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• It is acceptable to screen with nonfasting lipids. • It is recommended to follow up abnormal results with fasting levels. • Non-HDL cholesterol levels can effectively guide ASCVD prevention. • Advanced lipoprotein tests may guide therapeutic decisions in select patients. • Better harmonization of advanced lipid measurement methods is needed. • Recommendations for lipids in clinical care. Lipoprotein measurements are pivotal in the management of patients at risk for atherosclerotic coronary heart disease (CHD) with myocardial infarction and coronary death as the main outcomes, and for atherosclerotic cardiovascular disease (ASCVD), which includes CHD and stroke. Recent developments and changes in guidelines affect optimization of using lipid measures as cardiovascular biomarkers. This scientific statement reviews the pre-analytical, analytical, post-analytical, and clinical aspects of lipoprotein measurements. Highlights include the following: i) It is acceptable to screen with nonfasting lipids. ii) non-high-density lipoprotein HDL-cholesterol (non-HDL-C) is measured reliably in either the fasting or the nonfasting state and can effectively guide ASCVD prevention. iii) low density lipoprotein cholesterol (LDL-C) can be estimated from total cholesterol, high density lipoprotein cholesterol (HDL-C), and triglyceride (TG) measurements. For patients with LDL-C>100 mg/dL and TG ≤150 mg/dL it is reasonable to use the Friedewald formula. However, for those with TG 150-400 mg/dL the Friedewald formula for LDL-C estimation is less accurate. The Martin/Hopkins method is recommended for LDL-C estimation throughout the range of LDL-C levels and up to TG levels of 399 mg/dL. For TG levels ≥400 mg/dL LDL-C estimating equations are currently not recommended and newer methods are being evaluated. iv) When LDL-C or TG screening results are abnormal the clinician should consider obtaining fasting lipids. v) Advanced lipoprotein tests using apolipoprotein B (apoB), LDL Particle Number (LDL-P) or remnant cholesterol may help to guide therapeutic decisions in select patients, but data are limited for patients already on lipid lowering therapy with low LDL-C levels. Better harmonization of advanced lipid measurement methods is needed. Lipid measurements are recommended 4-12 weeks after a change in lipid treatment. Lipid laboratory reports should denote desirable values and specifically identify extremely elevated LDL-C levels (≥190 mg/dL at any age or ≥160 mg/dL in children) as severe hypercholesterolemia. Potentially actionable abnormal lipid test results, including fasting triglycerides (TG) ≥500 mg/dL, should be reported as hypertriglyceridemia. Appropriate use and reporting of lipid tests should improve their utility in the management of persons at high risk for ASCVD events. [ABSTRACT FROM AUTHOR]

Non-high density lipoprotein cholesterol (non-HDLC) represents the cholesterol in triglyceride-rich lipoproteins (TRL) and low-density lipoproteins (LDL). Apolipoprotein B (apoB) reflects the number of TRL and LDL particles. In hypertriglyceridemia (HTG), there is triglyceride (TG) enrichment of TRLs, and also a substantial increase of cholesterol in larger TRLs that considerably augments the non-HDLC value. Therefore, in HTG, non-HDLC could increase disproportionately with respect to apoB. We aimed to compare the relative effect of the full range of mild, moderate, and severe HTG on the status of non-HDLC and apoB as cardiovascular disease (CVD) risk markers. Analysis of lipid profile data from 4347 patients in a Lipid Clinic cohort with baseline fasting lipid profiles documented prior to starting lipid-lowering medications. The correlation between non-HDLC and apoB was assessed in intervals of increasing TG. Non-HDLC and apoB were analyzed at each TG level using comparative CVD risk equivalent categories and assessed for divergence and discordance. With increasing TG levels: (1) the correlation between non-HDLC and apoB diminished progressively, (2) non-HDLC levels increased continuously, whereas apoB levels plateaued after an initial increase up to TG of ~ 4.0-5.0 mmol/L (~354-443 mg/dL), (3) there was divergence in the stratification of non-HDLC and apoB into CVD risk equivalent categories. Non-HDLC and apoB should not be viewed as interchangeable CVD risk markers in the presence of severe HTG. This has never been tested. With increasing HTG severity, discordance between non-HDLC and apoB can cause clinically important divergence in CVD risk categorization. • As TG increases, the correlation between non-HDLC and apoB decreases progressively. • In HTG, discordant non-HDLC and apoB causes divergence in CVD risk categorization. • Non-HDLC and apoB should not be viewed as interchangeable CVD risk markers in HTG. [ABSTRACT FROM AUTHOR]

Non–high-density lipoprotein cholesterol (non-HDL-C) includes atherogenic cholesterol and low-density lipoproteins (LDL) and triglyceride-rich lipoproteins. Patients with diabetes frequently have elevations in non-HDL-C. This study examines temporal trends in the levels of non-HDL-C in free-living subjects with diabetes but a negative history of atherosclerotic cardiovascular disease. National Health and Nutrition Examination Surveys conducted between 1999 and 2016 had data from 3,219 adults (aged 40–75 years) with diabetes. Temporal trends in changes in the distribution of total cholesterol, non-HDL-C, LDL cholesterol (LDL-C), and HDL-C were evaluated. Data were weighted to account for complex survey design. Significant decreases were observed in non-HDL-C (20.1%; P <.0001) and total cholesterol (16.1%; P <.0001) levels between 1999 and 2016. No significant changes were noted in HDL-C levels. LDL-C was reduced by 29.6% in a subset of subjects. The reduction in non-HDL-C and LDL-C occurred simultaneously, with an increase of 4.4% of subjects per year taking cholesterol-lowering drugs and statins. In contrast, the fraction of subjects taking antihypertensives or hypoglycemia agents rose at a rate of 2.2% per year. There was also a significant trend for increases in weight gain (P ≤.013). In subjects with diabetes, non-HDL-C levels have declined over time in parallel with reported increases in cholesterol-lowering drugs. Nonetheless, treatment targets for lipids in subjects with diabetes lag behind current recommendations. Reported intakes for antihypertensive agents and hypoglycemia agents were relatively high throughout the period of study, with little change over time. However, there was a trend for weight increase in diabetic subjects, which may offset some of the benefits of pharmacotherapy. • Non–high-density lipoprotein cholesterol has decreased by 20.1% in diabetes mellitus. • Treatment with hypolipidemia drugs increased since 1999. • Weight has increased significantly (P <.013). • Treatment of lipids lags behind recommendations. [ABSTRACT FROM AUTHOR]

Background Atherogenic dyslipidemia is highly prevalent in the Arabian Gulf. Non–high-density lipoprotein cholesterol (non-HDL-C) reduction has been proposed as an additional goal to low-density lipoprotein cholesterol (LDL-C) lowering to prevent atherosclerotic cardiovascular disease (ASCVD). Data on non–HDL-C goal attainment in patients with high triglycerides (TGs) on lipid-lowering drugs (LLDs) in the region is scarce. Objective Evaluate non–HDL-C target attainment according to the National Lipid Association in patients on LLDs stratified by TG (<150 [1.69], 150–200 [1.69–2.26], >200 [2.26] mg/dL [mmol/L]) levels in the Arabian Gulf. Methods Overall, 4383 patients on LLD treatment from 6 Middle Eastern countries participating in the Centralized Pan-Middle East Survey on the Undertreatment of Hypercholesterolemia study were evaluated. Patients were classified according to TG levels and ASCVD risk. Results The overall non–HDL-C goal attainment was 41% of the subjects. Non–HDL-C goal was less likely attained in patients with high TGs (12% vs 27% vs 55%; P < .001). Very high ASCVD risk patients with high TGs attained less their non–HDL-C targets compared with those with lower TG levels (8% vs 23% vs 51%; P < .001). Similarly, high ASCVD risk patients with high TGs also failed more in attaining non–HDL-C targets compared with those with lower TGs (26% vs 42% vs 69%; P < .001). In addition, those with high TG also succeeded less in attaining LDL-C and apolipoprotein B goals ( P < .001). Conclusions A large proportion of very high and high ASCVD patients on LLDs in the Arabian Gulf are not at recommended non–HDL-C targets and hence remain at a substantial residual risk. [ABSTRACT FROM AUTHOR]

Background Low-density lipoprotein cholesterol (LDL-C) is the primary target of lipid-lowering therapy in people at risk for cardiovascular diseases. Mipomersen inhibits apolipoprotein B-100 (apoB) synthesis and causes reduction in LDL-C by reducing apoB. Objective We aimed to perform a meta-analysis of all published randomized controlled trials comparing safety and efficacy of mipomersen with placebo in adults with dyslipidemia. Methods We searched PUBMED, CENTRAL, and EMBASE from inception through March 2014 and used random-effects model to compute the effect size. Results We identified 8 randomized controlled trials (n = 462). Mipomersen compared with placebo significantly reduced LDL-C by 32.37% (95% confidence interval, 25.55–39.18; P < .00001), total cholesterol by 24.18% (18.54–29.83; P < .00001), very low–density lipoprotein cholesterol by 21.59% (9.16–34.02; P = .0007), non–high-density lipoprotein cholesterol (HDL-C) by 30.83% (23.92–37.74; P < .00001), and triglycerides by 36.26% (22–50.54; P < .00001). It also significantly reduced apoB, lipoprotein(a), and apolipoprotein A1. However, mipomersen did not significantly change HDL-C levels. In safety analysis, mipomersen compared with placebo increased the risks of injection-site reaction (risk ratio, 2.05; 95% confidence interval, 1.39–3.04; P = .0003), flu-like symptoms (1.63; 1.22–2.17; P = .0008), alanine aminotransferase ≥3X upper limit of normal (4.44; 1.67–11.86; P = .003), and hepatic steatosis (3.85, 1.39–10.67; P = .01). The risks of alanine aminotransferase ≥10X upper limit of normal did not reach statistical significance (1.57; 0.32–7.6, P = .58). Conclusion Mipomersen resulted in a significant improvement in lipid parameters except for HDL-C and increased the risks of injection-site reactions, flu-like symptoms, and hepatic steatosis compared with placebo. [ABSTRACT FROM AUTHOR]

Background Non–high-density lipoprotein cholesterol (non–HDL-C) has been identified as a significant predictor of various cardiovascular events in adults. Limited studies have been conducted in the pediatric population with diverse results, depending on ethnic origin. None has been conducted in the Arabic adolescent population so far; this study aims to fill this gap. Methods In this cross-sectional study, 1690 Saudi school adolescents (968 boys [mean age 14.8 ± 1.7] and 722 girls [mean age 14.6 ± 1.7]) were recruited. Anthropometrics were obtained. Fasting blood glucose and lipid profiles were quantified routinely. Non–HDL-C was calculated and screening was done for dyslipidemia using cutoffs obtained from the cohort and elevated fasting glucose. Results Using the 90th percentile cutoff obtained, the overall prevalence of high non–HDL-C (≥4.26 mmol/L) was 10.1%. Prevalence was slightly higher in girls (10.5%) than boys (9.9%). Non–HDL-C was similar to other lipids in terms of significant associations with anthropometric measures and glucose in both boys and girls. Elevated triglycerides was most predictive of elevated glucose in both girls (odds ratio 2.41; confidence interval 1.43–4.08; P = .001) and boys (odds ratio 2.61; confidence interval 1.70–4.0); P < .001). Conclusion Non–HDL-C appears to be gender-specific and is cardiometabolically more associated with Saudi boys, despite higher levels in girls. It is inferior compared with triglycerides in assessing elevated glucose risk. Further investigations may provide a more definite value for non–HDL-C use as a biomarker in assessing cardiometabolic risk in the Arab adolescent population. [ABSTRACT FROM AUTHOR]

Background: The preference of the apolipoprotein (apo) B/apoA-I ratio over the total cholesterol/HDL cholesterol (TC/HDL-C) ratio in cardiovascular risk prediction is disputed. Cholesteryl ester transfer protein (CETP) is instrumental in lipoprotein remodelling and affects the cholesterol content in pro- and antiatherogenic lipoproteins relative to their major apolipoproteins. We tested the influence of common CETP variations on the strength of associations of a first major adverse cardiovascular event (MACE) with the apoB/apoA-I ratio compared with the TC/HDL-C ratio. Methods: A prospective case-cohort study was performed (PREVEND cohort; no previous cardiovascular disease and no use of lipid-lowering drugs initially). Fasting serum TC/HDL-C, apoB/apoA-I, triglycerides, and common CETP variations (TaqIB [rs708272] and -629C>A [rs1800775] polymorphisms) were measured at baseline. The composite end point was incident MACE. Results: A total of 532 of 6780 subjects experienced a first MACE during 10.8 years follow-up. The age- and sex-adjusted hazard ratio was 1.31 (95 % confidence interval 1.23–1.41) for the apoB/apoA-I ratio and 1.22 (95% confidence interval 1.26–1.39) for the TC/HDL-C ratio (both P < .001). These relationships were essentially similar within each TaqIB and -629C>A CETP genotype group. No interactions of the apoB/apoA-I ratio and the TC/HDL-C ratio with the TaqIB and the -629C>A CETP variations on incident MACE were observed (P > .20 for all). Conclusion: The relationship of first MACE with the TC/HDL-C and the apoB/apoA-I ratio is not to an important extent dependent on common CETP variations. CETP variations are unlikely to affect the strength of the relationship of first MACE with the apoB/apoA-I ratio compared with the TC/HDL-C ratio. [ABSTRACT FROM AUTHOR]

Background: The Adult Treatment Panel III guidelines established non–high-density lipoprotein cholesterol (non-HDL-C) as a secondary treatment target. However, non-HDL-C levels are not reported on standard lipid panels by many hospital-based and/or commercial biochemical laboratories. Objective: We determined whether reporting non-HDL-C was associated with improved non-HDL-C goal attainment. Methods: We identified patients with cardiovascular disease (CVD) and/or diabetes receiving care within the Veterans Health Administration. We matched a facility that reported non-HDL-C levels on lipid panels (3994 CVD and 5108 diabetes patients) to a facility with similar size, patient complexity, and academic mission that did not report non-HDL-C (4269 CVD and 6591 diabetes patients). We performed patient-level analysis to assess differences in non-HDL-C from baseline to the most recent lipid panel at these facilities. Results: Baseline non-HDL-C levels for CVD patients were 114 mg/dL and 107 mg/dL at the reporting and nonreporting facilities, respectively. At 2.3-year follow-up, non-HDL-C levels decreased at both facilities but by a greater amount at the reporting facility (−11 mg/dL vs −3 mg/dL at the nonreporting facility, P < .001). Results remained significant (P < .001) after we adjusted for patient''s age, race, gender, illness burden, history of diabetes, hypertension, medication adherence, statin use, number of lipid panels, and number of primary care visits between baseline and follow-up. Reductions were greater among CVD patients with triglycerides ≥200 mg/dL (−25 mg/dL vs −16 mg/dL at the respective facilities, P = .004). Results were similar in diabetes patients. Reporting was also associated with greater proportions of patients meeting non-HDL-C treatment goal of <130 mg/dL. Conclusion: Non-HDL-C reporting could improve non-HDL-C goal attainment. [Copyright &y& Elsevier]

Abstract: There is little understanding of the reliability of laboratory measurements among clinicians. Low-density lipoprotein cholesterol (LDL-C) measurement is the cornerstone of cardiovascular risk assessment and prevention, but it is fraught with error. Therefore, we have reviewed issues related to accuracy and precision for the measurement of LDL-C and the related markers non-high-density lipoprotein cholesterol (non-HDL-C) and apolipoprotein B. Despite the widespread belief that LDL-C is standardized and reproducible, available data suggest that results can vary significantly as the result of methods from different manufacturers. Similar problems with direct HDL-C assays raise concerns about the reliability of non-HDL-C measurement. The root cause of method-specific bias relates to the ambiguity in the definition of both LDL and HDL, and the heterogeneity of LDL and HDL particle size and composition. Apolipoprotein B appears to provide a more reliable alternative, but assays for it have not been as rigorously tested as direct LDL-C and HDL-C assays. [Copyright &y& Elsevier]

Background: Dysbetalipoproteinemia, also known as type III hyperlipoproteinemia (type III HL), is characterized by the accumulation of β-very low density lipoprotein (β-VLDL). However, demonstration of the presence of β-VLDL is not easy because it requires preparative ultracentrifugation of lipoproteins. The primary genetic defect in type III HL is the presence of apolipoprotein (apo) E2, a mutant form of apoE. However, another metabolic defect, such as overproduction of VLDL, is also required for the full phenotype. Patients with only E2 homozygosity usually do not have HL. Because apoE genotyping is expensive, the selection of patients for this analysis by effective use of common clinical measures would be very helpful. Objective: We examined the non-HDL-C/apoB ratio as an index for type III HL screening. Methods: We studied nine patients with type III HL. Most patients with type III HL show mixed hyperlipidemia. We compared the plasma of patients with combined hyperlipidemia and the dyslipidemia of hypothyroidism with those with type III HL. The serum levels of total cholesterol, triglyceride, and high-density lipoprotein cholesterol (HDL-C), as well as the serum apoB and apoE levels, were measured by routine laboratory methods. Results: Individual values of serum lipids and apolipoproteins did not distinguish type III HL from the two other types of HL. The non-HDL-C/apoB ratio in type III HL was significantly greater than that in the two comparison groups, with no overlap. Conclusion: The non-HDL-C/apoB ratio is a novel index that appears to be reliable for screening of patients for type III HL, and the index can be determined at regular clinical laboratories without the need for any complicated lipoprotein analysis. Thus, we propose the clinical usefulness of this index. [Copyright &y& Elsevier]

Background: The cholesterol content of low-density lipoprotein (LDL) particles is variable, causing frequent discrepancies between concentrations of LDL cholesterol (LDL-C) and LDL particle number (LDL-P). In managing patients at risk for cardiovascular disease (CVD) to LDL target levels, it is unclear whether LDL-C provides the optimum measure of residual risk and adequacy of LDL-lowering treatment. Objective: To compare the ability of alternative measures of LDL to provide CVD risk discrimination at relatively low levels consistent with current therapeutic targets. Methods: Concentrations of LDL-C and non–HDL-C were measured chemically and LDL-P and VLDL-P were measured by nuclear magnetic resonance in 3066 middle-aged white participants (53% women) without CVD in the Framingham Offspring cohort. The main outcome measure was incidence of first CVD event. Results: At baseline, the cholesterol content per LDL particle was negatively associated with triglycerides and positively associated with LDL-C. On follow-up (median 14.8 years), 265 men and 266 women experienced a CVD event. In multivariable models adjusting for nonlipid CVD risk factors, LDL-P was related more strongly to future CVD in both genders than LDL-C or non–HDL-C. Subjects with a low level of LDL-P (<25th percentile) had a lower CVD event rate (59 events per 1000 person-years) than those with an equivalently low level of LDL-C or non–HDL-C (81 and 74 events per 1000 person-years, respectively). Conclusions: In a large community-based sample, LDL-P was a more sensitive indicator of low CVD risk than either LDL-C or non–HDL-C, suggesting a potential clinical role for LDL-P as a goal of LDL management. [Copyright &y& Elsevier]

Secondary dyslipidemia with predominant hypertriglyceridemia may occur as a consequence of both common and rare causes. After accounting for obesity and associated insulin resistance, clinicians should carefully consider other contributing factors and conditions. Genetic background and causative factors prevail during gestation, infancy, and childhood and continue in adults. Elevations in triglyceride (TG) are associated with transfer of TG to high-density lipoprotein (HDL) and low-density lipoprotein (LDL) resulting in lipolysis, HDL degradation, and formation of atherogenic LDL particles. Defining and treating the underlying cause is the first step toward restoring the lipids and lipoproteins to normal, especially in cases with severe hypertriglyceridemia, who are at risk for acute pancreatitis. Disorders involving the liver, kidney, endocrine, and immune systems and medications need to be considered. Rare diseases such as lipodystrophy and glycogen storage disease are particularly challenging, and there have been promising new developments. Treatment depends on the severity; prevention of acute pancreatitis being a priority in severe cases and lifestyle modification being a foundation for general management followed by targeting TG and predictors of coronary artery disease such as LDL cholesterol and non–HDL cholesterol, when they exceed cutpoints. [ABSTRACT FROM AUTHOR]