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This article discusses the results of six randomized trials that examined the effects of fibrates and gemfibrozil on the prevention of atherosclerotic cardiovascular disease (ASCVD). The trials showed inconsistent results, and the authors sought to understand these discrepancies by examining the effects of mass changes in remnant cholesterol and LDL cholesterol. Using the Copenhagen General Population Study (CGPS) to mimic the study population of these trials, the authors compared estimated changes in ASCVD risk through mass changes in cholesterol with the observed changes in the original trials. The results suggest that mass changes in total atherogenic cholesterol can explain the results of these trials, regardless of whether statins were used or not. The authors conclude that to reduce ASCVD, cholesterol-lowering agents should aim to reduce the total mass of atherogenic cholesterol. [Extracted from the article]

Said differently, LDL cholesterol cannot be too low after a myocardial infarction and all patients with a myocardial infarction should receive LDL cholesterol-lowering medication post myocardial infarction irrespective of their LDL cholesterol levels at the time of the infarct. Just as age - these comorbidities increase the risk of dying during follow-up for patients with low LDL cholesterol at myocardial infarction compared with those with high LDL cholesterol at myocardial infarction. Elevated low-density lipoprotein (LDL) cholesterol is a causal risk factor for the development of atherosclerosis and drives an increased risk of both myocardial infarction and early death. [Extracted from the article]

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]

Background: Plasma apolipoprotein B (apoB) is a composite measure of all apoB-containing lipoproteins causing atherosclerotic cardiovascular disease; however, it is unclear which fraction of risk is explained by cholesterol and triglycerides, respectively, in very low-density lipoproteins (VLDLs).Objectives: The authors tested the hypothesis that VLDL cholesterol and triglycerides each explain part of the myocardial infarction risk from apoB-containing lipoproteins.Methods: Nested within 109,751 individuals from the Copenhagen General Population Study, the authors examined 25,480 subjects free of lipid-lowering therapy and myocardial infarction at study entry. All had measurements of plasma apoB (quantitating number of apoB-containing lipoproteins) and cholesterol and triglyceride content of VLDL, intermediate-density lipoproteins (IDLs), and low-density lipoproteins (LDLs).Results: During a median 11 years of follow-up, 1,816 were diagnosed with myocardial infarction. Per 1-mmol/l higher levels, multivariable-adjusted hazard ratios for myocardial infarction were 2.07 (95% confidence interval [CI]: 1.81 to 2.36) for VLDL cholesterol, 1.19 (95% CI: 1.14 to 1.25) for VLDL triglycerides, 5.38 (95% CI: 3.73 to 7.75) for IDL cholesterol, and 1.86 (95% CI: 1.62 to 2.14) for LDL cholesterol. Per 1-g/l higher plasma apoB, the corresponding value was 2.21 (95% CI: 1.90 to 2.58). In a step-up Cox regression, risk factors for myocardial infarction entered by importance as VLDL cholesterol, systolic blood pressure, smoking, and IDL + LDL cholesterol, whereas VLDL triglycerides did not enter the model. VLDL cholesterol explained 50% and IDL + LDL cholesterol 29% of the risk of myocardial infarction from apoB-containing lipoproteins, whereas VLDL triglycerides did not explain risk.Conclusions: VLDL cholesterol explained one-half of the myocardial infarction risk from elevated apoB-containing lipoproteins, whereas VLDL triglycerides did not explain risk. [ABSTRACT FROM AUTHOR]