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The joint consensus panel of the European Atherosclerosis Society (EAS) and the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) recently addressed present and future challenges in the laboratory diagnostics of atherogenic lipoproteins. Total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, and calculated non-HDL cholesterol (=total – HDL cholesterol) constitute the primary lipid panel for estimating risk of atherosclerotic cardiovascular disease (ASCVD) and can be measured in the nonfasting state. LDL cholesterol is the primary target of lipid-lowering therapies. For on-treatment follow-up, LDL cholesterol shall be measured or calculated by the same method to attenuate errors in treatment decisions due to marked between-method variations. Lipoprotein(a)-cholesterol is part of measured or calculated LDL cholesterol and should be estimated at least once in all patients at risk of ASCVD, especially in those whose LDL cholesterol decline poorly upon statin treatment. Residual risk of ASCVD even under optimal LDL-lowering treatment should be also assessed by non-HDL cholesterol or apolipoprotein B, especially in patients with mild-to-moderate hypertriglyceridemia (2–10 mmol/L). Non-HDL cholesterol includes the assessment of remnant lipoprotein cholesterol and shall be reported in all standard lipid panels. Additional apolipoprotein B measurement can detect elevated LDL particle numbers often unidentified on the basis of LDL cholesterol alone. Reference intervals of lipids, lipoproteins, and apolipoproteins are reported for European men and women aged 20–100 years. However, laboratories shall flag abnormal lipid values with reference to therapeutic decision thresholds. Image 1 • Total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, and calculated non-HDL cholesterol (=total – HDL cholesterol) constitute the primary lipid panel for estimating risk of atherosclerotic cardiovascular disease (ASCVD) and can be measured in the nonfasting state. • LDL cholesterol is the primary target of lipid-lowering therapies. • Lipoprotein(a)-cholesterol is part of measured or calculated LDL cholesterol and lipoprotein(a) should be measured at least once in all patients. • Residual risk of ASCVD even under optimal LDL-lowering treatment should be also assessed by non-HDL cholesterol or apolipoprotein B, especially in patients with mild-to-moderate hypertriglyceridemia (2-10 mmol/L). • Non-HDL cholesterol includes the assessment of remnant lipoprotein cholesterol and shall be reported in all standard lipid panels. • Laboratories shall flag abnormal lipid values with reference to therapeutic decision thresholds. [ABSTRACT FROM AUTHOR]

The G188E, D9N, and N291S mutations in LPL increase TG, reduce HDL cholesterol, and increase risk of ischemic heart disease. The common S447X mutation may have opposite effects. We genotyped 8451 women and men from the Danish general population, and 854 women and men with ischemic heart disease. Participants carrying G188E, D9N, or N291S were excluded. Compared with non-carriers, female heterozygotes and homozygotes presented with a 0.11 and 0.18 mmol/l decrease in plasma TG (P=0.001 and P=0.37) and a 0.07 and 0.03 mmol/l increase in HDL cholesterol (P=0.001 and P=0.99). Male heterozygotes and homozygotes presented with a 0.20 and 0.41 mmol decrease in plasma TG (P<0.001 and P=0.06), which was twice that in women, and a 0.05 and 0.17 mmol/l increase in plasma HDL cholesterol (P=0.02 and P=0.04), respectively. In meta-analyses by gender, the S447X mutation was associated with a significant l7% reduction in risk of ischemic heart disease in men (OR=0.83; P=0.01), whereas risk was unaffected in women (OR=0.97; P=0.98). The S447X mutation is associated with anti-atherogenic effects on TG and HDL cholesterol in both genders, and with a moderate protective effect on risk of ischemic heart disease in men. [Copyright &y& Elsevier]

The PROMINENT trial, a cardiovascular outcome trial of the triglyceride- and remnant cholesterol-lowering agent pemafibrate, has shown neutral results despite reduction in plasma triglycerides and remnant cholesterol. We tested the hypothesis that absolute mass changes in remnant cholesterol, LDL cholesterol, and apolipoprotein B explain the results of the PROMINENT trial. Among 108,431 individuals from the Copenhagen General Population Study (CGPS), those who met the key inclusion criteria of the PROMINENT trial were analyzed to mimic the trial design. Endpoint atherosclerotic cardiovascular disease (ASCVD) was cardiovascular death, myocardial infarction, ischemic stroke, and coronary revascularization as defined in PROMINENT. In the PROMINENT trial, treatment with pemafibrate resulted in -7 mg/dL (−0.18 mmol/L; -18 %) change in remnant cholesterol, +10 mg/dL (+0.26 mmol/L; +12 %) LDL cholesterol, and +5 mg/dL (+0.05 g/L; +5 %) apolipoprotein B. In the CGPS mimicking PROMINENT, the estimated hazard ratios for ASCVD were 0.97 (95 % confidence interval: 0.94–0.99) for a -7 mg/dL (−0.18 mmol/L) change in remnant cholesterol, 1.04 (1.01–1.07) for a +10 mg/dL (+0.26 mmol/L) change in LDL cholesterol, and 1.02 (1.01–1.03) for a +5 mg/dL (+0.05 g/L) change in apolipoprotein B. When combining absolute changes in remnant cholesterol, LDL cholesterol, and apolipoprotein B, the estimated hazard ratio for ASCVD was 1.05 (0.96–1.14) in the CGPS mimicking PROMINENT compared to 1.03 (0.91–1.15) in the PROMINENT trial. Absolute mass changes in remnant cholesterol, LDL cholesterol, and apolipoprotein B can explain results of the PROMINENT trial. The 3 mg/dL (0.08 mmol/L) higher total atherogenic cholesterol together with 5 mg/dL (0.05 g/L) higher apolipoprotein B seem to explain the trend toward more ASCVD in the pemafibrate arm. [Display omitted] • Absolute mass changes in remnant cholesterol, LDL cholesterol, and apo B can explain results of the PROMINENT trial. • To reduce ASCVD lipid lowering drugs, total atherogenic cholesterol and total number of atherogenic particles need to be reduced. • Understanding the potential for causing ASCVD, lipoproteins should be judged by their absolute mass of cholesterol content. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Zinc Finger Protein 202 (ZNF202) is a transcriptional repressor of genes affecting the vascular endothelium as well as lipid metabolism. A phenotype associated with genetic variation in ZNF202 is presently unknown. We tested the hypothesis that a common variant in ZNF202, A154V, predicts risk of ischemic heart disease (IHD), myocardial infarction (MI), and ischemic cerebrovascular disease (ICVD). Methods and results: We conducted a prospective study of more than 9000 individuals from the general population with 24 years follow-up. In women, age-adjusted hazard ratios in heterozygotes and homozygotes versus non-carriers were 1.2 (95% CI: 1.0–1.5, P =0.04) and 1.5 (1.1–2.1, P =0.007) for IHD, 1.5 (1.1–2.1; P =0.01) and 1.7 (1.1–2.8, P =0.02) for MI, and 1.3 (1.0–1.8, P =0.07) and 1.3 (0.8–2.1; P =0.33) for ICVD. Adjustments for lipids and lipoproteins did not alter these hazard ratios substantially. Genotype did not predict risk in men. Finally, results for IHD were borderline significant (P =0.06) in an independent case–control study including 933 patients and 8068 controls. Conclusion: This is the first study to suggest that ZNF202 could be a new candidate gene for IHD and MI in the general population. [Copyright &y& Elsevier]

Increased concentrations of calculated remnant cholesterol in triglyceride-rich lipoproteins are observationally and genetically, causally associated with increased risk of ischemic heart disease; however, when measured directly, the fraction of plasma cholesterol present in remnant particles is unclear. We tested the hypothesis that a major fraction of plasma cholesterol is present in remnant lipoproteins in individuals in the general population. We examined 9293 individuals from the Copenhagen General Population Study using nuclear magnetic resonance spectroscopy measurements of total cholesterol, free- and esterified cholesterol, triglycerides, phospholipids, and particle concentration. Fourteen subclasses of decreasing size and their lipid constituents were analysed: six subclasses were very low-density lipoprotein (VLDL), one intermediate-density lipoprotein (IDL), three low-density lipoprotein (LDL), and four subclasses were high-density lipoprotein (HDL). Remnant lipoproteins were VLDL and IDL combined. Mean nonfasting cholesterol concentration was 1.84 mmol/L (72 mg/dL) for remnants, 2.01 mmol/L (78 mg/dL) for LDL, and 1.83 mmol/L (71 mg/dL) for HDL, equivalent to remnants containing 32% of plasma total cholesterol. Of 14 lipoprotein subclasses, large LDL and IDL were the ones containing most of plasma cholesterol. The plasma concentration of remnant cholesterol was from ∼1.4 mmol/L (54 mg/dL) at age 20 to ∼1.9 mmol/L (74 mg/dL) at age 60. Corresponding values for LDL cholesterol were from ∼1.5 mmol/L (58 mg/dL) to ∼2.1 mmol/L (81 mg/dL). Using direct measurements, one third of total cholesterol in plasma was present in remnant lipoproteins, that is, in the triglyceride-rich lipoproteins IDL and VLDL. Image 1 • Using NMR, a third of plasma cholesterol was present in remnant lipoproteins. • Of 14 lipoprotein subclasses, large LDL and IDL were containing most cholesterol. • Directly measured remnant cholesterol was highest in older individuals. [ABSTRACT FROM AUTHOR]