Journal of thrombosis and haemostasis : JTH
-
J. Thromb. Haemost. · Aug 2016
Factor VIII chromogenic assays can be used for potency labeling and postadministration monitoring of N8-GP.
Essentials Chromogenic assays may be less variable than one-stage clot assays for measuring modified factor VIII. Chromogenic assays were evaluated for N8-GP potency labeling and postadministration monitoring. There was no significant difference between chromogenic assay kits for measuring N8-GP potency. Postadministration monitoring of N8-GP was comparable to turoctocog alfa for all kits tested. ⋯ C for N8-GP potency and showed comparable results for N8-GP and turoctocog alfa in simulated postadministration samples.
-
J. Thromb. Haemost. · Jul 2016
ReviewTailoring hemostatic therapies to lower inhibitor development in previously untreated patients with severe hemophilia A.
After technological progress provided safer therapeutic products for patients with hemophilia A, the development of alloantibodies (inhibitors) neutralizing the coagulant activity of infused factor VIII (FVIII) remains the most serious complication of replacement therapy, predisposing patients to greater morbidity and causing higher treatment costs. The pathogenesis of inhibitors, which develop at a high rate in previously untreated children with severe hemophilia A, is multifactorial, resulting from complex interactions between genetic and environmental factors. ⋯ We review the potential interventions on these modifiable factors that may help to lower the rate of inhibitor development. In addition, interest is currently directed toward the potential for lesser immunogenicity of novel hemostatic agents designed to decrease the dosing frequency or avoid/delay the need of FVIII replacement therapy.
-
J. Thromb. Haemost. · Jul 2016
Risk of recurrent venous thromboembolism after discontinuation of vitamin K antagonist treatment: a nested case-control study.
Essentials Vitamin K antagonists (VKA) in venous thromboembolism (VTE) lower the risk of recurrences. 41 841 VKA-treated VTE patients had 1242 recurrent VTEs on therapy or early after cessation. An increased risk of recurrence was found in the first 120 days after VKA cessation. Patient education for the early detection of recurrent VTE after VKA cessation is recommended. ⋯ Background The standard treatment for venous thromboembolism (VTE) and the prevention of recurrent VTE (rVTE) consists of anticoagulant therapy. The optimal duration of anticoagulation depends on the presence of risk factors for rVTE. Objectives To estimate the risk of rVTE in association with time since discontinuation of vitamin K antagonist (VKA) treatment. Methods From the UK Clinical Practice Research Datalink with linked information on hospitalization and cause of death, a cohort of patients with a first VTE receiving initial VKA treatment between 2001 and 2013 was formed. With a nested case-control approach, patients with incident rVTE (cases) were matched to patients with VTE but without rVTE (controls). Adjusted rate ratios (RRs) of rVTE associated with time since VKA discontinuation relative to current VKA use were estimated from conditional logistic regression. Results The VTE cohort comprised 41 841 patients with 1242 rVTEs and 6205 matched controls. The RR of rVTE was increased within 60 days following VKA discontinuation (RR 2.23, 95% confidence interval [CI] 1.71-2.91) and within 61-120 days following VKA discontinuation (RR 1.49, 95% CI 1.08-2.05) relative to current VKA use. The increased RR corresponded to excess incidence rates of 6.72 (95% CI 3.90-10.06) rVTE cases per 100 person-years within 60 days, and of 2.68 (95% CI 0.42-5.58) rVTE cases per 100 person-years within 61-120 days after VKA discontinuation. Conclusions VKA discontinuation results in a transient increased risk of rVTE, which peaks within 60 days and lasts for up to 120 days after VKA discontinuation. Specific patient education for increased vigilance for signs and symptoms of recurrences is recommended in this period.
-
J. Thromb. Haemost. · Jun 2016
Multicenter Study Observational StudyContemporary antiplatelet treatment in acute coronary syndrome patients undergoing percutaneous coronary intervention: 1-year outcomes from the GReek AntiPlatElet (GRAPE) Registry.
Essentials The comparative efficacy and safety of antiplatelet agents in 'real life' is not clear. We recruited acute coronary syndrome patients receiving percutaneous coronary intervention. At 1-year follow-up, prasugrel offers better anti-ischemic protection than clopidogrel. Prasugrel and ticagrelor are accompanied by more frequent bleeding events. ⋯ Background The comparative efficacy and safety of antiplatelet treatment outside randomized trials is not clear. Objectives To investigate long-term efficacy and safety in 'real-life' acute coronary syndrome (ACS) patients treated by percutaneous coronary intervention (PCI) with contemporary use of clopidogrel, prasugrel and ticagrelor. Methods In a prospective, observational, multicenter cohort study, 2047 patients were recruited into the GReek AntiPlatElet (GRAPE) Registry and were followed-up for 1 year for major adverse cardiovascular events (MACE, a composite of death, non-fatal myocardial infarction, urgent revascularization and stroke) and bleeding events (Bleeding Academic Research Consortium [BARC] classification). Results Exposure to clopidogrel, prasugrel and ticagrelor by PCI occurred in 959, 363 and 717 patients, respectively. After adjustment, the rate of MACE (primary outcome endpoint) was lower in prasugrel-treated patients (4.4%) than in clopidogrel-treated patients (10.1%) (hazard ratio [HR], 0.53; 95% confidence interval [CI], 0.30-0.91), although not significantly different between ticagrelor (6.8%) and clopidogrel groups (HR, 0.78; 95% CI, 0.54-1.12). Any type of BARC-classified bleeding (secondary outcome endpoint) was more frequent in prasugrel-treated patients (51.2%) than in clopidogrel-treated patients (37.6%) (HR, 1.61; 95% CI, 1.33-1.95) and more frequent in ticagrelor-treated patients (56.9%) than in clopidogrel-treated patients (HR, 1.81; 95% CI, 1.55-2.10). An adjusted comparison between prasugrel and ticagrelor-treated groups did not reveal differences in any outcome measure. After adjustment, the death rate was more reduced by novel agents in comparison with clopidogrel (2.9% vs. 6.2%). Conclusions In ACS/PCI patients, prasugrel offered better anti-ischemic protection than clopidogrel, whereas use of both novel agents is accompanied by more frequent bleeding events.
-
J. Thromb. Haemost. · Jun 2016
Impact of incident myocardial infarction on the risk of venous thromboembolism: the Tromsø Study.
Essentials Registry-based studies indicate a link between arterial- and venous thromboembolism (VTE). We studied this association in a cohort with confounder information and validated outcomes. Myocardial infarction (MI) was associated with a 4.8-fold increased short-term risk of VTE. MI was associated with a transient increased risk of VTE, and pulmonary embolism in particular. ⋯ Background Recent studies have demonstrated an association between venous thromboembolism (VTE) and arterial thrombotic diseases. Objectives To study the association between incident myocardial infarction (MI) and VTE in a prospective population-based cohort. Methods Study participants (n = 29 506) were recruited from three surveys of the Tromsø Study (conducted in 1994-1995, 2001-2002, and 2007-2008) and followed up to 2010. All incident MI and VTE events during follow-up were recorded. Cox regression models with age as the time scale and MI as a time-dependent variable were used to calculate hazard ratios (HRs) of VTE adjusted for sex, body mass index, blood pressure, diabetes mellitus, HDL cholesterol, smoking, physical activity, and education level. Results During a median follow-up of 15.7 years, 1853 participants experienced an MI and 699 experienced a VTE. MI was associated with a 51% increased risk of VTE (HR 1.51; 95% confidence interval [CI] 1.08-2.10) and a 72% increased risk of pulmonary embolism (PE) (HR 1.72; 95% CI 1.07-2.75), but not significantly associated with the risk of deep vein thrombosis (DVT) (HR 1.36; 95% CI 0.86-2.15). The highest risk estimates for PE were observed during the first 6 months after the MI (HR 8.49; 95% CI 4.00-18.77). MI explained 6.2% of the PEs in the population (population attributable risk) and 78.5% of the PE risk in MI patients (attributable risk). Conclusions Our findings indicate that MI is associated with a transient increased VTE risk, independently of traditional atherosclerotic risk factors. The risk estimates were particularly high for PE.