The metabolic syndrome and the risk of venous thrombosis: a case-control study

How I treat the co-occurrence of venous and arterial thromboembolism: anticoagulation, antiplatelet therapy, or both?

ABSTRACT

Arterial and venous thromboses are classically considered distinct disease states, with arterial thrombosis mediated predominantly by platelets and therefore, treated with antiplatelet therapy, and venous thrombosis mediated by the plasmatic coagulation system and treated with anticoagulation. However, co-occurrence of arterial and venous events is common, and there is increasing evidence of shared risk factors and pathophysiologic overlap. This presents a management challenge: does the patient with venous and arterial thrombosis, require anticoagulation, antiplatelet therapy, or both? Herein, we present a structured approach to the evaluation and management of patients with venous thrombosis who are also at risk for or have a history of an arterial thromboembolic event. We emphasize the importance of defining the indications for antithrombotic therapy, as well as the evaluation of factors that influence both thrombotic and bleeding risk, including disorder-specific and patient-specific factors, as well as the inherent risk balance of antithrombotic therapy regimens. We illustrate this approach in 4 cases, discussing the unique considerations and recent updates in the management of venous thrombosis, acute noncardioembolic ischemic stroke, coronary artery disease and acute myocardial infarction, and peripheral artery disease after revascularization.

Future risk of metabolic syndrome after recurrent pregnancy loss: a cohort study using UK Biobank

OBJECTIVE

To evaluate the risk of metabolic syndrome (MS) after recurrent pregnancy loss (RPL) using UK Biobank data. A history of pregnancy loss is associated with the development of cardiovascular diseases in the future. However, the association between RPL and subsequent MS is poorly understood. Therefore, we aimed to check the risk of MS after RPL.

DESIGN

The study population was divided into 2 groups according to reproductive history: women with a history of RPL and women without a history of RPL. Recurrent pregnancy loss was defined as 2 or more spontaneous miscarriages, and MS was defined as at least 3 of the following: abdominal obesity, hypertriglyceridemia, low high-density lipoprotein cholesterol levels, high-blood pressure, and hyperglycemia.

SETTING

UK Biobank resource.

PATIENTS

The UK Biobank is a prospective cohort study that enrolled individuals aged between 40 and 69 years whose medical and reproductive histories were retrieved at enrollment. In this cohort, only women with a history of at least one pregnancy were selected.

INTERVENTIONS

Recurrent pregnancy loss.

MAIN OUTCOME MEASURES

The primary outcome was the prevalence of MS. The secondary outcomes were 5 diagnostic components of MS.

RESULTS

We analyzed 228,674 women, including 15,702 with a history of RPL and 212,972 without a history of RPL. Women with a history of RPL have a higher prevalence of MS between the ages of 40 and 60 years (33.0% vs. 31.5%). After adjusting for covariates (age, race, number of live births, early menopause, smoking, alcohol consumption, and physical activity), the increased risk of MS after RPL remained significant (adjusted odds ratio, 1.10; 95% confidence interval, 1.06-1.15). Furthermore, in the analysis of the 5 diagnostic components of MS, a history of RPL significantly increased the risk of abdominal obesity, hypertriglyceridemia, low high-density lipoprotein cholesterol levels, and hyperglycemia.

CONCLUSION

Middle-aged women with a history of RPL have an increased risk of MS.

State-of-the-art-mini review: Dual pathway inhibition to reduce arterial and venous thromboembolism

Venous thromboembolism (VTE) and arterial thromboembolism (ATE) are linked by the common mechanism of thrombin generation. Historically these entities have been treated as separate pathophysiologic processes requiring different treatments: VTE, as the formation of fibrin-/coagulation-factor-derived thrombus in low flow vasculature, requiring anticoagulants; versus ATE, as largely platelet-derived thrombus in high flow vasculature, requiring antiplatelet agents. Observational studies have elucidated shared risk factors and co-morbidities predisposing individuals with VTE to ATE, and vice versa, and have bolstered the strategy of dual pathway inhibition (DPI) – the combination of low dose anticoagulants with antiplatelet agents – to reduce thrombotic outcomes on both sides of the vasculature. Randomized clinical trials have evaluated the efficacy and safety of such regimens - mostly rivaroxaban and aspirin - in high-risk groups of patients, including those with recent acute or chronic coronary syndrome, as well as those with peripheral artery disease with or without revascularization. Studies of extended VTE prophylaxis in acutely ill medical patients have also contributed to the evidence evaluating DPI. The totality of available data supports the concept that DPI can reduce major and fatal thromboembolic outcomes, including stroke, myocardial infarction, VTE, and cardiovascular death in key patient cohorts, with acceptable risk of bleeding. Further data are needed to refine which patients derive the best net clinical benefit from such an approach. At the same time, other novel agents such as contact pathway inhibitors that reduce thrombin generation without affecting hemostasis - and thus maximize safety - should be assessed in appropriate populations.

Risk Factors of Arterial Events in Patients with Venous Thromboembolism: A Systematic Review and Meta-Analysis

BACKGROUND

 If recent studies suggested that arterial ischemic events in patients with venous thromboembolism (VTE) are more frequent than in the general population without VTE, whether patients with VTE have different risk factors of arterial events than classic known cardiovascular risk factors remain undefined. Through this systematic review and meta-analysis, we aimed to identify risk factors of arterial ischemic events in patients with VTE.

METHODS

 We searched PubMed, EMBASE, and Cochrane databases to identify cohort studies published between January 1, 2000, and December 31, 2020, reporting risk factors of arterials ischemic events in patients with VTE. Random-effect models meta-analysis served to get the pooled hazard ratio (HR) and 95% confidence interval (CI) of each risk factor identified.

RESULTS

 We screened 1,467 records of which 18 were finally included in systematic review and 10 in meta-analyses. Adjusted HR for 9 factors were included in meta-analysis. Male gender (HR: 1.38; 95% CI: 1.28-1.49), diabetes (HR: 1.65; 95% CI: 1.28-2.12), hypertension (HR: 1.38; 95% CI: 1.04-1.84), previous atherothrombotic event (HR: 3.22; 95% CI: 1.12-9.23), chronic kidney disease (HR: 1.41; 95% CI: 1.05-1.88), cancer (HR: 1.72; 95% CI: 1.41-2.09), and unprovoked VTE (HR: 1.88; 95% CI: 1.37-2.57) were the identified risk factors of arterial events in VTE population after meta-analysis.

CONCLUSION

 Risk factors of arterial events in patients with VTE include usual cardiovascular risk factors and other risk factors that are related to VTE such as cancer and unprovoked VTE.

Metabolic Syndrome Increases Risk of Venous Thromboembolism Recurrence after Acute Pulmonary Embolism

Rationale: Metabolic syndrome (MetS), the clinical clustering of hypertension, dyslipidemia, insulin resistance, and abdominal obesity, has been associated with a prothrombotic and hypofibrinolytic state, although data linking MetS with venous thromboembolism (VTE) remain limited.Objectives: The aim of this study was to measure the prevalence of MetS in patients with pulmonary embolism (PE) across a large population and to examine its impact on VTE recurrence.Methods: This was a retrospective, population-based analysis using deidentified information from a large statewide database, the Indiana Network for Patient Care. All patients with an International Classification of Diseases-defined diagnosis of PE from 2004 to 2017 were included. We measured the frequency with which patients with PE carried a comorbid diagnosis of each MetS component. Multiple logistic regression analysis was performed with VTE recurrence as the dependent variable to test the independent effect of MetS diagnosis, with a statistical model using a directed acyclic graph to account for potential confounders and mediators. Kaplan-Meier curves were constructed to compare rates of VTE recurrence over time based on the presence or absence of MetS and its individual components.Results: A total of 72,936 patients were included in this analysis. The most common MetS component was hypertension with a prevalence of 59%, followed by hyperlipidemia (41%), diabetes mellitus (24%), and obesity (22%). Of these patients, 69% had at least one comorbid component of MetS. The overall incidence of VTE recurrence was 17%, increasing stepwise with each additional MetS component and ranging from 6% in patients with zero components to 37% in those with all four. Logistic regression analysis yielded an adjusted odds ratio of 3.03 (95% CI, 2.90-3.16) for the effect of composite diagnosis requiring at least three of the four components of MetS diagnosis on VTE recurrence.Conclusions: The presence of comorbid MetS in patients with PE is associated with significantly higher rates of VTE recurrence, supporting the importance of recognizing these risk factors and initiating appropriate therapies to reduce recurrence risk.

Frequency and incidence of arterial events in patients with venous thromboembolism compared to the general population: A systematic review and meta-analysis of cohort studies

BACKGROUND

Recent literature hypothesized that patients with venous thromboembolism (VTE) are at increased risk of developing arterial ischemic events than general population without VTE. However, data summarizing the epidemiology of arterial events among VTE population compared to the general population are lacking.

METHODS

We conducted a systematic review and meta-analysis from current literature. PubMed, EMBASE, and Cochrane databases were searched between Jan 1, 2000, and December 31, 2020. Eligible studies were observational cohort studies published in English on arterial ischemic events in patients with VTE. Pooled effect size estimates and their 95% confidence intervals were obtained through random-effect models meta-analysis.

RESULTS

Twenty-eight observational studies enrolling 352,014 patients were identified and included. The pooled frequency of all arterial events was 6.1% (95% CI: 3.7-9.1) in patients with VTE and was significantly higher than the pooled frequency of 5.0% (95% CI: 3.1-7.2) found in controls, with a pooled risk ratio (RR) of 1.20 (95% CI: 1.01-1.44; p = 0.0422). The pooled incidence of all arterial events in patients with VTE was 11.3‰ per patient-year (95% CI: 4.6-18.0), and was significantly higher than the 9.2‰ per patient-year (95% CI: 2.0-16.4) obtained in controls (Incidence rate ratio, IRR: 1.32; 95% CI: 1.08-1.61; p = 0.0103). The pooled frequency and pooled incidence of arterial events were also higher in patients with unprovoked VTE than in patients with provoked VTE (RR: 2.12; 95% CI: 1.38-3.24; p = 0.0042; and IRR: 2.26, 95% CI: 1.45-3.49; p = 0.0032).

CONCLUSION

The frequency and incidence of arterial events in patients with VTE are considerably higher than in the general population, without VTE. Further studies are urgently needed to understand these differences and reduce the burden related to these diseases.

FUNDING

None.

Metabolic syndrome increases risk of venous thromboembolism recurrence after acute deep vein thrombosis

An improved understanding of which patients are at higher risk of recurrent venous thromboembolism (VTE) is important to designing interventions to reduce degraded quality of life after VTE. Although metabolic syndrome (MetS), the clustering of hypertension, hyperlipidemia, diabetes mellitus, and obesity has been associated with a hypofibrinolytic state, data linking VTE recurrence with MetS remain limited. The purpose of this study was to measure the prevalence of MetS in patients with deep vein thrombosis (DVT) across a large population and determine its effect on VTE recurrence. This was a retrospective analysis of a large statewide database from 2004 to 2017. We measured the frequency with which patients with DVT carried a comorbid International Coding of Diseases diagnosis of MetS components. Association of MetS with VTE recurrence was tested with a multiple logistic regression model and VTE recurrence as the dependent variable. Risk of VTE recurrence conferred by each MetS component was assessed by Kaplan-Meier curves with the log-rank statistic. A total of 151 054 patients with DVT were included in this analysis. Recurrence of VTE occurred in 17% overall and increased stepwise with each criterion for MetS. All 4 components of MetS had significant adjusted odds ratios (OR) for VTE recurrence, with hyperlipidemia having the largest (OR, 1.8), representing the 4 largest ORs of all possible explanatory variables. All 4 MetS variables were significant on Kaplan-Meier analysis for recurrence of VTE. These data imply a role for appropriate therapies to reduce the effects of MetS as a way to reduce risk of VTE recurrence.

Rho GTPase regulation of reactive oxygen species generation and signalling in platelet function and disease

Platelets are master regulators and effectors of haemostasis with increasingly recognized functions as mediators of inflammation and immune responses. The Rho family of GTPase members Rac1, Cdc42 and RhoA are known to be major components of the intracellular signalling network critical to platelet shape change and morphological dynamics, thus playing a major role in platelet spreading, secretion and thrombus formation. Initially linked to the regulation of actomyosin contraction and lamellipodia formation, recent reports have uncovered non-canonical functions of platelet RhoGTPases in the regulation of reactive oxygen species (ROS), where intrinsically generated ROS modulate platelet function and contribute to thrombus formation. Platelet RhoGTPases orchestrate oxidative processes and cytoskeletal rearrangement in an interconnected manner to regulate intracellular signalling networks underlying platelet activity and thrombus formation. Herein we review our current knowledge of the regulation of platelet ROS generation by RhoGTPases and their relationship with platelet cytoskeletal reorganization, activation and function.

Venous Thromboembolism and Its Risk Factors in Children with Acute Lymphoblastic Leukemia in Israel: A Population-Based Study

Venous thromboembolism (VTE) is a serious complication of acute lymphoblastic leukemia (ALL) therapy. The aim of this population-based study was to evaluate the rate, risk factors, and long-term sequelae of VTE in children treated for ALL. The cohort included 1191 children aged 1-19 years diagnosed with ALL between 2003-2018, prospectively enrolled in two consecutive protocols: ALL-IC BFM 2002 and AIEOP-BFM ALL 2009. VTEs occurred in 89 patients (7.5%). Long-term sequelae were uncommon. By univariate analysis, we identified four significant risk factors for VTEs: Severe hypertriglyceridemia (p = 0.005), inherited thrombophilia (p < 0.001), age >10 years (p = 0.015), and high-risk ALL group (p = 0.039). In addition, the incidence of VTE was significantly higher in patients enrolled in AIEOP-BFM ALL 2009 than in those enrolled in ALL-IC BFM 2002 (p = 0.001). Severe VTE occurred in 24 children (2%), all of whom had at least one risk factor. Elevated triglyceride levels at diagnosis did not predict hypertriglyceridemia during therapy. In a multivariate analysis of 388 children, severe hypertriglyceridemia and inherited thrombophilia were independent risk factors for VTE. Routine evaluation for these risk factors in children treated for ALL may help identify candidates for intervention.

Changes in Childhood Body-Mass Index and Risk of Venous Thromboembolism in Adulthood

Background Childhood weight trajectories may influence cardiometabolic traits and thereby the risk of venous thromboembolism ( VTE ) later in life. We examined whether overweight and changes in weight status during childhood were associated with risk of VTE in adulthood. Methods and Results We used Danish medical registries to conduct a population-based cohort study of Danish schoolchildren aged 7 to 13 years and born during 1930-1989. We calculated body-mass index ( BMI ) z-scores based on weight and height measurements. We estimated hazard ratios using Cox regressions to examine associations between changes in BMI z-scores from 7 to 13 years of age and the subsequent risk of VTE . Among 313 998 children, 5007 girls and 5397 boys were diagnosed with VTE as adults. Compared with children with a normal BMI (25th to 75th percentile category) at both ages, children with a BMI persistently above the 75th percentile had a 1.30- to 1.50-fold increased risk of VTE in adulthood. Children who experienced a BMI increase from the 25th to 75th or >75th to 90th percentile to a higher percentile category had a 1.35- to 1.70-fold increased risk of adulthood VTE . Children whose BMI percentile category decreased between 7 and 13 years of age had a VTE risk similar to that of children with a persistently normal BMI . Conclusions Risk of VTE in adulthood was higher in children with a persistently above-average BMI . Whereas weight gain from 7 to 13 years of age additionally increased VTE risk, remission from overweight by 13 years of age completely reverted the risk.

Relationship between body mass index, risk of venous thromboembolism and pulmonary embolism: A systematic review and dose-response meta-analysis of cohort studies among four million participants

BACKGROUND

The relationship between body mass index (BMI) and risk of venous thromboembolism (VTE) and pulmonary embolism (PE) is a controversial issue. This dose-response meta-analysis was performed to investigate the association between BMI and risk of VTE and PE incidence based on cohort studies.

METHOD

A comprehensive systematic search was conducted up to August 2019 in MEDLINE/PubMed, SCOPUS, and Cochrane. DerSimonian and Laird random-effects models were run to estimate combined hazard ratios (HRs) with 95% confidence intervals (CIs). Dose-response analysis was also carried out based on BMI values.

RESULTS

Eleven articles with 16 arms and 3,910,747 participants were eligible for inclusion in this systematic review and meta-analysis. Pooled results showed a positive association between BMI and risk of VTE in the obese participants compared to participants classified in the normal BMI category (HR: 1.62, 95% CI: 1.29-2.04, I² = 95%). Furthermore, results showed a significant association between lower BMI (underweight versus normal BMI category) and reduced risk of PE (HR: 0.80, 95% CI: 0.70-0.92, I² = 9%) and higher risk of PE in obese versus normal BMI participants (HR: 2.24, 95% CI: 1.93-2.60, I² = 0%). There was a significant linear relationship between BMI and risk of VTE (p < 0.001) and PE (p < 0.001).

CONCLUSIONS

This systematic review and dose-response meta-analysis with 3,910,747 participants highlights obesity as a significant risk factor related to the incidence of VTE and PE.

Arterial and venous thrombosis: What's the link? A narrative review

Arterial thrombosis and venous thromboembolism (VTE) are traditionally considered two different entities. However, patients with unprovoked VTE are at higher risk of developing subclinical and overt atherosclerosis compared to healthy controls challenging these distinctions. Obesity may explain the association between arterial and venous disease: overweight/obese patients are prone to stasis in lower limbs veins, chronic inflammation, dyslipidemia, hypertension, and diabetes mellitus; all of which result in a hypercoagulability, VTE, and atherosclerosis. Novel therapeutic approaches combining and re-purposing traditional arterial therapies (antiplatelets and statins) and venous thrombosis therapies (anticoagulants) are emerging for the management of patients with vascular disease.

Reactive Oxygen Species in Venous Thrombosis

Reactive oxygen species (ROS) have physiological roles as second messengers, but can also exert detrimental modifications on DNA, proteins and lipids if resulting from enhanced generation or reduced antioxidant defense (oxidative stress). Venous thrombus (DVT) formation and resolution are influenced by ROS through modulation of the coagulation, fibrinolysis, proteolysis and the complement system, as well as the regulation of effector cells such as platelets, endothelial cells, erythrocytes, neutrophils, mast cells, monocytes and fibroblasts. Many conditions that carry an elevated risk of venous thrombosis, such as the Antiphospholipid Syndrome, have alterations in their redox homeostasis. Dietary and pharmacological antioxidants can modulate several important processes involved in DVT formation, but their overall effect is unknown and there are no recommendations regarding their use. The development of novel antioxidant treatments that aim to abrogate the formation of DVT or promote its resolution will depend on the identification of targets that enable ROS modulation confined to their site of interest in order to prevent off-target effects on physiological redox mechanisms. Subgroups of patients with increased systemic oxidative stress might benefit from unspecific antioxidant treatment, but more clinical studies are needed to bring clarity to this issue.

Venous thromboembolism prophylaxis using the Caprini score

Venous thromboembolism (VTE) including pulmonary embolism (PE) and deep vein thrombosis (DVT) is one of the leading causes of preventable cardiovascular disease in the United States (US) and is the number one preventable cause of death following a surgical procedure. Post-operative VTE is associated with multiple short and long-term complications. We will focus on reviewing the many faces of VTE in detail as they represent common challenging scenarios in clinical practice.

Increased risk of venous thromboembolism in hospitalized patients with cirrhosis due to non-alcoholic steatohepatitis

Objective

Patients with cirrhosis are at increased risk for venous thromboembolism (VTE) and portal vein thrombosis (PVT). Cirrhosis due to non-alcoholic steatohepatitis (NASH) appears to be particularly prothrombotic. We investigated hospitalized patients with NASH cirrhosis to determine if they are at increased risk for VTE.

Methods

Data on adult hospitalized patients with cirrhosis and VTE (deep vein thrombosis and/or pulmonary embolism) between November 1, 2010 and December 31, 2015 were obtained. Cases with VTE were matched by age, gender, and model for end stage liver disease (MELD) score to corresponding controls without VTE.

Results

Two hundred and ninety subjects (145 matched pairs) with mean age of 58.4 ± 11.8 years and MELD score of 16.0 ± 7.2 were included. Baseline characteristics were similar between cases and controls. Independent adjusted risk factors for VTE included NASH (OR: 2.46, 95% CI: 1.07–5.65, p = 0.034), prior VTE (OR: 7.12, 95% CI: 1.99–25.5, p = 0.003), and presence of PVT (OR: 2.18, 95% CI: 1.03–4.58, p = 0.041). Thrombocytopenia was associated with decreased risk (OR: 0.49, 95% CI: 0.26–0.95, p = 0.035).

Conclusions

NASH is an independent risk factor for VTE among cirrhosis patients and provides further evidence that NASH is a hypercoagulable state. While all hospitalized patients with cirrhosis at risk for VTE should be considered for medical thromboprophylaxis, those with NASH cirrhosis are at particularly increased risk and therefore a high index of suspicion for VTE should be maintained even in the presence of thromboprophylaxis.

Thrombosis in central obesity and metabolic syndrome: Mechanisms and epidemiology

Central obesity is a key feature of the metabolic syndrome (metS), a multiplex risk factor for subsequent development of type 2 diabetes and cardiovascular disease. Many metabolic alterations closely related to this condition exert effects on platelets and vascular cells. A procoagulant and hypofibrinolytic state has been identified, mainly underlain by inflammation, oxidative stress, dyslipidaemia, and ectopic fat that accompany central obesity. In support of these data, central obesity independently predisposes not only to atherothrombosis but also to venous thrombosis.

Increased risk and severity of unprovoked venous thromboembolism with clustering cardiovascular risk factors for atherosclerosis: Results of the REMOTEV registry

BACKGROUND

The role of cardiovascular risk factors (CVRF) for atherosclerosis in venous thromboembolic disease (VTE) is controversial. The aim of this study was to evaluate the impact of CVRF and their cumulative effects on the occurrence of unprovoked VTE, severity, recurrence and survival.

METHODS AND RESULTS

This is a prospective cohort from the REMOTEV registry including all consecutively hospitalized patients for acute symptomatic VTE. From November 2013 to December 2016, 515 patients with 6months follow-up (FU) were selected for the analysis. Events were classified as unprovoked or provoked VTE. In univariate analysis, hypertension (OR 1.44, [95% CI 1.01-2.06]), diabetes (OR 2.07, [95% CI: 1.25-3.55]) and age (OR 1.94, [95% CI: 1.31-2.88]) were significantly associated with the risk of unprovoked VTE. After adjustment, diabetes (OR 1.82, [95% CI: 1.07-3.18]) and age (OR 1.79, [95% CI: 1.15-2.8]) remained associated with the risk of unprovoked VTE. The proportion of unprovoked VTE increased significantly with the number of CVRF adjusted for thrombophilia (1 CVRF: OR 3 [95% CI: 1.44-6.52]) 2 CVRF: OR 4.33 [95% CI: 2.07-9.49] and ≥3 CVRF: OR 4.58 [95% CI: 2.27-9.7]). The severity of pulmonary embolism was significantly associated with CVRF clustering. There were more VTE recurrences and deaths during the 6months of FU with cumulative CVRF.

CONCLUSION

The risks of unprovoked VTE and PE severity are associated with clustering CVRF. The role of cumulative CVRF predominates rather than the specific burden of each of the CVRF in the risk of VTE occurrence.

Epidemiology and pathophysiology of venous thromboembolism: similarities with atherothrombosis and the role of inflammation

Venous thromboembolism (VTE) is a multifactorial disease. Major provoking factors (e. g. surgery, cancer, major trauma, and immobilisation) are identified in 50–60 % of patients, while the remaining cases are classified as unprovoked. However, minor predisposing conditions may be detectable in these patients, possibly concurring to the pathophysiology of the disease, especially when co-existing. In recent years, the role of chronic inflammatory disorders, infectious diseases and traditional cardiovascular risk factors has been extensively investigated. Inflammation, with its underlying prothrombotic state, could be the potential link between these risk factors, as well as the explanation for the reported association between arterial and venous thromboembolic events.

The potential role of endothelial dysfunction and platelet activation in the development of thrombotic risk in COPD patients

INTRODUCTION

Despite lack of knowledge in the field, several studies have underlined the role of endothelium dysfunction and platelet activation as significant players in the development and progression of chronic obstructive pulmonary disease (COPD). Indeed, endothelium plays a crucial role in vascular homeostasis and impairment, due to the inflammation process enhanced by smoking. Chronic inflammation and endothelial dysfunction have been proved to drive platelet activity. Consequently, thrombotic risk is enhanced in COPD, and might explain the higher percentage of cardiovascular death in such patients. Areas covered: This review aims to clarify the role of endothelium function and platelet hyper-activity as the pathophysiological mechanisms of the increased thrombotic risk in COPD. Expert commentary: In COPD patients, chronic inflammation does not impact only on lung parenchyma, but potentially involves all systems, including the endothelium of blood vessels. Impaired endothelium has several consequences, such as reduced vasodilatation capacity, enhanced blood coagulation, and increased platelet activation resulting in higher risk of thrombosis in COPD patients. Endothelium dysfunction and platelet activation are potential targets of therapy in patients with COPD aiming to reduce their risk of cardiovascular events.

Role of routine pre-operative screening venous duplex ultrasound in morbidly obese patients undergoing bariatric surgery

BACKGROUND/AIMS

It is well established that obesity is a strongly associated risk factor for post-operative deep vein thrombosis (DVT). Physical effects and pro-thrombotic, pro-inflammatory and hypofibrinolytic effects of severe obesity may predispose to idiopathic DVT (pre-operatively) because of which bariatric patients are routinely screened before surgery. The aim of this study was to audit the use of routine screening venous duplex ultrasound in morbidly obese patients before undergoing bariatric surgery.

METHODS

We retrospectively reviewed 180 patients who underwent bariatric surgery from August 2013 to August 2014 who had undergone pre-operative screening bilateral lower-extremity venous duplex ultrasound for DVT. Data were collected on patient's demographics, history of venous thromboembolism, prior surgeries and duplex ultrasound details of the status of the deep veins and superficial veins of the lower limbs.

RESULTS

No patients had symptoms or signs of DVT pre-operatively. No patient gave history of DVT. No patient was found to have iliac, femoral or popliteal vein thrombosis. Superficial venous disease was found in 17 (8%). One patient had a right lower limb venous ulcer.

CONCLUSION

Thromboembolic problems in the morbidly obese before bariatric surgery are infrequent, and screening venous duplex ultrasound can be done in high-risk patients only.

Persistent neutrophilia is a marker for an increased risk of venous thrombosis

In patients with cancer and myeloproliferative disorders, leukocytosis has been associated with an increased venous thromboembolic (VTE) risk. Our goal was to determine whether persistent neutrophilia (PN), not associated with known causes such as malignancies, infections or steroids, is independently associated with VTE. All adult patients with >3 outpatient complete blood counts (CBCs) within 3 years were included. PN was defined as having an absolute neutrophil count >95 % (>2SD) of the population (≥7.8 × 10(9)/L) on at least three CBCs, at least 2 months apart. Separate analyses for neutrophil counts ≥9 × 10(9)/L and ≥10 × 10(9)/L were also performed. Blood counts from inpatients were excluded. Primary outcome was diagnosis of VTE, as determined by ICD-9 codes. Odds ratios were adjusted for diabetes, smoking, obesity, gender, and age. Charlson score was utilized as a morbidity measure. Data on 43,538 outpatients were collected. Although there was no association of VTE with neutrophil counts ≥7.8 × 10(9)/L, patients with ≥9.0 × 10(9)/L neutrophils were twice as likely to be diagnosed with VTE compared to those with normal neutrophil counts (OR 2.0, 95 % CI 1.3, 3.1; p = 0.003). Patients with neutrophil counts ≥10.0 × 10(9)/L were at an even higher risk (OR 2.3, 95 % CI 1.2, 4.8; p = 0.019). Charlson scores significantly modified this risk when incorporated into analysis. Elevated neutrophil counts are associated with an increased risk of venous thrombosis even when they are not due to cancer, infection or steroids. In patients with significant comorbidities, neutrophilia may be a marker of VTE risk.

Venous thromboembolism has the same risk factors as atherosclerosis: A PRISMA-compliant systemic review and meta-analysis

BACKGROUND

Previous studies have shown that idiopathic pulmonary embolism is positively associated with other cardiovascular events, such as myocardial infarction and stroke, suggesting a potentially important association between atherosclerosis risk factors and venous thromboembolism (VTE). We performed a meta-analysis to evaluate the correlation between risk factors for atherosclerosis and VTE.

METHODS

In December 2014, we searched MEDLINE and EMBASE for studies evaluating the associations between VTE and risk factors for atherosclerosis and pooled outcome data using random-effects meta-analysis. In addition, we analyzed publication bias.

RESULTS

Thirty-three case-control and cohort studies with a total of 185,124 patients met the inclusion criteria. We found that participants with body mass index (BMI) ≥30 kg/m had a significantly higher prevalence of VTE than those with BMI <30 kg/m in both case-control studies (odds ratio [OR] = 2.45, 95% confidence interval [CI]: 1.78-3.35) and cohort studies (relative risk [RR] = 2.39, 95% CI: 1.79-3.17). VTE was more prevalent in patients with hypertension than without hypertension (OR = 1.40, 95% CI: 1.06-1.84; RR = 1.36, 95% CI: 1.11-1.67). The findings were similar for VTE prevalence between patients with and without diabetes (OR = 1.78, 95% CI: 1.17-2.69; RR = 1.41, 95% CI: 1.20-1.66). Current smoking was significantly associated with VTE prevalence in case-control studies (OR = 1.34, 95% CI: 1.01-1.77), but not in cohort studies (RR = 1.29, 95% CI: 0.96-1.72). In addition, we found that total cholesterol and triglyceride concentrations were significantly higher in patients with VTE than without VTE (weighted mean differences [WMD] = 8.94 mg/dL, 95% CI: 3.52-14.35 mg/dL, and WMD = 14.00 mg/dL, 95% CI: 8.85-19.16 mg/dL, respectively). High-density lipoprotein cholesterol concentrations were significantly lower in patients with VTE than without VTE (WMD = -2.03 mg/dL, 95% CI: -3.42 to -0.63 mg/dL). Higher quality studies were more homogeneous, but confirmed the same significant associations.

CONCLUSIONS

Based on our systematic review and meta-analysis, we observed a significant association between VTE and the risk factors for atherosclerosis. These results may make an important contribution to clinical practice regarding VTE treatment.

Clinical Features and Developing Risks of Saphenous Vein Thrombophlebitis

We evaluated the clinical features and the risks of 14 patients with 14 limbs affected by saphenous vein thrombophlebitis from April 2007 to May 2013 and compared the results with patients undergoing operative repair of varicose veins (127 patients, 193 limbs) during the study period. The frequency of patients with a body mass index over 25 (78.6% vs. 35.3%, p = 0.0018), varicose change in the saphenous vein (78.6% vs. 6.2%, p <0.0001), and concurrent thrombosis in another vein (50.0% vs. 7.1%, p <0.0001) were all significantly higher than those of the patients under operative repair for varicose veins. These patients with clinical features above may be at an elevated risk of thrombophlebitis of the saphenous trunk. (This article is a translation of J Jpn Coll Angiol 2014; 54: 151-157).

Case report: Limb-threatening femoral vein thrombosis in a healthy carpet fitter: Carpet fitter’s thrombosis

Objective

To report a case of femoral vein thrombosis in a carpet fitter and to highlight this as an occupational hazard.

Method

Case presentation and literature review.

Results

An otherwise fit 21-year-old carpet fitter with no past medical history presented with acute thrombosis of his left common femoral, superficial femoral and great saphenous veins. Attempted catheter directed thrombolysis was unsuccessful. Due to severe pain and the threat of venous gangrene he was treated by emergency surgical thrombectomy with excision of chronic venous scarring and vein-patch repair that led to resolution of his symptoms.

Conclusions

Deep vein thrombosis is typically associated with factors such as increasing age and prolonged periods of immobility; however, certain ‘active’ occupations can increase its risk. Crouched and cramped working conditions including repetitive active movement with flexed hips and knees can predispose to increased risk of venous thromboembolism.

Decrease in microvesicle-associated tissue factor activity in morbidly obese patients after bariatric surgery

BACKGROUND

Tissue factor (TF) is the main in vivo initiator of the blood coagulation cascade. Active circulating TF was detected on small, negatively charged membrane vesicles, the so-called microvesicles (MVs), which are released upon cell activation and apoptosis from a variety of cells. Increased coagulation activation was found in morbidly obese patients, and elevated levels of TF-bearing MVs may contribute to the prothrombotic state in these patients.

AIM

To determine MV-associated TF activity levels in morbidly obese patients before and after weight loss due to bariatric surgery.

METHODS

MV-TF activity was measured with a factor Xa generation assay in morbidly obese patients before and 2 years after bariatric surgery. In addition, clinical parameters were determined.

RESULTS

Seventy-four morbidly obese patients (mean age: 42 (±11) years; 61 females) were included in this study. After bariatric surgery, the body mass index decreased from (median, 25-75th percentile) 45.5 (42.3-50.2) to 30.5 (28.0-34.4 kg m(-2); P<0.001), and a significant improvement in metabolic parameters was observed. Preoperative MV-TF activity correlated with C-reactive protein levels (r=0.3; P=0.02). Postoperatively, the mean MV-TF activity decreased significantly from 0.20 pg ml(-1) (0.18-0.47) to 0.02 (0.00-0.28; P<0.01).

CONCLUSION

We could demonstrate a significant decrease in MV-TF activity after weight loss in morbidly obese patients. Decreased MV-TF activity might contribute to an improved coagulation profile in these patients after weight loss.

Relation between preclinical atherosclerosis and venous thromboembolism in patients with thrombophilias - longitudinal study

Preclinical atherosclerosis may represent a risk factor for venous thromboembolism (VTE). In longitudinal study we followed longitudinally 96 patients (32 men) with thrombophilias with (n=51) and without (n=45) history of VTE. In both groups we studied the changes of preclinical atherosclerosis at peripherally located arteries detected by ultrasound. In addition, we assessed changes in selected risk factors of atherosclerosis. During the mean follow-up of 56.0+/-7.62 months we did not find significant change in preclinical atherosclerosis defined as Belcaro score in either group (-3 % in the VTE group vs 0 % in non VTE group). Significant increase in body mass index (1.03+/-1.98 kg*m(-2), resp. 1.21+/-1.67 kg*m(-2), p<0.01) and non-significant increase in systolic blood pressure were detected in both groups. Waist circumference increased significantly only in patients without VTE (4.11+/-7.84 cm, p<0.05). No differences in changes of risk factors under study between both groups were detected. In summary, patients with thrombophilia and history of VTE showed no evidence of greater progression of atherosclerosis or increase in traditional risk factors of atherosclerosis than patients with thrombophilia without history of VTE. Unfavorable changes of body mass index, waist circumference and systolic blood pressure were detected in both groups during study period.

Association between the metabolic syndrome, its individual components, and unprovoked venous thromboembolism: results of a patient-level meta-analysis

OBJECTIVE

The metabolic syndrome (MetS) may contribute to the pathogenesis of venous thromboembolism (VTE), but this association requires additional investigation.

APPROACH AND RESULTS

We performed a patient-level meta-analysis of case-control and cohort studies that evaluated the role of MetS and risk of unprovoked VTE. For case-control studies, odds ratios and 95% confidence intervals were calculated using logistic regression analysis to estimate the influence of individual variables on the risk of VTE; χ(2) tests for trend were used to investigate the effect of increasing number of components of MetS on the risk of VTE and to explore the influence of abdominal obesity on this relationship. For cohort studies, hazard ratios and 95% confidence interval were calculated using multivariable Cox regression analysis. Six case-control studies were included (908 cases with unprovoked VTE and 1794 controls): in multivariate analysis, MetS was independently associated with VTE (odds ratio, 1.91; 95% confidence interval, 1.57-2.33), and both MetS and abdominal obesity were better predictors of unprovoked VTE than obesity defined by the body mass index. Two prospective cohort studies were included (26,531 subjects and 289 unprovoked VTE events): age, obesity, and abdominal obesity, but not MetS were associated with VTE.

CONCLUSIONS

Case-control but not prospective cohort studies support an association between MetS and VTE. Abdominal adiposity is a strong risk factor for VTE.

Atrial fibrillation associated with increased risk of venous thromboembolism. A population-based cohort study

Whether atrial fibrillation (AF) is associated with an increased risk of venous thromboembolism (VTE) remains controversial. From Longitudinal Health Insurance Database 2000 (LHID2000), we identified 11,458 patients newly diagnosed with AF. The comparison group comprised 45,637 patients without AF. Both cohorts were followed up to measure the incidence of deep-vein thrombosis (DVT) and pulmonary embolism (PE). Univariable and multivariable competing-risks regression model and Kaplan-Meier analyses with the use of Aelon-Johansen estimator were used to measure the differences of cumulative incidences of DVT and PE, respectively. The overall incidence rates (per 1,000 person-years) of DVT and PE between the AF group and non-AF groups were 2.69 vs 1.12 (crude hazard ratio [HR]= 1.92; 95 % confidence interval [CI] = 1.54-2.39), 1.55 vs 0.46 (crude HR = 2.68; 95 % CI = 1.97-3.64), respectively. The baseline demographics indicated that the members of the AF group demonstrated a significantly older age and higher proportions of comorbidities than non-AF group. After adjusting for age, sex, and comorbidities, the risks of DVT and PE remained significantly elevated in the AF group compared with the non-AF group (adjusted HR = 1.74; 95 %CI = 1.36-2.24, adjusted HR = 2.18; 95 %CI = 1.51-3.15, respectively). The Kaplan-Meier curve with the use of Aelon-Johansen estimator indicated that the cumulative incidences of DVT and PE were both more significantly elevated in the AF group than in the non-AF group after a long-term follow-up period (p<0.01). In conclusion, the presence of AF is associated with increased risk of VTE after a long-term follow-up period.

Changes in lipid metabolism and extension of venous thromboembolism

BACKGROUND/AIMS

Deep vein thrombosis (DVT) and pulmonary embolism (PE) are common diseases with a vast number of acquired and congenital risk factors. Disorders of the lipid metabolism are not established risk factors for venous thromboembolism (VTE) so far. However, in recent literature, associations between VTE and the metabolic syndrome, especially with elevated lipid parameters, have been described. The aim of our study was to investigate the association between the extension of VTE and changes in the lipid profile.

METHODS

We included 178 VTE patients in our study; 59 patients had isolated PE, 39 patients had isolated DVT of the leg and 80 patients had both (DVT and PE). Concerning PE, we distinguished between massive and submassive PE. We evaluated plasma lipids and lipoproteins in PE and DVT patients as well as in massive and submassive PE patients.

RESULTS

PE patients had higher levels of plasma triglycerides [median (interquartile range): 162 (109-254) vs. 136.5 (96.5-162) mg/dl, p = 0.047] and lower levels of high-density lipoprotein cholesterol (HDL-C; 52.1 ± 17.2 vs. 63.9 ± 22.7 mg/dl, p = 0.004) than DVT patients. Furthermore, PE patients were significantly older than DVT patients (59.6 ± 16.9 vs. 52.2 ± 15.5 years, p = 0.02). We were not able to find differences in lipid parameters in patients with massive PE compared to those with submassive PE. However, patients with massive PE were more obese than patients with submassive PE (body mass index 29.1 ± 4.6 vs. 26.9 ± 4.9, p = 0.012).

CONCLUSIONS

Lipid parameters and lipoproteins differ between DVT and PE patients. PE patients had higher triglyceride and lower HDL-C levels compared with DVT patients.

P-selectin: an unpredicted factor for deep vein thrombosis after total hip arthroplasty

INTRODUCTION

Deep vein thrombosis (DVT) is a severe complication after total hip arthroplasty (THA). It leads to acute pulmonary embolism, a life-threatening disease. P-selectin is a 140-kDa transmembrane glycoprotein. Elevated P-selectin was associated with 1.7-fold increase in the risk of venous thrombosis.

MATERIALS AND METHODS

To confirm the association, a total of 91 subjects who received primary total hip arthroplasty using lateral approach performed by one skilled orthopedic surgeon were studied. All the patients were consecutively enrolled at the Center of Diagnosis and Treatment for Joint Diseases, Drum Tower Hospital affiliated to the Medical School of Nanjing University from 2010 to 2012. All the subjects received venography 3-5 days after operation. We measured P-selectin by means of a highly sensitive sandwich ELISA technique and a commercially available test reagent set.

RESULTS

No significant association was detected between P-selectin and DVT (all P values > 0.05). ΔsP-selectin was correlated with weight, APTT after operation, history of DVT, and diagnosis of primary disease ( P values were 0.03, 0.03, 0.04, and 0.02, resp.).

CONCLUSION

P-selectin may not be a predicted factor for deep vein thrombosis after total hip arthroplasty.

Glycemia (hemoglobin A1c) and incident venous thromboembolism in the Atherosclerosis Risk in Communities cohort study

Diabetes has been inconsistently associated with increased risk of venous thromboembolism (VTE) and there is little direct evidence on the associations of glycemia levels with VTE. We used data from the Atherosclerosis Risk in Communities study to test the hypothesis that glycemia, as measured by hemoglobin A1c (A1c), is positively associated with VTE. Participants aged 45-64 years (n = 12,298) had A1c measured in 1990 and were followed for incident VTE (n = 345) through 2005. Because A1c is affected by diabetes treatment, analyses were stratified by history of diagnosed diabetes. Owing to evidence of non-linearity, we categorized A1c according to clinical cut-points: <5.7, 5.7-6.4, and ≥ 6.5% in those with no diagnosed diabetes; <7.0 and ≥ 7.0% in those with diagnosed diabetes. After adjustment for potential confounders, the hazard ratios (95% CIs) for VTE across increasing A1c categories were 1 (referent), 1.02 (0.77, 1.35) and 0.72 (0.41, 1.29) for those without diagnosed diabetes, and 1.30 (0.77, 2.17) and 1.41 (0.95, 2.09) for those with diagnosed diabetes. To explore the relation, we employed various models to adjust for potential confounding variables and modeled A1c as tertiles. We consistently found elevated hazard ratios in those with diagnosed diabetes, though the association was not statistically significant in every model. Hazard ratios in those without diagnosed diabetes were close to 1. In conclusion, our results are mildly suggestive that diagnosed diabetes and high levels of glucose, per se, may increase the risk of VTE. Elevated glucose was not related to VTE in those without diagnosed diabetes.

Risk Factors for Venous Thromboembolism in Chronic Obstructive Pulmonary Disease

BACKGROUND

COPD patients are at increased risk for venous thromboembolism (VTE). VTE however remains under-diagnosed in this population and the clinical profile of VTE in COPD is unclear.

METHODS

Global initiative for chronic Obstructive Lung Disease (GOLD) stages II-IV participants in the COPD Genetic Epidemiology (COPDGene) study were divided into 2 groups: VTE+, those who reported a history of VTE by questionnaire, and VTE-, those who did not. We compared variables in these 2 groups with either t-test or chi-squared test for continuous and categorical variables, respectively. We performed a univariate logistic regression for VTE, and then a multivariate logistic regression using the significant predictors of interest in the univariate analysis to ascertain the determinants of VTE.

RESULTS

The VTE+ group was older, more likely to be Caucasian, had a higher body mass index (BMI), smoking history, used oxygen, had a lower 6-minute walk distance, worse quality of life scores, and more dyspnea and respiratory exacerbations than the VTE- group. Lung function was not different between groups. A greater percentage of the VTE+ group described multiple medical comorbidities. On multivariate analysis, BMI, 6-minute walk distance, pneumothorax, peripheral vascular disease, and congestive heart failure significantly increased the odds for VTE by history.

CONCLUSIONS

BMI, exercise capacity, and medical comorbidities were significantly associated with VTE in moderate to severe COPD. Clinicians should suspect VTE in patients who present with dyspnea and should consider possibilities other than infection as causes of COPD exacerbation.

Risk Factors for Venous Thromboembolism in Chronic Obstructive Pulmonary Disease

BACKGROUND

COPD patients are at increased risk for venous thromboembolism (VTE). VTE however remains under-diagnosed in this population and the clinical profile of VTE in COPD is unclear.

METHODS

Global initiative for chronic Obstructive Lung Disease (GOLD) stages II-IV participants in the COPD Genetic Epidemiology (COPDGene) study were divided into 2 groups: VTE+, those who reported a history of VTE by questionnaire, and VTE-, those who did not. We compared variables in these 2 groups with either t-test or chi-squared test for continuous and categorical variables, respectively. We performed a univariate logistic regression for VTE, and then a multivariate logistic regression using the significant predictors of interest in the univariate analysis to ascertain the determinants of VTE.

RESULTS

The VTE+ group was older, more likely to be Caucasian, had a higher body mass index (BMI), smoking history, used oxygen, had a lower 6-minute walk distance, worse quality of life scores, and more dyspnea and respiratory exacerbations than the VTE- group. Lung function was not different between groups. A greater percentage of the VTE+ group described multiple medical comorbidities. On multivariate analysis, BMI, 6-minute walk distance, pneumothorax, peripheral vascular disease, and congestive heart failure significantly increased the odds for VTE by history.

CONCLUSIONS

BMI, exercise capacity, and medical comorbidities were significantly associated with VTE in moderate to severe COPD. Clinicians should suspect VTE in patients who present with dyspnea and should consider possibilities other than infection as causes of COPD exacerbation.

Individuals with coronary artery disease at a young age and features of the metabolic syndrome have an increased prothrombotic potential

The relation between coagulation and atherosclerosis has been extensively described, pointing towards a hypercoagulable state in patients with atherosclerosis, especially in young individuals. However, not all studies were conclusive. It is known that the metabolic syndrome (MetS), a risk factor for coronary artery disease (CAD), is related to a higher incidence of thrombo-embolic events. We hypothesised that individuals with CAD at a young age and MetS have an increased prothrombotic potential. It was the study objective to analyse the endogenous thrombin potential (ETP) and related thrombin generation parameters in patients with CAD before the age of 51 in men and 56 in women with and without MetS features and their healthy first-degree relatives. In this case-control study we included 118 CAD patients and 50 first-degree relatives (controls). Parameters of thrombin generation were obtained with calibrated automated thrombinography. An adjusted general linear model (GLM) showed a positive association between the peak thrombin levels and the presence of CAD at a young age. Based on the NCEP criteria we divided our patient group in CAD patients with and without MetS, and compared them to the controls without MetS. We showed that CAD patients with MetS have increased ETP levels, both in comparison with healthy first-degree relatives and with CAD patients without MetS. There were no differences in ETP between patients without MetS and healthy controls. In conclusion, this study shows that individuals with CAD at a young age and MetS features have an increased prothrombotic potential, compared to CAD patients without MetS.

Metabolic syndrome increases risk for pulmonary embolism after hip and knee arthroplasty

Aim

To investigate whether patients with metabolic syndrome (MetS) undergoing total hip or knee replacement have an increased risk for pulmonary embolism (PE).

Methods

We studied patients undergoing total hip or total knee replacement from January 2001 to April 2006. The diagnosis of PE was based on a positive finding with a chest CT or a lung scan. Components of MetS were defined as 1) BMI≥30 kg/m², 2) non-fasting preadmission glucose ≥11.1 mmol/L or diagnosis of diabetes, 3) hypertension, and 4) dyslipidemia. MetS was diagnosed if at least three of these components were present.

Results

Of 7282 patients, 107 (1.47%) were diagnosed with PE. The incidence of PE in patients with 0, 1, 2, 3, and 4 MetS components was respectively 0.85% (16/1888; 95% confidence interval [CI] 0.5%-1.4%), 1.24% (31/2500; 95% CI 0.9%-1.8%), 1.76% (34/1936; 95% CI 1.2%-2.5%), 2.64% (21/796; 95% CI 1.7%-4.1%), and 3.09% (5/162; 95% CI 1.1%-7.4%). The independent risk factors for PE were age ≥70, knee as opposite to hip replacement, bilateral knee surgery, congestive heart failure, and MetS or the number of MetS components. The odds of PE independently increased 1.6 times (95% CI 1.01-2.56; P = 0.043) for patients with MetS and 1.23 times (95% CI 1.02-1.48; P = 0.028) per each additional MetS component.

Conclusion

Patients with MetS are at increased risk for PE after total joint arthroplasty. The increasing number of MetS components significantly increased the incidence of PE.

Efficacy and safety outcomes of oral anticoagulants and antiplatelet drugs in the secondary prevention of venous thromboembolism: systematic review and network meta-analysis

OBJECTIVE

To summarise and compare the efficacy and safety of various oral anticoagulants (dabigatran, rivaroxaban, apixaban, and vitamin K antagonists) and antiplatelet agents (acetylsalicylic acid) for the secondary prevention of venous thromboembolism.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

Literature search using Medline (1950 to present), Embase (1980 to present), and the Cochrane Register of Controlled Trials using the OVID interface. Publications from potentially relevant journals were also searched by hand.

REVIEW METHODS

Randomised controlled trials of patients receiving anticoagulants, antiplatelet drugs, or placebo or observation for secondary prevention of venous thromboembolism. Selected outcomes were rates of recurrent venous thromboembolism and major bleeding. Two reviewers independently extracted data onto standardised forms.

RESULTS

12 articles met our inclusion criteria, with 11,999 patients evaluated for efficacy and 12,167 for safety. All treatments reduced the risk of recurrent venous thromboembolism. Compared with placebo or observation, vitamin K antagonists at a standard adjusted dose (target international normalised ratio 2.0-3.0) showed the highest risk difference (odds ratio 0.07; 95% credible interval 0.03 to 0.15) and acetylsalicylic acid showed the lowest risk difference (0.65; 0.39 to 1.03). Risk of major bleeding was higher with a standard adjusted dose of vitamin K antagonists (5.24; 1.78 to 18.25) than with placebo or observation. Fatal recurrent venous thromboembolism and fatal bleeding were rare. Detailed subgroup and individual patient level data were not available.

CONCLUSIONS

All oral anticoagulants and antiplatelet agents investigated in this analysis were associated with a reduced recurrence of venous thromboembolism compared with placebo or observation, although acetylsalicylic acid was associated with the lowest risk reduction. Vitamin K antagonists given at a standard adjusted dose was associated with the greatest risk reduction in recurrent venous thromboembolism, but also the greatest risk of major bleeding.

Patients with uncontrolled components of metabolic syndrome have increased risk of complications following total joint arthroplasty

Metabolic syndrome (MetS)-a diagnostic grouping of diabetes, dyslipidemia, hypertension, and obesity-has been indicated as a risk factor for perioperative complications following total joint arthroplasty (TJA). This study investigates the impact of MetS on perioperative complications, specifically the importance of controlling MetS components. One hundred thirty-three patients undergoing TJA with all four components of MetS were identified. They were matched one-to-one with patients without MetS. Control of diabetes, dyslipidemia, and hypertension was assessed. Thirty-five patients with MetS were found to have at least a single uncontrolled component. The complication rates were 49%, 8%, and 8% for uncontrolled MetS, controlled MetS, and no MetS, respectively. Multivariate analysis confirmed independent associations between control of MetS components and both perioperative complications and length of stay. Both surgeons and patients should be aware of the substantial risk of dangerous complications following TJA in patients with uncontrolled metabolic syndrome.

Low CD34+ cells, high neutrophils and the metabolic syndrome are associated with an increased risk of venous thromboembolism

The relationship between MetS (metabolic syndrome), levels of circulating progenitor/immune cells and the risk of VTE (venous thromboembolism) has not yet been investigated. We studied 240 patients with previous VTE and 240 controls. The presence of MetS was identified according to NCEP ATP III guidelines and flow cytometry was used to quantify circulating CD34+ cells. VTE patients showed higher BMI (body mass index), waist circumference, triacylglycerol (triglyceride) levels, blood glucose, hs-CRP (high-sensitivity C-reactive protein) and lower HDL-C (high-density lipoprotein cholesterol) levels. The prevalence of MetS was significantly higher in VTE (38.3%) than in control individuals (21.3%) with an adjusted OR (odds ratio) for VTE of 1.96 (P=0.002). VTE patients had higher circulating neutrophils (P<0.0001), while the CD34+ cell count was significantly lower among patients with unprovoked VTE compared with both provoked VTE (P=0.004) and controls (P=0.003). Subjects were also grouped according to the presence/absence of MetS (MetS+ or MetS−) and the level (high/low) of both CD34+ cells and neutrophils. Very high adjusted ORs for VTE were observed among neutrophils_high/MetS+ (OR, 3.58; P<0.0001) and CD34+_low/MetS+ (OR, 3.98; P<0.0001) subjects as compared with the neutrophils_low/MetS− and CD34+_high/MetS− groups respectively. In conclusion, low CD34+ blood cell count and high circulating neutrophils interplay with MetS in raising the risk for venous thromboembolic events.

A unique presentation of four thrombotic events at a time

A 72-year-old man was referred to our hospital as a case of postcardiac arrest following a long distance air flight. Work-up in the emergency department revealed the presence of deep vein thrombosis (DVT), bilateral pulmonary embolism, inferior STEMI (ST elevation myocardial infarction) and ischaemic stroke. He received thrombolysis by recombinant tissue plasminogen activator (tPA) following which his haemodynamic status improved, but he developed haemorrhagic transformation of the stroke as a complication. The haemorrhagic lesion gradually resolved with conservative management, leaving behind a residual neurological deficit. His haemodynamic status was stable after the management. Although a diagnosis of right-to-left shunt lesion was highly suggestive in this condition, it could not be confirmed on the transthoracic echocardiogram. Our patient had a unique presentation of multiple thrombi in different organs that caused significant morbidity and haemodynamic instability. There are no well-established guidelines that discuss the acute management of such cases. This situation requires a careful assessment and management of the patient by a multidisciplinary team.

Is polycystic ovary syndrome another risk factor for venous thromboembolism? United States, 2003-2008

OBJECTIVE

We sought to determine prevalence and likelihood of venous thromboembolism (VTE) among women with and without polycystic ovary syndrome (PCOS).

STUDY DESIGN

We performed a cross-sectional analysis using Thomson Reuters MarketScan Commercial databases for the years 2003 through 2008. The association between VTE and PCOS among women aged 18-45 years was assessed using age-stratified multivariable logistic regression models.

RESULTS

Prevalence of VTE per 100,000 was 374.2 for PCOS women and 193.8 for women without PCOS. Compared with women without PCOS, those with PCOS were more likely to have VTE (adjusted odds ratio [aOR] 18-24 years, 3.26; 95% confidence interval [CI], 2.61-4.08; aOR 25-34 years, 2.39; 95% CI, 2.12-2.70; aOR 35-45 years, 2.05; 95% CI, 1.84-2.38). A protective association (odds ratio, 0.8; 95% CI, 0.73-0.98) with oral contraceptive use was noted for PCOS women.

CONCLUSION

PCOS might be a predisposing condition for VTE, particularly among women aged 18-24 years. Oral contraceptive use might be protective.

Abdominal obesity and the risk of venous thromboembolism among women: a potential role of interleukin-6

BACKGROUND

Abdominal obesity increases the risk of venous thromboembolism (VTE). It remains unclear to what extent inflammation contributes to the risk of VTE from abdominal obesity. Our objectives were to investigate the association between abdominal obesity and VTE and the effect of inflammation on this association in a case-control study comprised of women.

METHODS

We included 84 patients with VTE (18-60 years of age) and 100 controls. Waist circumference (WC), interleukin-6 (IL-6), and high-sensitivity C-reactive protein (hsCRP) levels were determined at least 7 months after the thrombotic event.

RESULTS

A total of 51 patients (61%) and 43 (43%) controls had abdominal obesity (WC ≥88 cm). The odds ratios (OR) adjusted for age were 2.40 [95% confidence interval (CI) 1.06-5.41; P=0.035] for a WC ≥88 cm compared to a WC <80 cm; the association was attenuated after adjusting for IL-6 (OR 1.86, 95% CI 0.80-4.33; P=0.149). For every 10-cm increment in WC, the risk of VTE adjusted for age increased by 1.38 (95% CI 1.08-1.77; P=0.010). The effect of an increased WC on the risk of VTE was again attenuated when IL-6 was entered in the regression model (OR 1.24, 95% CI 0.95-1.61; P=0.109). Risk estimates did not substantially change with adjustment for hsCRP.

CONCLUSION

Our data indicate that the association between VTE and an increased WC was attenuated after adjustment for IL-6, suggesting a potential role of this interleukin in mediating the link between abdominal obesity and VTE.