Predicting recurrences or major bleeding in cancer patients with venous thromboembolism. Findings from the RIETE Registry

Cancer patients with acute venous thromboembolism (VTE) have an increased incidence of recurrences and bleeding complications while on anticoagulant therapy. Methods RIETE is an ongoing registry of consecutive patients with acute VTE. We tried to identify which cancer patients are at a higher risk for recurrent pulmonary embolism (PE), deep vein thrombosis (DVT) or major bleeding. Up to May 2007, 3,805 cancer patients had been enrolled in RIETE. During the first three months of follow-up after the acute, index VTE event, 90 (2.4%) patients developed recurrent PE, 100 (2.6%) recurrent DVT, 156 (4.1%) had major bleeding. Forty patients (44%) died of the recurrent PE,46 (29%) of bleeding. On multivariate analysis, patients aged <65 years (odds ratio [OR]: 3.0; 95% confidence interval [CI]: 1.9-4.9), with PE at entry (OR: 1.9; 95% CI: 1.2-3.1), or with <3 months from cancer diagnosis to VTE (OR: 2.0; 95% CI: 1.2-3.2) had an increased incidence of recurrent PE. Those aged <65 years (OR: 1.6; 95% CI: 1.0-2.4) or with <3 months from cancer diagnosis (OR: 2.4; 95% CI: 1.5-3.6) had an increased incidence of recurrent DVT. Finally, patients with immobility (OR: 1.8; 95% CI: 1.2-2.7), metastases (OR: 1.6; 95% CI: 1.1-2.3), recent bleeding (OR: 2.4; 95% CI: 1.1-5.1), or with creatinine clearance <30 ml/min (OR: 2.2; 95% CI: 1.5-3.4), had an increased incidence of major bleeding. With some variables available at entry we may identify those cancer patients withVTE at a higher risk for recurrences or major bleeding.     

Predictive variables for major bleeding events in patients presenting with documented acute venous thromboembolism. Findings from the RIETE Registry

A score that can accurately determine the risk of major bleeding during anticoagulant therapy may help to make decisions on anticoagulant use. RIETE is an ongoing registry of consecutive patients with acute venous thromboembolism (VTE). We composed a score to predict the risk for major bleeding within three months of anticoagulant therapy. Of 19,274 patients enrolled, 13,057 (67%) were randomly assigned to the derivation sample, 6,572 to the validation sample. In the derivation sample 314 (2.4%) patients bled (fatal bleeding, 105). On multivariate analysis, age >75 years, recent bleeding, cancer, creatinine levels >1.2 mg/dl, anemia, or pulmonary embolism at baseline were independently associated with an increased risk for major bleeding. A score was composed assigning 2 points to recent bleeding, 1.5 to abnormal creatinine levels or anemia, 1 point to the remaining variables. In the derivation sample 2,654 (20%) patients scored 0 points (low risk); 9,645 (74%) 1-4 points (intermediate); 758 (5.8%) >4 points (high risk). The incidences of major bleeding were: 0.3% (95% confidence interval [CI]: 0.1-0.6), 2.6% (95% CI: 2.3-2.9), and 7.3% (95% CI: 5.6-9.3), respectively. The likelihood ratio test was: 0.14 (95% CI: 0.07-0.27) for patients at low risk;2.96 (95% CI: 2.18-4.02) for those at high risk. In the validation sample the incidence of major bleeding was: 0.1%, 2.8%, and 6.2%, respectively. In conclusion, a risk score based on six variables documented at entry can identify VTE patients at low, intermediate, or high risk for major bleeding during the first three months of therapy.     

Short-term clinical outcome after acute symptomatic pulmonary embolism

Though studies have identified clinical variables that predict adverse events in patients with acute pulmonary embolism (PE), they have typically not differentiated short-term from long-term predictors. This multicenter prospective cohort study included consecutive outpatients with objectively confirmed symptomatic acute PE. We analyzed the incidence and time course of death, venous thromboembolism (VTE) recurrence, and major bleeding, and we compared event rates during short-term (first week) and long-term (3 months) follow-up after the diagnosis of PE. We also assessed risk factors for short-term mortality. During the first three months after diagnosis of PE, 142 of 1,338 (10.6%) patients died. Thirty-six deaths (2.7%) occurred during the first week after diagnosis of PE, and 61.1% of these were due to PE. Thirty-eight patients (2.8%) had recurrent VTE during the three-month follow-up, though none of the recurrences occurred during the first week after diagnosis of PE. During the three-month follow-up, major bleeding occurred in 48 patients (3.6%). Twenty-one (1.6%) major bleeds occurred during the first week of follow-up, and nine of these were fatal. Short-term mortality was significantly increased in patients who initially presented with systolic arterial hypotension (odds ratio [OR] 3.35; 95% CI, 1.51-5.41) or immobilization due to a medical illness (OR 2.89; 95% confidence interval [CI], 1.31-6.39). In conclusion, during the first week after the diagnosis of PE, death and major bleeding occur more frequently than recurrent VTE. Patients with systolic arterial hypotension and immobilization at the time of PE diagnosis had an increased risk of short-term mortality.     

Interventional treatment of venous thromboembolism: a review

Venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), is the third most common cardiovascular disease after coronary artery disease and cerebrovascular disease and is responsible for significant morbidity and mortality in the general population. Full dose anticoagulation is the standard therapy for VTE, both for the acute and the long-term phase. The latest guidelines of the American College of Chest Physicians recommend treatment with a full-dose of unfractioned heparin (UFH), low-molecular-weight-heparin (LMWH), fondaparinux, vitamin K antagonist (VKA) or thrombolysis for most patients with objectively confirmed VTE. Catheter-guided thrombolysis and trombosuction are interventional approaches that should be used only in selected populations; interruption of the inferior vena cava (IVC) with a filter can be performed to prevent life-threatening PE in patients with VTE and contraindications to anticoagulant treatment, bleeding complications during antithrombotic treatment, or VTE recurrences despite optimal anticoagulation. In this review we summarize the currently available literature regarding interventional approaches for VTE treatment (vena cava filters, catheter-guided thrombolysis, thrombosuction) and we discuss current evidences on their efficacy and safety. Moreover, the appropriate indications for their use in daily clinical practice are reviewed.     

Elevated white blood cell count and outcome in cancer patients with venous thromboembolism. Findings from the RIETE Registry

A significant association between elevated white blood cell (WBC) count and mortality in patients with cancer has been reported, but the predictive value of elevated WBC on mortality in cancer patients with acute venous thromboembolism (VTE) has not been explored. RIETE is an ongoing registry of consecutive patients with acute VTE. We compared the three-month outcome of cancer patients with acute VTE according to their WBC count at baseline. As of May 2007, 3805 patients with active cancer and acute VTE had been enrolled in RIETE. Of them, 215 (5.7%) had low- (<4,000 cells/microl), 2,403 (63%) normal- (4,000-11,000 cells/microl), 1,187 (31%) elevated (>11,000 cells/microl) WBC count. During the study period 190 patients (5.0%) had recurrent VTE, 156 (4.1%) major bleeding, 889 (23%) died (399 of disseminated cancer, 113 of PE, 46 of bleeding. Patients with elevated WBC count at baseline had an increased incidence of recurrent VTE (odds ratio [OR]: 1.6; 95% confidence interval [CI]: 1.2-2.2), major bleeding (OR: 1.5; 95% CI: 1.1-2.1) or death (OR: 2.7; 95% CI: 2.3-3.2). Most of the reported causes of death were significantly more frequent in patients with elevated WBC count. Multivariate analysis confirmed that elevated WBC count was independently associated with an increased incidence of all three complications. In conclusion, cancer patients with acute VTE and elevated WBC count had an increased incidence of VTE recurrences, major bleeding or death. This worse outcome was consistent among all subgroups and persisted after multivariate adjustment.     

Long-term therapy with low-molecular-weight heparin in cancer patients with venous thromboembolism

Long-term therapy with low-molecular-weight heparin (LMWH) is the treatment of choice for cancer patients with venous thromboembolism (VTE). However, the ideal doses of LMWH have not been thoroughly studied. We used the RIETE Registry data to assess the influence of the daily LMWH dosage on outcome during the first three months after VTE. We used propensity score-matching to compare patients who received <150 vs. those receiving ≥150 UI/kg/day LMWH. Up to July 2010, 3,222 cancer patients with VTE received long-term therapy with fixed doses of LMWH. Of these, 1,472 (46%) received <150 IU/kg/day (mean, 112 ± 28), and 1,750 received ≥150 IU/kg/day (mean, 184 ± 32). Results of the propensity score matching involved 1269 matched pairs. During follow-up, the incidence of pulmonary embolism (PE) recurrences was similar (1.2% vs. 1.9%), but patients receiving <150 IU/kg/day LMWH had a lower incidence of fatal PE than those treated with ≥150 IU/kg/day (0.2% vs. 1.0%; p=0.004). Multivariate analysis confirmed that patients receiving <150 IU/kg/day LMWH had a lower risk for fatal PE (odds ratio [OR]: 0.2; 95% confidence interval [CI]: 0.06-0.8) and for major bleeding (OR: 0.6; 95% CI: 0.3-1.0) than those treated with ≥150 IU/kg/day. In real life, one in every two cancer patients with VTE received lower doses of LMWH than those used in randomised trials, with large variations from patient to patient. Unexpectedly, patients treated with <150 IU/kg/day LMWH had fewer fatal PE cases and fewer major bleeding events than those receiving ≥150 IU/kg/day LMWH. This finding, however, should be validated in prospective clinical trials.     

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.     

Predicting recurrences or major bleeding in women with cancer and venous thromboembolism. Findings from the RIETE Registry

BackgroundCancer patients with venous thromboembolism (VTE) have an increased incidence of recurrences and bleeding complications Reliable information on the factors determining the risk for such complications may facilitate better use of therapy.MethodsRIETE Registry is an ongoing, international registry of consecutive patients presenting with symptomatic acute VTE confirmed by objective tests. We assessed the 3-month outcome in all women with active cancer, trying to identify if differences exist according to the tumor site.ResultsUp to May 2007, 18,883 patients had been enrolled. Of them, 3805 (20%) had active cancer, 1719 (45%) were women. During the 3-month study period, 40 (2.3%) had recurrent deep vein thrombosis, 39 (2.3%) recurrent pulmonary embolism (PE), 67 (3.9%) major bleeding, 394 (23%) died. Of these, 13 (33%) women with recurrent PE died of the PE, 17 (42%) with major bleeding had fatal bleeding. In women with gastrointestinal (5.7% vs. 4.3%) or genitourinary (6.4% vs. 4.7%) cancers the incidence of bleeding complications exceeded that of VTE recurrences, while in those with brain (3.4% vs. 13%) or lung cancer (2.6% vs. 11%) the rate of recurrences outweighed that of major bleeding.ConclusionsWe identified significant differences in outcome according to the site of cancer that may help to identify those women with cancer and VTE at a higher risk for recurrences or major bleeding.     

Venous thromboembolism and bleeding after total knee and hip arthroplasty. Findings from the Spanish National Discharge Database

The impact of venous thromboembolism (VTE) and bleeding in patients undergoing major joint surgery has not been thoroughly studied. The Spanish National Discharge Database during the years 2005-2006 was used to assess the frequency and clinical impact of VTE and bleeding after elective total knee (TKA) or hip (THA) arthroplasty. Of 58,037 patients undergoing TKA, 0.18% (95% confidence interval [CI]: 0.15-0.22) were diagnosed with pulmonary embolism (PE), 0.57% (95% CI: 0.51-0.63) with deep-vein thrombosis (DVT), 1.20% (95% CI: 1.12-1.30) had bleeding complications, and 0.09% (95% CI: 0.07-0.12) died. Of 54 patients who died, 20.4% (95% CI: 10.7-35.4) had been diagnosed with PE, 3.70% (95% CI: 0.63-11.7) with DVT, and 13.0% (95% CI: 5.67-25.6) had bled. Of 31,769 patients undergoing elective THA, 0.23% (95% CI: 0.18-0.29) were diagnosed with PE, 0.44% (95% CI: 0.37-0.52) with DVT, 1.21% (95% CI: 1.10-1.34) bled, and 0.16% (95% CI: 0.12-0.21) died. Of 52 patients who died, 13.5% (95% CI: 6.08-24.8) had been diagnosed with PE, and 9.61% (95% CI: 3.52-21.3) had bled. On multivariable analysis, PE (odds ratio [OR]: 157; 95% CI: 75-328), DVT (OR: 6.3; 95% CI: 1.5-27) and bleeding (OR: 8.5; 95% CI: 3.6-20) were independent predictors for death after TKA. After THA, only PE (OR: 65; 95% CI: 26-160) and bleeding (OR: 6.4; 95% CI: 2.3-17) predicted the risk for death. Bleeding, DVT, and PE, arising after TKA were all independent predictors for death. Their increase in risk was, however, substantially higher for PE. After THA, only PE and bleeding independently predicted death.     

Major bleedings in the comparisons between low-molecular weight heparin versus oral anticoagulant therapy for venous thromboembolism

To evaluate the safety (major bleedings) of long-term treatment of symptomatic venous thromboembolism (VTE) using low molecular weight heparin (LMWH) compared with oral anticoagulant therapy (OAT) given for at least 3 months, we analyzed 10 randomized clinical trials enrolling a total of 2817 patients with objectively diagnosed symptomatic deep vein thrombosis, pulmonary embolism or both. The relative risk (RR, incidence of recurrent symptomatic VTE) was combined across the studies, using the inverse variance and the Mantel-Haenszel method. During treatment, major bleeding complications occurred in 2.8% of the patients in the LMWH arm versus 4% in the OAT arm: no statistically significant difference was observed (p=0.31). No differences in major bleeding were registered in the additional 3-9 months of follow-up (p=0.98). Long-term treatment with LMWH does not seem to be significantly safer than OAT. However, no conclusive interpretation from different studies with different designs is possible.     

Prospective study on the usefulness of lung scan in patients with deep vein thrombosis of the lower limbs

BACKGROUND: Asymptomatic pulmonary embolism (PE) is a common finding in patients with deep venous thrombosis (DVT) of the lower limbs, but the usefulness of seeking for silent PE in patients with acute DVT has not been evaluated. PATIENTS AND METHODS: This was a prospective study involving consecutive patients with acute symptomatic proximal DVT (confirmed by objective methods) and no clinical suspicion of PE. All patients underwent chest X-ray, ventilation-perfusion lung scan and arterial blood gases on admission, and received anticoagulant therapy. Those with scintigraphic evidence of PE underwent repeated lung scan and blood gases 7 days later. The aim of the study was to assess how many patients with silent PE develop symptoms while on heparin therapy, and in how many of them such symptoms are due to recurrent PE. RESULTS: 946 consecutive patients with acute, proximal DVT had no contraindications to full-dose anticoagulant therapy. Baseline lung scan revealed high-probability defects (silent PE) in 200 (21%). Seven of these 200 patients had symptomatic recurrences during the 7-day study period, and an inferior vena cava filter was inserted. Besides, 6 patients developed PE symptoms, but no new perfusion defects were found on repeated scan. They switched to coumarin therapy, and they did not develop any further complications. CONCLUSIONS: Lung scan in patients with symptomatic DVT and no clinical suspicion of PE may be useful, since some patients with silent PE may develop symptoms while on heparin therapy. Without a baseline scintigraphy all these patients would have been considered to have recurrent PE, and vena cava interruption could have been performed.     

Venous thromboembolism during pregnancy or postpartum: findings from the RIETE Registry

Venous thromboembolism (VTE) occurs infrequently during pregnancy, and issues concerning its natural history, prevention and therapy remain unresolved. RIETE is an ongoing registry of consecutive patients with objectively confirmed, symptomatic acute VTE. In this analysis, we compared the clinical characteristics and outcome for all enrolled pregnant and postpartum women with acute VTE, and all non-pregnant women in the same age range. Up to May 2005, 11,630 patients were enrolled in RIETE, of whom 848 (7.3%) were women aged <47 years. Of them, 72 (8.5%) were pregnant, 64 (7.5%) postpartum. Pregnant women presented less often with symptomatic pulmonary embolism (11%) than non-pregnant women (39%). VTE developed during the first trimester in 29 (40%) pregnant patients; in the second in 13; in the third in 30. Thrombophilia tests were more often positive in women who had VTE during the first trimester (odds ratio [OR]: 4.4; 95% CI: 0.9-2.4; p=0.037). Most patients in all three groups were initially treated with low-molecular-weight heparin (LMWH). As for long-term therapy, 75% of pregnant women received LMWH until delivery. There were no maternal deaths, and no pregnant patient had recurrence or bled before delivery. However, after delivery one patient (1.4%) developed recurrent thrombosis, four (5.6%) had major bleeding. In conclusion, VTE developed during the first trimester in 40% of the pregnant women, thus suggesting that thromboprophylaxis, when indicated during pregnancy, should start in the first trimester. No patient showed recurrence or bled before delivery, but after delivery the risk of bleeding exceeded the risk of recurrences.     

Prognostic factors for recurrence of venous thromboembolism (VTE) or bleeding during long-term secondary prevention of VTE with ximelagatran

The oral direct thrombin inhibitor ximelagatran (24 mg twice daily) has been shown to significantly reduce the incidence of recurrent venous thromboembolism (VTE) vs. placebo over 18 months, with no significant influence on bleeding (THRIVE III). The influence of potential prognostic factors on the risk of recurrent VTE or major and/or minor bleeding and their impact on ximelagatran treatment was evaluated in the THRIVE III study population. The effect of sex, age, body weight, renal function, malignancy, type of initial VTE event, and history of previous VTE events was investigated in the intention-to-treat population using Cox proportionate hazard modelling. Ximelagatran was administered to 612 patients and placebo to 611 patients. Within the placebo group, risk of recurrent VTE was higher among men than women (hazard ratio [HR]: 2.50,95% confidence interval [CI] 1.49,4.17), and in patients with one or more than one previous VTE event (HR: 1.73,95% CI 1.00, 2.99). There was a higher risk of bleeding among women than men in both the ximelagatran (HR: 1.49, 95% CI 1.06, 2.09) and placebo (HR: 1.48, 95% CI 1.01, 2.15) groups, and in placebo-treated patients with an initial pulmonary embolism (HR: 1.53, 95% CI 1.06,2.23) compared to those with initial deep vein thrombosis. There were no significant interactions between treatment effect and any of the potential prognostic factors. In conclusion, the superior efficacy of ximelagatran vs. placebo was maintained in all subgroups. Long-term use of oral ximelagatran, without coagulation monitoring or dose adjustment, should be feasible and well tolerated in a wide cross-section of patients for the secondary prevention of VTE.     

What is the optimal pharmacological prophylaxis for the prevention of deep-vein thrombosis and pulmonary embolism in patients with acute ischemic stroke?

BACKGROUND: Pulmonary embolism after acute ischemic stroke (AIS) is associated with a high in-hospital mortality. The benefit from pharmacological prophylaxis for venous thromboembolism (VTE) is uncertain probably due to doubts about the optimal agent and dose. We evaluated the benefit/risk ratio of different anticoagulant regimens in the prevention of VTE in patients with AIS. METHODS: The MEDLINE, EMBASE, and Cochrane Library databases were searched up to January 2005. Randomized controlled trials (RCT) comparing early administration of either low-molecular-weight heparin (LMWH) or unfractionated heparin (UFH) with control were included. Endpoints were objectively diagnosed deep-vein thrombosis (DVT), pulmonary embolism, intracranial hemorrhage (ICH), and extracranial hemorrhage (ECH). Low-dose UFH was arbitrarily defined as < or =15,000 IU/day, low-dose LMWH as < or =6000 IU/day or weight-adjusted dose of < or =86 IU/kg/day. RESULTS: Sixteen trials involving 23,043 patients with AIS met the inclusion criteria. The number of events was small and different doses of anticoagulant treatment were used. Compared to control, high-dose UFH was associated with a reduction in pulmonary embolism (OR=0.49, 95% confidence interval (CI)=0.29-0.83), but also with an increased risk of ICH (OR=3.86, 95% CI=2.41-6.19) and ECH (OR=4.74, 95% CI=2.88-7.78). Low-dose UFH decreased the thrombosis risk (OR=0.17, 95% CI=0.11-0.26), but had no influence on pulmonary embolism (OR=0.83, 95% CI=0.53-1.31); the risk of ICH or ECH was not statistically significant increased (OR=1.67, 95% CI=0.97-2.87 for ICH; and OR=1.58, 95% CI=0.89-2.81 for ECH, respectively). High-dose LMWH decreased both DVT (OR=0.07, 95% CI=0.02-0.29) and pulmonary embolism (0.44, 95% CI=0.18-1.11), but this benefit was offset by an increased risk for ICH (OR=2.01, 95% CI=1.02-3.96) and ECH (OR=1.78, 95% CI=0.99-3.17). Low-dose LMWH reduced the incidence of both DVT (OR=0.34, 95% CI=0.19-0.59) and pulmonary embolism (OR=0.36, 95% CI=0.15-0.87), without an increased risk of ICH (OR=1.39, 95% CI=0.53-3.67) or ECH (OR=1.44, 95% CI=0.13-16). For low-dose LMWH, the numbers needed to treat were 7 and 38 for DVT and pulmonary embolism, respectively. CONCLUSIONS: Indirect comparison of low and high doses of UFH and LMWH suggests that low-dose LMWH have the best benefit/risk ratio in patients with acute ischemic stroke by decreasing the risk of both DVT and pulmonary embolism, without a clear increase in ICH or ECH.     

Apixaban versus enoxaparin in patients with total knee arthroplasty. A meta-analysis of randomised trials

It was the objective of this study to systematically compare the effects of apixaban versus enoxaparin in patients following total knee arthroplasty (TKA). A systematic search of Medline, EMBASE, Cochrane Central Register of Controlled Trials was conducted. Eligible studies were prospective, randomised control trials (RCT) of apixaban therapy, comparing with enoxaparin, in patients who have a high risk of venous thromboembolism (VTE) after TKA. Three RCTs involving 7,337 individuals were identified, of whom 4,057 were treated with apixaban 2.5 mg once daily, and 3280 were subcutaneous enoxaparin (40 mg once-daily or 30 mg twice-daily). Meta-analysis demonstrated the odds ratio (OR) for the composite of major VTE (proximal deep-vein thrombosis and pulmonary embolism) for apixaban versus enoxaparin was 0.47 (95% confidence interval [CI]: 0.27 to 0.82, 0.6% vs. 1.2%) and 2.09 (95%CI: 0.99 to 4.45, 0.6% vs. 0.3%), respectively. All-cause mortality occurred in 0.2% of the apixaban group versus 0.09% of the enoxaparin group (OR=1.74; 95%CI, 0.51 to 5.95). With respect to safety outcomes, apixaban was associated with a lower major bleeding rate than enoxaparin (OR=0.55, 95%CI: 0.32 to 0.96). No significant differences were detected between two strategies in other endpoints of safety profile analysed: clinically relevant non-major bleeding, raised hepatic transaminase enzyme or bilirubin concentrations and arterial thromboembolic events. In conclusion, apixaban is non-inferior to subcutaneous enoxaparin when used for the same duration, with considerable advantage regarding safety profile of major bleeding after TKA.     

Treatment of venous thromboembolism in cancer patients

The management of deep vein thrombosis (DVT) and pulmonary embolism (PE) in patients with cancer can be a clinical dilemma. Comorbid conditions, warfarin failure, difficult venous access, and a high bleeding risk are some of the factors that often complicate anticoagulant therapy in these patients. In addition, the use of central venous access devices is increasing but the optimal treatment of catheter-related thrombosis remains controversial. Unfractionated heparin (UFH) is the traditional standard for the initial treatment of venous thromboembolism (VTE) but low molecular weight heparins (LMWHs) have been shown to be equally safe and effective in hemodynamically stable patients. For long-term treatment or secondary prophylaxis, vitamin K antagonists remain the mainstay treatment. However, the inconvenience and narrow therapeutic window of oral anticoagulants make extended therapy unattractive and problematic. As a result, LMWHs are being evaluated as an alternative for long-term therapy. New antithrombotic agents are being tested in clinical trials and may have the potential to replace conventional treatment. The role of inferior vena cava filters in cancer patients remains ill defined but these devices remain the treatment of choice in patients with contraindications for anticoagulant therapy.     

Maternal smoking, obesity, and risk of venous thromboembolism during pregnancy and the puerperium: a population-based nested case-control study

BACKGROUND: Smoking and obesity are associated with adverse pregnancy outcomes. The aim of the present study was to examine the association between smoking, obesity (BMI>30), and risk for venous thromboembolism (VTE) during pregnancy and the puerperium. MATERIALS AND METHODS: In a population-based case-control study nested within a Danish cohort of 71,729 women, we identified 129 cases with VTE in pregnancy or the puerperium, and 258 pregnant non-VTE controls. We obtained data from medical records regarding current smoking status, BMI, and other covariates, and computed the odds ratios (OR) for VTE as a measure of relative risk. RESULTS: Smoking and obesity were associated with increased risk of VTE during pregnancy and the puerperium (adjusted OR 2.7 (95% CI: 1.5, 4.9) and 5.3 (95% CI: 2.1, 13.5), respectively). Obesity appeared to be associated with a higher risk of pulmonary embolism (adjusted OR: 14.9 (95% CI: 3.0, 74.8) than of deep venous thrombosis (adjusted OR: 4.4, 95% CI: 1.6, 11.9). CONCLUSION: Smoking and obesity are risk factors for VTE in pregnancy and the puerperium.     

Venous thromboembolism prevention with fondaparinux 1.5 mg in renally impaired patients undergoing major orthopaedic surgery. A real-world, prospective, multicentre, cohort study

Despite the need for effective and safe thromboprophylactic drugs for patients with renal impairment, clinical trial data on anticoagulant agents are limited in this population. The study aim was to assess in the real-world setting the use of the once-daily 1.5 mg reduced dosage regimen of fondaparinux available for this context. In this prospective cohort study, patients with a creatinine clearance (CrCl) of 20-50 ml/minute, undergoing total hip (THR) or knee (TKR) replacement or hip fracture surgery (HFS) received fondaparinux thromboprophylaxis. Main clinical outcomes were bleeding (major/clinically relevant non-major), symptomatic venous thromboembolism (VTE) and death. Overall, 442 patients (353 women; median age: 82 years; 39.4% in ASA class ≥3; mean ± SD CrCl: 39.0 ± 8.0 ml/minute; 78% with additional risk factors for bleeding), undergoing THR (43.7%), TKR (27.6%), or HFS (28.7%) received fondaparinux 1.5 mg for a mean ± SD duration of 16.0 ± 12.5 days. At postoperative day 10, the rates (95% confidence interval) of major bleeding, clinically relevant bleeding and symptomatic VTE were 4.5% (2.8-6.9), 0.5% (0.1-1.6) and 0.5% (0.05-1.62), respectively; no fatal bleeding, bleeding into a critical organ, pulmonary embolism or proximal deep-vein thrombosis occurred. Corresponding rates at one month were 5.2%, 0.7% and 0.7%. One-month mortality was 2.3% (0.9-3.6). This large clinical prospective study provides for the first time, under conditions reflecting "real-world" routine clinical practice, data on the bleeding and VTE risks of thromboprophylaxis with fondaparinux 1.5 mg after major orthopaedic surgery in renally impaired patients. It shows that these patients constitute a very elderly and fragile population.     

Efficacy and Safety of Anticoagulant Therapy for the Treatment of Acute Cancer-Associated Thrombosis: A Systematic Review and Meta-Analysis

Background

Current clinical practice guidelines all recommend the use of therapeutic doses of low molecular weight heparins (LMWH) for the initial and long-term treatment of cancer-related thrombosis. The use of vitamin-K antagonists (VKA) is acceptable if LMWH is not available. Direct oral anticoagulants (DOACs) have been shown to be comparable to conventional therapy for the acute treatment of VTE but their efficacy and safety in cancer patients remains uncertain.

Methods

A systematic literature search strategy was conducted using MEDLINE, EMBASE, and the EBM reviews. Randomized controlled trials (RCTs) reporting rates of recurrent VTE and major bleeding in cancer patients were included. Relative risks (RR) (95% confidence intervals (CI)) for these outcomes were generated.

Results

A total of 9 RCTs (2310 patients) were included in our analysis. In comparison to VKA, LMWH showed a significant reduction in recurrent VTE events (RR: 0.52; 95% CI: 0.36 to 0.74) whereas DOACs did not (RR: 0.66; 95% CI: 0.39 to 1.11). LMWH was associated with a non significant increase in the risk of major bleeding (RR: 1.06; 95% CI: 0.5 to 2.23) whereas DOACs showed a non significant reduction (RR: 0.78; 95% CI: 0.42 to 1.44). Annualized risks of recurrent VTE and major bleeding among patients randomized to VKA were higher in the LMWH studies as compared to the studies assessing DOACs suggesting that a higher risk cancer population were enrolled in the LMWH studies.

Conclusions

LMWH should be used for the treatment of acute cancer-associated thrombosis. The use DOACs cannot be supported until trials comparing them to LMWH are conducted.     

Death due to recurrent thromboembolism among younger healthier individuals hospitalized for idiopathic pulmonary embolism

The incidence of death due to recurrent pulmonary embolism (PE) after a first-time idiopathic PE is not well defined. We conducted a retrospective study of patients age 18 to 56 years who had idiopathic PE between 1994-2001. The incidence and cause of death within five years was determined using linked discharge records and a master death registry. A total of 3,456 patients had a first-time idiopathic PE. The rate of recurrent VTE 0-6 months after the index event was 13.1%/year, and 2.9%/year 6-60 months after the event. During the mean follow-up of 3.2 years 118 (3.4%, 95% confidence interval [CI] = 2.8-4.1%) patients died. Fifty-two (44%) deaths occurred <29 days after the index PE (case-fatality rate = 1.5%, 95%CI = 1.1-2.0%). Among the 66 cases (1.9%) that died after 28 days, 18 (0.52%) were due to recurrent PE or its sequelae: eight had recurrent PE alone, five had recurrent PE and a serious co-morbid illness, and five had thromboembolic pulmonary hypertension with or without acute PE. The person-time rate of death (deaths per 100 patient-years) attributed to any recurrent thromboembolism 6-60 months after the event was 0.16% (95%CI = 0.1-0.26%). Ten of the 18 (56%) late thromboembolic deaths reflected a first-time recurrent PE. The 28-day case-fatality rate for recurrent VTE was 2.8% (95%CI = 1.5-4.9%). In this cohort of younger patients with idiopathic PE, the rate of death due to recurrent VTE, particularly to first-time recurrent PE, was low. Among the patients who died of thromboembolism >28 days after the index PE, 28% had developed pulmonary hypertension.