Frits R Rosendaal

..Frits Rosendaal comments on new findings from a meta-analysis conducted by Kazem Rahimi and colleagues, evaluating whether statins can prevent venous thromboembolism...

..Our experience with the intricacies of dealing with two control groups may be useful to others when thinking about an optimal research design or the best statistical approach...

..For example, chance circumstances might lead to the incomparability of groups. Bayes' theorem clarifies why different experts may come to opposite conclusions based on the same studies. The ultimate truth remains elusive...

..There are many weak genetic risk factors, including fibrinogen, factor XIII and factor XI variants. Even for moderately strong risk factors (relative risks 2-5), the majority of carriers will never develop thrombosis...

..1 (under an additive model). We conclude that the thrombotic risk of HRT may particularly affect women with prothrombotic mutations. Efforts to avoid HRT in women with increased risk of thrombosis are advisable...

..First results are emerging that specific subgroups of women, with prothrombotic or other abnormalities, may be at risk, especially during the first years of use of hormone substitution...

..The risk of arterial disease in oral contraceptive users and users of hormone replacement therapy is at most weakly affected by the presence of prothrombotic abnormalities...

..In addition to a review of the literature, new data are presented from the MEGA-study. Thrombosis in the elderly should be a focus of future studies...

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..The risk becomes very high in women with a previous venous thrombosis. Randomized trials have not confirmed a beneficial effect of postmenopausal hormones on the occurrence of myocardial infarction...

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..There is no clear synergistic effect of the CC/GG genotype with factor V Leiden or oral contraceptive use on thrombotic risk...

..The aim of this study was to investigate whether common variations in IL1B, IL1RN, IL1R1, and IL1R2 influence the risk of venous thrombosis...

..We recently reported the association between the Malmö sequence variant in F9 (rs6048) and deep vein thrombosis...

..Finding the optimal intensity at which the overall incidence rate of both bleeding and thromboembolic events is minimized represents a way to improve the safety of oral anticoagulant treatment...

..It is unclear whether variations in IL1RN affect the risk of myocardial infarction...

..41, 95% CI: 0.19-0.86). Our findings indicate that polymorphisms in the factorV and PAI-1 genes may play a role in the process of restenosis...

..The aim of the present study was to evaluate the effect of the MTHFR genotype on the risk of venous thrombosis, overall and in subgroups of known risk factors, in a single large study...

..70-13.15); for prothrombin 20210A this was a 6.6-fold increased risk (OR(adj) 6.58, 95% CI 2.31-18.69). Body height, weight and obesity increase the risk of venous thrombosis, especially obesity in women using oral contraceptives...

..Because higher thromboembolic risk with age often makes it unfeasible to withhold oral anticoagulation from elderly patients, future studies should focus on ways to lower the bleeding risk...

..After the introduction of prophylactic treatment, the number of patients who are occupationally disabled is reduced...

..The effect of behavioural factors during flying on the risk of venous thrombosis after air travel is limited. Current advice on prevention of travel-related thrombosis may have to be reconsidered...

..In conclusion, alcohol consumption is associated with a reduced risk of venous thrombosis, which may be in part mediated by decreased fibrinogen levels...

..TAFI regulates fibrinolysis, but other roles of this inhibitor, including anti-inflammatory properties, have also been demonstrated...

..Our findings show that 24 h variation of cardiac risk is not more pronounced among the 4G4G genotype of PAI-1...

..Family history may help in risk stratification, especially in the young. This study assesses the predictive value of a positive family history of cardiovascular disease for myocardial infarction (MI) and ischemic stroke (IS)...

..82 (95% CI, 0.81-0.83), indicating good diagnostic accuracy. To become clinically useful, subgroups of high-risk persons must be identified in whom genetic profiling will also be cost-effective...

..The aim of the study was to evaluate whether varying levels of estradiol and progesterone during the menstrual cycle are associated with differences in sensitivity to APC...

..Our findings suggest that not only clotting factor levels at the extreme of the distribution, resembling mild hemophilia, but also mildly reduced clotting factor levels between 0.41 and 0.60 IU/mL are associated with bleeding...

..However, FVIII gene variations do contribute to both levels of FVIII and the risk of thrombosis...

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..Objective: In the MEGA study, we evaluated pregnancy and the postpartum period as risk factors for venous thrombosis in 285 patients and 857 control subjects...

..These findings suggest that pulmonary embolism and DVT may not always have the same etiology, and encourage unraveling this phenomenon in further studies...

..All had a reduced nA-ratio compared to A(1)O carriers with one repeat in their A(1) allele. The amount of A- and B-antigens expressed onVWF (nA-ratio and nB-ratio) explained about 18% (R(2)) of the variation in VWF levels...

..Surveillance culturing of CVC lock fluid may be clinically useful in estimating the risk for thrombosis and the instigation of focused early intervention...

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..Our aim was to investigate if late stent malapposition in DES could be predicted by immediate postintervention intra-vascular ultrasonography (IVUS)...

..To assess survival and to construct a baseline mortality risk score in primary prevention implantable cardioverter defibrillator (ICD) patients with non-ischaemic or ischaemic heart disease...

..48; 95% CI -0.85 to -2.11). In this study we observed that the levonorgestrel-intrauterine system decreases the resistance to APC which indicates that the levonorgestrel-intrauterine system does not have a prothrombotic effect...

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..So far few studies have investigated possible mechanisms for this so-called FVL paradox...

..Furthermore, we studied the risk of myocardial infarction associated with the simultaneous presence of a coagulation defect (ie, the 20210 AG genotype of prothrombin or the factor V Leiden mutation) and Major cardiovascular risk factors...

..However, details on long-term mortality in these patients are lacking. The aim of this study was to determine long-term mortality in a large cohort of patients with venous thrombosis...

..In 30% of cases the subtherapeutic INR was preceded by an event necessitating vitamin K or discontinuation of the anticoagulant drug...

..We studied the association of venous thrombosis with common minor injuries, such as minor sural muscle ruptures and ankle sprains...

..8% per year. CONCLUSIONS: Extra care after a first event is required for men with a deficiency in natural anticoagulants or multiple defects and women with antithrombin deficiency...

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..These findings support the recommendation for patients on vitamin K antagonists to eat a sufficient amount of vitamin-K containing foods...

..Carriers of the factor V Leiden and prothrombin 20210A mutations appear to have an even higher risk...

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..1-3.5) and the incidence of major thromboembolism from 2.0 (95% CI, 1.5-2.5) to 0.8 (95% CI, 0.5-1.3) per 100 patient-years. CONCLUSION: Implementation of lower target intensities for coumarin therapy decreased the complication risk...

..7; 95% CI, 5.4-498). We conclude that increased levels of FII and FVIII increase the risk of venous thrombosis in travelers. Furthermore, the risk is greatly increased if other risk factors are present as well...

..We conclude that the risk of myocardial infarction for men in the presence of the R2 allele of the His1299Arg polymorphism is neither increased nor decreased...

..However, mainly high VWF and FVIII levels caused by increased secretion seem to be associated with thrombosis. ABO blood group influences the clearance rates of VWF rather than VWF secretion rates...

..5-2.2). Thus, a high ETP was not associated with an increased relative risk of recurrent venous thrombosis. At present, the clinical relevance of the thrombin generation assay in predicting recurrent venous thrombosis remains uncertain...

..CONCLUSION: A CVC is a very strong risk factor for arm thrombosis. Most risk factors for thrombosis in the leg are also risk factors for arm thrombosis...

..4, CI 0.9-21.3), respectively. While not conclusive, these results strongly suggest that the Ala25Thr substitution is a risk factor for myocardial infarction, especially in young men, and when in the presence of additional risk factors...

..8), protein S (ref. 9), antithrombin10 deficiency) together...

..CONCLUSIONS: The incidence of venous events in asymptomatic individuals from thrombophilic families does not exceed the risk of bleeding associated with long-term anticoagulant treatment in the literature (1-3%)...

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..9; 95% CI 0.9-25.6) as well. CONCLUSIONS: The risk of venous thrombosis after travel is moderately increased for all modes of travel. Subgroups exist in which the risk is highly increased...

..This study applied the Common-Sense Model (CSM) to predict risk perception and disease-related worry in 174 individuals with a genetic predisposition to venous thrombosis (thrombophilia)...

..CONCLUSIONS: The results from this population sample show that an altered inflammatory profile is more likely to be a result rather than a cause of VT, although short-term effects of transiently elevated levels cannot be ruled out...

..0-fold increased risk. In conclusion, smoking appears to be a risk factor for venous thrombosis with the greatest relative effect among young women using oral contraceptives...

..We studied the contribution of family history to the risk of venous thrombosis in relation to known risk factors...

..In conclusion, genetic variation in the TAFI gene is associated with risk of SVT, suggesting a role for TAFI in the pathogenetic mechanism of SVT...

..1, 95% CI, 1.3-3.6). The other factors were not associated with an increased risk. Elevated levels of several procoagulant factors are associated with a strongly increased risk of venous thrombosis of the upper extremity...

..These findings do not support the hypothesis that fluid loss contributes to thrombus formation during air travel...

..In conclusion, clinically diagnosed SVT was a risk factor for venous thrombosis. Given that thrombophilia was only weakly associated with SVT, it is likely that other factors (varicosis, obesity, stasis) also play a role in its etiology...

..Our data do not support the hypothesis that a single functional sequence variation in the factor VIII or VWF gene explains the majority of high factor VIII levels and thrombotic risk...

..The risk of myocardial infarction was similar among women who used oral contraceptives whether or not they had a prothrombotic mutation...

..The aim of this study was to examine whether genetic predisposition to high levels of coagulation factors influences the risk of developing fatal and non-fatal arterial cardiovascular events in men with a first myocardial infarction (MI)...

..Genetic variants can alter fibrinogen characteristics and are not subject to these problems...

..This indicates that the relationship between TAFI and venous thrombosis is more complex than previously suggested...

..Selectin polymorphisms/haplotypes have been associated with cardiovascular disease...

..To investigate the factors associated with clinical progression and good prognosis in patients with lower limb osteoarthritis (OA)...

..The genetic causes of deep vein thrombosis (DVT) are not fully understood...

..SHBG levels were positively associated with the increased APC resistance. CONCLUSIONS: Our findings support the hypothesis that the effect of an oral contraceptive on SHBG levels might be a marker for the thrombotic risk...

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..However, this is unlikely to counterbalance the adverse effect of third generation contraceptives on venous thrombosis...

..Risk factor assessment prior to implantation may be useful for identifying patients at risk for thrombotic complications. Preventive management in these patients is warranted...

..We have investigated overall mortality and death from cardiovascular causes in carriers of haemophilia, who in most cases have mildly decreased coagulability without clinical signs...

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..Anti-EPCR autoantibodies have been associated with fetal death and myocardial infarction in young women...

..This study aims to determine the risks of arterial thrombosis conferred by increased activation of intrinsic coagulation proteins in young women and the effect of oral contraceptive use on this association...

..This may manifest itself as a reduced time to pregnancy (increased fecundity) and fewer miscarriages in the first trimester...

..The results of this study indicate that the risk for the joint effects of oral contraceptive use and coagulation factor levels are minor compared with the joint effect of oral contraceptive use and the FV Leiden mutation (RR > 30)...

..For patients with distant metastases, for several types of cancer, prophylactic anti-thrombotic treatment could be beneficial...

..Prophylaxis with anticoagulants is recommended for chest, but not for arm ports. Determination of plasma homocysteine levels may identify patients at an increased risk for thrombosis...

..CONCLUSIONS: In middle aged patients with familial osteoarthritis at multiple sites, familial aggregation of osteoarthritis was most striking for hand and hip but remarkably absent for the knee...

..Lipids, through effects on the coagulation and fibrinolytic systems, may contribute to the development of venous thrombosis. This association has been investigated in a few studies, with conflicting results...

..01 level. Given the impact of venous thrombosis and the postthrombotic syndrome on quality of life, assessment of QOL should be included in future studies on the outcome of venous thrombosis...

..2 (ORadj, 3.2; 95% CI, 2.0-5.1). Thus, factors XIc and XIIc have opposite and synergistic effects on the risk of myocardial infarction in men; factor VIIIc and factor IXc increase the risk...

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