Dose escalation of low molecular weight heparin in patients with recurrent cancer-associated thrombosis

Introduction

Patients with cancer-associated thrombosis are at a high risk of developing recurrent events despite anticoagulant therapy. Escalation of the dose of low molecular weight heparin (LMWH) has been suggested as a potential treatment option to manage these patients. We sought to confirm the benefit and risk of this management strategy in patients with recurrent cancer-associated thrombosis.

Material and Methods

A retrospective cohort study of consecutive cancer outpatients seen for management of a symptomatic recurrent cancer-associated thrombosis while on anticoagulation was undertaken. Objectively confirmed episodes of recurrent thrombosis were treated with either dose escalation of LMWH or initiation of therapeutic dose of LMWH in patients already anticoagulated with LMWH or vitamin K antagonist (VKA) respectively. Included patients were followed for a minimum of 3 months after the index recurrent event.

Results

Fifty-five cancer patients with a recurrent venous thromboembolism (VTE) despite anticoagulation were included. At the time of the recurrence, 89% of patients were on LMWH. The median time between the initial cancer-associated thrombosis to the index recurrent event was 2.3 months (range 0.1 to 30.4 months). Four patients (7.3%; 95% CI: 2.0 to 17.6%) had a second recurrent VTE during the 3-month follow-up period. Three patients (5.5%; 95% CI 1.1 to 15.1%) had major bleeding complications after dose escalation of LMWH. There were no recurrent fatal VTE or major bleeding episodes.

Conclusion

Escalating the dose of LMWH seems effective and safe for managing patients with recurrent cancer-associated thrombosis despite anticoagulant therapy.     

Mutations in NSCLC and their link with lung cancer-associated thrombosis: A case-control study

Introduction

The association of venous thromboembolic events (VTE) and lung cancer is highly prevalent. Additionally, the occurrence of a VTE with cancer has been associated with a worse prognosis and a poor quality of life. Underlying cancer biological features such as tumour mutations may contribute to VTE risk and cancer prognosis. Since preclinical data suggest a link between thrombosis and KRAS mutations in tumours, we aimed to validate this association in a patient registry cohort. Methods: A retrospective case control study was performed using the CHUM NSCLC registry. Cases had VTE occurring 6 months previous to or after a diagnosis of NSCLC. Diagnosis of VTE (venous thrombosis, pulmonary embolism, and migratory superficial thrombophlebitis) was confirmed by a review of the imaging reports. Controls were patients with NSCLC without thrombosis matched for age and stage (I-IIIA/IIIB-IV). Exclusion criteria included insufficient tissue for KRAS/EGFR mutation analysis or insufficient clinical information.

Results

Between Jan 2000 and Dec 2009 a total of 57 cases with VTE and 102 controls without VTE were included. The OR for thrombosis in KRAS and EGFR mutated NSCLC patients are respectively 2.67 (1.12-6.42; p = 0.014) and 0.99 (0.27-3.48; p = 0.99).

Conclusions

KRAS mutation is associated with an increased risk of VTE in this NSCLC cohort. These findings are consistent with preclinical studies. Prospective data on VTE rates from clinical trials with molecularly defined NSCLC are needed to confirm these findings.     

Tumour expresion of tissue factor and tissue factor pathway inhibitor in ovarian cancer- relationship with venous thrombosis risk

Introduction

Ovarian cancer is known to display a particular association with venous thromboembolism (VTE) with reports up to 42% of patients developing thromboembolic complications. Tissue Factor (TF) and its inhibitor Tissue Factor Pathway Inhibitor (TFPI) have been implicated in VTE risk in cancer. The aim of this study was to measure tumour derived TF and TFPI and to investigate their potential role in VTE in ovarian cancer patients.

Methods

TF and TFPI mRNA expression was measured using TaqMan real time PCR in 99 ovarian tumour samples. Nineteen cases complicated by VTE were matched to 19 cases without VTE. TF and TFPI protein levels were measured using ELISA and immunohistochemistry was used to localize TF expression. The role of TF expression on overall survival was also determined.

Results

TF mRNA and protein expression was increased in tumours from patients with clear cell carcinoma (p < 0.001). TF protein expression was also increased in endometroid carcinoma (P < 0.01) compared with benign tumours. TFPI mRNA expression was increased in clear cell carcinoma (P < 0.01). TF mRNA and antigen level was increased in malignant tumours of patients who developed VTE compared with matched malignant õtumours of patients who remained thrombosis free (P < 0.01). There was no difference in TFPI expression between the two groups.

Conclusion

TF expression in ovarian cancer is significantly higher in patients who develop VTE. TF expression was increased in clear cell ovarian cancer and endometroid cancer and this may explain the higher risk of VTE in these subgroups. TF derived from these tumours may be the trigger for VTE in ovarian cancer.     

Two years outcome of isolated distal deep vein thrombosis

Background

Isolated distal deep vein thrombosis (IDDVT) is frequently found in symptomatic outpatients, but its long term outcome is still uncertain.

Aims

To assess IDDVT long term outcome and the impact of IDDVT characteristics on outcome.

Methods

In a prospective, single center study we enrolled symptomatic outpatients in whom IDDVT was detected by whole-leg compression ultrasonography. Patients with provoked IDDVT were treated with low molecular weight heparins (LMWH) for 30 days while those with unprovoked IDDVT received with vitamin K antagonists (VKA) for three months. The primary end-point was the rate of the composite of pulmonary embolism (PE), proximal deep vein thrombosis (DVT), and IDDVT recurrence/extension during 24 month follow-up.

Results

90 patients (age 61 ± 18, male 48.9%) were enrolled. Risk factors for thrombosis were reduced mobility (34.4%), obesity (25.3%), surgery (15.6%), and previous DVT (15.6%) and cancer in 8 patients (8.9%). Eighty-eight patients were treated (56 with LMWH and 32 with VKA). During follow-up (median 24 ± 2 months), 17 events were recorded, which included 3 PE (two in cancer patients), 4 proximal DVTs (one in cancer patient) and 10 IDDVT. Male sex (HR 4.73 CI95%: 1.55-14.5; p = 0.006) and cancer (HR 5.47 CI95%: 1.76-17.6; p = 0.003) were associated with a higher risk of complications, whereas IDDVT anatomical characteristics, anticoagulant therapy type, and provoked IDDVT were not.

Conclusions

The risk of recurrent venous thromboembolism after IDDVT may be relevant in male patients or in patients with active cancer. Larger studies are needed to address this issue.     

Atorvastatin favorably modulates proinflammatory cytokine profile in patients following deep vein thrombosis

Background

Venous thromboembolism (VTE) has been shown to be associated with inflammation. Statins that might reduce VTE risk have been found to exert anti-inflammatory properties in patients at cardiovascular risk. We sought to investigate whether anti-inflammatory effects of atorvastatin can be observed in VTE patients.

Materials and Methods

Atorvastatin 40 mg/d was given for 3 days to 26 consecutive VTE patients following discontinuation of anticoagulant therapy and 25 controls. We evaluated interleukin (IL)-1b, IL-6, IL-8, IL-10, soluble P-selectin and von Willebrand factor (vWF) antigen in peripheral venous blood.

Results

The VTE patients displayed higher C-reactive protein (p = 0.013), IL-1b (p = 0.03), IL-8 (p = 0.03) and vWF (p < 0.0001) compared with the controls. In VTE patients atorvastatin decreased IL-6 (p = 0.0003), IL-8 (p = 0.003) and P-selectin (p < 0.0001), but increased IL-10 (p = 0.001), with no association with C-reactive protein or cholesterol-lowering effects. Atorvastatin reduced IL-1b (p = 0.01), IL-6 (p = 0.03) and P-selectin (p = 0.002) in controls. Residual venous thrombosis was associated with elevated IL-6 and P-selectin, whereas patients with proximal deep vein thrombosis showed elevated P-selecitn prior to and following statin administration (all p < 0.05).

Conclusion

A 3-day administration of atorvastatin reduces inflammation without decrease in C-reactive protein in VTE patients.     

Statins are Associated with Low Risk of Venous Thromboembolism in Patients with Cancer: A Prospective and Observational Cohort Study

Introduction

Patients with cancer are at risk of venous thromboembolism (VTE). Statin-use has been shown to be associated with low risk of VTE in patients without cancer, but data in cancer patients is scarce. The objective of this study was to evaluate the association of statins with risk of VTE in cancer patients in a prospective observational cohort study.

Materials and Methods

Patients with newly diagnosed cancer or progression of disease after remission were included and prospectively followed for a maximum of 2 years. Study endpoint was occurrence of symptomatic VTE.

Results

Patients (n = 1434) were followed over a median observation period of 729 days. VTE occurred in 107 (7.5%) patients. At study inclusion, 170 (11.9%) patients took statins. Simvastatin (n = 96) and atorvastatin (n = 48) were the most frequently prescribed statins. VTE occurred in 6 (3.5%) patients with statins. Patients with statins had a lower risk of VTE than patients without (subhazard ratio 0.43, 95% confidence interval 0.19 to 0.98; p = 0.04). In competing risk analysis, the cumulative probability of VTE in patients with statins was 2.94% after 12 months and 3.54% after 24 months, compared to 7.13% and 8.13% in the group without statins (Gray’s test: p = 0.04).

Conclusion

This study provides observational evidence for an association between statin use and low risk of VTE in patients with cancer. The role of statins for prevention of cancer-associated VTE needs to be confirmed in randomized, controlled trials.     

Apolipoprotein M and the risk of unprovoked recurrent venous thromboembolism

Introduction

Apolipoprotein M (ApoM) protects against atherosclerosis; however, it is unknown whether it also protects against recurrent venous thromboembolism (VTE).

Material and Methods

Patients in the Malmö Thrombophilia Study (MATS) were followed post-anticoagulant treatment until the diagnosis of recurrent VTE or the end of the study (mean follow-up 36 months). Among patients with a first episode of unprovoked VTE, we identified 43 patients (9.7%) with recurrent VTE during the follow-up period. Three age- and sex-matched control subjects without recurrent VTE were selected for each case (n = 129). Plasma levels of ApoM were quantified by a sandwich ELISA method.

Results

Among all patients, the plasma levels (mean ± SD) of ApoM were not significantly different between patients with recurrent (0.70 ± 0.2) and non-recurrent VTE (0.74 ± 0.2), p = 0.2. However, after stratification of data according to gender, male patients with recurrent VTE showed significantly (p = 0.02) lower ApoM levels (0.63 ± 0.2) as compared to those with non-recurrent VTE (0.74 ± 0.2). No significant differences in ApoM levels were found between recurrent (0.8 ± 0.2) and non-recurrent VTE (0.75 ± 0.2) in female patients, p = 0.3. Cox-regression analysis showed that the risk of recurrent VTE was 0.98 (95% CI, 0.96-0.99) for each 0.01 μM increase in ApoM level in male patients (p = 0.042), and this risk remained unchanged after adjusting for inherited thrombophilia and body mass index (p = 0.027). ApoM levels were not associated with the risk of recurrent VTE in female patients.

Conclusion

Our results show that levels of ApoM in recurrent VTE may differ according to gender and lower levels of ApoM may predict VTE recurrence in male patients.     

Clinical predictors of recurrent venous thromboembolism: a single institute experience in Korea

Introduction

Racial disparities in incidence rate as well as risk factors for venous thromboembolism (VTE) exist between Asian and Western populations. Moreover, predictors for recurrent VTE were not identified in Asians. Thus, this study was undertaken to investigate risk factors for recurrent VTE events in Korean people.

Materials and Methods

Three hundred-three patients newly diagnosed as VTE were enrolled from Seoul National University Hospital. Recurrence rate based on risk factors for VTE were investigated. Cumulative incidence of recurrent VTE was calculated by the Kaplan and Meier method. Independent predictors for VTE were determined using Cox proportional hazards model.

Results

After a median follow-up of 44 months, 24 (8%) of 303 patients relapsed for a total observation time of 1,217 patient-year. Cumulative incidences of recurrent VTE were 3% at 1 year, 10% at 5 years, and 18% at 8 years. Independent predictors for recurrent VTE were presence of residual thrombosis (hazard ratio [HR] = 3.1, 95% confidence interval [CI] 1.0-9.3; p = 0.044), antiphospholipid syndrome (APS) (HR = 4.3, 95% CI 1.0-19.0; p = 0.052), and age 50 years or younger (HR = 2.5, 95% CI 1.0-6.6; p = 0.053) by multivariate analysis. Residual thrombosis and APS remained predictive of recurrence by the anticoagulation-period stratified analysis.

Conclusions

In contrast to Western populations, Korean patients with VTE had the lower recurrent rate. Extended anticoagulation is necessary for Korean patients with residual thrombosis or APS.     

Risk factors for recurrent venous thromboembolism in young and middle-aged women

Background

It is a matter of debate whether women with an episode of VTE associated with estrogen have a lower risk of recurrence than women with an unprovoked VTE.

Objectives

To identify risk factors for recurrent VTE in women and to assess the risk of recurrent VTE associated with combined oral contraceptives (CHC) or menopausal hormone treatment (HT), compared to surgery-related and unprovoked VTE.

Patients/Methods

A cohort of 974 women aged 18–64 years with a first episode of VTE were followed-up for a median time of 5.2 years. All women were previously included as cases in the Swedish nation-wide case–control study “Thrombo Embolism Hormone Study” (TEHS). Hazard ratios for recurrence were calculated using univariable and multivariable Cox proportional hazards model.

Results

A total of 102 patients (10%) suffered from recurrent VTE. The annual rate of recurrence was 1.0% in patients with surgery/cast, 2.0% in patients with CHC/HT and 3.2% in patients with unprovoked first VTE. Adjusted hazards ratio (HR_a) for recurrence was 0.35 (95% CI 0.20-0.61) in women with VT provoked by surgery/cast while women with estrogen-associated VTE had a HR_a of 0.70 (95% CI 0.43-1.20) compared to women with unprovoked VTE.

Conclusion

Women 18–64 years are at low risk of recurrent VTE. Women with hormone associated VTE had a lower risk of recurrence than women with unprovoked VTE, but not as low as surgery/cast provoked VTE.     

Incidence and risk factors of symptomatic venous thromboembolism related to implanted ports in cancer patients

Introduction

The true incidence of symptomatic implanted port related venous thromboembolism (VTE) in cancer patients is unclear and there is very limited data on its associated risk factors.

Materials and methods

We performed a retrospective cohort study of consecutive cancer outpatients who received an ultrasound guided implanted port insertion for the administration of chemotherapy. The primary outcome measure was symptomatic VTE. Univariable and multivariable logistic regression analyses were used to identify risk factors for symptomatic VTE.

Results

A total of 400 cancer patients with a newly inserted implanted port for deliverance of chemotherapy were included in the study. Median age was 58 years (range of 21 to 85 years) and 120 (30%) were males. Patients were followed for a median of 12 months and none received thrombophrophylaxis. Of the 400 patients included in the analysis, 34 patients (8.5%; 95% CI: 6.0 to 11.7%) had symptomatic VTE (16 DVTs, 16 PEs, and 2 with both). In the univariate analyses, metastatic disease, male gender and right sided implanted port insertion were significantly associated with the risk of VTE. In the multiple-variable analysis, male gender (OR 2.17, p = 0.04) and presence of metastases (OR 8.22, p < 0.01) were the two significant independent predictors of implanted port related VTE.

Conclusion

Symptomatic VTE is a frequent complication in cancer patients with implanted port receiving chemotherapy. Gender and presence of metastatic disease are independent risk factors for symptomatic VTE. Future trials assessing the role of thromboprophylaxis among these higher risk patients are needed.     

A shortened activated partial thromboplastin time predicts the risk of catheter-associated venous thrombosis in cancer patients

Introduction

Hypercoagulability due to high coagulation factor levels resulting from host inflammatory response to cancer contributes to an increased risk of venous thromboembolism (VTE) in cancer patients. Central venous catheters (CVCs) further heighten this risk. Activated partial thromboplastin time (aPTT) can be used to broadly screen for elevated levels of relevant coagulation factors. Our objective was to determine if a shortened aPTT ratio (coagulation time of test- to- reference plasma) was a predictor of CVC-associated VTE in cancer patients.

Materials and Methods

We performed a retrospective case–control study on cancer patients undergoing tunneled CVC insertion at our center from 1999 to 2006 and identified 40 patients who had CVC-associated VTE. VTE was confirmed with color duplex ultrasonography or computed tomography scan. For each case, we obtained 5 controls that had the same cancer diagnosis and were matched on the following factors: age, chemotherapy, hormone therapy (if applicable), tobacco use, TNM staging and year of diagnosis. All patients had aPTT testing within 30 days prior to surgery. We compared aPTT and aPTT ratio between cases and controls using Wilcoxon two sample test.

Results

aPTT ratio was significantly shorter in patients with CVC-related VTE as compared to controls [0.86 (95% confidence interval (CI) 0.78, 0.94) vs. 0.98 (0.94, 1.01), p = 0.0003]. Mean aPTT was also significantly shorter. [25.6 seconds (95% CI 23.2, 27.9) vs. 28.1 (26.9, 29.3), p = 0.001] aPTT ratios of the controls tended to spread across larger aPTT ratio values whereas those of cases tended to clustered around the mean.

Conclusions

Cancer patients undergoing catheter placement who develop CVC-associated VTE have a shorter aPTT and aPTT ratio than those who do not develop VTE. aPTT, a simple and inexpensive test might be useful as a predictor of CVC-associated VTE risk in cancer patients.     

Evaluation of the prevalence of severe hyperhomocysteinemia in adult patients with thrombosis who underwent screening for thrombophilia

Introduction

Treatment with B-vitamins and betaine reduces the high risk of thrombosis in patients with homocystinuria, a metabolic syndrome that is characterized by severe hyperhomocysteinemia (HHcy). In contrast, there is no clear demonstration that B-vitamins reduce the risk of thrombosis in patients with mild HHcy: for this reason, many question the clinical utility of measuring total Hcy (tHcy) in patients with thrombosis. However, thrombosis may be the first clinical manifestation of homocystinuria in patients reaching adulthood without signs and symptoms of the syndrome.

Aim

1) to measure the prevalence of severe, previously undiagnosed, HHcy among patients with thrombosis 2) to profile these patients on the basis of their characteristics.

Methods

Six Italian Thrombosis Centers completed a first questionnaire, reporting tHcy levels in patients with thrombosis who underwent thrombophilia screening, and a second questionnaire, reporting the characteristics of patients with severe HHcy (tHcy > 100 μmol/L).

Results

Of 19,678 cross-sectionally collected patients with thrombosis who underwent thrombophilia screening in the last 12.5 years (median value, range 6-17), 38 had severe HHcy (0.2%). Their median age at diagnosis was 47 years (range 19-83) and the median level of tHcy was 130 μmol/L (range 101-262). Venous thromboembolism (71%) was more frequent than arterial thromboembolism (26%); recurrent thrombosis occurred in 42% of cases.

Conclusions

Measurement of tHcy in adult patients with thrombosis may reveal the presence of severe HHcy. Since treatment of patients with severe HHcy decreases the risk of thrombosis, measurement of tHcy in patients with thrombosis may prove clinically useful.     

Haplotypes of TAFI gene and the risk of cerebral venous thrombosis - a case-control study

Introduction

Cerebral venous thrombosis (CVT) is an uncommon disease with some differences compared to other-site thrombosis, including a higher frequency in young people, female sex and oral contraceptive users. Thrombin-activatable fibrinolysis inhibitor (TAFI) is a regulator of fibrinolysis, whose levels are genetically controlled and its increase is associated to thrombosis. Our objective was to investigate in a case-control study the association between CVT and TAFI single nucleotide polymorphisms (SNPs) and its haplotypes in comparison to other-site venous thrombosis and controls.

Materials and Methods

Seventy two patients with CVT were compared to 143 individuals with no history of thromboembolic events (control group) and to 128 patients with deep vein thrombosis in the limbs and/or pulmonary embolism (venous thromboembolism-VTE group). SNPs were genotyped by restriction fragment length polymorphism or allele-specific PCR for F2 20210G > A, F5 1691G > A, TAFI (-1053C > T, -438G > A, 505G > A, 1040C > T and + 1542C > G).

Results

The GTC haplotype for TAFI 505G > A/1040C > T/+ 1542C > G SNPs was associated with an increased risk of CVT compared to controls [odds ratio (OR) 2.67, 95% confidence interval (CI): 1.13 - 6.34) and VTE group (OR 2.51, 95%CI: 1.07 - 8.06). The CVT risk became even more pronounced when evaluating unprovoked or hormone-related thrombosis cases: CVT compared to controls (OR 3.24, 95%CI: 1.19 - 8.82) and VTE group (OR 4.32, 95%CI: 1.27 - 14.63).

Conclusions

Our data indicate that the GTC haplotype for TAFI 505G > A/1040C > T/+ 1542C > G SNPs increased the risk of CVT in comparison to controls and VTE cases. Further studies are required to confirm our findings.     

Incidental venous thromboembolism detected by PET-CT in patients with cancer: Prevalence and impact on survival rate

Introduction

People with cancer are at increased risk of incidental venous thromboembolism (VTE) and PET-CT imaging is commonly used in this population. However, the prevalence of incidental VTE detected by PET-CT in patients with cancer and its impact on survival are unknown.

Materials and Methods

This retrospective study was approved by the local Institutional Review Board. 1331 consecutive adult patients with cancer who underwent PET-CT examination between 2009 and 2012 were included in the study (mean age: 57 ± 15 years). PET-CT reports were reviewed to identify patients with incidental VTE at the time of examination. Survival rates were assessed with Kaplan-Meier curves. The Cox proportional hazards model was used to determine the association between incidental VTE and overall survival, after controlling for clinical variables.

Results

Incidental VTE was detected in 19 patients (1.4%). Patients with genitourinary malignancies, colorectal cancer and lung cancer had the highest rates of incidental VTE at PET-CT. At multivariate analysis, incidental VTE detected by PET-CT was associated with worse overall survival independently of patient age, hospitalization status at time of PET-CT examination, and the presence of metastatic disease (Hazard ratio = 2.03; 95% confidence interval = 1.08-3.81, p = 0.028).

Conclusion

Incidental VTE was detected in 1.4% of adult patients with cancer undergoing PET-CT imaging. Diagnosis of incidental VTE at PET-CT imaging was associated with worse overall survival in this population.     

Cost-Effectiveness Analysis of Extended Duration Anticoagulation with Rivaroxaban to Prevent Recurrent Venous Thromboembolism

Introduction

Extended duration anticoagulation with rivaroxaban for an additional 6–12 months can reduce recurrent venous thromboembolic events (VTE) compared to placebo by ~ 82%, but at the detriment of increased bleeding. We sought to estimate the cost-effectiveness of extended duration prophylaxis of recurrent VTE with rivaroxaban.

Material and Methods

A Markov model was developed to estimate the cost-effectiveness of extended duration rivaroxaban, 20 mg daily, compared to placebo using a Medicare perspective, a one-month cycle length and a 40-year time horizon. The model assumed a cohort of 58-year-old patients who had already completed an initial 6–12 months of anticoagulation with rivaroxaban or a vitamin K antagonist; and whom prescribers had clinical equipoise with respect to the need for continued anticoagulation. Data sources included EINSTEIN-Extension and other published studies of VTE. Outcomes included direct treatment costs (in 2013US$), quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs).

Results

Extended duration rivaroxaban resulted in higher treatment costs ($22,645 vs. $22,083) but yielded greater QALYs (16.167 vs. 16.134) as compared to placebo; corresponding to an ICER of $17,030/QALY gained. Our model was most sensitive to the baseline risk of bleeding and recurrent VTE, the hazard ratio of developing a recurrent event while on rivaroxaban and time horizon. Monte Carlo Simulation suggested rivaroxaban would be cost-effective in 66% of 10,000 iterations, assuming a willingness-to-pay threshold of $50,000/QALY.

Conclusion

Despite the cost of rivaroxaban and an increased risk of bleeding, extending VTE treatment for an additional 6–12 months with rivaroxaban was found cost-effective compared to the placebo over a 40-year time horizon.     

Risk factors for arterial thrombosis in antiphospholipid syndrome

Introduction

Antiphospholipid syndrome (APS) is associated with the risk of both arterial and venous thrombosis. However, it is not known which factors might determine the location of thrombosis.

Materials and Methods

To retrospectively characterize factors associated with the risk of arterial thrombosis in a cohort of APS patients. Analysis included laboratory and clinical criteria of APS, together with classical cardiovascular risk factors and the possible role of platelet integrin α₂β₁ (807 C/T) and α_IIbβ₃ (PI A1/2) genetic polymorphisms. We enrolled 163 APS patients (123 women and 40 men aged 21-75; mean age 43 years); 78 suffered from arterial thrombosis.

Results

There were no significant differences in the frequency or titers of different antiphospholipid antibodies with the exception of slightly increased frequency of IgG anticardiolipin antibodies (ACL) in the arterial thrombosis group. Livedo reticularis was observed significantly more often in the arterial thrombosis group, particularly in stroke patients.In univariate analysis arterial thrombosis was associated with male gender (OR-2,201; p = 0,033), arterial hypertension (OR-2,81; p = 0,002) and hypercholesterolemia (OR-3,69; p = 0,001). On multivariate analysis arterial hypertension (OR = 1,78; p = 0,008) and hypercholesterolemia (OR = 2,001; p = 0,002) remained as independent risk factors for arterial thrombosis. Platelet glycoprotein polymorphisms studied did not show any significant associations with arterial thrombosis in APS patients.

Conclusions

Among APS patients those with ACL IgG antibodies, having livedo reticularis, and suffering from hypertension an hypercholesterolemia are at the increased risk of arterial thrombosis.     

Efficacy of postoperative anticoagulation therapy with enoxaparin for portal vein thrombosis after hepatic resection in patients with liver cancer

Backgrounds

Enoxaparin, low-molecular-weight heparin, has become a routine thromboprophylaxis in general surgery.

Study design

A retrospective cohort study was performed in 281 patients who underwent hepatic resections for liver cancers from 2011 to 2013. These patients were divided into two groups; an enoxaparin (-) group (n = 228) and an enoxaparin (+) group (n = 53). Short-term surgical results including venous thromboembolism (VTE) and portal vein thrombosis (PVT) were compared.

Results

In the enoxaparin (+) group, the patients’ age (65 vs. 69 years; p = 0.01) and BMI (22.9 vs. 24.4; p < 0.01) were significantly higher. According to the symptomatic VTE, symptomatic pulmonary embolism occurred in one patient (0.4%) in the enoxaparin (-) group, but the complication rate was not significantly different (p = 0.63). The complication rate of PVT was significantly lower in the enoxaparin (+) group (10 vs. 2%; p = 0.04). The independent risk factors for PVT were an operation time ≥ 300 minutes (Odds ratio 6.66) and non-treatment with enoxaparin (Odds ratio 2.49).

Conclusions

Postoperative anticoagulant therapy with enoxaparin could prevent PVT in patients who underwent hepatic resection for liver cancers.     

Direct oral anticoagulants in the treatment of acute venous thromboembolism: A systematic review and meta-analysis

Introduction

Acute venous thromboembolism (VTE) is a common disease associated to significant morbidity and mortality.

Materials and methods

We systematically reviewed and meta-analysed clinical outcomes with direct oral anticoagulants (DOAC: dabigatran, rivaroxaban, apixaban or edoxaban) for treatment of acute VTE. We used MEDLINE and CENTRAL, clinical trials registers, conference proceedings, and websites of regulatory agencies to identify randomised clinical trials of DOAC compared with conventional treatment [parenteral anticoagulant followed by a vitamin K antagonist (VKA)] for acute VTE. Two investigators independently extracted data. Relative risk of recurrent VTE, bleeding events, deaths and a net clinical endpoint (composite of recurrent VTE, major bleeding, and death) were estimated using a random effect meta-analysis (RevMan software).

Results

Six trials including 27,127 patients were selected. The risk of recurrent VTE was similar with the DOAC and standard treatment (relative risk 0.91, 95% confidence interval 0.79 to 1.06). The DOAC reduced the risk of major bleeding in comparison with standard treatment (0.62, 0.45 to 0.85) (absolute risk difference, − 0.6%; 95% confidence interval − 1.0% to − 0.3%), but there was heterogeneity across trials in the relative risk of bleeding. No between treatment differences were found in the relative risk of all-cause mortality (0.98, 0.84 to 1.14). The DOAC and conventional treatment differed on the net clinical endpoint (0.85, 0.75 to 0.97). Subgroup analyses in relevant subgroups (index pulmonary embolism, heparin lead-in, age, gender, renal function, presence of cancer), as well as sensitivity analyses, were consistent with the main analysis.

Conclusions

The DOAC seem as effective as, and probably safer than standard treatment of acute VTE. The relative efficacy and safety of the DOAC was consistent across a wide range of patients.     

Association between the plasminogen activator inhibitor-1 4G/5G polymorphism and risk of venous thromboembolism: A meta-analysis

Introduction

The plasminogen activator inhibitor-1 (PAI-1) 4G/5G polymorphism was considered to be associated with risk of venous thromboembolism (VTE), while evidence remains inadequate. To provide a more accurate estimation of this relationship, we performed an updated meta-analysis of all eligible studies.

Materials and Methods

A systematical search was performed in PubMed, EMBASE, Wanfang, China National Knowledge Infrastructure (CNKI) and Cqvip databases to identify relevant studies published before March 6^th 2014. The odds ratios (ORs) with 95% confidence intervals (CIs) were pooled using the fixed/random-effects model using Review Manager 5.1 and STATA 12.0.

Results

A total of 34 studies with 3561 cases and 5693 controls were analyzed. Overall, significant association between the PAI-1 4G/5G variant and VTE risk in total population (dominant model: OR = 1.32, 95%CI: 1.13-1.54) was observed. And this variant was also related to the deep vein thrombosis risk (dominant model: OR = 1.60, 95%CI: 1.24-2.06, P = 0.0003). In the subgroup analyses on ethnicity, significant results were obtained in both Asians (dominant model: OR = 2.08, 95%CI: 1.29-3.35, P = 0.003) and Caucasians (dominant model: OR = 1.31, 95%CI: 1.10-1.56, P = 0.003). However, no significant association was found in patients with provoked VTE. In terms of subgroup analyses on co-existence of other thrombotic risk factors, the PAI-1 4G/5G polymorphism was significantly associated with VTE risk in patients with factor V Leiden mutation (dominant model: OR = 1.72, 95%CI: 1.17-2.53), but not in patients with cancer or surgery.

Conclusion

Our findings demonstrate the role of PAI-1 4G/5G polymorphism being a risk candidate locus for VTE susceptibility, especially in patients with other genetic thrombophilic disorders.     

Cost-effectiveness of rivaroxaban versus warfarin anticoagulation for the prevention of recurrent venous thromboembolism: A U.S. perspective

Introduction

Rivaroxaban is an oral direct factor Xa inhibitor that is noninferior to warfarin in the prevention of recurrent venous thromboembolism (VTE). Whether rivaroxaban is cost-effective in the prevention of recurrent VTE, however, is not known.

Material and Methods

To assess the cost effectiveness of rivaroxaban compared with warfarin in the prevention of recurrent VTE, we built a Markov state-transition model over a 10-year time horizon. The base case analysis consisted of a hypothetical cohort of 60-year-old patients with an initial VTE who received secondary prophylaxis with either rivaroxaban or warfarin for 3 to 12 months. Cost estimates were derived from the Healthcare and Utilization Project and other sources. Probabilities were based on literature values. Outcomes included costs in 2011 United States dollars, quality-adjusted life-years (QALYs), and incremental cost effectiveness ratios (ICERs) over 10 years from a societal perspective.

Results

Compared with warfarin, the rivaroxaban strategy cost less ($3,195 vs. $6,188) and was more effective (9.29 QALYs vs 9.14 QALYs). Our results were highly robust in sensitivity analyses. Warfarin was no longer dominated by rivaroxaban when the risk of major bleeding with rivaroxaban exceeds 3.8% (base case estimate: 0.96%).

Conclusion

In summary, prophylactic anticoagulation with rivaroxaban appears to be a cost effective, and perhaps cost saving, alternative to warfarin for the prevention of recurrent VTE.