Background: Venous thromboembolism (VTE) is a life-threatening vascular event with environmental and genetic determinants. Recent VTE genome-wide association studies (GWAS) meta-analyses involved... Show moreBackground: Venous thromboembolism (VTE) is a life-threatening vascular event with environmental and genetic determinants. Recent VTE genome-wide association studies (GWAS) meta-analyses involved nearly 30 000 VTE cases and identified up to 40 genetic loci associated with VTE risk, including loci not previously suspected to play a role in hemostasis. The aim of our research was to expand discovery of new genetic loci associated with VTE by using cross-ancestry genomic resources. Methods: We present new cross-ancestry meta-analyzed GWAS results involving up to 81 669 VTE cases from 30 studies, with replication of novel loci in independent populations and loci characterization through in silico genomic interrogations. Results: In our genetic discovery effort that included 55 330 participants with VTE (47 822 European, 6320 African, and 1188 Hispanic ancestry), we identified 48 novel associations, of which 34 were replicated after correction for multiple testing. In our combined discovery-replication analysis (81 669 VTE participants) and ancestry-stratified meta-analyses (European, African, and Hispanic), we identified another 44 novel associations, which are new candidate VTE-associated loci requiring replication. In total, across all GWAS meta-analyses, we identified 135 independent genomic loci significantly associated with VTE risk. A genetic risk score of the significantly associated loci in Europeans identified a 6-fold increase in risk for those in the top 1% of scores compared with those with average scores. We also identified 31 novel transcript associations in transcriptome-wide association studies and 8 novel candidate genes with protein quantitative-trait locus Mendelian randomization analyses. In silico interrogations of hemostasis and hematology traits and a large phenome-wide association analysis of the 135 GWAS loci provided insights to biological pathways contributing to VTE, with some loci contributing to VTE through well-characterized coagulation pathways and others providing new data on the role of hematology traits, particularly platelet function. Many of the replicated loci are outside of known or currently hypothesized pathways to thrombosis. Conclusions: Our cross-ancestry GWAS meta-analyses identified new loci associated with VTE. These findings highlight new pathways to thrombosis and provide novel molecules that may be useful in the development of improved antithrombosis treatments. Show less
Morelli, V.M.; Mutsert, R. de; Roos, A. de; Lamb, H.J.; Vlieg, A.V.; Bos, M.H.A.; ... ; Cannegieter, S.C. 2020
Objective:Whether hepatic triglyceride content (HTGC) contributes to hypercoagulability beyond total body fat (TBF) and visceral adipose tissue (VAT) is unclear. We, therefore, aimed to investigate... Show moreObjective:Whether hepatic triglyceride content (HTGC) contributes to hypercoagulability beyond total body fat (TBF) and visceral adipose tissue (VAT) is unclear. We, therefore, aimed to investigate the association between HTGC and coagulation factors (F)I (fibrinogen), VIII, IX, and XI while adjusting for TBF and VAT.Approach and Results:In this cross-sectional analysis of the NEO study (Netherlands Epidemiology of Obesity; n=6671), a random subset of participants underwent magnetic resonance imaging and magnetic resonance spectroscopy to assess VAT and HTGC (n=2580). We excluded participants without complete imaging and coagulation assessment, and with history of liver disease, venous thrombosis, or on anticoagulation. Mean differences in coagulation factor levels across HTGC quartiles were estimated by linear regression adjusted for age, sex, ethnicity, education, alcohol intake, physical activity, smoking, estrogen, and menopause, in addition to TBF and VAT. Among the 1946 participants included, median HTGC was 2.66% (interquartile range: 1.34%-6.27%). Coagulation factor levels increased dose-dependently across HTGC quartiles. Mean differences between the fourth and first quartiles were 14.7 mg/dL (95% CI, 2.1-27.2) for fibrinogen, 6.7 IU/dL (95% CI, 0.5-12.9) for FVIII, 26.1 IU/dL (95% CI, 22.4-29.8) for FIX, and 8.6 IU/dL (95% CI, 4.6-12.6) for FXI. With further adjustment for TBF and VAT, the dose-response association of HTGC with FIX persisted, whereas associations with other factors disappeared.Conclusions:HTGC was associated with various coagulation factors, of which FIX remained associated with HTGC after adjustment for TBF and VAT. HTGC might contribute to venous thrombosis risk beyond total body and visceral fat through FIX levels. Show less
Background Family history of myocardial infarction (FHMI) is known to increase the risk of venous thromboembolism (VTE). Objectives To investigate the effect of prothrombotic genotypes on the... Show moreBackground Family history of myocardial infarction (FHMI) is known to increase the risk of venous thromboembolism (VTE). Objectives To investigate the effect of prothrombotic genotypes on the association between FHMI and VTE in a case-cohort recruited from a general population. Methods Cases with a first VTE (n = 1493) and a subcohort (n = 13 072) were sampled from the Tromso study (1994-2012) and the Nord-Trondelag health (HUNT) study (1995-2008). The DNA samples were genotyped for rs8176719 (ABO), rs6025 (F5), rs1799963 (F2), rs2066865 (FGG), and rs2036914 (F11). Participants with missing information on risk alleles (n = 175), FHMI (n = 2769), and BMI (n = 52) were excluded. Cox regression models were used to estimate hazard ratios (HRs) with 95% confidence intervals (CI) for VTE. To explore the role of prothrombotic genotypes for the association between FHMI and VTE, we (a) included the genotypes in the multivariable-adjusted models and (b) assessed the joint effects between FHMI and genotypes on VTE risk. Results The FHMI was associated with a 1.3-fold increased risk of VTE (HR 1.32, 95% CI 1.16-1.50) and 1.5-fold increased risk of unprovoked VTE (HR 1.47, 95% CI 1.22-1.78). The risk of VTE by FHMI did not alter after adjustment for the five genotypes. The combination of FHMI and the different prothrombotic genotypes did not result in an excess VTE risk (i.e. no biological interaction). Conclusions Our findings suggest that the risk of VTE by FHMI is not explained by rs8176719 (ABO), rs6025 (F5), rs1799963 (F2), rs2066865 (FGG), and rs2036914 (F11). The combination of FHMI with prothrombotic genotypes had an additive effect on VTE risk. Show less
Several studies during the past decade have shown that patients with venous thrombosis have an increased risk of subsequent arterial thrombosis, thus suggesting a link between the two diseases. The... Show moreSeveral studies during the past decade have shown that patients with venous thrombosis have an increased risk of subsequent arterial thrombosis, thus suggesting a link between the two diseases. The aim of this thesis was to investigate the associations of traditional cardiometabolic risk factors with risk of a first and recurrent venous thrombosis. We showed that levels of major lipids, i.e. total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides, were not associated with a first venous thrombosis. In contrast, low levels of apolipoproteins B and A1 were associated with an increased risk of a first event. Regarding recurrence, tests for lipid levels, glucose levels and hematologic variables did not identify patients at an increased risk of recurrent venous thrombosis, and these tests should not be done for this indication nor influence decisions on duration of anticoagulant treatment. In this thesis, we further searched for associations between lipids and hemostatic factors, and found that levels of vitamin K-dependent factors (VKDFs), including factor IX, were associated with triglyceride levels. We hypothesized that this association could be explained by common mechanisms, regulating levels of both VKDFs and triglycerides. Show less
