Epigenetic Regulation of F2RL3 Associates With Myocardial Infarction and Platelet Function.

BACKGROUND: DNA hypomethylation at the F2RL3 (F2R like thrombin or trypsin receptor 3) locus has been associated with both smoking and atherosclerotic cardiovascular disease; whether these smoking-related associations form a pathway to disease is unknown. F2RL3 encodes protease-activated receptor 4, a potent thrombin receptor expressed on platelets. Given the role of thrombin in platelet activation and the role of thrombus formation in myocardial infarction, alterations to this biological pathway could be important for ischemic cardiovascular disease. METHODS: We conducted multiple independent experiments to assess whether DNA hypomethylation at F2RL3 in response to smoking is associated with risk of myocardial infarction via changes to platelet reactivity. Using cohort data (N=3205), we explored the relationship between smoking, DNA hypomethylation at F2RL3, and myocardial infarction. We compared platelet reactivity in individuals with low versus high DNA methylation at F2RL3 (N=41). We used an in vitro model to explore the biological response of F2RL3 to cigarette smoke extract. Finally, a series of reporter constructs were used to investigate how differential methylation could impact F2RL3 gene expression. RESULTS: Observationally, DNA methylation at F2RL3 mediated an estimated 34% of the smoking effect on increased risk of myocardial infarction. An association between methylation group (low/high) and platelet reactivity was observed in response to PAR4 (protease-activated receptor 4) stimulation. In cells, cigarette smoke extract exposure was associated with a 4.9% to 9.3% reduction in DNA methylation at F2RL3 and a corresponding 1.7-(95% CI, 1.2-2.4, P=0.04) fold increase in F2RL3 mRNA. Results from reporter assays suggest the exon 2 region of F2RL3 may help control gene expression. CONCLUSIONS: Smoking-induced epigenetic DNA hypomethylation at F2RL3 appears to increase PAR4 expression with potential downstream consequences for platelet reactivity. Combined evidence here not only identifies F2RL3 DNA methylation as a possible contributory pathway from smoking to cardiovascular disease risk but from any feature potentially influencing F2RL3 regulation in a similar manner.

Posttranscriptional Regulation of the Human LDL Receptor by the U2-Spliceosome.

BACKGROUND: The LDLR (low-density lipoprotein receptor) in the liver is the major determinant of LDL-cholesterol levels in human plasma. The discovery of genes that regulate the activity of LDLR helps to identify pathomechanisms of hypercholesterolemia and novel therapeutic targets against atherosclerotic cardiovascular disease. METHODS: We performed a genome-wide RNA interference screen for genes limiting the uptake of fluorescent LDL into Huh-7 hepatocarcinoma cells. Top hit genes were validated by in vitro experiments as well as analyses of data sets on gene expression and variants in human populations. RESULTS: The knockdown of 54 genes significantly inhibited LDL uptake. Fifteen of them encode for components or interactors of the U2-spliceosome. Knocking down any one of 11 out of 15 genes resulted in the selective retention of intron 3 of LDLR. The translated LDLR fragment lacks 88% of the full length LDLR and is detectable neither in nontransfected cells nor in human plasma. The hepatic expression of the intron 3 retention transcript is increased in nonalcoholic fatty liver disease as well as after bariatric surgery. Its expression in blood cells correlates with LDL-cholesterol and age. Single nucleotide polymorphisms and 3 rare variants of one spliceosome gene, RBM25, are associated with LDL-cholesterol in the population and familial hypercholesterolemia, respectively. Compared with overexpression of wild-type RBM25, overexpression of the 3 rare RBM25 mutants in Huh-7 cells led to lower LDL uptake. CONCLUSIONS: We identified a novel mechanism of posttranscriptional regulation of LDLR activity in humans and associations of genetic variants of RBM25 with LDL-cholesterol levels.

Neutrophil counts and cardiovascular disease.

BACKGROUND AND AIMS: Anti-inflammatory trials have shown considerable benefits for cardiovascular disease. High neutrophil counts, an easily accessible inflammation biomarker, are associated with atherosclerosis in experimental studies. This study aimed to investigate the associations between neutrophil counts and risk of nine cardiovascular endpoints using observational and genetic approaches. METHODS: Observational studies were conducted in the Copenhagen General Population Study (n = 101 730). Genetic studies were firstly performed using one-sample Mendelian randomization (MR) with individual-level data from the UK Biobank (n = 365 913); secondly, two-sample MR analyses were performed using summary-level data from the Blood Cell Consortium (n = 563 085). Outcomes included ischaemic heart disease, myocardial infarction, peripheral arterial disease, ischaemic cerebrovascular disease, ischaemic stroke, vascular-related dementia, vascular dementia, heart failure, and atrial fibrillation. RESULTS: Observational analyses showed associations between high neutrophil counts with high risks of all outcomes. In the UK Biobank, odds ratios (95% confidence intervals) per 1-SD higher genetically predicted neutrophil counts were 1.15 (1.08, 1.21) for ischaemic heart disease, 1.22 (1.12, 1.34) for myocardial infarction, and 1.19 (1.04, 1.36) for peripheral arterial disease; similar results were observed in men and women separately. In two-sample MR, corresponding estimates were 1.14 (1.05, 1.23) for ischaemic heart disease and 1.11 (1.02, 1.20) for myocardial infarction; multiple sensitivity analyses showed consistent results. No robust associations in two-sample MR analyses were found for other types of leucocytes. CONCLUSIONS: Observational and genetically determined high neutrophil counts were associated with atherosclerotic cardiovascular disease, supporting that high blood neutrophil counts is a causal risk factor for atherosclerotic cardiovascular disease.

Significance of lipids, lipoproteins, and apolipoproteins during the first 14-16 months of life.

BACKGROUND AND AIMS: The aims of this study were to investigate lipid parameters during the first 14-16 months of life, to identify influential factors, and to test whether high concentrations at birth predict high concentrations at 2- and 14-16 months. METHODS: The Copenhagen Baby Heart Study, including 13,354 umbilical cord blood samples and parallel venous blood samples from children and parents at birth (n = 444), 2 months (n = 364), and 14-16 months (n = 168), was used. RESULTS: Concentrations of lipids, lipoproteins, and apolipoproteins in umbilical cord blood samples correlated highly with venous blood samples from newborns. Concentrations of low-density lipoprotein (LDL) cholesterol, non-high-density lipoprotein (HDL) cholesterol, apolipoprotein B, and lipoprotein(a) increased stepwise from birth to 2 months to 14-16 months. Linear mixed models showed that concentrations of LDL cholesterol, non-HDL cholesterol, and lipoprotein(a) above the 80th percentile at birth were associated with significantly higher concentrations at 2 and 14-16 months. Finally, lipid concentrations differed according to sex, gestational age, birth weight, breastfeeding, and parental lipid concentrations. CONCLUSIONS: Lipid parameters changed during the first 14-16 months of life, and sex, gestational age, birth weight, breastfeeding, and high parental concentrations influenced concentrations. Children with high concentrations of atherogenic lipid traits at birth had higher concentrations at 2 and 14-16 months. These findings increase our knowledge of how lipid traits develop over the first 14-16 months of life and may help in deciding the optimal child age for universal familial hypercholesterolaemia screening.

Women, lipids, and atherosclerotic cardiovascular disease: a call to action from the European Atherosclerosis Society.

Cardiovascular disease is the leading cause of death in women and men globally, with most due to atherosclerotic cardiovascular disease (ASCVD). Despite progress during the last 30 years, ASCVD mortality is now increasing, with the fastest relative increase in middle-aged women. Missed or delayed diagnosis and undertreatment do not fully explain this burden of disease. Sex-specific factors, such as hypertensive disorders of pregnancy, premature menopause (especially primary ovarian insufficiency), and polycystic ovary syndrome are also relevant, with good evidence that these are associated with greater cardiovascular risk. This position statement from the European Atherosclerosis Society focuses on these factors, as well as sex-specific effects on lipids, including lipoprotein(a), over the life course in women which impact ASCVD risk. Women are also disproportionately impacted (in relative terms) by diabetes, chronic kidney disease, and auto-immune inflammatory disease. All these effects are compounded by sociocultural components related to gender. This panel stresses the need to identify and treat modifiable cardiovascular risk factors earlier in women, especially for those at risk due to sex-specific conditions, to reduce the unacceptably high burden of ASCVD in women.

Plasma Concentrations of Calcium and Risk of Alzheimer Disease-Observational and Genetic Studies.

BACKGROUND: Dysregulation of calcium ion homeostasis in neurons is well documented in Alzheimer disease (AD), and high plasma calcium concentrations have been associated with cognitive decline in the elderly; however, a potential causal nature for this association has not been elucidated. METHODS: Plasma calcium ion concentrations of 97 968 individuals from the Copenhagen General Population Study (CGPS) were included and multifactorial Cox regressions using splines or quartiles was performed to investigate the observational association. A plasma calcium ion genome-wide association study (GWAS) was performed in 2 independent subgroups of the CGPS. The plasma calcium ion GWAS and publicly available genomic data sets for plasma total calcium and AD were used to perform the currently most powerful 2-sample Mendelian randomization studies. RESULTS: The hazard ratio for lowest vs highest quartile of the calcium ion concentration was 1.24 (95% CI, 1.08-1.43) for AD. The plasma calcium ion GWAS identified 3 independent loci. None of the genetic instruments for plasma concentrations of calcium ions or total calcium were associated with AD risk. CONCLUSIONS: High plasma concentrations of calcium ions were observationally associated with increased risk of AD but genetic associations were not found, suggesting that the observational findings may be due to reverse causation or residual confounding.

Genetic risk of fatty liver disease and mortality in the general population: A Mendelian randomization study.

BACKGROUND & AIMS: Fatty liver disease has been associated with higher all-cause as well as liver-related, ischemic heart disease (IHD)-related and extrahepatic cancer-related mortality in observational epidemiological studies. We tested the hypothesis that fatty liver disease is a causal risk factor for higher mortality. METHODS: We genotyped seven genetic variants known to be associated with fatty liver disease (in PNPLA3, TM6SF2, HSD17B13, MTARC1, MBOAT7, GCKR, and GPAM) in 110 913 individuals from the Danish general population. Hepatic steatosis was measured by hepatic computed tomography in n = 6965. Using a Mendelian randomization framework, we tested whether genetically proxied hepatic steatosis and/or elevated plasma alanine transaminase (ALT) was associated with liver-related mortality. RESULTS: During a median follow-up of 9.5 years, 16 119 individuals died. In observational analyses, baseline elevated plasma ALT was associated with higher all-cause (1.26-fold), liver-related (9-fold), and extrahepatic cancer-related (1.25-fold) mortality. In genetic analyses, the risk alleles in PNPLA3, TM6SF2, and HSD17B13 were individually associated with higher liver-related mortality. The largest effects were seen for the PNPLA3 and TM6SF2 risk alleles, for which homozygous carriers had 3-fold and 6-fold, respectively, higher liver-related mortality than non-carriers. None of the risk alleles, individually or combined into risk scores, were robustly associated with all-cause, IHD-related, or extrahepatic cancer-related mortality. In instrumental variable analyses, genetically proxied hepatic steatosis and higher plasma ALT were associated with liver-related mortality. CONCLUSIONS: Human genetic data support that fatty liver disease is a causal driver of liver-related mortality.

Variants in the GPR146 Gene Are Associated With a Favorable Cardiometabolic Risk Profile.

BACKGROUND: In mice, GPR146 (G-protein-coupled receptor 146) deficiency reduces plasma lipids and protects against atherosclerosis. Whether these findings translate to humans is unknown. METHODS: Common and rare genetic variants in the GPR146 gene locus were used as research instruments in the UK Biobank. The Lifelines, The Copenhagen-City Heart Study, and a cohort of individuals with familial hypobetalipoproteinemia were used to find and study rare GPR146 variants. RESULTS: In the UK Biobank, carriers of the common rs2362529-C allele present with lower low-density lipoprotein cholesterol, apo (apolipoprotein) B, high-density lipoprotein cholesterol, apoAI, CRP (C-reactive protein), and plasma liver enzymes compared with noncarriers. Carriers of the common rs1997243-G allele, associated with higher GPR146 expression, present with the exact opposite phenotype. The associations with plasma lipids of the above alleles are allele dose-dependent. Heterozygote carriers of a rare coding variant (p.Pro62Leu; n=2615), predicted to be damaging, show a stronger reductions in the above parameters compared with carriers of the common rs2362529-C allele. The p.Pro62Leu variant is furthermore shown to segregate with low low-density lipoprotein cholesterol in a family with familial hypobetalipoproteinemia. Compared with controls, carriers of the common rs2362529-C allele show a marginally reduced risk of coronary artery disease (P=0.03) concomitant with a small effect size on low-density lipoprotein cholesterol (average decrease of 2.24 mg/dL in homozygotes) of this variant. Finally, mendelian randomization analyses suggest a causal relationship between GPR146 gene expression and plasma lipid and liver enzyme levels. CONCLUSIONS: This study shows that carriers of new genetic GPR146 variants have a beneficial cardiometabolic risk profile, but it remains to be shown whether genetic or pharmaceutical inhibition of GPR146 protects against atherosclerosis in humans.

Genetic variants in the adenosine triphosphate-binding cassette transporter A1 and risk of age-related macular degeneration.

Genetic variants in ABCA1 are associated with higher concentrations of high-density lipoprotein (HDL) cholesterol. Higher HDL cholesterol concentrations are observationally and genetically associated with higher risk of age-related macular degeneration (AMD). However, whether amino acid-changing genetic variants in ABCA1 associated with high HDL cholesterol concentrations confer a higher risk of AMD in the general population is currently unknown. We tested this hypothesis. The study included 80,972 individuals (1,370 AMD cases) from the Copenhagen General Population Study (CGPS) and 9,584 individuals (142 AMD cases) from the Copenhagen City Heart Study (CCHS) with 10 to 18 years of follow-up. We created an HDL cholesterol weighted allele score based on amino acid-changing ABCA1 variants with a minor allele frequency above 0.001 and divided it into tertiles. The study included 55% women. Mean age was 58 years. The ABCA1 allele score for the third versus the first tertile was associated with HRs (95% confidence intervals (CIs)) of 1.30 (1.14-1.49) for all-cause AMD, 1.26 (1.06-1.50) for nonneovascular AMD, and 1.31 (1.12-1.53) for neovascular AMD in a multivariable adjusted model. On a continuous scale, higher concentrations of genetically determined HDL cholesterol were associated with higher risk of all-cause AMD, nonneovascular AMD, and neovascular AMD in an age- and sex adjusted model and in a multivariable adjusted model. In conclusion, amino acid-changing genetic variants in ABCA1 associated with higher HDL cholesterol concentrations were also associated with higher risk of AMD, suggesting a role for ABCA1 in AMD pathogenesis.

The European Heart Journal: fulfilling the mission.

In September 2020, the new Editors of the European Heart Journal (EHJ) wrote the following in their inaugural editorial: "The fundamental mission of the Journal remains the reduction of the global burden of cardiovascular disease. We aspire to advance this aim by worldwide teamwork to communicate practice-changing research, inspire clinical cardiologists, and pursue rigour and transparency in the application of science at the service of human health. The Journal will strive to lead the field in its impact, influence, and reach". After more than one year of experience the Editors hope the cardiological community will agree that they are fulfilling this mission. As stewards of the EHJ, the Editor's primary goal is not solely to achieve a high Impact Factor (which attests to the scientific quality and influence of our publications) but also to elevate the practice of cardiovascular medicine worldwide. Accordingly, various initiatives of the EHJ strive to strengthen further links among Editors, Authors, Reviewers and Readers through a series of coordinated and diverse activities, including webinars, active social media presence, and active participation at congresses worldwide. The Editors are proud to serve one of the most important scientific journals in cardiovascular medicine.

Inhibition of Cholesteryl Ester Transfer Protein Preserves High-Density Lipoprotein Cholesterol and Improves Survival in Sepsis.

BACKGROUND: The high-density lipoprotein hypothesis of atherosclerosis has been challenged by clinical trials of cholesteryl ester transfer protein (CETP) inhibitors, which failed to show significant reductions in cardiovascular events. Plasma levels of high-density lipoprotein cholesterol (HDL-C) decline drastically during sepsis, and this phenomenon is explained, in part, by the activity of CETP, a major determinant of plasma HDL-C levels. We tested the hypothesis that genetic or pharmacological inhibition of CETP would preserve high-density lipoprotein levels and decrease mortality in clinical cohorts and animal models of sepsis. METHODS: We examined the effect of a gain-of-function variant in CETP (rs1800777, p.Arg468Gln) and a genetic score for decreased CETP function on 28-day sepsis survival using Cox proportional hazard models adjusted for age and sex in the UK Biobank (n=5949), iSPAAR (Identification of SNPs Predisposing to Altered Acute Lung Injury Risk; n=882), Copenhagen General Population Study (n=2068), Copenhagen City Heart Study (n=493), Early Infection (n=200), St Paul's Intensive Care Unit 2 (n=203), and Vasopressin Versus Norepinephrine Infusion in Patients With Septic Shock studies (n=632). We then studied the effect of the CETP inhibitor, anacetrapib, in adult female APOE*3-Leiden mice with or without human CETP expression using the cecal-ligation and puncture model of sepsis. RESULTS: A fixed-effect meta-analysis of all 7 cohorts found that the CETP gain-of-function variant was significantly associated with increased risk of acute sepsis mortality (hazard ratio, 1.44 [95% CI, 1.22-1.70]; P<0.0001). In addition, a genetic score for decreased CETP function was associated with significantly decreased sepsis mortality in the UK Biobank (hazard ratio, 0.77 [95% CI, 0.59-1.00] per 1 mmol/L increase in HDL-C) and iSPAAR cohorts (hazard ratio, 0.60 [95% CI, 0.37-0.98] per 1 mmol/L increase in HDL-C). APOE*3-Leiden.CETP mice treated with anacetrapib had preserved levels of HDL-C and apolipoprotein-AI and increased survival relative to placebo treatment (70.6% versus 35.3%, Log-rank P=0.03), whereas there was no effect of anacetrapib on the survival of APOE*3-Leiden mice that did not express CETP (50.0% versus 42.9%, Log-rank P=0.87). CONCLUSIONS: Clinical genetics and humanized mouse models suggest that inhibiting CETP may preserve high-density lipoprotein levels and improve outcomes for individuals with sepsis.

Triglyceride-rich lipoproteins and their remnants: metabolic insights, role in atherosclerotic cardiovascular disease, and emerging therapeutic strategies-a consensus statement from the European Atherosclerosis Society.

Recent advances in human genetics, together with a large body of epidemiologic, preclinical, and clinical trial results, provide strong support for a causal association between triglycerides (TG), TG-rich lipoproteins (TRL), and TRL remnants, and increased risk of myocardial infarction, ischaemic stroke, and aortic valve stenosis. These data also indicate that TRL and their remnants may contribute significantly to residual cardiovascular risk in patients on optimized low-density lipoprotein (LDL)-lowering therapy. This statement critically appraises current understanding of the structure, function, and metabolism of TRL, and their pathophysiological role in atherosclerotic cardiovascular disease (ASCVD). Key points are (i) a working definition of normo- and hypertriglyceridaemic states and their relation to risk of ASCVD, (ii) a conceptual framework for the generation of remnants due to dysregulation of TRL production, lipolysis, and remodelling, as well as clearance of remnant lipoproteins from the circulation, (iii) the pleiotropic proatherogenic actions of TRL and remnants at the arterial wall, (iv) challenges in defining, quantitating, and assessing the atherogenic properties of remnant particles, and (v) exploration of the relative atherogenicity of TRL and remnants compared to LDL. Assessment of these issues provides a foundation for evaluating approaches to effectively reduce levels of TRL and remnants by targeting either production, lipolysis, or hepatic clearance, or a combination of these mechanisms. This consensus statement updates current understanding in an integrated manner, thereby providing a platform for new therapeutic paradigms targeting TRL and their remnants, with the aim of reducing the risk of ASCVD.

C-reactive protein levels and risk of dementia-Observational and genetic studies of 111,242 individuals from the general population.

INTRODUCTION: Increased plasma levels of C-reactive protein (CRP) in midlife are associated with increased risk of Alzheimer's disease (AD), whereas in older age the opposite association is observed. Whether genetically determined CRP is associated with AD remains unclear. METHODS: A total of 111,242 White individuals from the Copenhagen General Population Study and the Copenhagen City Heart Study were included. Plasma levels of CRP and four regulatory genetic variants in the CRP gene were determined. RESULTS: For CRP percentile group 1 to 5 (lowest plasma CRP) versus the 50 to 75 group (reference), the hazard ratio for AD was 1.69 (95% confidence interval 1.29-2.16). Genetically low CRP was associated with increased risk of AD in individuals with body mass index ≤25 kg/m2 (P = 4 × 10-6 ). DISCUSSION: Low plasma levels of CRP at baseline were associated with high risk of AD in individuals from the general population. These observational findings were supported by genetic studies.

Polygenic risk scores: how much do they add?

PURPOSE OF REVIEW: Current methods to assess genetic risk of familial hypercholesterolemia and coronary artery disease (CAD) focus on testing monogenic mutations in well known genes. Here we review recent developments in polygenic risk scores (PRSs) for LDL cholesterol and for CAD, and how they may add to current risk prediction algorithms. RECENT FINDINGS: PRSs can identify 10-20 times as many individuals at high polygenic risk compared with monogenic mutations, and PRSs can modulate the effect of a monogenic variant on risk. Current risk factor prediction tools for prevention of CAD incompletely capture polygenic susceptibility, and PRSs may identify subgroups of patients who are likely to benefit more from lipid-lowering therapy. Finally, PRSs can be quantified already at birth, long before other risk factors used to predict CAD, and before clinical manifestations of disease. SUMMARY: PRSs for CAD may soon be incorporated into clinical practice. Therefore, there is an urgent need to establish both analytical and clinical reporting standards for PRSs, and for validating scores in different ethnicities. Thresholds for intervention need to be established for PRSs and integrated into established risk scores. Training programs are needed for clinical staff to learn to communicate polygenic risk in a comprehensive way to the patient.

Impact of high glucose levels and glucose lowering on risk of ischaemic stroke: a Mendelian randomisation study and meta-analysis.

AIMS/HYPOTHESIS: It is unclear whether glucose per se has a causal impact on risk of stroke and whether glucose-lowering drugs reduce this risk. This is important for the choice of treatment for individuals at risk. We tested the hypotheses that high plasma glucose has a causal impact on increased risk of ischaemic stroke, and that glucose-lowering drugs reduce this risk. METHODS: Using a Mendelian randomisation design, we examined 118,838 individuals from two Copenhagen cohorts, the Copenhagen General Population Study and the Copenhagen City Heart Study, and 440,328 individuals from the MEGASTROKE study. Effects of eight glucose-lowering drugs on risk of stroke were summarised by meta-analyses. RESULTS: In genetic, causal analyses, a 1 mmol/l higher plasma glucose had a risk ratio of 1.48 (95% CI 1.04, 2.11) for ischaemic stroke in the Copenhagen studies. The corresponding risk ratio from the MEGASTROKE study combined with the Copenhagen studies was 1.74 (1.31, 2.18). In meta-analyses of glucose-lowering drugs, the risk ratio for stroke was 0.85 (0.77, 0.94) for glucagon-like peptide-1 receptor agonists and 0.82 (0.69, 0.98) for thiazolidinediones, while sulfonylureas, dipeptidyl peptidase-4 inhibitors, sodium-glucose cotransporter 2 inhibitors, α-glucosidase inhibitors, meglitinides and metformin individually lacked statistical evidence of an effect on stroke risk. CONCLUSIONS/INTERPRETATION: Genetically high plasma glucose has a causal impact on increased risk of ischaemic stroke. Treatment with glucose-lowering glucagon-like peptide-1 receptor agonists and thiazolidinediones reduces this risk. These results may guide clinicians in the treatment of individuals at high risk of ischaemic stroke.

Genetic Variants Associated With Increased Plasma Levels of Triglycerides, via Effects on the Lipoprotein Lipase Pathway, Increase Risk of Acute Pancreatitis.

BACKGROUND & AIMS: Almost one third of adults in the West have increased plasma levels of triglycerides. Even mild to moderate hypertriglyceridemia (2-10 mmol/L or 177-886 mg/dL) is associated with an increased risk of acute pancreatitis. However, it is not clear whether hypertriglyceridemia is a cause or result of acute pancreatitis. Lipoprotein lipase degrades plasma triglycerides. Variants in LPL, APOA5, APOC3, ANGPTL3, and ANGPTL4, which regulate the lipoprotein lipase pathway, result in increased or reduced plasma triglyceride levels. We investigated associations between these variants and acute pancreatitis in a study of the general population. METHODS: In a prospective cohort study, men and women randomly selected from the area of Copenhagen were invited to complete a questionnaire, undergo a physical examination, and provide blood samples for biochemical and genetic analyses, from 2003 through 2015. We obtained triglyceride measurements from 117,427 participants. We examined for 15 genetic variants that are associated with lipoprotein lipase function in DNA samples from 102,888 participants and analyzed data from 117,427 participants in observational analyses. Diagnoses of acute pancreatitis (970 diagnoses among participants in the genetic analysis and 527 among participants in the observational study) were obtained from Danish registries. We performed a 1-sample Mendelian randomization analysis in which specific variants were used as markers of the plasma level of triglycerides to determine the association between the plasma level of triglyceride and acute pancreatitis. We calculated unweighted, internally weighted, and externally weighted allele scores for each participant by adding numbers of triglyceride-increasing alleles. RESULTS: The highest genetic allele score correlated with a higher plasma level of triglycerides of 0.54 mmol/L (48 mg/dL). Among participants with the highest vs the lowest genetic allele score, the odds ratio for acute pancreatitis was 1.55 (95% CI, 1.08-2.23). Using instrumental variable analysis, integrating the effect of genotype on both triglycerides levels and risk of acute pancreatitis, we associated higher unweighted allele scores with an increased risk of acute pancreatitis (odds ratio [OR], 1.76; 95% CI, 1.16-2.65), as well as internally weighted higher allele scores (OR, 1.41; 95% CI, 1.01-1.97) and externally weighted higher allele scores (OR, 1.44; 95% CI, 1.01-2.04). Every 1 mmol/L (89 mg/dL) increase in triglycerides was observationally associated with an increase in OR of 1.09 (95% CI, 1.05-1.14) after multivariable adjustment. CONCLUSIONS: Based on an analysis of individuals with genetic variants associated with an increased level of triglycerides, via their effects on the lipoprotein lipase pathway, we associated an increased plasma levels of triglycerides with an increased risk of acute pancreatitis. Strategies to reduce plasma levels of triglycerides, by increasing lipoprotein lipase function, might be developed for prevention of acute pancreatitis.

Plasma Concentrations of Magnesium and Risk of Dementia: A General Population Study of 102 648 Individuals.

BACKGROUND: Low and high concentrations of plasma magnesium are associated with increased risk of future all-cause dementia; however, the underlying reasons remain elusive. The magnesium ion is an important electrolyte serving as a cofactor in many enzymatic processes in the human organism. Magnesium affects both neuronal and vascular functions. We investigated the associations of plasma concentrations of magnesium associate with common subtypes of dementia as Alzheimer dementia and non-Alzheimer dementia, and potential pathways by which magnesium may affect risk of dementia. METHODS: Plasma concentrations of magnesium were measured in 102 648 individuals from the Copenhagen General Population Study. Cox regression and natural effects mediation analyses evaluated associations with either Alzheimer dementia or non-Alzheimer dementia. RESULTS: Multifactorially adjusted hazard ratios for non-Alzheimer dementia were 1.50(95% confidence interval (CI):1.21-1.87) for the lowest and 1.34(1.07-1.69) for the highest vs the fourth quintile (reference) of plasma magnesium concentrations. Diabetes, cumulated smoking, stroke, and systolic blood pressure mediated 10.4%(3.1-22.8%), 6.8%(1.2-14.0%), 1.3%(0.1-3.6%), and 1.0%(0.2-2.6%), respectively, in the lowest quintile, whereas stroke mediated 3.2%(0.4-11.9%) in the highest quintile. No associations were observed for Alzheimer dementia. CONCLUSIONS: Low and high plasma magnesium concentrations were associated with high risk of vascular-related non-Alzheimer dementia, with the lowest risk observed at a concentration of 2.07 mg/dL (0.85 mmol/L). No association was observed for Alzheimer dementia. Mediation analysis suggested that diabetes may be in the causal pathway between low plasma magnesium concentrations and high risk of non-Alzheimer dementia, while cumulated smoking, stroke, and systolic blood pressure played minor mediating roles.

Triglycerides as a Shared Risk Factor between Dementia and Atherosclerotic Cardiovascular Disease: A Study of 125 727 Individuals.

BACKGROUND: Risk factors for atherosclerotic cardiovascular disease such as smoking, hypertension, physical inactivity, and diabetes have also been associated with risk of dementia. Whether hypertriglyceridemia represents a shared risk factor as well remains unknown. We tested the hypothesis that hypertriglyceridemia is associated with increased risk of non-Alzheimer dementia, Alzheimer disease, and ischemic stroke. METHODS: Using the Copenhagen General Population Study and the Copenhagen City Heart Study, we examined the association between increased plasma triglycerides and risk of non-Alzheimer dementia, Alzheimer disease, and ischemic stroke with Cox regression. RESULTS: On a continuous scale, higher concentrations of plasma triglycerides were associated with increased risk of non-Alzheimer dementia and ischemic stroke, but not with Alzheimer disease. In age, sex, and cohort adjusted models, the highest percentile of triglycerides (median 629 mg/dL; 7.1 mmol/L) versus the 1-50th percentiles (median 89 mg/dL; 1.0 mmol/L) was associated with hazard ratios of 1.75 (95% confidence interval: 1.17-2.63) for non-Alzheimer dementia, 1.18 (0.73-1.91) for Alzheimer disease, and of 1.89 (1.50-2.38) for ischemic stroke. Corresponding hazard ratios were 1.62 (1.08-2.44), 1.25 (0.77-2.02), and 1.57 (1.24-1.98) in models adjusted multifactorially, and 1.79 (1.16-2.87), 1.18 (0.73-1.92), and 1.46 (1.10-1.95) in models adjusted multifactorially and additionally for apolipoprotein E (APOE) genotype, respectively. Results were similar after excluding individuals who had an event within 2 years after study entry. CONCLUSIONS: Moderate hypertriglyceridemia was associated with increased risk of both non-Alzheimer dementia and ischemic stroke, highlighting plasma triglycerides as a shared risk factor between dementia and atherosclerotic cardiovascular disease.

High Risk of Fatty Liver Disease Amplifies the Alanine Transaminase-Lowering Effect of a HSD17B13 Variant.

A common loss-of-function variant in HSD17B13 (rs72613567:TA) was recently found to protect from chronic liver disease. Whether the variant confers protection from specific risk factors for liver disease is unclear. We tested the association of rs72613567 with plasma levels of alanine transaminase (ALT) and clinical liver disease and mortality in 111,612 individuals from the Danish general population, including 497 with cirrhosis and 113 with hepatocellular carcinoma. HSD17B13 rs72613567:TA was associated with stepwise lower levels of plasma ALT of up to 1.3 U/L in TA/TA homozygotes versus T/T homozygotes. For each TA-allele, the risk of cirrhosis and hepatocellular carcinoma was reduced by 15% and 28%, respectively. In prospective analyses, the TA-allele was associated with up to 33% lower rates of liver-related mortality in the general population, and with up to 49% reduced liver-related mortality in patients with cirrhosis. The ALT-lowering effect of rs72613567:TA was amplified by increasing adiposity, alcohol consumption, and genetic risk of fatty liver disease. The TA-allele was associated with only marginally lower ALT in lean nondrinkers with low genetic risk of hepatic steatosis. In contrast, compared with T/T homozygotes, TA/TA homozygotes had 12% to 18% lower plasma ALT among the most obese, in heavy drinkers, and in individuals carrying three or four steatogenic alleles in patatin-like phospholipase domain-containing protein 3 (PNPLA3) and transmembrane 6 superfamily 2 (TM6SF2). Conclusion: High risk of fatty liver disease amplifies the ALT-lowering effect of HSD17B13 rs72613567:TA in the Danish general population.

Combined Effect of PNPLA3, TM6SF2, and HSD17B13 Variants on Risk of Cirrhosis and Hepatocellular Carcinoma in the General Population.

BACKGROUND AND AIMS: We hypothesized that a genetic risk score (GRS) for fatty liver disease influences the risk of cirrhosis and hepatocellular carcinoma (HCC). Three genetic variants (patatin-like phospholipase domain-containing protein 3 [PNPLA3] p.I148M; transmembrane 6, superfamily member 2 [TM6SF2] p.E167K; and hydroxysteroid 17-beta dehydrogenase 13 [HSD17B13] rs72613567) were combined into a risk score, ranging from 0 to 6 for risk-increasing alleles. APPROACH AND RESULTS: We examined the association of the risk score with plasma markers of liver disease and with cirrhosis and HCC in 110,761 individuals from Copenhagen, Denmark, and 334,691 individuals from the UK Biobank. The frequencies of risk scores of 0, 1, 2, 3, 4, and 5 or 6 were 5%, 25%, 41%, 23%, 5.5%, and 0.5%, respectively. A higher GRS was associated with an increase in plasma alanine aminotransferase (ALT) level of 26% in those with score 5 or 6 versus 0. In meta-analysis of the Copenhagen studies and the UK Biobank, individuals with scores 1, 2, 3, 4, and 5 or 6 had odds ratios (ORs) for cirrhosis of 1.6 (95% confidence interval [CI], 1.3, 1.9), 2.0 (95% CI, 1.8, 2.2), 3.1 (95% CI, 2.7, 3.5), 5.2 (95% CI, 4.2, 6.4), and 12 (95% CI, 7.7, 19), respectively, as compared with those with a score of 0. The corresponding ORs for HCC were 1.2 (95% CI, 0.9, 1.7), 1.0 (95% CI, 0.7, 1.3), 2.4 (95% CI, 1.9, 3.0), 3.3 (95% CI, 2.2, 5.0), and 29 (95% CI, 17, 51). CONCLUSION: A GRS for fatty liver disease confers up to a 12-fold higher risk of cirrhosis and up to a 29-fold higher risk of HCC in individuals from the general population.