The influence of thrombophilia on the long-term survival of patients with a history of venous thromboembolism

Genome-wide association study of thoracic aortic aneurysm and dissection in the Million Veteran Program

The current understanding of the genetic determinants of thoracic aortic aneurysms and dissections (TAAD) has largely been informed through studies of rare, Mendelian forms of disease. Here, we conducted a genome-wide association study (GWAS) of TAAD, testing ~25 million DNA sequence variants in 8,626 participants with and 453,043 participants without TAAD in the Million Veteran Program, with replication in an independent sample of 4,459 individuals with and 512,463 without TAAD from six cohorts. We identified 21 TAAD risk loci, 17 of which have not been previously reported. We leverage multiple downstream analytic methods to identify causal TAAD risk genes and cell types and provide human genetic evidence that TAAD is a non-atherosclerotic aortic disorder distinct from other forms of vascular disease. Our results demonstrate that the genetic architecture of TAAD mirrors that of other complex traits and that it is not solely inherited through protein-altering variants of large effect size.

Thrombophilia and outcomes of venous thromboembolism in older patients

Background

Limited data exist on thrombophilic risk factors and clinical outcomes in the elderly with venous thromboembolism (VTE).

Objectives

To describe the prevalence of laboratory thrombophilic risk factors and their association with VTE recurrence or death in a cohort of elderly people with VTE.

Methods

In 240 patients aged ≥65 years with acute VTE without active cancer or an indication for extended anticoagulation, we performed laboratory thrombophilia testing 1 year after the index VTE. Recurrence or death was assessed during the 2-year follow-up.

Results

A total of 78% of patients had ≥1 laboratory thrombophilic risk factor(s). Elevated levels of von Willebrand factor, homocysteine, coagulant activity of factor VIII (FVIII:C), fibrinogen, FIX:C, and low antithrombin activity were the most prevalent risk factors (43%, 30%, 15%, 14%, 13%, and 11%, respectively). Additionally, 16.2% of patients experienced VTE recurrence and 5.8% of patients died. Patients with a von Willebrand factor of >182%, FVIII:C level >200%, homocysteine level >15μmol/L, or lupus anticoagulant had a significantly higher rate of recurrence than those without these risk factors (15.0 vs. 6.1 [P = .006], 23.5 vs. 8.2 [P = .01], 17.0 vs. 6.8 [P = .006], and 89.5 vs. 9.2 [P = .02] events per 100 patient-years, respectively). Furthermore, patients with a high fibrinogen level or hyperhomocysteinemia with a homocysteine level ≥30 μmol/L had significantly higher mortality than patients with normal levels (18.5 vs. 2.8 [P = .049] and 13.6 vs. 2 [P = .002] deaths per 100 patient-years, respectively). After adjustments for relevant confounders, these associations remained unchanged.

Conclusion

Laboratory thrombophilic risk factors are common in elderly people with VTE and allow for the identification of a population at the risk of worse clinical outcomes.

Thrombophilia Impact on Treatment Decisions, Subsequent Venous or Arterial Thrombosis and Pregnancy-Related Morbidity: A Retrospective Single-Center Cohort Study

(1) Background: Thrombophilia testing utility has remained controversial since its clinical introduction, because data on its influence on treatment decisions are limited. (2) Methods: We conducted a single-center retrospective cohort study of 3550 unselected patients referred for thrombophilia consultation at the Bern University Hospital in Switzerland from January 2010 to October 2020. We studied the influence of thrombophilia testing results on treatment decisions and evaluated the association between thrombophilia and thromboembolic and pregnancy-related morbidity events after testing up to 03/2021. (3) Results: In 1192/3550 patients (34%), at least one case of thrombophilia was found and 366 (10%) had high-risk thrombophilia. A total of 211/3550 (6%) work-ups (111/826 (13%) with low-risk thrombophilia and 100/366 (27%) with high-risk thrombophilia) led to an appropriate decision to extend or initiate anticoagulation, and 189 (5%) negative results led to the withholding of anticoagulation therapy inappropriately. A total of 2492 patients (69%) were followed up for >30 days, with a median follow-up of 49 months (range, 1−183 months). Patients with high-risk thrombophilia had a higher risk of subsequent venous thromboembolic events and pregnancy-related morbidity compared to those without thrombophilia. (4) Conclusions: Our study demonstrated the limited usefulness of thrombophilia work-up in clinical decision-making. High-risk thrombophilia was associated with subsequent venous thromboembolism and pregnancy-related morbidity.

Role of Inherited Thrombophilia Risk Factors in Patients with CKD-5 Receiving Haemodialysis

BACKGROUND

The inherited thrombophilic mutations of the factor V gene (FVG1691A Leiden-FVL), prothrombin gene (PTG20210A), and the methylenetetrahydrofolate reductase gene C677T (MTHFR C677T) are risk factors for thromboembolic events and are related to the pathogenesis of vascular diseases.

OBJECTIVES

The main objective of this study was to explore the role of these factors in the pathogenesis of chronic kidney disease (CKD) and survival of patients with CKD-5 receiving haemodialysis.

METHODS

A cohort of 395 patients with CKD-5 on haemodialysis, from 6 dialysis units in Crete, Greece were recruited based on their medical records and were followed for 5 years. We collected data on CKD-5 aetiology, thrombophilic gene expression, vascular access thrombosis, time of death, and causes of death.

RESULTS

The mutated genes just as prevalent in patients with CKD-5 as they were in a control group with no renal disease (p > 0.05). FVL heterozygosity was significantly more prevalent (11.4 vs. 5.7%; p = 0.036) in patients presented with CKD of unknown aetiology, compared to CKD secondary to known aetiologies. The survival of patients with CKD-5 receiving haemodialysis was not affected by the presence of any thrombophilic mutation. This held true for the whole cohort and for the cohort that included only lethal vascular events. Most patients with MTHFR C677T heterozygosity, and all patients with MTHFR C677T homozygosity, died from vascular events during the follow-up period.

CONCLUSION

The FVL mutation may act as a risk factor for CKD. This study increases our understanding of molecular mechanisms in the pathogenesis of CKD of unknown aetiology. Τhe presence of thrombophilic mutations did not affect the overall survival of patients with CKD-5. This finding probably reflects the effect of medical care on patient outcomes.

Chronic complications of venous thromboembolism

Venous thromboembolism (VTE) is a common disease (~700 per 100 000) that is associated with significant risk of recurrence, chronic complications, and substantial mortality, with reported death rates of up to 40% at 10 years. The development of novel anticoagulants has revolutionized the treatment of acute VTE, while strategies for prevention and treatment of chronic complications still seek for such a landmark change. Impaired thrombus resolution is the common denominator behind VTE complications, which are postthrombotic syndrome (PTS) and chronic thromboembolic pulmonary hypertension (CTEPH). PTS and CTEPH are associated with substantial morbidity and high healthcare expenses. While PTS occurs in up to 50% of patients after symptomatic deep vein thrombosis, only a small and poorly defined number of patients are diagnosed with CTEPH after pulmonary embolism. This review is a comprehensive summary of VTE-related chronic complications, their epidemiology, diagnosis, and treatment.

ANMCO Position Paper: long-term follow-up of patients with pulmonary thromboembolism

Venous thromboembolism (VTE), including pulmonary embolism and deep venous thrombosis, is the third most common cause of cardiovascular death. The management of the acute phase of VTE has already been described in several guidelines. However, the management of the follow-up (FU) of these patients has been poorly defined. This consensus document, created by the Italian cardiologists, wants to clarify this issue using the currently available evidence in VTE. Clinical and instrumental data acquired during the acute phase of the disease are the cornerstone for planning the FU. Acquired or congenital thrombophilic disorders could be identified in apparently unprovoked VTE during the FU. In other cases, an occult cancer could be discovered after a VTE. The main targets of the post-acute management are to prevent recurrence of VTE and to identify the patients who can develop a chronic thromboembolic pulmonary hypertension. Knowledge of pathophysiology and therapeutic approaches is fundamental to decide the most appropriate long-term treatment. Moreover, prognostic stratification during the FU should be constantly updated on the basis of the new evidence acquired. Currently, the cornerstone of VTE treatment is represented by both the oral and the parenteral anticoagulation. Novel oral anticoagulants should be an interesting alternative in the long-term treatment.

Guidance for the evaluation and treatment of hereditary and acquired thrombophilia

Thrombophilias are hereditary and/or acquired conditions that predispose patients to thrombosis. Testing for thrombophilia is commonly performed in patients with venous thrombosis and their relatives; however such testing usually does not provide information that impacts management and may result in harm. This manuscript, initiated by the Anticoagulation Forum, provides clinical guidance for thrombophilia testing in five clinical situations: following 1) provoked venous thromboembolism, 2) unprovoked venous thromboembolism; 3) in relatives of patients with thrombosis, 4) in female relatives of patients with thrombosis considering estrogen use; and 5) in female relatives of patients with thrombosis who are considering pregnancy. Additionally, guidance is provided regarding the timing of thrombophilia testing. The role of thrombophilia testing in arterial thrombosis and for evaluation of recurrent pregnancy loss is not addressed. Statements are based on existing guidelines and consensus expert opinion where guidelines are lacking. We recommend that thrombophilia testing not be performed in most situations. When performed, it should be used in a highly selective manner, and only in circumstances where the information obtained will influence a decision important to the patient, and outweigh the potential risks of testing. Testing should not be performed during acute thrombosis or during the initial (3-month) period of anticoagulation.

Elevated levels of factor VIII and subsequent risk of all-cause mortality: results from the MEGA follow-up study

BACKGROUND

Factor VIII (FVIII) levels are increased in individuals with a non-O blood group and play a role in the etiology of thrombosis. High FVIII levels have also been associated with increased all-cause mortality.

OBJECTIVE

We explored whether elevated FVIII levels are associated with an increased risk of death in patients who had venous thrombosis and in individuals from the general population, and to what extent this association is causal.

METHODS

We followed 2178 patients with previous venous thrombosis and 2827 age and sex-matched community controls for on average 5.5 years and measured their FVIII levels and ABO blood group.

RESULTS

All-cause mortality increased in a dose-response fashion with increasing percentiles of FVIII levels. In the thrombosis patients the risk was highest above the 97.5th percentile (FVIII > 199 IU dL(-1) ) with an adjusted hazard ratio (HR) of 3.1 (95% confidence interval [CI], 0.9-10.8) as compared with patients in the 25th percentile category (FVIII ≤ 85 IU dL(-1) ). The adjusted HR was 4.5 (95% CI, 1.4-14.3) in controls. Using non-O blood group as a measure of genetically elevated FVIII levels to determine a causal relationship between FVIII and death showed observed HRs of 0.99 (95% CI, 0.72-1.36) in patients and 1.25 (95% CI, 0.82-1.90) in controls.

CONCLUSIONS

We showed a dose-response relationship between high FVIII levels and risk of death in venous thrombosis patients and in individuals from the general population. However, environmental factors, such as chronic comorbidities and chronic inflammation, are at least in part responsible for the association between factor VIII and mortality.

Global hypercoagulability in patients with schizophrenia receiving long-term antipsychotic therapy

BACKGROUND

Patients with schizophrenia are at increased risk of venous thromboembolism. The mechanisms underlying this association are poorly understood.

AIMS

We investigated whether there is a global hypercoagulable state in patients with schizophrenia utilising the overall haemostatic potential (OHP) assay which assesses overall coagulation potential (OCP), haemostatic potential (OHP) and fibrinolytic potential (OFP).

METHOD

Citrated plasma was collected for OHP assays from patients with schizophrenia on long-term antipsychotic treatment and compared with healthy age- and sex-matched controls. Time courses of fibrin formation and degradation were measured by spectrophotometry (absorption of 405nm) after the addition of tissue factor and tissue plasminogen activator to plasma.

RESULTS

Ninety patients with schizophrenia (antipsychotic treatment-15.9±9.7years) and 30 controls were recruited. Patients with schizophrenia had higher rates of smoking and levels of inflammatory markers (high-sensitivity C-reactive protein and neutrophil-to-lymphocyte ratio) than controls. Whilst D-dimer, fibrinogen and platelet count did not differ between patients with schizophrenia and controls, the OCP (54.0±12.6 vs 45.9±9.1, p=0.002) and OHP (12.6±5.8 vs 7.2±3.7, p<0.001) were higher, and OFP was lower (76.6±9.8% vs 84.9±6.4%, p<0.001) in patients with schizophrenia, implying both a hypercoagulable and hypofibrinolytic state in these patients. Importantly, abnormalities in overall coagulation were independently predicted by levels of plasminogen-activator-inhibitor-1, fibrinogen, platelet count, inflammatory markers and plasma triglycerides, suggesting a multifactorial aetiology.

CONCLUSION

Patients with schizophrenia have evidence of a global hypercoagulable and hypofibrinolytic state which may contribute to their increased risk of venous thromboembolism.

Recurrent venous thromboembolism in a patient with heterozygous factor v leiden mutation

OBJECTIVE

To report a patient case identifying risk for recurrent venous thromboembolism (VTE) associated with heterozygous Factor V Leiden mutation.

CASE SUMMARY

A 54-year-old Caucasian male was diagnosed with heterozygous Factor V Leiden mutation in 2008 after experiencing a deep vein thrombosis (DVT) and bilateral pulmonary embolism. The patient was treated appropriately and started on anticoagulation therapy with warfarin through an anticoagulation management clinic. After approximately 17 months of warfarin therapy without incident, warfarin was discontinued. Within 2 months after discontinuation of anticoagulation therapy, the patient experienced his second DVT and left pulmonary artery embolus.

DISCUSSION

The risk of recurrent venous thromboembolism (VTE) in patients with heterozygous Factor V Leiden mutation is documented as an approximate 1.4-fold increase compared to patients without thrombophilia. However, the risk increases dramatically when nonreversible (age) or reversible risk factors (obesity, smoking, and long air flights) are present in this population.

CONCLUSION

Based on recent literature, heterozygous Factor V Leiden mutation exponentially increases the risk of recurrent VTE, especially in the presence of other risk factors. Health care providers should complete a comprehensive review of the patients' other risk factors when deciding on duration of anticoagulation therapy for patients with positive heterozygous Factor V Leiden mutation.