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Objectives: The aim of this study was to examine the effect of PCSK9 R46L on low-density lipoprotein cholesterol (LDL-C), risk of ischemic heart disease (IHD), and mortality. Background: The 46L allele has been associated with reductions in LDL-C and risk of IHD, but results vary between studies. Methods: We determined the association of R46L genotype with LDL-C, risk of IHD, myocardial infarction (MI), and mortality in the prospective CCHS (Copenhagen City Heart Study) (n = 10,032) and validated the results in: 1) the cross-sectional CGPS (Copenhagen General Population Study) (n = 26,013); and 2) the case-control CIHDS (Copenhagen Ischemic Heart Disease Study) (n = 9,654). We also performed meta-analyses of present and previous studies (n = 66,698). Results: In carriers (2.6%) versus noncarriers, the 46L allele was associated with reductions in LDL-C of 0.35 to 0.55 mmol/l (11% to 16%) from 20 to 80+ years in the general population (CCHS and CGPS; p values <0.0001). Observed risk reductions for IHD in 46L allele carriers were: 6% in the CCHS study (hazard ratio [HR]: 0.94; 95% confidence interval [CI]: 0.68 to 1.31), 46% in the CGPS study (odds ratio [OR]: 0.54; 95% CI: 0.39 to 0.77), 18% in the CIHDS study (OR: 0.82; 95% CI: 0.55 to 1.21), and 30% in the studies combined (OR: 0.70; 95% CI: 0.58 to 0.86). In the CCHS study, HR for mortality was 1.18 (95% CI: 0.93 to 1.50). In meta-analyses, 46L allele carriers had a 12% (0.43 mmol/l) reduction in LDL-C and a 28% reduction in risk of IHD (HR: 0.72; 95% CI: 0.62 to 0.84), similar to results in the CCHS, CGPS, and CIHDS studies combined. However, the observed 12% (0.43 mmol/l) reduction in LDL-C theoretically predicted an only 5% reduction in risk of IHD (HR: 0.95; 95% CI: 0.92 to 0.97). Conclusions: The PCSK9 46L allele was associated with reductions in LDL-C from 20 to 80+ years in the general population. The reduction in risk of IHD was larger than predicted by the observed reduction in LDL-C alone. This could be because genotype is a better predictor of lifelong exposure to LDL-C than LDL-C measured in adult life. [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]

Background: Familial hypercholesterolemia (FH) is a condition with very high concentrations of low-density lipoprotein (LDL) cholesterol and high risk of ischemic heart disease including myocardial infarction. However, there is limited and contradictory information on whether FH and high LDL cholesterol per se confer high risk of ischemic stroke. We tested the hypotheses that individuals in the general population with FH and/or high LDL cholesterol have higher risk of ischemic stroke.Methods: The associations of FH and high LDL cholesterol with ischemic stroke risk were tested in both causal, genetic, and observational analyses using 106 412 individuals from the CGPS (Copenhagen General Population Study; 2823 ischemic strokes and 3792 myocardial infarctions) and/or 10 372 individuals from the CCHS (Copenhagen City Heart Study; 945 ischemic strokes and 1142 myocardial infarctions). FH causative mutations were LDLR W23X(rs267607213), W66G(rs121908025) and W556S, and APOB R3500Q(rs5742904). A Mendelian randomization design tested whether high LDL cholesterol per se has a causal effect on ischemic stroke risk, using a combination of the FH causative mutations and common genetic variants associated with high LDL cholesterol.Results: The cumulative incidences in individuals in the CGPS with and without FH causative mutations were similar for ischemic stroke ( P=0.50) but not for myocardial infarction ( P<0.001): at age 80 years, 4% and 7% of these individuals developed ischemic stroke and 20% and 8% myocardial infarction, with similar results in the CCHS. There was no association between clinical FH and ischemic stroke, except if personal premature ischemic heart disease was included in the clinical FH criteria. Ischemic heart disease at baseline was associated with higher ischemic stroke risk, explaining the higher ischemic stroke risk in those with high LDL cholesterol. For a 1 mmol/L higher LDL cholesterol, the genetic causal risk ratio was 1.11 (0.62-2.02) for ischemic stroke and 1.45 (1.08-1.93) for myocardial infarction.Conclusions: FH and high LDL cholesterol did not confer an increased risk of ischemic stroke. A positive association with ischemic stroke observed for some clinical FH criteria and high LDL cholesterol appears to be due to previous ischemic heart disease, rather than to high LDL cholesterol per se. [ABSTRACT FROM AUTHOR]

During fat tolerance tests, plasma triglycerides increase while high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and intermediate-density lipoprotein (IDL) cholesterol decrease. However, it is unknown whether triglyceride content increases and cholesterol content decreases in HDL and LDL + IDL fractions following normal meals in the general population. Therefore, we tested the hypothesis that triglyceride content increases while cholesterol content decreases in HDL and LDL + IDL fractions following normal meals. In this cross-sectional study, we included 25,656 individuals aged 20–100 years, all without lipid-lowering therapy at examination and selected for metabolomic profiling from the Copenhagen General Population Study. Triglyceride and cholesterol content of 14 lipoprotein fractions weas measured using nuclear magnetic resonance (NMR) spectroscopy. Time since last meal was recorded by the examiner immediately before blood sampling. Following normal meals in age and sex-adjusted analyses and when compared with fasting levels, plasma triglycerides were higher for up to 5–6 h, and triglyceride content was higher for up to 6–7 h in HDL fractions, for up to 6–7 h in LDL + IDL fractions, and for up to 5–6 h in very-low-density lipoprotein (VLDL) fractions. Further, plasma cholesterol was lower for up to 2–3 h, and cholesterol content was lower for up to 0–1 h in HDL fractions and for up to 4–5 h in LDL + IDL fractions, while cholesterol content was higher for up to 4–5 h in VLDL fractions. Following normal meals, triglyceride content increases while cholesterol content decreases in HDL and LDL + IDL fractions. [Display omitted] • Following normal meals, triglyceride content increases in HDL and LDL + IDL fractions. • Following normal meals, cholesterol content decreases in HDL and LDL + IDL fractions. • Following normal meals, cholesterol content decreases in the smallest HDL fractions. • Following normal meals, cholesterol content increases in the largest VLDL fractions. • Results were similar in women and men, and in individuals with low and high BMI. [ABSTRACT FROM AUTHOR]

Background--Elevated nonfasting remnant cholesterol and low-density lipoprotein (LDL) cholesterol are causally associated with ischemic heart disease (IHD), but whether elevated nonfasting remnant cholesterol and LDL cholesterol both cause low-grade inflammation is currently unknown. Methods and Results--We studied 60 608 individuals from the Copenhagen General Population Study, the Copenhagen City Heart Study, and the Copenhagen Ischemic Heart Disease study, of whom 10 668 had IHD diagnosed between 1977 and 2011. We genotyped for variants affecting levels of nonfasting remnant cholesterol, LDL cholesterol, C-reactive protein by CRP alleles, and C-reactive protein by IL6R alleles. Using a multidirectional mendelian randomization design, we investigated possible causal associations between the lipoproteins and C-reactive protein and between the lipoproteins and IHD. A 1-mmol/L(39 mg/dL) higher level of nonfasting remnant cholesterol was associated observationally with a 37% (95% confidence interval, 35-39) higher C-reactive protein level and causally with a 28% (95% confidence interval, 10-48) higher level. For LDL cholesterol, a 1-mmol/L (39-mg/dL) higher level was associated observationally with a 7% (95% confidence interval, 6-7) higher C-reactive protein level, but we found no causal association. Likewise, higher levels of C-reactive protein did not associate causally with elevated nonfasting remnant cholesterol or LDL cholesterol. Finally, the causal risk ratio for IHD for a 1-mmol/L (39-mg/dL) higher level was 3.3 (95% confidence interval, 2.1-5.2) for nonfasting remnant cholesterol and 1.8 (95% confidence interval, 1.5-2.2) for LDL cholesterol. The causal associations for remnant cholesterol were present even in those without diabetes mellitus and obesity. Conclusions--Elevated nonfasting remnant cholesterol is causally associated with low-grade inflammation and with IHD, whereas elevated LDL cholesterol is associated causally with IHD without inflammation. [ABSTRACT FROM AUTHOR]

Background & Aims: Drugs which reduce plasma low-density lipoprotein cholesterol (LDL-C) may protect against gallstone disease. Whether plasma levels of LDL-C per se predict risk of gallstone disease remains unclear. We tested the hypothesis that elevated LDL-C is a causal risk factor for symptomatic gallstone disease. Methods: We used a Mendelian randomization approach and genotyped 63,051 individuals from a prospective cohort study of the general Danish population, including 3323 subjects with symptomatic gallstones. We selected eight genetic variants in APOE, APOB, LDLR, and PCSK9 affecting LDL-C. Furthermore, studies of APOE rs429358/rs7412 (defining ε2/ε3/ε4 alleles; 12 studies) and APOB rs693 (eight studies) were included in meta-analyses. Results: The observational hazard ratio (HR) for symptomatic gallstone disease for the fifth versus first quintile of LDL-C was 0.94 (95% confidence interval: 0.76–1.17), despite a corresponding 134% increase in LDL-C. Furthermore, although individual genetic variants in APOE, APOB, LDLR, and PCSK9 associated with stepwise increases/decreases in LDL-C of up to +59% compared with non-carriers (p <0.001), none predicted the risk of symptomatic gallstone disease. Combining all variants into 10 genotypes, carriers of 9 versus ⩽3 LDL-C increasing alleles associated with 41% increased LDL-C (p <0.001), but predicted a HR for symptomatic gallstone disease of 1.09 (0.70–1.69). Finally, in meta-analyses, random effects odds ratios for gallstone disease were 0.91 (0.78–1.06) for carriers of APOE ε4 versus non-carriers, and 1.25 (0.95–1.63) for APOB rs693 CT+TT versus CC. Conclusions: Results from the observational study, genetic studies, and meta-analyses suggest that elevated plasma levels of LDL-C are not causally associated with increased risk of symptomatic gallstone disease. [ABSTRACT FROM AUTHOR]

Objectives: The goal of this study was to determine whether residual risk after high-dose statin therapy for primary prevention individuals with reduced levels of low-density lipoprotein cholesterol (LDL-C) is related to on-treatment apolipoprotein B, non–high-density lipoprotein cholesterol (non–HDL-C), trigylcerides, or lipid ratios, and how they compare with on-treatment LDL-C. Background: Guidelines focus on LDL-C as the primary target of therapy, yet residual risk for cardiovascular disease (CVD) among statin-treated individuals remains high and not fully explained. Methods: Participants in the randomized placebo-controlled JUPITER (Justification for the Use of Statins in Prevention: An Intervention Trial Evaluating Rosuvastatin) trial were adults without diabetes or CVD, with baseline LDL-C levels <130 mg/dl, high-sensitivity C-reactive protein levels ≥2 mg/l, and triglyceride concentrations <500 mg/dl. Individuals allocated to receive rosuvastatin 20 mg daily with baseline and on-treatment lipids and lipoproteins were examined in relation to the primary endpoint of incident CVD (nonfatal myocardial infarction or stroke, hospitalization for unstable angina, arterial revascularization, or cardiovascular death). Results: Using separate multivariate Cox models, statistically significant associations of a similar magnitude with residual risk of CVD were found for on-treatment LDL-C, non–HDL-C, apolipoprotein B, total cholesterol/HDL-C, LDL-C/HDL-C, and apolipoprotein B/A-I. The respective adjusted standardized hazard ratios (95% confidence intervals) for each of these measures were 1.31 (1.09 to 1.56), 1.25 (1.04 to 1.50), 1.27 (1.06 to 1.53), 1.22 (1.03 to 1.44), 1.29 (1.09 to 1.52), and 1.27 (1.09 to 1.49). The overall residual risk and the risk associated with these measures decreased among participants achieving on-treatment LDL-C ≤70 mg/dl, on-treatment non–HDL-C ≤100 mg/dl, or on-treatment apolipoprotein B ≤80 mg/dl. In contrast, on-treatment triglycerides showed no association with CVD. Conclusions: In this primary prevention trial of nondiabetic individuals with low LDL-C and elevated high-sensitivity C-reactive protein, on-treatment LDL-C was as valuable as non–HDL-C, apolipoprotein B, or ratios in predicting residual risk. (JUPITER—Crestor 20mg Versus Placebo in Prevention of Cardiovascular [CV] Events; NCT00239681) [Copyright &y& Elsevier]