Role of factor V Leiden or G20210A prothrombin mutation in patients with symptomatic pulmonary embolism and deep vein thrombosis: a meta-analysis of the literature

Thrombosis risk in single- and double-heterozygous carriers of factor V Leiden and prothrombin G20210A in FinnGen and the UK Biobank

ABSTRACT

The factor V Leiden (FVL; rs6025) and prothrombin G20210A (PTGM; rs1799963) polymorphisms are 2 of the most well-studied genetic risk factors for venous thromboembolism (VTE). However, double heterozygosity (DH) for FVL and PTGM remains poorly understood, with previous studies showing marked disagreement regarding thrombosis risk conferred by the DH genotype. Using multidimensional data from the UK Biobank (UKB) and FinnGen biorepositories, we evaluated the clinical impact of DH carrier status across 937 939 individuals. We found that 662 participants (0.07%) were DH carriers. After adjustment for age, sex, and ancestry, DH individuals experienced a markedly elevated risk of VTE compared with wild-type individuals (odds ratio [OR] = 5.24; 95% confidence interval [CI], 4.01-6.84; P = 4.8 × 10-34), which approximated the risk conferred by FVL homozygosity. A secondary analysis restricted to UKB participants (N = 445 144) found that effect size estimates for the DH genotype remained largely unchanged (OR = 4.53; 95% CI, 3.42-5.90; P < 1 × 10-16) after adjustment for commonly cited VTE risk factors, such as body mass index, blood type, and markers of inflammation. In contrast, the DH genotype was not associated with a significantly higher risk of any arterial thrombosis phenotype, including stroke, myocardial infarction, and peripheral artery disease. In summary, we leveraged population-scale genomic data sets to conduct, to our knowledge, the largest study to date on the DH genotype and were able to establish far more precise effect size estimates than previously possible. Our findings indicate that the DH genotype may occur as frequently as FVL homozygosity and may confer a similarly increased risk of VTE.

Donor-derived disorders of hemostasis and thrombosis in liver transplantation: Considerations for deceased donor liver selection

OLT is known to be associated with a precarious perioperative hemostatic state due to dysregulation of procoagulant and anticoagulant factors, endothelial injury, and inflammation. Transmission of inherited bleeding and clotting disorders from the liver donor to the recipient may further complicate hemostasis during and after transplantation. As a result, consideration of congenital coagulation disorders in the liver donor is a practical concern for donor selection. However, there is no clear consensus regarding the selection of donors with known or suspected thrombophilia or bleeding disorders. While multiple case reports and retrospective studies, subject to reporting bias, describe donor-derived thrombophilic and bleeding disorders, there are no large-scale studies in the adult liver transplant literature that examine the frequency of transmission, utility of donor screening, or clinical impact of donor hemostatic disorders. Based on the reported literature, we summarize our approach for donor selection with an aim to balance improved organ utility and optimal post-transplant outcomes.

Factor V Leiden G1691A and Prothrombin Gene G20210A Mutations on Pregnancy Outcome

Factor V Leiden (FVL) G1619A mutation and prothrombin gene (PTG) G20210A are the most common inherited thrombophilias. They have been associated with various obstetric complications such as venous thromboembolism, recurrent pregnancy loss, preeclampsia, abruptio placentae, and small for gestational age fetus. The prevalence of these two mutations is 3-15% in Caucasians and is assumed to be far less common in other ethnic populations. However, there have been several controversies regarding advising routine screening of these thrombophilias because of a widely variable strength of association between different ethnic groups, as well as contradictory conclusions by different studies in regards to the association. In this study, the literature was analyzed thoroughly for the effect of FVL G1619A and PTG G20210A mutations on various obstetric outcomes. A review of multiple case-control and prospective studies suggests that despite the availability of robust data on this subject the results remain inconclusive and insubstantial. Further superior quality research, preferably prospective studies, is warranted to conclusively establish this relationship and to enable practitioners to follow a definitive protocol in the screening of various populations for these mutations to achieve an improved pregnancy outcome.

Sickle Cell Disease: A Paradigm for Venous Thrombosis Pathophysiology

Venous thromboembolism (VTE) is an important cause of vascular morbidity and mortality. Many risk factors have been identified for venous thrombosis that lead to alterations in blood flow, activate the vascular endothelium, and increase the propensity for blood coagulation. However, the precise molecular and cellular mechanisms that cause blood clots in the venous vasculature have not been fully elucidated. Patients with sickle cell disease (SCD) demonstrate all the risk factors for venous stasis, activated endothelium, and blood hypercoagulability, making them particularly vulnerable to VTE. In this review, we will discuss how mouse models have elucidated the complex vascular pathobiology of SCD. We review the dysregulated pathways of inflammation and coagulation in SCD and how the resultant hypercoagulable state can potentiate thrombosis through down-regulation of vascular anticoagulants. Studies of VTE pathogenesis using SCD mouse models may provide insight into the intersection between the cellular and molecular processes involving inflammation and coagulation and help to identify novel mechanistic pathways.

By word of mouse: using animal models in venous thrombosis research

Deep vein thrombosis (DVT) is a disease with high prevalence and morbidity. It can lead to pulmonary embolism with severe respiratory insufficiency and risk of death. Mechanisms behind all stages of DVT, such as thrombosis commencement, propagation, and resolution, remain incompletely understood. Animal models represent an invaluable tool to explore these problems and identify new targets for DVT prevention and treatment. In this review, we discuss existing models of venous thrombosis, their advantages and disadvantages, and applicability to studying different aspects of DVT pathophysiology. We also speculate about requirements for an "ideal model" that would best recapitulate features of human DVT and discuss readouts of various models.

Gas embolism during endoscopic retrograde cholangiopancreatography: diagnosis and management

Air embolism is rarely diagnosed and is often fatal. The diagnosis is often not made in a timely manner given the rapid and severe clinical deterioration that often develops, frequently leading to cardiac arrest. Many patients are only diagnosed post-mortem. With the increasing use of endoscopic retrograde cholangiopancreatography, air embolism should be considered in the differential diagnosis in patients who experience sudden clinical deterioration during or immediately after the procedure. Clinical suspicion is key in the diagnosis and management of air embolism. Use of precordial Doppler ultrasound and transesophageal echocardiogram can aid in the diagnosis of air embolism. Once the diagnosis is made, supportive management of airway, breathing and circulation is pivotal. Advanced cardiac life support should be initiated when necessary. Fluid resuscitation and vasopressors can improve cardiac output. Hyperbaric oxygen therapy should be considered when possible in cases of suspected cerebral air embolism cases to improve neurological outcome. A multidisciplinary team approach and effective communication with experts, potentially including an anesthesiologist, cardiologist, intensivist, radiologist and surgeon, can improve the outcome in air embolism.

Primary and secondary haemostasis changes related to aging

Life expectancy has increased in many countries as a result the world's population is aging. The projections indicate that the proportion of the elderly in a few decades will increase significantly. Aging carries with it a series of physiological changes; one of them is an imbalance in the hemostatic system. Thus the levels or activity of various proteins involved, such as most coagulation factors, natural anticoagulants and the fibrinolytic system are altered so that the hemostatic balance leans toward thrombosis. Also, platelet activity suggests a state of abnormal activation (P-selectin, beta thromboglobulin and platelet factor). In this review we will systematically examine the alterations in the hemostatic components that occur during aging. Therefore, understanding these hemostatic changes could contribute to developing strategies for the proper management of health in old age.

Associations of coagulation factor V Leiden and prothrombin G20210A mutations with Budd-Chiari syndrome and portal vein thrombosis: a systematic review and meta-analysis

BACKGROUND & AIMS

We conducted a systematic review and meta-analysis to evaluate the associations of the coagulation factor V (encoded by F5) Leiden (FVL) or prothrombin (encoded by F2) G20210A mutation with Budd-Chiari syndrome or portal vein thrombosis (PVT).

METHODS

Relevant articles were identified in searches of the PubMed, EMBASE, Cochrane Library, and ScienceDirect databases. The prevalence of the FVL and prothrombin G20210A mutations were compared between patients with Budd-Chiari syndrome or PVT without cirrhosis and healthy individuals (controls) and between patients with cirrhosis, with and without PVT. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated.

RESULTS

We initially identified 869 articles, and included 27 in our final analysis. Compared with controls, patients with Budd-Chiari syndrome had a significantly higher prevalence of the FVL mutation (OR, 6.21; 95% CI, 3.93-9.79) and a similar prevalence of the prothrombin G20210A mutation (OR, 1.90; 95% CI, 0.69-5.23); patients with PVT without cirrhosis had a significantly higher prevalence of the FVL mutation (OR, 1.85; 95% CI, 1.09-3.13) or the prothrombin G20210A mutation (OR, 5.01; 95% CI, 3.03-8.30). Compared with patients with cirrhosis without PVT, patients with cirrhosis and PVT had a significantly higher prevalence of the FVL mutation (OR, 2.55; 95% CI, 1.29-5.07). We observed a trend toward a higher prevalence of the prothrombin G20210A mutation in patients with cirrhosis and PVT, but the difference was not statistically significant (OR, 2.93; 95% CI, 0.94-9.07).

CONCLUSIONS

Based on a meta-analysis, the FVL mutation is associated with an increased risk of Budd-Chiari syndrome, PVT without cirrhosis, and PVT in cirrhosis. The prothrombin G20210A mutation is associated with PVT, but not Budd-Chiari syndrome. Studies are needed to confirm these findings in different racial and ethnic groups.

Family History of Myocardial Infarction and Cause-Specific Risk of Myocardial Infarction and Venous Thromboembolism

Background—

A family history of myocardial infarction (FHMI) has been shown to increase the risk of venous thromboembolism (VTE). The mechanism underlying the association remains unclear. Therefore, we aimed to determine the risks of MI and VTE by FHMI using a cause-specific model and to explore whether atherosclerotic risk factors could explain the association between FHMI and VTE in a population-based cohort.

Methods and Results—

The study included 21 624 subjects recruited from the Tromsø Study in 1994 to 1995 and 2001 to 2002. Incident MI and VTE events were registered from date of enrollment to end of follow-up, December 31, 2010. There were 1311 MIs and 428 VTEs during a median follow-up of 15.8 years. FHMI was associated with a 52% increased risk of MI (adjusted hazard ratio, 1.52; 95% confidence interval, 1.35–1.70) and a 26% increased risk of VTE (adjusted hazard ratio, 1.26; 95% confidence interval, 1.02–1.55) in the cause-specific Cox model. Similar results were found using the traditional Cox model. The risk estimates by status of FHMI were highest for unprovoked deep vein thrombosis (adjusted hazard ratio, 1.69; 95% confidence interval, 1.12–2.56), and the risk increased with increasing number of affected relatives. Modifiable atherosclerotic risk factors slightly altered the association between FHMI and MI but had a negligible effect on the association between FHMI and VTE.

Conclusions—

FHMI was associated with increased risk of both MI and VTE in a cause-specific model. Apparently, the association between FHMI and VTE applied to unprovoked deep vein thrombosis and was not explained by modifiable atherosclerotic risk factors.

The association of factor V Leiden with various clinical patterns of venous thromboembolism-the factor V Leiden paradox

BACKGROUND

Factor V Leiden (FVL) supposedly carries relatively higher risk of deep vein thrombosis (DVT), compared to the risk of pulmonary embolism (PE).

AIM

To prove this paradox in a group of patients with various clinical presentation of venous thromboembolism (VTE).

MATERIALS AND METHODS

We retrospectively evaluated clinical pattern of VTE in patients who had been referred to vascular clinic shortly after an acute VTE event. In FVL positive and FVL negative groups we compared the prevalence of isolated symptomatic DVT (proximal or distal) and symptomatic PE with/without DVT, and, moreover, asymptomatic DVT or PE.

RESULTS

Of 575 patients (mean age 57 years, 50.1% women), 120 were FVL positive and those had significantly higher prevalence of isolated symptomatic DVT, compared to symptomatic PE with/without DVT. Proximal DVT location was significantly more frequent in FVL carriers. The prevalence of asymptomatic PE did not differ between the two groups. The rate of asymptomatic DVT tended to be higher in FVL negative group. In a multivariate analysis, we confirmed FVL to be positively associated with isolated DVT presentation (odds ratio OR 1.757; 95% confidence interval (CI) 1.148-2.690). On the contrary, increasing age and unprovoked nature of VTE event carried a higher risk of symptomatic PE.

CONCLUSIONS

We confirmed FVL to be significantly associated with isolated symptomatic DVT despite higher prevalence of proximal DVT in FVL carriers. The fact of relatively lower risk of PE in FVL positive patients might have clinical implication. However, mechanisms of FVL paradox remain to be elucidated.

Association between thrombophilia and the post-thrombotic syndrome: a systematic review and meta-analysis

BACKGROUND

The postthrombotic syndrome (PTS) is a frequent chronic complication of deep vein thrombosis (DVT), occurring in 20-40% of patients. Identifying risk factors for PTS may be useful to provide patients with prognostic information and target prevention strategies.

OBJECTIVE

To conduct a systematic review to assess whether, among patients with DVT, inherited and acquired thrombophilias are associated with a risk of PTS.

METHODS

We searched the electronic databases PubMed, EMBASE, Scopus, and Web of Science for studies published from 1990 to 2013 that assessed any thrombophilia in adult DVT patients and its association with the development of PTS. We calculated odds ratios and 95% confidence intervals for PTS according to the presence of thrombophilia. Meta-analysis was performed using the random-effects model.

RESULTS

Sixteen studies were included: 13 assessed factor V Leiden (FVL), 10 assessed prothrombin mutation, five assessed protein S and C deficiencies, three assessed antithrombin deficiency, four assessed elevated FVIII levels, and six assessed antiphospholipid antibodies. None of the meta-analyses identified any thrombophilia to be predictive of PTS. Both FVL and prothrombin mutation appeared protective among studies including patients with both first and recurrent DVT and studies in which more than 50% of patients had an unprovoked DVT.

CONCLUSIONS

Our meta-analysis did not demonstrate a significant association between any of the thrombophilias assessed and the risk of PTS in DVT patients. Other biomarkers in the pathophysiological pathway may be more predictive of PTS.

Meta-analysis of Factor V Leiden G1691A polymorphism and osteonecrosis of femoral head susceptibility

Testing for genetic risk associations between Factor V Leiden (FVL) and the osteonecrosis of femoral head (ONFH) is common, however, inconsistent results have been previously obtained. To summarize results on the association of FVL mutation polymorphism with ONFH in various populations and to calculate the overall genetic risk factors, we performed a search of electronic databases including PubMed, Elsevier Science Direct, Chinese National Knowledge Infrastructure and the Chinese Biomedical Database to identify published studies correlating the FVL mutation with ONFH. Statistical analysis was performed using Review Manager (RevMan) version 5.0 and Stata statistical software (version 10). We identified 57 titles and included 7 studies comprising 481 cases and 867 controls in this meta-analysis. The groups were pooled, and a significant association between FVL mutation and increased ONFH was found (OR=4.55, 95% CI, 2.75-7.52, P<0.00001). This meta-analysis demonstrated that FVL plays an important role in non-Asian populations. Large sample studies including different ethnic groups and age- and gender-matched groups, as well as multiple gene polymorphism detection should be considered to clarify the association of FVL mutation polymorphism and ONFH susceptibility in the future.