Prevention of venous thromboembolism in medical patients with enoxaparin: a subgroup analysis of the MEDENOX study

NOACs for thromboprophylaxis in medical patients

The risk of venous thrombosis extends for an indeterminate length of time following admission to hospital with a medical or surgical condition. Observational studies in surgery show this risk extends for months and perhaps more than one year, for medical patients the risk extends for at least several weeks. Large bodies of evidence support the heightened risk status of hospitalised surgical and medical patients, and that prophylactic measures significantly reduce the risk of thrombosis. Extending thromboprophylaxis for 4-6 weeks with anticoagulants both old and new has been shown to be efficacious and safe in surgical patients. However in populations of medical patients although prolonged anticoagulant thromboprophylaxis has been shown to be efficacious it also results in more bleeding and the risk benefit is not clear. Hence no therapies are approved for prolonged thromboprophylaxis in medical patients. In this area there have been one phase III study of low molecular weight heparin and two completed phase III studies of NOACs. This article briefly summarises our understanding of the background to preventing venous thromboembolism in hospitalised medical patients and reviews the details of the studies using NOACs.

Mechanisms and impact of the frequent exacerbator phenotype in chronic obstructive pulmonary disease

Exacerbations of chronic obstructive pulmonary disease (COPD) are important events that carry significant consequences for patients. Some patients experience frequent exacerbations, and are now recognized as a distinct clinical subgroup, the 'frequent exacerbator' phenotype. This is relatively stable over time, occurs across disease severity, and is associated with poorer health outcomes. These patients are therefore a priority for research and treatment. The pathophysiology underlying the frequent exacerbator phenotype is complex, with increased airway and systemic inflammation, dynamic lung hyperinflation, changes in lower airway bacterial colonization and a possible increased susceptibility to viral infection. Frequent exacerbators are also at increased risk from comorbid extrapulmonary diseases including cardiovascular disease, gastroesophageal reflux, depression, osteoporosis and cognitive impairment. Overall these patients have poorer health status, accelerated forced expiratory volume over 1 s (FEV1) decline, worsened quality of life, and increased hospital admissions and mortality, contributing to increased exacerbation susceptibility and perpetuation of the frequent exacerbator phenotype. This review article sets out the definition and importance of the frequent exacerbator phenotype, with a detailed examination of its pathophysiology, impact and interaction with other comorbidities.

Evolution of heparin anticoagulants to ultra-low-molecular-weight heparins: a review of pharmacologic and clinical differences and applications in patients with cancer

The burden of venous thromboembolism (VTE) is high in patients with cancer, particularly those with metastatic disease and those receiving chemotherapy. The use of heparin and heparin derivatives should be considered for primary prevention of VTE in hospitalized patients with cancer and in patients undergoing cancer surgery. Preliminary evidence also suggests that heparins may have direct anticancer benefits owing to effects on tumor growth, angiogenesis, and metastasis. Despite the potential benefits of heparin-derived anticoagulants, many at-risk patients do not receive adequate thromboprophylaxis. The evolution of unfractionated heparin to low-molecular-weight and ultra-low-molecular-weight heparins has provided practitioners with alternatives for VTE prevention in cancer, although these alternatives present challenges related to clinically relevant pharmacologic differences between agents. In this review, we present results from our review of the medical literature focusing on the use of the heparin-derived anticoagulants in prospective interventional studies of primary thromboprophylaxis in patients with cancer in surgical, hospitalized, and ambulatory settings.

Routine pharmacological venous thromboembolism prophylaxis in frail older hospitalised patients: where is the evidence?

It has been claimed that there are over 25,000 preventable in-hospital deaths from venous thromboembolism annually in the UK. NICE and SIGN guidelines therefore recommend that all hospitalised patients are risk assessed for venous thromboembolism. The guidelines would recommend using pharmacological thromboprophylaxis for all patients aged 60 and above with reduced mobility and acute medical illness unless obvious contra-indications exist. Meta-analysis data regarding pharmacological thromboprophylaxis for medical patients demonstrate reductions in asymptomatic deep vein thrombosis (DVT) rather than fatal pulmonary embolism and mortality. There is also the potential for increased bleeding risk with this approach. Evidence for older medical in-patients, particularly those aged over 75, is more limited being derived from subgroup analyses of larger clinical trials. In addition, based on exclusion criteria such as increased bleeding risk, frailer older adults were unlikely to have been included within such trials. This commentary will (i) critically appraise available data on the incidence of DVT and PE in older hospitalised patients; (ii) review the evidence available from meta-analyses and subgroup analyses in older medical in-patients for the use of venous thromboembolism prophylaxis; (iii) discuss those situations out-with the guidelines where venous thromboprophylaxis may not be appropriate and even potentially harmful in this patient group and (iv) suggest future research directions.

Anticoagulation; New Pharmacologic Methods to Prevent Venous Thromboembolism in Older Adults: A Meta-Analysis

OBJECTIVE

To conduct a meta-analysis of randomized controlled trials that used newly approved drugs to prevent venous thromboembolism (VTE) in older adults.

DATA SOURCES

PubMed, EMBASE, and International Pharmaceutical Abstracts (through July 2012).

STUDY SELECTION AND DATA EXTRACTION

Full-text clinical trial reports were included if they (1) had a randomized controlled design, (2) used a pharmacologic method approved or anticipated to be approved in the US, (3) enrolled at least 300 subjects, (4) enrolled subjects with a mean age of 65 years or older or performed a subgroup analysis in adults in that population, and (5) scored at least 7 of 8 on quality criteria for clinical trials. Twenty unique studies met the inclusion criteria.

DATA SYNTHESIS

The most common indications for pharmacologic VTE prophylaxis in the identified studies were orthopedic procedures involving the lower extremities and general surgery. Only 2 studies enrolled acutely ill patients admitted to hospital medical services. Fondaparinux (5 studies) was more effective than enoxaparin in preventing VTE (OR 0.5, 95% CI 0.37–0.67; p < 0.00001) but had more bleeding (OR 1.48, 95% CI 1.05–2.08; p = 0.03). Dabigatran 150 mg once daily (3 studies) was less effective than enoxaparin in preventing VTE (OR 1.30, 95% CI 1.09–1.56; p = 0.004) with a similar bleeding risk (OR 0.74, 95% CI 0.46–1.22; p = 0.24). Dabigatran 220 mg once daily (4 studies) was as effective as enoxaparin in preventing VTE (OR 1.02, 95% CI 0.83–1.26; p = 0.84) and had similar bleeding (OR 1.08, 95% CI 0.66–1.76; p = 0.76). Rivaroxaban (4 studies) was more effective than enoxaparin in preventing VTE (OR 0.38, 95% CI 0.23–0.61; p < 0.0001) with a trend toward a higher rate of bleeding (OR 1.8, 95% CI 0.90–3.60; p = 0.09). Apixaban (5 studies) was more effective than enoxaparin in preventing VTE (OR 0.64, 95% CI 0.43–0.96; p = 0.0002) and had a similar rate of bleeding (OR 0.71, 95% CI 0.42–1.21; p = 0.21).

CONCLUSIONS

When compared to enoxaparin, newer drugs exhibit slightly different safety and efficacy profiles when used for VTE prevention in older adults undergoing major orthopedic surgery. There are insufficient data for other indications. The benefits and risks of new pharmacologic methods of VTE prevention are unclear in the oldest old (age ≥85 years) and in those admitted to a hospital for an acute medical illness or to a skilled nursing facility.

Venous thromboembolism and the utility of the Padua Prediction Score in patients with sepsis admitted to internal medicine departments

BACKGROUND

Sepsis is prevalent in internal medicine (IM) departments. Elderly patients with sepsis and chronic medical conditions are at an increased risk for venous thromboemolism (VTE). The objective of this study was to assess the rate of VTE and the accuracy of the Padua Prediction Score (PPS) to predict VTE in patient with sepsis admitted to IM departments.

METHODS

We prospectively collected data on septic patients admitted to IM departments in a community-based medical center. Additionally, we retrospectively collected VTE risk factors and events throughout a 1-year post hospitalization period. We computed the PPS for every patient, and analyzed the data accordingly.

RESULTS

In total, 1080 patients were included in the study. The mean age was 74.68 ± 16.1 years. The average PPS was 4.86 ± 2.26, and 71.2% of the patients had a positive PPS. Only 17.8% of the patients received anticoagulant prophylaxis during their hospital stay. Seven patients had VTE on admission, 14 (1.29%) acquired in-hospital VTE, and 7 (0.65%) had VTE post discharge throughout 1 year. In all, 21.9% patients died during hospitalization, and the overall survival rate was 64%. PPS was not correlated with anticoagulant administration (P = 0.36), in-hospital VTE (P = 0.23) or 1-year VTE (P = 0.40), but was significantly associated with in-hospital death and survival (P < 0.0001).

CONCLUSION

The rate of VTE in medical patients with sepsis in IM departments is low, and PPS lacks granularity in detecting patients at risk of acquiring it. In this population, a positive PPS is highly associated with death, and may reflect a more general co-morbidity and disease severity index.

Cancer-associated thrombosis

Cancer-associated thrombosis accounts for almost one-fifth of all cases of venous thromboembolism (VTE) and is a leading cause of death, morbidity, delays in care, and increased costs. Our understanding of risk factors for cancer-associated thrombosis has expanded in recent years, and investigators have begun to use biomarkers and clinical prediction models to identify those cancer patients at greatest risk for VTE. The Khorana Risk Model, which is based on easily obtained biomarkers and clinical factors, has now been validated in several studies. Recent clinical trials of prophylaxis and treatment of VTE in cancer patients are reviewed here. In addition, consensus guidelines and expert opinion regarding management of VTE in specific challenging situations are presented.

Thromboprophylaxis in non-surgical cancer patients

Acutely ill medical patients with cancer and cancer patients requiring non-surgical therapy are considered as non-surgical cancer patients and are at moderate to high risk of venous thromboembolism (VTE): approximately 10-30% of these patients may develop asymptomatic or symptomatic deep-vein thrombosis (DVT) or pulmonary embolism (PE), and the latter is a leading contributor to deaths in hospital. Other medical conditions associated with a high risk of VTE include cardiac disease, respiratory disease, inflammatory bowel disease, rheumatological and infectious diseases. Pre-disposing risk factors in non-surgical cancer patients include a history of VTE, immobilisation, history of metastatic malignancy, complicating infections, increasing age, obesity hormonal or antiangiogenic therapies, thalidomide and lenalidomide therapy. Heparins, both unfractionated (UFH) and low molecular weight heparin (LMWH) and fondaparinux have been shown to be effective agents in prevention of VTE in the medical setting with patients having a history of cancer. UFH and LMWH along with semuloparin also have a role in outpatients with cancer receiving chemotherapy. However, it has not yet been possible to demonstrate a significant effect on mortality rates in this population. UFH has a higher rate of bleeding complications than LMWH. Thromboprophylaxis has been shown to be effective in medical patients with cancer and may have an effect on cancer outcomes. Thromboprophylaxis in patients receiving chemotherapy remains controversial and requires further investigation. There is no evidence for the use of aspirin, warfarin or mechanical methods. We recommend either LMWH, or fondaparinux for the prevention of VTE in cancer patients with acute medical illnesses and UFH for those with significant severe renal impairment. For ambulatory cancer patients undergoing chemotherapy we recommend LMWH or semuloparin. These are safe and effective agents in the thromboprophylaxis of non-surgical cancer patients.

Anticoagulants in cancer

Cancer patients are at high risk for venous thromboembolism (VTE), which results in substantial morbidity and mortality. In this narrative review, we present evidence for the use of anticoagulants in the treatment and prevention of VTE in cancer patients. The benefit of perioperative anticoagulant prophylaxis following cancer surgery is well established. However, the risk-benefit trade-offs in non-surgical hospitalized cancer patients and among outpatients receiving chemotherapy are more complex. Emerging evidence suggests that the use of low molecular weight heparin (LMWH) may confer a small survival benefit in cancer patients without VTE. However, specific patient populations that may derive the most benefit have yet to be defined. Guidelines endorse LMWH as the preferred treatment for acute VTE, on the basis of high-quality clinical trial data, but the optimal duration of treatment remains unclear, and practical issues may limit its use outside the clinical trial setting. Novel oral anticoagulants may provide additional treatment and prophylaxis options, but their efficacy and safety in this population have not been established. Despite the significant impact of VTE on the lives of cancer patients and the large body of existing literature regarding treatment and prevention, important unanswered clinical questions remain, emphasizing the need for additional high-quality clinical trial data.

Incidence and predictors of venous thromboembolism (VTE) among ambulatory patients with lung cancer

BACKGROUND

The incidence and economic impact of lung cancer-associated venous thromboembolic (VTE) events in a contemporary ambulatory setting is unknown.

PATIENTS AND METHODS

We conducted a retrospective cohort analysis utilizing the IMS Patient-Centric database of US healthcare claims and recorded VTE events occurring 3-12 months after chemotherapy initiation.

RESULTS

Lung cancer (n=6732) and control (n=17 284) cohorts had 51% women, with a mean age of 64 years. VTE occurred in 13.9% of the lung cancer cohort (odds ratio [OR], 3.15; 95% confidence interval [CI] 2.55, 3.89), and 1.4% of the control cohort (P<0.0001). Charlson Comorbidity Index ≥ 5 (CCI; OR, 2.56; 95% CI 1.02, 6.39; P=0.045), the use of erythropoiesis-stimulating agents (ESAs; OR, 1.63; 95% CI 1.40, 1.89; P<0.0001), and congestive heart failure (CHF; OR, 1.29; 95% CI 1.01, 1.66; P=0.045) were associated with VTE. Bleeding occurred in 22.1% of the lung cancer cohort and 7.0% of the control cohort (P<0.0001). Among lung cancer patients the average total healthcare payment was $84,187 in patients with VTE compared to $56,818 in patients without VTE (P<0.0001).

CONCLUSIONS

VTE is common among lung cancer patients receiving chemotherapy and is associated with increased healthcare utilization.

How I manage venous thromboembolism risk in hospitalized medical patients

Venous thromboembolism is a significant cause of illness and death worldwide. Large bodies of evidence support the heightened risk status of hospitalized medical patients, and that prophylactic measures significantly reduce the risk of thrombosis, yet these patients often fail to receive adequate prophylactic therapy. This failure may be accounted for by a lack of awareness of the relevant indications, poorly designed implementation systems, and clinical concerns over the side effects of anticoagulant medications. This article briefly summarizes our understanding of the clinical factors relevant to the evaluation of venous thromboembolism risk in hospitalized medical patients. We describe our approach to the use of thromboprophylaxis, through which we aim to minimize the disease burden of this under-recognized and preventable pathology.

Preventing venous thromboembolism in hospitalized patients with cancer: improving compliance with clinical practice guidelines

PURPOSE

The use of anticoagulants for the prevention of venous thromboembolism (VTE) in hospitalized medical and surgical oncology patients is discussed.

SUMMARY

Hospitalized patients are often at risk for developing VTE, and risk is increased in patients who have cancer. Moreover, the incidence of VTE appears to be rising in hospitalized cancer patients, who have a 2.2-fold increased risk of mortality with a VTE compared with similar patients without VTE. The literature indicates that these patients are often inadequately anticoagulated, despite strong recommendations for prophylaxis. Although there are few studies that specifically address VTE prophylaxis in cancer patients, there are several large trials that have examined data in cancer subgroups. The trials have directly compared low-molecular-weight heparin (LMWH) with placebo, unfractionated heparin with LMWH, factor Xa inhibitor (fondaparinux) with placebo, and fondaparinux with LMWH. Three important guidelines provide current recommendations for VTE prophylaxis; the American Society of Clinical Oncology (ASCO), the National Comprehensive Cancer Network (NCCN), and the American College of Chest Physicians (ACCP) recommend unfractionated heparin, LMWH, or fondaparinux for VTE prophylaxis when there are no contraindications. Pharmacists can play an essential role in ensuring that VTE prophylaxis is appropriate for individual patients. Interventions to improve compliance with guidelines are particularly important now due to financial incentives from quality-focused organizations whose mandate is to decrease preventable mortality events in hospitals.

CONCLUSION

Hospitalized patients with cancer often do not receive appropriate thromboprophylaxis. Guidelines from ASCO, ACCP, and NCCN recommend unfractionated heparin, an LMWH, or fondaparinux for VTE prophylaxis when there are no contraindications to such therapy.

Acute infections and venous thromboembolism

BACKGROUND

Data on the association between acute infections and venous thromboembolism (VTE) are sparse. We examined whether various hospital-diagnosed infections or infections treated in the community increase the risk of VTE.

METHODS

We conducted this population-based case-control study in Northern Denmark (population 1.8 million) using medical databases. We identified all patients with a first hospital-diagnosed VTE during the period 1999-2009 (n = 15 009). For each case, we selected 10 controls from the general population matched for age, gender and county of residence (n = 150 074). We identified all hospital-diagnosed infections and community prescriptions for antibiotics 1 year predating VTE. We used odds ratios from a conditional logistic regression model to estimate incidence rate ratios (IRRs) of VTE within different time intervals of the first year after infection, controlling for confounding.

RESULTS

Respiratory tract, urinary tract, skin, intra-abdominal and bacteraemic infections diagnosed in hospital or treated in the community were associated with a greater than equal to twofold increased VTE risk. The association was strongest within the first 2 weeks after infection onset, gradually declining thereafter. Compared with individuals without infection during the year before VTE, the IRR for VTE within the first 3 months after infection was 12.5 (95% confidence interval (CI): 11.3-13.9) for patients with hospital-diagnosed infection and 4.0 (95% CI: 3.8-4.1) for patients treated with antibiotics in the community. Adjustment for VTE risk factors reduced these IRRs to 3.3 (95% CI: 2.9-3.8) and 2.6 (95% CI: 2.5-2.8), respectively. Similar associations were found for unprovoked VTE and for deep venous thrombosis and pulmonary embolism individually.

CONCLUSIONS

Infections are a risk factor for VTE.

Prevention and treatment of venous thromboembolism in patients with cancer

Venous thromboembolism (VTE) is the second leading cause of death and a major cause of morbidity in patients with cancer. Pharmacologic thromboprophylaxis is recommended in all hospitalized cancer patients without contraindications to anticoagulants. The role of thromboprophylaxis in outpatients undergoing chemotherapy is less certain because of the diversity of the tumor types and their associated risks of VTE and bleeding. Thromboprophylaxis should only be considered in patients at high risk for VTE. Cancer patients with a newly diagnosed VTE should be preferably treated with low-molecular-weight heparin for a minimum of 3-6 months. Treatment duration should be individualized based on the clinical status and stage of the cancer, the risk of recurrent VTE, the risk of bleeding, and personal preference of the patient. Further research is required to assess the role of the new oral anticoagulants (direct Xa and thrombin inhibitors) for this high-risk population.

SEOM guidelines on thrombosis in cancer patients

The association between cancer and thrombosis is well established. Venous thromboembolism (VTE) is considered a main cause of mortality and morbidity in cancer patients and is commonly underestimated by oncologists. In recent years the incidence rates of VTE have notably increased. Several studies have clearly shown that cancer patients who are diagnosed with VTE present a poorer prognosis. The Spanish Society of Medical Oncology (SEOM) presents the guidelines for thrombosis and cancer in order to improve the prevention and management of VTE.

Enoxaparin in cardiovascular disease: how to improve effectiveness and safety?

The review analyses the specifics of enoxaparin therapy in the most prevalent cardiovascular diseases, such as acute coronary syndrome, venous thromboembolism, and atrial fibrillation. The decision strategy is presented for difficult and non-standard clinical situations (renal dysfunction, elderly age, heparin medication change, or abnormal body weight), when the optimal balance between effectiveness and safety requires modifying the standard treatment protocols.

Risk assessment models for cancer-associated venous thromboembolism

Venous thromboembolism (VTE) is common in cancer patients, and is associated with significant morbidity and mortality. Several factors, including procoagulant agents secreted by tumor cells, immobilization, surgery, indwelling catheters, and systemic treatment (including chemotherapy), contribute to an increased risk of VTE in cancer patients. There is growing interest in instituting primary prophylaxis in high-risk patients to prevent incident (first-time) VTE events. The identification of patients at sufficiently high risk of VTE to warrant primary thromboprophylaxis is essential, as anticoagulation may be associated with a higher risk of bleeding. Current guidelines recommend the use of pharmacological thromboprophylaxis in postoperative and hospitalized cancer patients, as well as ambulatory cancer patients receiving thalidomide or lenalidomide in combination with high-dose dexamethasone or chemotherapy, in the absence of contraindications to anticoagulation. However, the majority of cancer patients are ambulatory, and currently primary thromboprophylaxis is not recommended for these patients, even those considered at very high risk. In this concise review, the authors discuss risk stratification models that have been specifically developed to identify cancer patients at high risk for VTE, and thus might be useful in future studies designed to determine the potential benefit of primary thromboprophylaxis.

Pharmacologic prophylaxis for venous thromboembolism and 30-day outcomes among older patients hospitalized with heart failure: an analysis from the ADHERE national registry linked to Medicare claims

BACKGROUND

Hospitalized medically ill patients are at greater risk for venous thromboembolism (VTE). Although pharmacologic prophylaxis regimens have reduced VTE risk in medically ill patients, associations with early postdischarge adverse clinical outcomes among patients with heart failure are unknown.

HYPOTHESIS

We hypothesized that patients receiving pharmacologic VTE prophylaxis during hospitalization for heart failure would have lower rates of postdischarge adverse clinical outcomes than patients not receiving prophylaxis.

METHODS

Using data from the Acute Decompensated Heart Failure (ADHERE) registry linked to Medicare claims, we estimated 30-day postdischarge outcome rates for patients who received in-hospital subcutaneous heparin compared with patients who did not receive in-hospital VTE prophylaxis. We excluded patients who received warfarin or intravenous heparin. Outcomes included mortality, thromboembolic events, major adverse cardiovascular events, and all-cause readmission. We used propensity-score methods to estimate associations between VTE prophylaxis and each outcome. In a secondary analysis, we compared outcomes of patients receiving pharmacologic prophylaxis with unfractionated heparin (UFH) vs low-molecular-weight heparin (LMWH).

RESULTS

Of 36 799 eligible patients in 265 hospitals, 12 169 (33%) received pharmacologic VTE prophylaxis during the hospitalization. In unadjusted analysis and after weighting by the inverse probability of treatment, VTE prophylaxis was not associated with 30-day postdischarge mortality, thromboembolic events, major adverse cardiovascular events, or all-cause readmission. There were no differences in outcomes between patients receiving UFH and those receiving LMWH.

CONCLUSIONS

Pharmacologic VTE prophylaxis is provided to one-third of older patients hospitalized with heart failure. Treatment with LMWH or UFH did not have a statistically significant association with 30-day postdischarge outcomes.

Use of anticoagulants in elderly patients

Thromboembolic disorders are a major cause of morbidity and mortality, and the risk of thromboembolism increases with age. Anticoagulants are recommended for indications including the prevention of venous thromboembolism in surgical and medical patients, treatment of venous thromboembolism and stroke prevention in patients with atrial fibrillation. Traditional anticoagulants that have been used include unfractionated heparin, low molecular weight heparin, fondaparinux and vitamin K antagonists. However, these agents are all associated with drawbacks (i.e. parenteral administration or frequent coagulation monitoring/dose titration), and it has been particularly challenging to treat elderly patients with anticoagulants. Some specific characteristics of elderly patients may influence the safety of anticoagulant therapy, such as decreased renal function, co-morbidities and the use of multiple medications. The complexity of anticoagulation therapy and the increased risk of bleeding complications in elderly patients may prevent some physicians from prescribing anticoagulants to these patients, which leaves them at risk of thromboembolic events. Thus, safer and more convenient anticoagulants are needed, particularly for elderly patients. New oral anticoagulants have been developed in recent years and have shown promise in clinical studies that included elderly patients. These agents could simplify the management of thromboembolic disorders and improve the safety of anticoagulation.

Epidemiology, risk and outcomes of venous thromboembolism in cancer

Cancer is associated with a fourfold increased risk of venous thromboembolism (VTE). The risk of VTE varies according to the type of malignancy (i. e. pancreatic cancer, brain cancer, lymphoma) and its disease stage and individual factors (i. e. sex, race, age, previous VTE history, immobilization, obesity). Preventing cancer-associated VTE is important because it represents a significant cause of morbidity and mortality. In order to identify cancer patient at particularly high risk, who need thromboprophylaxis, risk prediction models have become available and are under validation. These models include clinical risk factors, but also begin to incorporate biological markers. The major American and European scientific societies have issued their recommendations to guide the management of VTE in patients with cancer. In this review the principal aspects of epidemiology, risk factors and outcome of cancer-associated VTE are summarized.

Venous thromboembolism in patients with heart failure

This review is focussed on the problem of venous thromboembolism in patients with heart failure (HF). The results of the major clinical trials of antithrombotic therapy in HF patients are presented. The authors discuss comparative effectiveness, safety, and tolerability of unfractionated heparins, low molecular weight heparins, and fondaparinux. The results of the two trials, MAGELLAN and ADOPT, are expected to clarify the clinical potential of such oral anticoagulants as rivaroxaban and apixaban (Factor Xa inhibitors). The problem of low rates e of preventive antithrombotic administration is emphasized.

Comparative assessment of low-molecular-weight heparins in cancer from the perspective of patient outcomes and survival

Patients with cancer are at high risk of developing venous thromboembolism (VTE), including deep venous thrombosis and pulmonary embolism. Compared to non-cancer patients, VTE in cancer is more frequently associated with clinical consequences, including recurrent VTE, bleeding, and an increase in the risk of death. Low-molecular-weight heparins (LMWHs) are commonly recommended for the prevention and treatment of VTE in cancer patients because of their favorable risk-to-benefit profile. Indeed, compared with vitamin K antagonists, LMWHs are characterized by a reduced need for coagulation monitoring, few major bleeding episodes, and once-daily dosing, which make these drugs more suitable in the cancer setting. Guidelines have been published recently with the aim to improve the clinical outcomes in cancer patients at risk of VTE and its complications. Coagulation activation in cancer may have a role not only in thrombosis but also in tumor growth and dissemination. Hence, inhibition of fibrin formation has been considered a possible tool against the progression of malignant disease. Clinical studies show that anticoagulant drugs may have a beneficial effect on survival in cancer patients, with a major role for LMWHs. Recently a number of prospective randomized clinical trials to test LMWHs to improve cancer survival as a primary endpoint in cancer patients have been conducted. Although the results are controversial, the interest in this research area remains high.

Certoparin versus UFH to prevent venous thromboembolic events in the very elderly patient: an analysis of the CERTIFY study

INTRODUCTION

There is an exponential rise of thromboembolic risk with age because of co-morbidities, immobility and pharmacotherapy. We aimed to investigate the benefits and risks of heparin prophylaxis in very elderly patients ≥80 years and the type of heparin used in a subgroup analysis of the CERTIFY trial.

PATIENTS/METHODS

3,239 patients were randomized to 3,000 U aXa o.d. certoparin or 5,000 IU t.i.d. unfractionated heparin (UFH) for 8-20 days.

RESULTS

Patients ≥80 years (n=1,365) were more likely to be female, had a lower mean bodyweight, were more frequently using antiplatelets and had a GFR below 30 ml/min/1.73 m(2) more often than patients <80 years (n=1,875). The combined endpoint of proximal DVT, symptomatic non-fatal PE and VTE related death was experience by 5.26% of patients ≥80 years versus 3.51% in younger patients (OR 1.53; 95%CI 1.05-2.21; p=0.03). There were no significant differences in both minor (OR 1.11; 95%CI 0.75-1.62) and major (OR 2.53; 95%CI 0.93-6.86) bleeding risks. Certoparin and UFH were equally effective in reducing thromboembolic risk in either age group. The risk of any (OR 0.45; 95%CI 0.26-0.79) and minor bleeding (OR 0.42; 95%CI 0.23-0.78) was reduced with certoparin in the very elderly only. There were more adverse events in elderly patients (OR 1.26; 95%CI 1.1-1.46), but rates were otherwise comparable.

CONCLUSIONS

The analysis confirmed the increased thromboembolic risk in very elderly patients, but demonstrated no increased bleeding risk. Certoparin and UFH were equally effective and safe with a reduced risk of minor bleeding complications with certoparin in the very elderly.

Impact of chemotherapy on thrombin generation and on the protein C pathway in breast cancer patients

Although thromboembolism is a problematic complication of chemotherapy, the pathogenic mechanisms by which chemotherapeutic agents exert prothrombotic effects in vivo are unclear.The objective of this study was to examine the effects of adjuvant chemotherapy on thrombin generation, the protein C anticoagulant pathway, and microparticle tissue factor (MP TF) activity in 26 breast cancer patients (stages I to III). The patients received cyclophosphamide, 5-fluorouracil, and methotrexate, epirubicin, or doxorubicin. Plasma samples were collected on day 1 (baseline), day 2, and day 8 for the first 2 cycles of chemotherapy. Levels of thrombin-antithrombin (TAT) complexes, MP TF activity, and components of the protein C anticoagulant pathway, including protein C, activated protein C (APC), soluble thrombomodulin (sTM), and soluble endothelial protein C receptor (sEPCR), were measured. Compared to prechemotherapy baseline levels, plasma TAT, protein C, and APC were significantly different following the administration of chemotherapy (p < 0.01 for each). Plasma TAT was higher in cycle 1, day 2, and cycle 2, day 8, compared to baseline. Plasma protein C levels were lower in cycle 2, day 8, whereas plasma APC levels were lower in cycle 2, day 1, and cycle 2, day 8. No significant changes were found in plasma sEPCR, sTM, or MP TF activity. This study suggests that adjuvant chemotherapy in women with breast cancer increases thrombin generation and impairs the endothelium-based protein C anticoagulant pathway.

Prevention of VTE in women with cancer

The prevention of venous thromboembolism (VTE) in women with cancer requires special consideration. The presence of cancer results in both non-surgical and surgical patients having increased risk of VTE. This usually leads to a modification of the recommended preventive therapy, affecting the type, dose and length of therapy. Cancer patients have other factors which may predispose them to bleeding. Prevention of VTE in cancer patients is important in a number of settings and has been investigated in many of these. These can be broadly classified into three areas: (1) Non-surgical patients in hospital and outpatient care: (1.1) Acutely ill medical patients with incidental cancer or with complications related to cancer; (1.2) Cancer patients receiving therapy--chemotherapy, hormonal therapy, radiotherapy. (2) Surgical care: (2.1) Surgical procedures for cancer therapy; (2.2) Surgical procedures for non-cancer indications in cancer patients. (3) Long-term prevention of VTE in otherwise well outpatients with cancer and its effect on mortality.