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• Venous thromboembolism (VTE) is a major cause of mortality and morbidity worldwide. • Data on VTE patients was extracted from the Norwegian Patient Registry. • Recently the incidence and prevalence of VTE in Norway has been relatively stable. • The incidence of PE has increased, whereas DVT incidence has decreased slightly. [ABSTRACT FROM AUTHOR]

Objective: The relationship between serum levels of calcium, parathyroid hormone (PTH) and risk of venous thromboembolism (VTE) has not been addressed in population-based cohorts. We investigated the associations between serum levels of calcium and PTH, with future risk of VTE in a general adult population. Design: Population-based cohort. Methods: A total of 27 712 subjects (25–87 years) who participated in Tromsø 4 (1994–1995) and Tromsø 5 (2001–2002) surveys were included in the study, and total calcium and PTH were measured in 27 685 and 8547 subjects respectively. Incident VTE was recorded through December 31, 2012. Cox-regression models with calcium and PTH as time-varying exposures were used to calculate hazard ratios (HR) of VTE by quartiles of calcium and PTH. Quartiles of calcium and PTH were also combined to assess the effect of discordants of both PTH and calcium (e.g. highest and lowest quartiles of both calcium and PTH) on VTE risk using the middle two quartiles as reference. Results: There were 712 VTEs during 15.0 years of median follow-up. Serum levels of calcium and PTH were not associated with risk of VTE. However, subjects with discordant high serum levels of both calcium and PTH (calcium ≥2.45 mmol/L and PTH ≥4.0 pmol/L) had increased risk of VTE compared to those in subjects with normal calcium and PTH (multivariable HR: 1.78, 95% CI: 1.12–2.84). Conclusions: Serum levels of calcium and PTH separately were not associated with future risk of VTE, but subjects with high levels of both calcium and PTH had increased risk of VTE compared to those in subjects with normal levels. [ABSTRACT FROM AUTHOR]

Background: Serum osteoprotegerin (OPG) is elevated in patients with chronic kidney disease (CKD) and increases with decreasing renal function. However, there are limited data regarding the association between OPG and renal function in the general population. The aim of the present study was to explore the relation between serum OPG and renal function in subjects recruited from the general population. Methods: We conducted a cross-sectional study with 6689 participants recruited from the general population in Tromsø, Norway. Estimated glomerular filtration rate (eGFR) was calculated using the Chronic Kidney Disease Epidemiology Collaboration equations. OPG was modelled both as a continuous and categorical variable. General linear models and linear regression with adjustment for possible confounderswere used to study the association between OPG and eGFR. Analyseswere stratified by the median age, as serum OPG and age displayed a significant interaction on eGFR. Results: In participants ≤62.2 years with normal renal function (eGFR ≥90 mL/min/1.73m2) eGFR increased by 0.35 mL/min/1.73m2 (95% CI 0.13-0.56) per 1 standard deviation (SD) increase in serum OPG after multiple adjustment. In participants older than the median age with impaired renal function (eGFR <90 mL/min/1.73m2), eGFR decreased by 1.54 (95% CI - 2.06 to - 1.01) per 1 SD increase in serum OPG. Conclusions: OPGwas associated with an increased eGFR in younger subjects with normal renal function and with a decreased eGFR in older subjects with reduced renal function. Our findings imply that the association between OPG and eGFR varies with age and renal function. [ABSTRACT FROM AUTHOR]

Men have a higher incidence of cardiovascular disease (CVD) than women, and adverse thrombotic events increase with age. Recent experimental cross-sectional, and case-control studies have shown that testosterone may affect the hemostatic/fibrinolytic system in men in several ways. It has been hypothesized that physiological doses of testosterone would have a beneficial effect on tissue factor-induced thrombin generation and the development of CVD. The search for eternal youth has created a market for testosterone treatment in aging men during the last few years. However, whether testosterone supplementation could be useful in the treatment of testosterone-deficient elderly men is still controversial. The present review focuses on the coagulation system and CVD from the perspective of testosterone. [ABSTRACT FROM AUTHOR]

Platelet microparticles (PMPs) are highly procoagulant and might therefore be important in the pathogenesis of arterial thrombotic diseases. The aim of this study was to determine plasma levels of PMPs in survivors of myocardial infarction (MI) and their relation to activation of primary (sCD40L) and secondary (thrombin-antithrombin (TAT) complexes) haemostasis. An observational, population-based case control study was conducted in 61 MI patients 1-4 years after the MI and 61 age-matched and sex-matched healthy controls. PMPs were quantified using an immunoassay that discriminates between small and large PMPs. MI patients had significantly higher total PMPs (314.3 µg/L, 273.1-361.4 µg/L versus 225.8 µg/L, 168.8-273.1 µg/L, p = 0.009) (geometric mean and 95% CI) and larger PMPs (181.3 µg/L, 160.7-204.3 µg/L versus 134.3 µg/L, 104.6-174.9 µg/L) than controls. The differences between groups remained significant after adjustments for use of cardiovascular drugs, body mass index, blood pressure and serum lipids, but were weakened when smoking was included in the analysis. Multiple regression analysis revealed a significant independent association between large PMPs and plasma TAT and soluble CD40 ligand (sCD40L) in MI patients, but not in healthy controls. The independent association between large PMPs and thrombin generation supports the concept that formation of PMPs is important for increased coagulation activation in MI patients. [ABSTRACT FROM AUTHOR]

A 28-year-old man diagnosed with triple positive antiphospholipid syndrome (APS) and undergoing warfarin experienced three separate admissions to the cardiac ward within a one-month period due to escalating chest pain. While the initial two admissions revealed normal results in cardiological investigations, such as blood tests, electrocardiogram, and echocardiography, the third admission unveiled signs of ST-elevation myocardial infarction (STEMI), despite the patient maintaining an INR (International Normalized Ratio) of 4. Subsequent percutaneous coronary intervention (PCI) exposed spontaneous coronary artery dissection (SCAD) of type 3. Faced with hemodynamic instability and worsening symptoms, the patient underwent stenting and was prescribed dual antiplatelet therapy in addition to warfarin. A follow-up evaluation one month later indicated a normalization of his condition. [ABSTRACT FROM AUTHOR]

(1) Background: The current diagnostic algorithm for acute pulmonary embolism (PE) is associated with the overuse of CT pulmonary angiography (CTPA). An additional highly specific blood test could potentially lower the proportion of patients with suspected PE that require CTPA. The aim was to summarize the literature on the diagnostic performance of biomarkers of patients admitted to an emergency department with suspected acute PE. (2) Methods: Medline and Embase databases were searched from 1995 to the present. The study selection process, data extraction, and risk of bias assessment were conducted by two reviewers. Eligibility criteria accepted all blood biomarkers except D-dimer, and CTPA was used as the reference standard. Qualitative data synthesis was performed. (3) Results: Of the 8448 identified records, only 6 were included. Eight blood biomarkers were identified, of which, three were investigated in two separate studies. Red distribution width and mean platelet volume were reported to have a specificity of ≥ 90% in one study, although these findings were not confirmed by other studies. The majority of the studies contained a high risk of selection bias. (4) Conclusions: The modest findings and the uncertain validity of the included studies suggest that none of the biomarkers identified in this systematic review have the potential to improve the current diagnostic algorithm for acute PE by reducing the overuse of CTPA. [ABSTRACT FROM AUTHOR]

Summary: B‐cell depletion induced by anti‐cluster of differentiation 20 (CD20) monoclonal antibody (mAb) therapy of patients with lymphoma is expected to impair humoral responses to severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) vaccination, but effects on CD8 T‐cell responses are unknown. Here, we investigated humoral and CD8 T‐cell responses following two vaccinations in patients with lymphoma undergoing anti‐CD20‐mAb therapy as single agent or in combination with chemotherapy or other anti‐neoplastic agents during the last 9 months prior to inclusion, and in healthy age‐matched blood donors. Antibody measurements showed that seven of 110 patients had antibodies to the receptor‐binding domain of the SARS‐CoV‐2 Spike protein 3–6 weeks after the second dose of vaccination. Peripheral blood CD8 T‐cell responses against prevalent human leucocyte antigen (HLA) class I SARS‐CoV‐2 epitopes were determined by peptide‐HLA multimer analysis. Strong CD8 T‐cell responses were observed in samples from 20/29 patients (69%) and 12/16 (75%) controls, with similar median response magnitudes in the groups and some of the strongest responses observed in patients. We conclude that despite the absence of humoral immune responses in fully SARS‐CoV‐2‐vaccinated, anti‐CD20‐treated patients with lymphoma, their CD8 T‐cell responses reach similar frequencies and magnitudes as for controls. Patients with lymphoma on B‐cell depleting therapies are thus likely to benefit from current coronavirus disease 2019 (COVID‐19) vaccines, and development of vaccines aimed at eliciting T‐cell responses to non‐Spike epitopes might provide improved protection. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Tissue factor (TF)-induced thrombin generation (TG) ex vivo has been suggested to be an important method to assess thrombotic risk. No studies have investigated the impact of postprandial lipemia on TF-induced TG. Since myocardial infarction (MI) is associated with elevated postprandial levels of triglycerides, we hypothesized a differential impact of postprandial lipemia on coagulation activation in MI-patients and healthy controls. Material and Methods: Elderly survivors of acute MI (n=44) and healthy age-and sex matched controls (n=43) underwent a fat tolerance test (1 gram per kg body weight) to assess coagulation activation during postprandial lipemia. Results: The incremental area under the curve (AUCi) for serum triglycerides was higher in MI-patients than in healthy age-and sex matched controls (5.64±0.52mmol/L⁎h and 3.94±0.39mmol/L⁎h, p=0.012) during the postprandial phase. Subsequent endogenous activation of coagulation, assessed by FVIIa and thrombin generation (F1+2), was similar among groups and not related to levels of triglycerides during the postprandial phase. Healthy individuals had a gradual decline in TF-induced thrombin generation ex vivo, assessed by endogenous thrombin potential (ETP) (AUCi=-542.4±71.4nM⁎min⁎h, p<0.001), whereas MI-patients retained their ETP (AUCi=127.4±89.0nM⁎min⁎h, p=0.47) in plasma during the postprandial phase (p for group difference=0.005). Conclusions: MI-patients had elevated postprandial lipemia and retained their ability for TF-induced TG in plasma ex vivo in the postprandial phase, whereas the capacity gradually decreased in healthy individuals. Further studies are warranted to reveal underlying mechanism(s) and clinical implications. [ABSTRACT FROM AUTHOR]

Abstract: Background: Platelet microparticles (PMPs) possess proatherogenic and procoagulant properties which may play a role in atherogenesis and subsequent thromboembolic complications. The present study was conducted to investigate the possible relationship between carotid atherosclerosis and plasma concentrations of PMPs, and elucidate if plasma levels of PMPs were affected by postprandial hypertriglyceridemia. Methods and results: Subjects with ultrasound-assessed carotid atherosclerotic plaques (echogenic; n=20 and echolucent; n=20), assessed by ultrasonography, and subjects without carotid plaques (n=20) were recruited from a population-based study and underwent a standard fat tolerance test. Subjects with carotid plaques had significantly higher levels of large PMPs than subjects without carotid atherosclerotic plaques (96.7±50.4 µg/l versus 56.1±34.9 µg/l), after adjustments for traditional cardiovascular risk factors and use cardiovascular drugs (p=0.021). Plasma PMPs were not associated with plaque echogenicity. Postprandial hypertriglyceridemia induced a similar increase in plasma PMPs within all groups. Significant correlations were found between an increase in plasma triglycerides and percent elevation in total PMPs (r=0.29, p<0.05) and large PMPs (r=0.34, p<0.01) in the postprandial phase. Conclusions: Individuals with echogenic and echolucent carotid atherosclerotic plaques have statistically significant elevation of large plasma PMPs compared to age/sex-matched normal controls. Postprandial hypertriglyceridemia induces a significant, similar increase in plasma PMPs in individuals with and without carotid atherosclerotic plaques which could be of pathophysiological importance in atherogenesis. [Copyright &y& Elsevier]

Patients with immune thrombocytopenia (ITP) are at increased risk of thrombosis, which seems to be further enhanced by treatment with thrombopoietin-receptor-agonists (TPO-RAs). The underlying mechanisms of thrombosis in ITP are not fully understood. Endothelial cell activation and neutrophil extracellular traps (NETs) play important roles in thrombosis, however, their roles in ITP itself, or in TPO-RA-treatment, have not yet been fully explored. We aimed to investigate whether endothelial cell activation and NETs are involved in the hypercoagulable state of ITP, and whether TPO-RA-treatment enhances endothelial cell activation and NET formation. We measured markers of endothelial cell activation including intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1) and thrombomodulin in 21 ITP patients, and E-selectin in 18 ITP patients. Markers of NET formation, citrullinated histone H3-DNA (H3Cit-DNA) and cell-free DNA (cfDNA), were measured in 15 ITP patients. All markers were measured before, and 2 and 6 weeks after initiation of TPO-RA-treatment in ITP patients, and in matched controls. Higher levels of ICAM-1, thrombomodulin, and H3Cit-DNA were found in ITP patients, both before and after TPO-RA-treatment, compared with controls. No differences were found for VCAM-1, E-selectin or cfDNA. TPO-RA-treatment did not further increase markers of endothelial cell activation or NET formation. This study showed that ITP patients have increased endothelial cell activation and NET formation, both of which may contribute to the intrinsic hypercoagulable state of ITP. TPO-RA-treatment, however, did not further increase endothelial cell activation or NET formation indicating that other drug-associated prothrombotic mechanisms are involved. • ITP patients have higher ICAM-1 and thrombomodulin than controls suggesting increased endothelial cell activation/injury. • ITP patients have higher NET marker H3Cit-DNA than controls indicating increased NET formation in these patients. • Treatment with TPO-RAs does not enhance endothelial cell activation or NET formation. [ABSTRACT FROM AUTHOR]

Objective: The relationship between thyroid function and the risk of venous thromboembolism(VTE) has not been addressed in population-based cohorts. We investigated the association between TSHlevels and the risk of VTE in a general adult population. Design: Population-based cohort study. Methods: TSHwasmeasured in 11 962 subjects aged 25-89 years who participated in Tromsø 4-6 starting in 1994-1995. Incident VTE eventswere recorded through 31st December 2010. Cox's regression models with TSH as a time-varying covariatewere used to calculate hazard ratios (HRs) of VTE by TSH categories (low TSH: <0.05 mU/l; moderately reduced TSH: 0.05-0.19 mU/l; normal TSH: 0.20-4.00 mU/l;moderately elevated TSH: 4.01-5.00 mU/l; and high TSH: >5.00 mU/l) and within the normal range of TSH, modeling TSH as a continuous variable. Results: Therewere 289 VTEs during 8.2 years of median follow-up. Subjectswith low(prevalence: 0.22%) and high (3.01%) TSH had slightly higher risk estimates for VTE than did subjects with normal TSH (multivariable HRs: 2.16, 95%CI 0.69-6.76 and 1.55, 95% CI 0.87-2.77 respectively), but the CIs were wide. Moreover, there was no association between TSH within the normal range and VTE (HR per 1 mU/l increase: 0.95, 95% CI 0.82-1.11). Conclusion: Serum levels of TSH within the normal range were not associated with a risk of VTE, whereas low and high TSH levels were rare and associatedwith amoderately higher risk of VTE. The present findings suggest that only aminor proportion of the VTE risk in the population can be attributed to thyroid dysfunction. [ABSTRACT FROM AUTHOR]

Background--Recent findings suggest that chronic kidney disease (CKD) may be associated with an increased risk of venous thromboembolism (VTE). Given the high prevalence of mild-to-moderate CKD in the general population, in depth analysis of this association is warranted. Methods and Results--We pooled individual participant data from 5 community-based cohorts from Europe (second Nord-TrØndelag Health Study [HUNT2], Prevention of Renal and Vascular End-stage Disease [PREVEND], and the TromsØ study) and the United States (Atherosclerosis Risks in Communities [ARIC] and Cardiovascular Health Study [CHS]) to assess the association of estimated glomerular filtration rate (eGFR), albuminuria, and CKD with objectively verified VTE. To estimate adjusted hazard ratios for VTE, categorical and continuous spline models were fit by using Cox regression with shared-frailty or random-effect meta-analysis. A total of 1178 VTE events occurred over 599 453 person-years follow-up. Relative to eGFR 100 mL/min per 1.73 m², hazard ratios for VTE were 1.29 (95% confidence interval, 1.04-1.59) for eGFR 75, 1.31 (1.00-1.71) for eGFR 60, 1.82 (1.27-2.60) for eGFR 45, and 1.95 (1.26-3.01) for eGFR 30 mL/min per 1.73 m2. In comparison with an albumin-to-creatinine ratio (ACR) of 5.0 mg/g, the hazard ratios for VTE were 1.34 (1.04-1.72) for ACR 30 mg/g, 1.60 (1.08-2.36) for ACR 300 mg/g, and 1.92 (1.19-3.09) for ACR 1000 mg/g. There was no interaction between clinical categories of eGFR and ACR (P=0.20). The adjusted hazard ratio for CKD, defined as eGFR <60 mL/min per 1.73 m² or albuminuria ≥30 mg/g, (versus no CKD) was 1.54 (95% confidence interval, 1.15-2.06). Associations were consistent in subgroups according to age, sex, and comorbidities, and for unprovoked versus provoked VTE, as well. Conclusions--Both eGFR and ACR are independently associated with increased risk of VTE in the general population, even across the normal eGFR and ACR ranges. [ABSTRACT FROM AUTHOR]