprotein electrophoresis, aortic stenosis and in patients in whom statins have a poor effect. Genetic diagnostics needs to be considered if primary HLP is suspected. It is most frequently conducted for suspected familial hypercholesterolemia and has already been recommended in guidelines.

Concordance/discordance between serum apolipoprotein B, low density lipoprotein cholesterol and non-high density lipoprotein cholesterol in NATPOL 2011 participants - An epidemiological perspective

BACKGROUND

The study compared the distribution of serum LDL-C, non-HDL-C, and apolipoprotein B (apoB) among participants of the NATPOL 2011 survey and analysed concordance/discordance of results in the context of the risk for atherosclerotic cardiovascular disease (ASCVD).

METHODS

Serum levels of apoB, LDL-C, non-HDL-C and small dense LDL-C were measured/calculated in 2067-2098 survey participants. The results were compared between women and men, age groups and in relation to body mass index (BMI), fasting glucose and TG levels, and the presence of CVD. Percentile distribution of lipid levels and concordance/discordance analysis were based on medians and ESC/EAS 2019 target thresholds for ASCVD risk and on comparison of measured apoB levels and levels calculated from linear regression equations with serum LDL- C and non-HDL-C as independent variables.

RESULTS

Serum apoB, LDL-C and non-HDL-C were similarly related to sex, age, BMI, visceral obesity, cardiovascular disease, and fasting glucose and triglyceride levels. Serum apoB, LDL-C and non-HDL-C very high- and moderate- target thresholds were exceeded in 83%, 99% and 96.9% and in 41%, 75% and 63.7% of subjects, respectively. The incidence of the discordances between the results depended on the dividing values used and ranged from 0.2% to 45.2% of the respondents. Subjects with high apoB / low LDL-C/non-HDL-C discordance had features of metabolic syndrome.

CONCLUSIONS

Diagnostic discordances between apoB and LDL-C/non-HDL-C indicate limitations of serum LDL-C/non-HDL-C in ASCVD risk management. Due to the high apoB/low LDL-C/non-HDL-C discordance, obese/metabolic syndrome patients may benefit from replacing LDL-C/non-HDL-C by apoB in ASCVD risk assessment and lipid-lowering therapy.

Reducing Lipid Panel Error Allowances to Improve the Accuracy of Cardiovascular Risk Stratification

BACKGROUND

The standard lipid panel forms the backbone of atherosclerotic cardiovascular disease risk assessment. Suboptimal analytical performance, along with biological variability, could lead to erroneous risk assessment and management decisions. The current National Cholesterol Education Program (NCEP) performance recommendations have remained unchanged for almost 3 decades despite improvements in assay technology. We investigated the potential extent of risk misclassification when the current recommendations are met and explored the impact of improving analytical performance goals.

METHODS

We extracted lipid panel data for 8506 individuals from the NHANES database and used these to classify subjects into 4 risk groups as recommended by the 2018 US Multisociety guidelines. Analytical bias and imprecision, at the allowable limits, as well as biological variability, were introduced to the measured values to determine the impact on misclassification. Bias and imprecision were systematically reduced to determine the degree of improvement that may be achieved.

RESULTS

Using the current performance recommendations, up to 10% of individuals were misclassified into a different risk group. Improving proportional bias by 1%, and fixing imprecision to 3% across all assays reduced misclassifications by up to 10%. The effect of biological variability can be reduced by taking the average of serial sample measurements.

CONCLUSIONS

The current NCEP recommendations for analytical performance of lipid panel assays allow for an unacceptable degree of misclassification, leading to possible mismanagement of cardiovascular disease risk. Iteratively reducing allowable error can improve this.

Factors to consider with estimated low-density lipoprotein cholesterol using the new Sampson/NIH equation

INTRODUCTION

The most commonly utilized method for determining low-density lipoprotein cholesterol (LDLc) is by Friedewald estimation (FeLDLc). A new approach to better estimate LDLc has been proposed by Sampson et al. 2020, known as the Sampson/National Institutes of Health (NIH) estimation of LDLc (NeLDLc), to overcome the limitations of FeLDLc. Non-high-density lipoprotein-cholesterol (Non-HDLc), has equivalent cut-offs to LDLc, established by the 2021 Canadian Cardiovascular Society (CCS) guideline. We hypothesized that NeLDLc remains an inadequate substitute at high triglyceride levels when compared to Non-HDLc.

METHODS

A retrospective analysis of 120,959 lipid profiles (47085 patients) spanning five years across a large academic medical center was utilized for comparison of NeLDLc and FeLDLc relative to Non-HDLc as a function of triglyceride content. Regression and concordance between calculated methods were determined at various triglyceride levels to determine optimal utilization of NeLDLc.

RESULTS

NeLDLc is generally more correlated and has greater concordance than FeLDLc with Non-HDLc. NeLDLc with increasing triglycerides can produce negatively erroneous results, even with triglycerides < 4.52 mmol/L (400 mg/dL). The largest variation of NeLDLc results is notable at < 0.5 mmol/L (19 mg/dL). Currently, the 2021 CCS guideline recommends reliance on Non-HDLc when triglycerides are > 1.5 mmol/L (133 mg/dL). With the use of NeLDLc, this triglyceride cut-off can be increased to 1.7 mmol/L(150 mg/dL), making it consistent with the hypertriglyceridemia flagging limit.

CONCLUSION

NeLDLc offers increased concordance and correlation to Non-HDLc when compared to FeLDLc. However, caution is warranted when triglycerides are > 4.5 mmol/L and when NeLDLc results are < 0.5 mmol/L. Adopting NeLDLc enables flagging at 1.7 mmol/L (vs. 1.5 mmol/L) of triglycerides to suggest reliance on Non-HDLc while simultaneoulsly indicating hypertriglyceridemia.

Use of Apolipoprotein B in the Era of Precision Medicine: Time for a Paradigm Change?

Atherosclerotic cardiovascular disease (ASCVD) remains the leading cause of death worldwide and the risk of a major cardiovascular event is highest among those with established disease. Ongoing management of these patients relies on the accurate assessment of their response to any prescribed therapy, and their residual risk, in order to optimize treatment. Recent international guidelines and position statements concur that the plasma concentration of apolipoprotein B (apoB) is the most accurate measure of lipoprotein associated ASCVD risk. This is especially true for the growing number of individuals with diabetes, obesity, or the metabolic syndrome, and those on statin therapy. Most guidelines, however, continue to promote LDL-C as the primary risk marker due to uncertainty as to whether the greater accuracy of apoB is sufficient to warrant a paradigm shift. Recommendations regarding apoB measurement vary, and the information provided on how to interpret apoB results is sometimes insufficient, particularly for non-lipid specialists. Misinformation regarding the reliability of the assays is also frequently repeated despite its equivalent or better standardization than many other diagnostic assays. Thus, demand for apoB testing is relatively low, which means there is little incentive to increase its availability or reduce its cost. In this review, we examine the results of recent clinical outcomes studies and meta-analyses on the relative values of apoB, LDL-C, and non-HDL-C as markers of ASCVD risk. Although there is seemingly minimal difference among these markers when only population-based metrics are considered, it is evident from our analysis that, from a personalized or precision medicine standpoint, many individuals would benefit, at a negligible total cost, if apoB measurement were better integrated into the diagnosis and treatment of ASCVD.

Apolipoprotein B compared with low-density lipoprotein cholesterol in the atherosclerotic cardiovascular diseases risk assessment

The subendothelial retention of apolipoprotein B (apoB)-containing lipoproteins is a critical step in the initiation of pro-atherosclerotic processes. Recent genetic and clinical evidence strongly supports the concept that the lipid content of the particles is secondary to the number of circulating atherogenic particles that are trapped within the arterial lumen. Since each low-density lipoproteins (LDL) particle contains one apoB molecule, as do intermediate density lipoprotein (IDL) and very low-density lipoprotein (VLDL) particles, apoB level represents the total number of atherogenic lipoproteins, which is independent of particle density, and not affected by the heterogeneity of particle cholesterol content (clinically evaluated by LDL-cholesterol level). From this perspective, apoB is proposed as a better proxy to LDL-cholesterol for assessing atherosclerotic cardiovascular disease risk, especially in specific subgroups of patients, including subjects with diabetes mellitus, with multiple cardiometabolic risk factors (obesity, metabolic syndrome, insulin resistance, and hypertension) and with high triglyceride levels and very low LDL-cholesterol levels. Therefore, given the causal role of LDL-cholesterol in atherosclerotic cardiovascular disease (ASCVD) development, routine measurement of both LDL-cholesterol and apoB is of utmost importance to properly estimate global cardiovascular risk and to determine the 'residual' risk of ASCVD in patients receiving therapy, as well as to monitor therapeutic effectiveness.

Remnant cholesterol, low-density lipoprotein cholesterol, and incident cardiovascular disease among Koreans: a national population-based study

AIMS

The synergistic association of remnant cholesterol (remnant-C) and low-density lipoprotein cholesterol (LDL-C) levels with incident cardiovascular disease (CVD) in various subgroups of Koreans was investigated.

METHODS AND RESULTS

Using the national health insurance data, we included subjects aged between 40 and 70 years without a history of CVD and at least two health screenings between 2009 and 2011. The subjects were divided into four groups by LDL-C and remnant-C levels. The primary outcome was CVD, which occurred between 2014 and 2017. Among 3 686 034 (45.6% women) subjects, 144 004 cardiovascular events occurred. Individuals in both high LDL-C and high remnant-C [hazard ratio (HR) 1.266, 95% confidence interval (CI) 1.243-1.289; 7.9%], high LDL-C only (HR 1.098, 95% CI 1.083-1.113; 21.2%), and high remnant-C only groups (HR 1.102, 95% CI 1.087-1.118; 19.1%) had higher risks of CVD than those in the reference group (LDL-C < 3.4 mmol/L and remnant-C < 0.8 mmol/L; 51.8%). A continuous and linear increase in CVD risk was found in those with higher remnant-C levels after adjustment for several confounders, including LDL-C levels. The association of remnant-C ≥ 0.8 mmol/L with an increased CVD risk was consistent across various strata.

CONCLUSIONS

Combined high remnant-C and LDL-C levels confer a higher CVD risk than that individually. Elevated remnant-C values independent of LDL-C levels were associated with a risk of incident CVD. Remnant cholesterol levels in addition to LDL-C levels are important considerations in risk stratification for the primary prevention of CVD.

Standardization of Apolipoprotein B, LDL-Cholesterol, and Non-HDL-Cholesterol

Concern continues about whether the measurement of apolipoprotein B (apoB) is adequately standardized, and therefore, whether apoB should be applied widely in clinical care. This concern is misplaced. Our objective is to explain why and what the term "standardization" means. To produce clinically valid results, a test must accurately, precisely, and selectively measure the marker of interest. That is, it must be standardized. Accuracy refers to how closely the result obtained with 1 method corresponds to the result obtained with the standard method, precision to how reproducible the result is on repeated testing, and selectivity to how susceptible the method is to error by inclusion of other classes of lipoprotein particles. Multiple expert groups have determined that the measurement of apoB is adequately standardized for clinical care, and that apoB can be measured inexpensively, using widely available automated methods, more accurately, precisely, and selectively than low-density lipoprotein cholesterol or non-high-density lipoprotein cholesterol. ApoB is a standard superior to low-density lipoprotein cholesterol and high-density lipoprotein cholesterol because it is a defined molecule, whereas the cholesterol markers are the mass of cholesterol within lipoprotein particles defined by their density, not by their molecular structure. Nevertheless, the standardization of apoB is being further improved by the application of mass spectrophotometric methods, whereas the limitations in the standardization and, therefore, the accurate, precise, and selective measurement of low-density lipoprotein cholesterol and high-density lipoprotein cholesterol are unlikely to be overcome. We submit that greater accuracy, precision, and selectivity in measurement is a decisive advantage for apoB in the modern era of intensive lipid-lowering therapies.

Lipoprotein(a) and risk of cognitive impairment in Black and White Americans: the Reasons for Geographic and Racial Differences in Stroke cohort

Background

Cognitive impairment has a substantial vascular etiology. Higher lipoprotein(a) [Lp(a)] is associated with cardiovascular disease risk, but its association with cognitive function is uncertain. We hypothesized that Lp(a) is a risk factor for cognitive impairment, a relationship that would be modified by race and sex.

Objectives

To study the association of Lp(a) with cognitive impairment in a biracial cohort.

Methods

The Reasons for Geographic and Racial Differences in Stroke (REGARDS) study recruited 30,239 Black and White Americans aged >45 years from 2003 to 2007. After 3.4 years, among participants with normal baseline cognition, baseline Lp(a) was measured in 434 cases of incident cognitive impairment and 557 controls. Cognitive impairment was defined as scores below the sixth percentile based on age, sex, race, and education norms on 2 or 3 components of a 3-test battery administered every 2 years.

Results

Median Lp(a) was higher in Black than in White individuals. Among Black participants, the adjusted odds ratio (OR) of cognitive impairment per SD higher increment Lp(a) was 1.39 (95% CI: 1.05, 1.84). The OR in White participants was 1.03 (95% CI: 0.87, 1.21; P for race difference = .03). The relationship of Lp(a) with cognitive trajectory differed by sex and race. Elevated Lp(a) was associated with worse baseline memory in Black men and a steeper trajectory of verbal fluency decline in Black men than in White men and women.

Conclusion

Higher Lp(a) was associated with increased risk of cognitive impairment in Black but not White individuals. Future studies should evaluate the biological and social mechanisms through which race and Lp(a) interact to increase risk of cognitive impairment.

Comparative performance of equations to estimate low-density lipoprotein cholesterol levels and cardiovascular disease incidence: The ATTICA study (2002-2022)

Accurate estimation of low-density lipoprotein cholesterol (LDL-C) is important for monitoring cardiovascular disease (CVD) risk and guiding lipid-lowering therapy. This study aimed to evaluate the magnitude of discordance of LDL-C levels calculated by different equations and its effect on CVD incidence. The study sample consisted of 2354 CVD-free individuals (49% males, mean age 45 ± 14 years); 1600 were re-evaluated at 10 years and 1570 at 20 years. LDL-C was estimated using the Friedewald, Martin/Hopkins, and Sampson equations. Participants were categorized as discordant if estimated LDL-C was below the CVD-risk specific cut-off for one equation and equal/above for its comparator. The Friedewald and Martin/Hopkins equations presented a similar performance in estimating LDL-C; however, both yielded lower values compared to the Sampson. In all pairwise comparisons, differences were more pronounced at lower LDL-C levels, while the Friedewald equation significantly underestimated LDL-C in hypertriglyceridemic participants. Discordance was evident in 11% of the study population, and more specifically 6%, 22%, and 20% for Friedewald versus Martin/Hopkins, Friedewald versus Sampson and Martin/Hopkins versus Sampson equations, respectively. Among discordant participants, median (1st, 3rd quartile) difference in LDL-C was -4.35 (-10.1, 1.95), -10.6 (-12.3, -9.53) and -11.3 (-11.9, -10.6) mg/dL for Friedewald versus Martin/Hopkins, Friedewald versus Sampson and Martin/Hopkins versus Sampson equations, respectively. The 10- and 20-year CVD survival model that included LDL-C values of the Martin-Hopkins equation outperformed the predictive ability of those based on the Friedewald or Sampson equations. Significant differences in estimated LDL-C exist among equations, which may result in LDL-C underestimation and undertreatment.

Remnant cholesterol, vascular risk, and prevention of atherosclerosis

In patients who have achieved optimal LDL-C control, there remains a residual risk of atherothrombotic cardiovascular disease (ACVD) related to alterations in lipid metabolism, where alterations in triglyceride-rich lipoproteins and the cholesterol they contain, called remnant cholesterol, play a major role. Remnant cholesterol has an association with residual risk of ACVD that is independent of LDL-C and has been demonstrated in epidemiological and Mendelian randomisation studies, and in analyses of clinical trials of lipid-lowering drugs. Remnant triglyceride-rich lipoproteins particles are highly atherogenic, due to their ability to enter and be retained in the arterial wall, their high cholesterol content, and their ability to generate "foam cells" and an inflammatory response. Assessment of remnant cholesterol may provide information on residual risk of ACVD beyond the information provided by LDL-C, Non-HDL-C, and apoB, particularly in individuals with hypertriglyceridaemia, type 2 diabetes, or metabolic syndrome. In the REDUCE-IT study, icosapent ethyl was shown to have a preventive effect against ACVD in very high cardiovascular risk patients with hypertriglyceridaemia treated with statins and target LDL-C. New lipid-lowering drugs will help to define efficacy and criteria in the treatment of excess remnant cholesterol and hypertriglyceridaemia in the prevention of ACVD.

Comparison of existing methods of low-density lipoprotein cholesterol estimation in patients with type 2 diabetes mellitus

Introduction

Elevated low-density lipoprotein cholesterol (LDL-C) is an important risk factor for atherosclerotic cardiovascular disease (ASCVD). Direct LDL-C measurement is not widely performed. LDL-C is routinely calculated using the Friedewald equation (FLDL), which is inaccurate at high triglyceride (TG) or low LDL-C levels. We aimed to compare this routine method with other estimation methods in patients with type 2 diabetes mellitus (T2DM), who typically have elevated TG levels and ASCVD risk.

Method

We performed a retrospective cohort study on T2DM patients from a multi-institutional diabetes registry in Singapore from 2013 to 2020. LDL-C values estimated by the equations: FLDL, Martin/Hopkins (MLDL) and Sampson (SLDL) were compared using measures of agreement and correlation. Subgroup analysis comparing estimated LDL-C with directly measured LDL-C (DLDL) was conducted in patients from a single institution. Estimated LDL-C was considered discordant if LDL-C was <1.8mmol/L for the index equation and ≥1.8mmol/L for the comparator.

Results

A total of 154,877 patients were included in the final analysis, and 11,475 patients in the subgroup analysis. All 3 equations demonstrated strong overall correlation and goodness-of-fit. Discordance was 4.21% for FLDL-SLDL and 6.55% for FLDL-MLDL. In the subgroup analysis, discordance was 21.57% for DLDL-FLDL, 17.31% for DLDL-SLDL and 14.44% for DLDL-MLDL. All discordance rates increased at TG levels >4.5mmol/L.

Conclusion

We demonstrated strong correlations between newer methods of LDL-C estimation, FLDL, and DLDL. At higher TG concentrations, no equation performed well. The Martin/Hopkins equation had the least discordance with DLDL, and may minimise misclassification compared with the FLDL and SLDL.

The role of atherogenic lipoproteins in diabetes: Molecular aspects and clinical significance

Dyslipidaemia plays a prominent role in the genesis of atherosclerotic plaque and the increased cardiovascular risk in diabetes. Macrophages readily take up atherogenic lipoproteins, transforming into foam cells and amplifying vascular damage in the presence of endothelial dysfunction. We discuss the importance of distinct lipoprotein subclasses in atherogenic diabetic dyslipidaemia as well as the effects of novel anti-diabetic agents on lipoprotein fractions and ultimately on cardiovascular risk prevention. In patients with diabetes, lipid abnormalities should be aggressively identified and treated in conjunction with therapeutical agents used to prevent cardiovascular disease. The use of drugs that improve diabetic dyslipidaemia plays a prominent role in conferring cardiovascular benefit in individuals with diabetes.

The healthful plant-based diet index as a tool for obesity prevention-The healthy lifestyle community program cohort 3 study

Background

World-wide the prevalence of obesity is high, and promoting a shift toward more healthful and more plant-based dietary patterns appears to be one promising strategy to address this issue. A dietary score to assess adherence to a healthy plant-based diet is the healthful plant-based diet index. While there is evidence from cohort studies that an increased healthful plant-based diet index is associated with improved risk markers, evidence from intervention studies is still lacking.

Methods

A lifestyle intervention was conducted with mostly middle-aged and elderly participants from the general population (n = 115). The intervention consisted of a 16-month lifestyle program focusing on a healthy plant-based diet, physical activity, stress management, and community support.

Results

After 10 weeks, significant improvements were seen in dietary quality, body weight, body mass index, waist circumference, total cholesterol, measured and calculated low-density lipoprotein (LDL) cholesterol, oxidized LDL particles, non-high-density lipoprotein cholesterol, remnant cholesterol, glucose, insulin, blood pressure, and pulse pressure. After 16 months, significant decreases were seen in body weight (-1.8 kg), body mass index (-0.6 kg/m2), and measured LDL cholesterol (-12 mg/dl). Increases in the healthful plant-based diet index were associated with risk marker improvements.

Conclusions

The recommendation of moving toward a plant-based diet appears acceptable and actionable and may improve body weight. The healthful plant-based diet index can be a useful parameter for intervention studies.

Exploring the underlying mechanisms linking adiposity and cardiovascular disease: A prospective cohort study of 404,332 UK Biobank participants

BACKGROUND AND AIMS

Obesity is causally associated with multiple cardiovascular outcomes but effective population measure to control obesity is limited. This study aims to decipher to which extent excess atherosclerotic cardiovascular diseases (ASCVD) and heart failure (HF) risk due to obesity can be explained by conventional risk factors.

METHODS

This is a prospective cohort study of 404,332 White UK Biobank participants. Participants with prior CVDs or other chronic diseases at baseline, or body mass index (BMI) <18·5 kg/m2 were excluded. Data were collected at the baseline assessment between 2006 and 2010. Linkage to death registrations and hospital admission records was used to ascertain ASCVD and HF outcomes up to late 2021. Obesity was defined as BMI ≥30 kg/m2. Candidate mediators included lipids, blood pressure, glycated haemoglobin (HbA1c), and liver and kidney function markers, which were chosen based on clinical trials and Mendelian randomisation studies. Cox proportional hazard models were used to estimate hazard ratios (HR) and their 95% confidence intervals (CIs). Mediation analysis based on g-formula was used to separately estimate the relative importance of mediators for ASCVD and HF.

RESULTS

Compared with people without obesity, obese people had an increased risk of ASCVD (HR 1.30, 95% CI 1.26-1.35) and HF (HR 2.04, 95% CI 1.96-2.13) after adjusting for sociodemographic and lifestyle factors and medications for cholesterol, blood pressure and insulin. The strongest mediators for ASCVD were renal function (eGFR: mediation proportion: 44.6%), blood pressure (SBP: 24.4%; DBP: 31.1%), triglycerides (19.6%), and hyperglycaemia (HbA1c 18.9%). These mediators collectively explained more excess risk of ASCVD than that of HF.

CONCLUSIONS

Interventions that help obese individuals to maintain healthy lipid concentrations, blood pressure, glycaemic control and kidney function could potentially alleviate a sizable proportion of the ASCVD burden. However, HF burden could not be meaningfully reduced without weight management.

Cholesterol Remnants, Triglyceride-Rich Lipoproteins and Cardiovascular Risk

Randomized clinical trials with statins and other lipid-lowering drugs have shown the presence of a "residual cardiovascular risk" in those treated to "target" for LDL-cholesterol. This risk is mainly associated to lipid components other than LDL and in particular to remnant cholesterol (RC) and to lipoproteins rich in triglycerides in fasting and non-fasting conditions. During fasting, RCs correspond to the cholesterol content of the VLDL and their partially depleted triglyceride remnant containing apoB-100. Conversely, in non-fasting conditions, RCs include also cholesterol present in chylomicrons containing apoB-48. Therefore, RCs refer to total plasma cholesterol minus HDL-cholesterol and LDL-cholesterol, that is, all the cholesterol present in the VLDL, chylomicrons and in their remnants. A large body of experimental and clinical data suggests a major role of RCs in the development of atherosclerosis. In fact, RCs easily pass the arterial wall and bind to the connective matrix stimulating the progression of smooth muscle cells and the proliferation of resident macrophages. RCs are a causal risk factor for cardiovascular events. Fasting and non-fasting RCs are equivalent for predicting vascular events. Further studies on drugs effect on RC levels and clinical trials to evaluate the efficacy of RC reduction on cardiovascular events are needed.

Low-density lipoprotein cholesterol and non-high-density lipoprotein cholesterol measurement in Familial Dysbetalipoproteinemia

AIM

To compare LDL-C concentrations using the Friedewald formula, the Martin-Hopkins formula, a direct assay and polyacrylamide gradient gel electrophoresis (PGGE) to the reference standard density gradient ultracentrifugation in patients with Familial Dysbetalipoproteinemia (FD) patients. We also compared non-HDL-cholesterol concentrations by two methods.

METHODS

For this study data from 28 patients with genetically confirmed FD from the placebo arm of the EVOLVE-FD trial were used. Four different methods for determining LDL-C were compared with ultracentrifugation. Non-HDL-C was measured with standard assays and compared to ultracentrifugation. Correlation coefficients and Bland-Altman plots were used to compare the methods.

RESULTS

Mean age of the 28 FD patients was 62 ± 9 years, 43 % were female and 93 % had an ɛ2ɛ2 genotype. LDL-C determined by Friedewald (R² = 0.62, p <0.01), Martin-Hopkins (R² = 0.50, p = 0.01) and the direct assay (R² = 0.41, p = 0.03) correlated with density gradient ultracentrifugation. However, Bland-Altman plots showed considerable over- or underestimation by the four methods compared to ultracentrifugation. Non-HDL-C showed good correlation and agreement.

CONCLUSION

In patients with FD, all four methods investigated over- or underestimated LDL-C concentrations compared with ultracentrifugation. In contrast, standard non-HDL-C assays performed well, emphasizing the use of non-HDL-C in patients with FD.

Nomograms Based on Non-High-Density Lipoprotein to Predict Outcomes in Patients with Prior Coronary Artery Bypass Grafting with Acute Coronary Syndrome: A Single-Center Retrospective Study

Introduction

Non-high-density-lipoprotein cholesterol (non-HDL-C) is a secondary therapeutic target in cardiovascular diseases and is used for residual risk assessment in patients with coronary artery syndrome (ACS). This study was designed to determine the association between non-HDL-C in patients with prior coronary artery bypass graft (CABG) with ACS and clinical outcomes.

Methods

We retrospectively analyzed 468 patients with prior CABG with ACS and categorized them into two groups based on the median non-HDL-C level. The primary endpoints were major adverse cardiovascular events (MACEs), including cardiovascular death and recurrent myocardial infarction. Kaplan-Meier curves, Cox proportional-hazard regressions, and restricted cubic splines were used to determine the association between non-HDL-C and MACEs. The discrimination and reclassification of the nomogram based on non-HDL-C were assessed using time-dependent receiver operating characteristic (ROC) curves and net reclassification improvement (NRI).

Results

During the average follow-up time of 744.5 days, non-HDL-C was independently associated with the occurrence of MACEs (hazard ratio [HR] = 5.01, 95% confidence interval [CI] = 1.65-15.24; p = 0.005) after adjusting for other lipid parameters. The spline curves indicated a linear relationship between non-HDL-C and MACEs (p-nonlinear: 0.863). The time-dependent areas under the ROC curves of prior-CABG-ACS nomograms containing non-HDL regarding MACEs in two consecutive years were 91.7 (95% CI: 85.5-97.9) and 91.5 (95% CI: 87.3-95.7), respectively. The NRI analysis indicated that the prior-CABG-ACS model improved the reclassification ability for 1- and 2-year MACEs (22.4% and 7%, p < 0.05, respectively).

Discussion

Non-HDL is independently associated with the risk of MACEs in patients with prior CABG with ACS. The prior-CABG-ACS nomogram based on non-HDL-C and five convenient variables generates valid and stable predictions of MACE occurrence.

A Translational Tool to Facilitate Use of Apolipoprotein B for Clinical Decision-Making

BACKGROUND

Despite recent large-scale discordance studies showing definitively that atherosclerotic cardiovascular disease (ASCVD) risk correlates better with apolipoprotein B (apoB) than with low-density lipoprotein cholesterol (LDL-C), the latter remains the recommended metric for guiding lipid-lowering treatment decisions in the United States. A major barrier to change, in this regard, is the lack of guideline-recommended apoB treatment targets. We developed a simple method to "translate" apoB values into population-equivalent LDL-C units, allowing apoB-based treatment decisions to be made using LDL-C targets.

METHODS

Sequentially collected, population-based samples underwent standard lipid panel analysis and apoB testing by immunoassay. Those with triglycerides greater than 1000 mg/dl were excluded, leaving a study cohort of 15 153 individuals.

RESULTS

Linear regression of calculated LDL-C values against percentile-equivalent apoB values yielded an equation to convert apoB into percentile-equivalent LDL-C units: [LDL-C equivalents = 1.38(apoB) - 29] (R2 = 0.999). The extent of discordance between LDL-C and apoB was examined in subgroups with similar LDL-C, ranging from very low (55-70 mg/dL) to very high (175-190 mg/dL). Among individuals with very low LDL-C, 40% had discordantly higher apoB, indicating higher ASCVD risk. Of those with very high LDL-C, 49% had discordantly lower apoB. Across the range, a minority of patients (25%-40%) had concordant levels of apoB, confirming that discordance between these biomarkers is highly prevalent. Similar results were found in discordance analysis between apoB and non-high-density lipoprotein cholesterol (HDL-C).

CONCLUSIONS

Providing visibility to discrepancies among LDL-C, non-HDL-C, and apoB should help to facilitate more rapid and widespread adoption of apoB for managing ASCVD risk.

The Role of Advanced Glycation End Products on Dyslipidemia

Disorders of lipoprotein metabolism and glucose homeostasis are common consequences of insulin resistance and usually co-segregate in patients with metabolic syndrome and type 2 diabetes mellitus (DM). Insulin-resistant subjects are characterized by atherogenic dyslipidemia, a specific lipid pattern which includes hypertriglyceridemia, reduced high-density lipoprotein cholesterol level, and increased proportion of small, dense low-density lipoprotein (LDL). Chronic hyperglycemia favors the processes of non-enzymatic glycation, leading to the increased production of advanced glycation end products (AGEs). Apart from direct harmful effects, AGEs are also potent inducers of oxidative stress and inflammation. In addition, increased AGEs' production may induce further qualitative modifications of small, dense LDL particles, converting them to glycated LDLs. These particles are even more atherogenic and may confer an increased cardiovascular risk. In this narrative review, we summarize the available evidence of the pathophysiological role and clinical importance of circulating AGEs and glycated LDLs in patients with dyslipidemia, particularly those with DM and related complications. In addition, we discuss recent advances and the issues that should be improved regarding laboratory assessment of AGEs and glycated LDLs, as well as the possibilities for their therapeutic modulation.

Lipids in Atherosclerosis: Pathophysiology and the Role of Calculated Lipid Indices in Assessing Cardiovascular Risk in Patients with Hyperlipidemia

The role of lipids is essential in any phase of the atherosclerotic process, which is considered a chronic lipid-related and inflammatory condition. The traditional lipid profile (including the evaluation of total cholesterol, triglycerides, high-density lipoprotein, and low-density lipoprotein) is a well-established tool to assess the risk of atherosclerosis and as such has been widely used as a pillar of cardiovascular disease prevention and as a target of pharmacological treatments in clinical practice over the last decades. However, other non-traditional lipids have emerged as possible alternative predictors of cardiometabolic risk in addition to traditional single or panel lipids, as they better reflect the overall interaction between lipid/lipoprotein fractions. Therefore, this review deals with the lipid involvement characterizing the pathophysiology of atherosclerosis, discussing some recently proposed non-traditional lipid indices and, in the light of available knowledge, their actual potential as new additive tools to better stratify cardiovascular risk in patients with hyperlipidemia as well as possible therapeutic targets in the clinical practice.

Lipoprotein (a) and long-term outcome in patients with peripheral artery disease undergoing revascularization

BACKGROUND AND AIMS

Despite low LDL-C goals, the residual risk for further cardiovascular (CV) events in patients with peripheral artery disease (PAD) remains high. Lipoprotein (a) (Lp(a)) is a known risk factor for PAD incidence, but little is known regarding the outcome in patients with symptomatic PAD. Thus, this study investigates Lp(a) and CV mortality in PAD after endovascular repair.

METHODS

A total of 1222 patients with PAD in two cohorts according to Lp(a) assay in nmol/L (n = 964, Lip-LEAD-A) or mg/dl (n = 258, Lip-LEAD-B) were followed up for 4.3 (IQR 3.0-5.6) or 7.6 (IQR 3.2-8.1) years. Lp(a) was measured before endovascular repair for either intermittent claudication (IC) or critical limb ischemia (CLI). Outcome information was obtained from the federal death registry.

RESULTS

In Lip-LEAD-A, 141 CV-deaths occurred (annual calculated CV-death rate 3.4%), whereas 64 CV-deaths were registered in Lip-LEAD-B (annual calculated CV-death rate 3.3%). After adjustment for traditional CV risk factors Lp(a) was neither associated with outcome in Lip-LEAD-A (highest tertile HR 1.47, 95%CI [0.96-2.24]) nor in Lip-LEAD-B (highest tertile HR 1.34 [0.70-2.58]). Subanalyses for IC (HR 1.37 [0.74-2.55]; HR 1.10 [0.44-2.80], CLI (HR 1.55 [0.86-2.80], HR 3.01 [0.99-9.10]), or concomitant coronary artery disease (CAD; HR 1.34 [0.71-2.54]; HR 1.21 [0.46-3.17]) failed to show a significant association between Lp(a) and CV-mortality.

CONCLUSIONS

In this large-scale cohort of symptomatic PAD no association of elevated Lp(a) with CV mortality was found over a median observation period of 5 years. Thus, an even longer study including asymptomatic patients is warranted.

Exploring the Novelty in Lipid Profiling of Patients: A Non-fasting Approach from Eastern India

Objective To date, no reference interval is available for lipid profile, including total cholesterol (TC), triglycerides (TGs), high-density lipoprotein (HDL), or low-density lipoprotein (LDL)-cholesterol, etc., in a non-fasting state. Hence, the study was taken up with the objective of exploring the possibility of establishing a reference interval for non-fasting lipid profile consisting of serum TC, TG, LDL, HDL, and very low-density lipoprotein (VLDL) cholesterol.

Materials and Methods A total of 1,350 apparently healthy subjects, including 636 healthy men and 714 healthy women of 18 years and beyond of age, were enrolled in the study. Reference individuals were recruited using cluster sampling method from various villages and semi-urban regions irrespective of their sex, religion, socioeconomic status, or any other demographic profile, and samples were analyzed in Beckman Coulter AU480 analyzer.

Results The mean age of 1,350 participants was 38.23 ± 15.94 years. We found that all the test parameters require a different reference interval than the established fasting reference range, except for HDL cholesterol in females. The data were subdivided into subjects below 40 years, between 40 and 60 years, and older than 60 years of age. All five parameters in the lipid profile were individually analyzed and were compared age group-wise and gender-wise with the total study population. Significant differences in the various dataset were found.

Conclusion A shift toward non-fasting lipid interval measurement is, thus, a piece of evidence-driven mechanism. Even from a patient's perspective, it sets in ease and convenience in lipid-profile testing, subsequently leading to a more compliant cardiovascular management and monitoring.

Comparison of Estimated LDL Cholesterol Equations with Direct Measurement in Patients with Angiographically Confirmed Coronary Artery Disease

Background and aims: Our goals in the study were to (1) quantify the discordance in LDL-C levels between equations (the Friedewald, Sampson, and Martin/Hopkins equations) and compare them with direct LDL-C (dLDL-C); and (2) explore the proportion of misclassified patients by calculated LDL-C using these three different equations. Methods: A total of 30,349 consecutive patients with angiographically confirmed coronary artery disease (CAD) were prospectively enrolled. Concordance was defined as if the LDL-C was <1.8 mmol/L with each pairwise comparison of LDL-C equations. Estimated LDL-C that fell into the same category as dLDL-C at the following levels: <1.4, 1.4 to 1.7, 1.8 to 2.5, 2.6 to 2.9, and ≥3.0 mmol/L was considered to have been correctly categorized. Results: The concordance was 96.3% (Sampson vs. Martin/Hopkins), 95.0% (Friedewald vs. Sampson), and 91.4% (Friedewald vs. Martin/Hopkins), respectively. This proportion fell to 82.4% in those with hypertriglyceridemia (TG ≥ 1.7 mmol/L). With an accurate classification rate of 73.6%, the Martin/Hopkins equation outperformed the Sampson equation (69.5%) and the Friedewald equation (59.3%) by a wide margin. Conclusions: Comparing it to the validated Martin/Hopkins equation, the Friedewald equation produced the lowest levels of LDL-C, followed by the Sampson equation. In the classification of LDL-C, the Martin/Hopkins equation has also been shown to be more accurate. There is a significant difference between the equations and the direct measurement method, which may lead to overtreatment or undertreatment.

Integrated guidance to enhance the care of children and adolescents with familial hypercholesterolaemia: Practical advice for the community clinician

Familial hypercholesterolaemia (FH) is a highly penetrant monogenic disorder present from birth that markedly elevates plasma low-density lipoprotein (LDL)-cholesterol (LDL-C) concentration and, if untreated, leads to premature atherosclerosis and coronary artery disease (CAD). At a prevalence of 1:250 individuals, with over 90% undiagnosed, recent estimates suggest that there are approximately 22 000 children and adolescents with FH in Australia and New Zealand. However, the overwhelming majority remain undetected and inadequately treated until adulthood or after their first cardiac event. The guidance in this paper aims to increase awareness about paediatric FH and provide practical advice for the diagnosis and management of FH in children and adolescents. Recommendations are given on the detection, diagnosis, assessment and management of FH in children and adolescents. Recommendations are also made on genetic testing, including counselling and the potential for universal screening programmes. Practical guidance on management includes treatment of non-cholesterol risk factors, and safe and appropriate use of LDL-C lowering therapies, including statins, ezetimibe, PCSK9 inhibitors and lipoprotein apheresis. Models of care for FH need to be adapted to local and regional health care needs and available resources. Targeting the detection of FH as a priority in children and young adults has the potential to alter the natural history of atherosclerotic cardiovascular disease and recognise the promise of early detection for improving long-term health outcomes. A comprehensive implementation strategy, informed by further research, including assessments of cost-benefit, will be required to ensure that this new guidance benefits all families with or at risk of FH.