Important Risk Factor For Venous Thromboembolism Research Articles

Venous Thromboembolism Risk Factors in Women With Obesity Who Undergo Cesarean Delivery.

Venous thromboembolism (VTE) is a leading cause of maternal mortality. Obesity and cesarean delivery are established risk factors for pregnancy-related VTE. We identified additional risk factors among patients with obesity who underwent a cesarean delivery to identify those who need VTE prophylaxis. We conducted a secondary analysis of data from the Maternal-Fetal Medicine Units Network (MFMU) Cesarean Registry Database using a case-control design. Cases were identified as women with obesity having a pre-pregnancy body mass index of >30 kg/m2, who underwent cesarean delivery and subsequently developed deep venous thrombosis (DVT) or pulmonary embolism (PE). These women were compared to a control group of women with obesity who underwent cesarean delivery but did not develop DVT or PE. Analysis of risk factors associated with VTE was performed using Chi-Square test and Fisher's exact test. We identified 43 VTE cases and 172 controls in the MFMU database. Increased risk of VTE was noted in women with endometritis (OR of 4.58 [95% CI: 1.86-11.2, P = .0004]), receiving a blood transfusion (OR 17.07 [95% CI: 4.46-65.3, P = .0001]), having a coagulopathy (OR 27.73 [95% CI: 3.24-237.25, P = .0003]), and urinary tract infection (OR 2.39 [95% CI: 1.08-5.28, P = .03]). Important risk factors for VTE in women with obesity who undergo cesarean delivery include endometritis, intra- or post-operative transfusion, coagulopathy, and urinary tract infection. The presence of one or more of these factors may help guide provider decision-making regarding whether to administer thromboprophylaxis.

Thromboprophylaxis in Urological and Andrological Surgery (Review article)

Last decades urologist started to performed big amount of complicated oncological operation with substantial risk of both venous thromboembolism (VTE) and bleeding. Prophylaxis of VTE remains a vital problem, as it is potentially fatal and is associated with significant morbidity. Prophylaxis of this complication is not clearly defined and is mainly based on information from other surgical specialties (like orthopedic or general surgery). Scientific publications dedicated VTE prophylaxis in field of urology were reported only in the last decade. Most studies showed that pharmacological prophylaxis decreases the relative risk of VTE in surgical patients by approximately 50%, but with an increase in the relative risk of postoperative major bleeding of 50%. Main models for evaluation of different VTE risk factors were analyzed. The most important risk factors for VTE are age of 75 or more, body mass index 35 or more, prior VTE or VTE in 1st degree relative. As for urological procedure, deep venous thrombosis rates of 0.2–7.8% and pulmonary embolism of 0.2–7% have been reported. It was shown that recommendations for VTE prophylaxis varies in different guidelines and their summary for most popular operations were described. Generally, most recommendations state that low-risk procedures need no prophylaxis or solely mechanical prophylaxis. Moderate-risk categories can either have mechanical or pharmacological prophylaxis. The high-risk category should have both mechanical and pharmacological prophylaxis, and extended prophylaxis should be considered. Despite massive evidences about risk of VTE among different types of surgical patients, real clinical practice doesn’t show the strict adherence to VTE prophylaxis recommendations.

Analysis of influencing factors of community-acquired pneumonia with deep venous thrombosis in elderly communities

Community-acquired pneumonia (CAP) is one of the common infectious diseases that threaten human health, venous thromboembolism (VTE), including deep venous thrombosis (DVT) and pulmonary thromboembolism (PTE), is a global health care problem. Acute infection and age ≥70 years are important risk factors for VTE in internal medicine inpatients. There is increasing evidence that acute infectious diseases caused by bacterial and viral infections can induce coagulation, platelet (PLT) activation and inhibit the activity of anticoagulant factors. However, there is no consensus on whether patients with CAP suffer from DVT. Finding out the clinical characteristics and risk factors of DVT in elderly patients with CAP is helpful for early identification of high-risk patients with VTE and timely prevention, which can significantly reduce the occurrence of VTE in hospitals. Data was collected from 505 patients with CAP aged ≥70 years old hospitalized in the Department of Respiratory and Critical Care Medicine. 133 patients with DVT were selected as the DVT group. DVT score and risk grading were performed for all patients using Padua. Fifty-seven cases were diagnosed as having severe pneumonia, including 50 cases diagnosed as having septic shock. Padua, D-dimer, between the DVT group and the control group, the severe pneumonia group and the non-severe pneumonia group, and the severe pneumonia DVT group and the control group were compared. (I) The incidence of DVT with severe pneumonia was much higher than with non-severe pneumonia (P<0.001). The incidence of DVT in patients with septic shock and non-septic shock was 74.0% (37/50) and 28.6% (2/7) respectively (P=0.0154). (II) There were significant differences in Padua scores between the DVT group and the control group and between the severe pneumonia group and non-severe pneumonia group (P<0.001). (III) There were significant differences in D-dimer level between the DVT group and the control group and between the severe pneumonia group and the non-severe pneumonia group (P<0.001). (IV) Regression analysis indicated the central venous catheter (CVC), D-dimer value, and Padua score were significantly correlated with thrombosis (P=0.042, <0.001, 0.043). Severe pneumonia in elderly patients and septic shock may be complicated by DVT, and central venous catheterization and D-dimer are closely related to thrombosis.

Evaluation of the impact of body mass index on venous thromboembolism risk factors.

In this paper, we investigate the interaction impacts of body mass index (BMI) on the other important risk factors for venous thromboembolism (VTE), using deep venous thrombosis (DVT) patient data from the International Warfarin Pharmacogenetics Consortium (IWPC). We apply eight machine learning techniques, including naive Bayes classifier (NB), support vector machine (SVM), elastic net regression (ENET), logistic regression (LR), lasso regression (LAR), multivariate adaptive regression splines (MARS), boosted regression tree (BRT) and random forest model (RF). The RF method is selected as the best model for classification. Out of 33 features considered in this study, we identify 12 variables as relatively important risk factors for VTE. Finally, we examine the interaction impacts of BMI on these important VTE risk factors. We conclude that the impacts of risk factors on VTE incidence are varying across different BMI groups, and the variations are different for different risk factors. Therefore the interaction impacts of BMI on the other risk factors have to be taken into account in order to better understand the incidence of VTE.

Risk prediction for cancer-associated thrombosis in ambulatory patients with cancer: past, present and future

Venous thromboembolism (VTE) is a preventable disease, thus, in a number of clinical situations primary thromboprophylaxis has been proposed. Although we now know that cancer is one of the most important risk factors for VTE, primary prophylactic anticoagulation is only widely established for high-risk hospitalized patients and peri- and postoperatively after major cancer surgery. Long-term primary thromboprophylaxis in ambulatory cancer patients has been demonstrated to be effective. However, drawbacks are the additional burden of drug use, the lack of a reduced mortality benefit and costs. Only with reliable risk prediction the recommendation of primary thromboprophylaxis will convince oncologists and patients of its usefulness. This review deals with clinical and laboratory parameters and their combination in risk assessment models to define patients at high and low risk of VTE, in whom targeted thromboprophylaxis could best be applied. At present 90% of patients in the so-called intermediate- to high-risk group according to the Khorana score still do not develop VTE during the first 6 months, whereas there is a high absolute number of patients in the so-called low-risk groups that develop VTE. Improvements in risk assessment have been made by new risk prediction models. However, additional refinements to further improve risk prediction and their applicability in clinical practice are still needed.

A prospective study of migraine history and venous thromboembolism in older adults

Unlabelled Box BackgroundLimited evidence suggests that migraine might be a risk factor for venous thromboembolism (VTE). We conducted an epidemiologic study to assess whether migraine history is associated prospectively with VTE or cross sectionally with hemostatic risk markers for VTE. MethodsIn a population‐based US cohort, 11 985 participants free of VTE reported headache symptoms in 1993‐1995. We classified participants as having either migraines with or without aura, severe nonmigraine headaches, or no severe headaches. We followed them through 2015 for incident VTE verified by medical records. ResultsParticipants’ mean age at baseline was 60 years (SD: 6). Eleven percent were classified as having a migraine history (932 without aura and 396 with aura). Over a mean of 18 years and 211 913 person‐years at risk, 688 participants developed VTE. Participants with a migraine history had no greater risk of VTE compared with those free of severe headache (adjusted hazard ratio [HR]: 1.06, 95% confidence interval [CI]: 0.82‐1.36). Those with migraine history with aura had an HR of 1.25 (95% CI: 0.85‐1.85). Self‐reported physician diagnosis of migraine carried an HR of 1.22 (0.96‐1.55). At baseline, those with a history of migraine, furthermore, did not have a higher frequency of elevated hemostatic risk factors or a higher genetic risk score for VTE. ConclusionThis study does not support the hypothesis that migraine history is an important risk factor for VTE in older adults.

The risk of venous thromboembolism in renal cell carcinoma patients with residual tumor thrombus

The clinical importance of tumor thrombus in patients with renal cell carcinoma is unknown. We sought to determine the long-term risk of venous thromboembolism (VTE) in patients with residual tumor thrombus postextraction, and to evaluate the impact of residual tumor thrombus on overall survival. A cohort study of patients with stage III-IV renal cell carcinoma undergoing nephrectomy was undertaken. The primary endpoint was the risk of VTE during a 2-year follow-up period. The secondary endpoint was 2-year overall survival. A total of 170 surgical renal cell carcinoma patients were included, 97 (57.1%) of whom had tumor thrombus. Patients with residual tumor thrombus following surgery had a higher risk of developing VTE than those with complete tumor thrombus resection (hazard ratio [HR] 8.7, 95% confidence interval [CI] 1.7-43.4) and no tumor thrombus (HR 6.5, 95% CI 1.7-24.7). Patient with residual tumor thrombus did not have worse overall survival than those with tumor thrombus completely resected or those without tumor thrombus. The presence of residual tumor thrombus is an important risk factor for VTE among renal cell carcinoma patients.

Inherited and Secondary Thrombophilia

Case Presentation 1: A healthy 19-year-old man presented with new chest pain and near syncope. Computed tomography pulmonary angiography showed a saddle pulmonary embolus. The patient denied recent travel, trauma, surgery, or hospitalization. His mother had 2 miscarriages at 10 weeks of gestation, and his maternal grandfather had deep venous thrombosis at 60 years of age. Case Presentation 2: A healthy 45-year-old woman reported new dyspnea and left calf pain. Computed tomography pulmonary angiography and compression venous duplex ultrasonography showed bilateral pulmonary emboli and acute left leg deep vein thrombosis, respectively. The patient denied exogenous hormone use, recent travel, trauma, surgery, or hospitalization. Her health maintenance was current, and she gave a family history of pernicious anemia, Grave disease, and amyotrophic lateral sclerosis. Laboratory analyses showed reduced hemoglobin (11.4 g/dL; normal, 12.0–15.5 g/dL), increased red blood cell distribution width (18.9%; normal, 11.9%–15.5%), and mild thrombocytopenia. Neither patient had previous venous thromboembolism, and both were referred to the Mayo Clinic Thrombophilia Center for apparent idiopathic venous thromboembolism. Thrombophilia is defined as a predisposition (susceptibility) to thrombosis. Thrombophilia is not a disease per se, but may be associated with a disease (eg, cancer), drug exposure (eg, oral contraceptives) or condition (eg, pregnancy or postpartum, secondary thrombophilia; Table 1), and thrombophilia may be inherited (Table 2).1 This concept is important because disease susceptibility does not imply an absolute requirement for primary or secondary prevention, or for treatment. Most persons with a thrombophilia do not develop thrombosis. Thus, thrombophilia must be considered in the context of other risk factors for incident thrombosis, or predictors of recurrent thrombosis, when estimating the need for primary or secondary prophylaxis, respectively. View this table: Table 1. Secondary Thrombophilia1 View this table: Table 2. Inherited Thrombophilia1 The role of special coagulation testing for an acquired or inherited thrombophilia is controversial. Thrombophilia testing should only be done if …

Increased Risk of Chemotherapy-Associated Venous Thromboembolism in Elderly Patients with Cancer

Data on the relationship between aging, chemotherapy, and risk for venous thromboembolism (VTE) are controversial. We sought to evaluate the risk of chemotherapy-associated VTE in young to middle-aged (YMA) and elderly cancer patients and to analyze the VTE-free survival time in both groups. Patients with histologically confirmed diagnosis of solid malignancy receiving any type of systemic chemotherapy, no clinical diagnosis of VTE before chemotherapy initiation, and Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≤2 were enrolled in this study. Of the 486 consecutive patients included in the study, 380 (78%) were classified as YMA (≤70 years of age) and 106 (22%) as elderly (>70 years of age). At a median follow-up of 1 year, the incidence of VTE events was almost two-fold greater in elderly than in YMA (11% vs. 6%). Age (≤70 years vs. >70 years (hazard ratio [HR], 2.42; 95% confidence interval [CI] 1.15-5.06; p=0.020), ECOG-PS (HR, 6.54; 95% CI 3.10-13.8; p<0.0001), and platinum-based chemotherapy (HR, 2.46; 95% CI 1.06-5.69; p=0.035) were independent risk factors for VTE. In the elderly subset, a trend toward an increased risk of VTE in patients receiving a platinum-based chemotherapy when compared with a non-platinum-containing regimen was observed (15% vs. 9.1%). The Kaplan-Meier analysis showed that elderly patients had a significantly shorter VTE-free survival time compared with younger cancer patients (log-rank test=2.0; p=0.045). Our study reports an increase incidence of VTE in elderly cancer patients treated with chemotherapy compared with the younger group, suggesting that aging is one of the most important risk factors for VTE. On the basis of the results of this study, we believe that a validated predictive model including age, ECOG-PS, and type of chemotherapy (platinum- vs. non-platinum containing regimen) would enable clinicians to target thromboprophylaxis to those patients considered to be at greatest risk.

Association between Thrombophilia and the Post-Thrombotic Syndrome

The post thrombotic syndrome (PTS) is a chronic condition that develops in 20%–40% of deep vein thrombosis (DVT) patients. While risk factors that predispose to the development of venous thromboembolism (VTE) are widely known, factors that influence the development of PTS after DVT have not been well elucidated. Over 10% of the general population is affected by one or more identifiable inherited thrombophilias which have been shown to underlie at least 1/3 of cases of VTE. The various thrombophilias are important risk factors for VTE, but it is unknown whether they also increase the risk for development of PTS. We performed a review of studies that have reported on the association between thrombophilia and the development of PTS in populations of patients with DVT and with chronic venous ulcers. Studies vary with regards to the definition of PTS, study design, follow-up period, and present conflicting results. Based on these results, the question of whether thrombophilia predisposes to the development of PTS remains unanswered.

The role of hypovitaminosis D in pregnancy-related venous thromboembolism

To the Editor: Venous thromboembolism (VTE) is a leading cause of maternal morbidity and mortality during pregnancy (1). Strategies of pharmacological thromboprophylaxis are based on balancing the perceived risk of thrombosis with the adverse effects of thromboprophylaxis. We propose that an important risk factor for VTE, which is easily overlooked, and which needs to be checked in this setting is hypovitaminosis D. Mounting evidence has shown a high prevalence of vitamin D deficiency during pregnancy (2). Hypovitaminosis D during pregnancy not only is linked to maternal skeletal preservation and fetal skeletal formation, but is also vital to the fetal ‘imprinting’ that may affect chronic disease susceptibility later in life as well as soon after birth (3, 4). On the other hand, it has been found that active sun exposure lowers the risk of thrombotic events (5), thus suggesting that variation in vitamin D status, strictly related to sun exposure, might be a plausible cause for the seasonal variation in thromboembolic complications. 1,25-dihydroxyvitamin [1,25(OH)2D], the active form of the vitamin D, has been shown to have anticoagulant properties by upregulating thrombomodulin and downregulating tissue factor (6). Furthermore, levels of 25-hydroxyvitamin D [25(OH)D], the measurable form of vitamin D, which better represents vitamin D status, have been shown to be inversely related to plasminogen activator inhibitor 1 and tissue-type plasminogen activator antigen levels (7), thus indicating that vitamin D is related to fibrinolytic activity and to the integrity of the vascular endothelium. Interestingly, a randomised controlled study of 250 patients with prostate cancer, half of whom were given 45 micrograms of 1,25(OH)2D weekly, found an unexpected significantly lower risk of thrombotic events (2 vs. 11) (8). On the basis of this evidence, it seems worthwhile to recommend to pregnant women that they supplement with vitamin D for global health benefits, and for VTE prevention in particular. A randomised controlled trial of vitamin D during pregnancy and lactation found that 4000 IU/d vitamin D3 was required for pregnant women to have sufficient 25(OH)D to control gene expression during fetal development and for nursing women to have sufficient unconverted vitamin D3 in their milk so the nursing infant can produce its own 25(OH)D (9). In addition, no adverse effects of this supplementation was found. In particular, there was no change in urine or serum calcium (9). It was therefore recommended that circulating 25(OH)D be 40–60 ng/ml (100–150 nmol/l) during pregnancy, and that a daily intake of 4000 IU vitamin D3 is required to attain that circulating concentration (10). Therefore, hypovitaminosis D should represent a potentially modifiable risk factor to be targeted at the beginning and during pregnancy, also to prevent thromboembolic complications. W.B.G. receives funding from the UV Foundation (McLean, VA), Bio-Tech Pharmacal (Fayetteville, AR), the Vitamin D Council (San Luis Obispo, CA), and the Vitamin D Society (Canada).

Association between Surgical Care Improvement Program venous thromboembolism measures and postoperative events

BackgroundIn 2006, the Surgical Care Improvement Program (SCIP) implemented measures to reduce venous thromboembolism (VTE). There are little data on whether these measures reduce VTE rates. This study proposed to examine associations between SCIP-VTE adherence and VTE rates. MethodsSCIP-VTE adherence for 30,531 surgeries from 2006 to 2009 was linked with VA Surgical Quality Improvement Program data. Patient demographics, comorbidities, and surgical characteristics associated with VTE were summarized. VTE rates were compared by SCIP-VTE adherence. Multivariable logistic regression was used to model VTE by adherence, adjusting for multiple associated factors. ResultsOf 30,531 surgeries, 89.9% adhered to SCIP-VTE; 1.4% experienced VTE. Logistic regression identified obesity, smoking, functional status, weight loss, emergent status, age older than 64 years, and surgical time as associated with VTE. SCIP-VTE was not associated with VTE (1.4% vs 1.33%; P = .3), even after adjustment. ConclusionsThis study identified several important risk factors for VTE but found no association with SCIP-VTE adherence.

Age- and Gender-Specific Familial Risks for Venous Thromboembolism

Background— This nationwide study sought to determine age- and gender-specific familial risks in siblings hospitalized for venous thromboembolism (VTE). Methods and Results— The Swedish Multigeneration Register on 0- to 75-year-old subjects was linked to the Hospital Discharge Register for the years 1987–2007. Standardized incidence ratios were calculated for individuals whose siblings were hospitalized for VTE compared with those whose siblings were not affected. Among a total of 45 362 hospitalized cases with VTE, 2393 affected siblings were identified, with a familial standardized incidence ratio of 2.45 (95% confidence interval [CI], 1.66 to 3.61). Gender-specific differences in incidence rates were observed. The familial risks were significantly increased from the age of 10 to 69 years, with a familial standardized incidence ratio of 4.77 (95% CI, 1.96 to 10.83) at ages 10 to 19 years, which decreased to 2.08 (95% CI, 1.35 to 3.20) at ages 60 to 69 years, although the absolute risk increased with age. The familial standardized incidence ratios for siblings with 2 and ≥3 affected probands were 51.87 (95% CI, 31.47 to 85.00) and 53.69 (95% CI, 25.59 to 108.50), respectively. Spouses had low familial risks (standardized incidence ratio=1.07; 95% CI, 1.04 to 1.10; observed spouse cases=3900). Conclusions— Familial factors, although influenced by age and gender, are important risk factors for VTE. The present study shows that VTE is aggregated in families and suggests that uncovering the sources of familial aggregation (genetic and nongenetic) may be worthwhile. Moreover, in a small fraction of siblings, the familial risk was very high, suggesting segregation of rare but strong genetic risk factors.

Antipsychotics and Venous Thromboembolism Risk: A Meta-Analysis

Antipsychotics have been inconclusively implicated in susceptibility to venous thromboembolism (VTE). The aim of this study was to investigate the association between antipsychotic drugs and VTE risk by a meta-analysis. PubMed and EmBASE databases were searched for publications through to 10 October 2010. Statistical analysis was performed using Revman 4.2 and Stata 10.0 software. 7 case-control studies involving 31 095 cases and 143 472 controls were analyzed. The results indicate that antipsychotic exposure confers a 139 % increased risk of VTE (odds ratio [OR] = 2.39, 95 % confidence interval [CI]:1.71–3.35). Pooled estimates by drug type showed that use of low-potency antipsychotics (OR = 2.91, 95 % CI 1.80–4.71) is the most important risk factor for VTE, followed by atypical (OR = 2.20, 95 % CI 1.22–3.96), conventional (OR = 1.72, 95 % CI 1.31–2.24) and high-potency drugs (OR = 1.58, 95 % CI 1.50–1.67). This meta-analysis suggests that antipsychotics are a risk factor for VTE. Additional studies in large cohorts are required to validate our findings. Future analyses should study potential eff ect modifications by different doses and durations of antipsychotic exposure in different populations.

Risk Factors for Venous Thromboembolism

Studies have suggested a link between risk factors for atherosclerotic disease and venous thromboembolism (VTE), but results are heterogeneous. We sought to identify risk factors for VTE with a focus on risk factors for atherosclerotic disease. Data were taken from the Copenhagen City Heart Study, a prospective cohort study of a random, age-stratified sample of people living in a defined area in Copenhagen, Denmark, started in 1976 with follow-up until 2007. First VTE (deep vein thrombosis and pulmonary embolism) diagnosis was retrieved from electronic national registries from study baseline to 2007. Of 18 954 subjects (median follow-up, 19.5 years) representing 360 399 person-years of follow-up, 969 subjects experienced at least 1 VTE, corresponding to a crude incidence rate of 2.69 (95% confidence interval [CI], 2.52 to 2.86) per 1000 person-years. The variables found to be significantly associated with VTE in a multivariable model adjusted for age and calendar time were as follows: body mass index (hazard ratio [HR] for >or=35 versus <20=2.10 [95% CI, 1.39 to 3.16]); smoking (HR for >or=25 g tobacco per day versus never smoker=1.52 [95% CI, 1.15 to 2.01]); gender (HR for men versus women=1.24 [95% CI, 1.08 to 1.42]); household income (HR for medium versus low=0.82 [95% CI, 0.70 to 0.95]); and diastolic blood pressure (HR for >100 versus <80 mm Hg=1.34 [95% CI, 1.08 to 1.66]). Other cardiovascular risk factors including total/high-density lipoprotein/low-density lipoprotein cholesterol levels, triglyceride levels, and diabetes mellitus were not associated with VTE. Obesity and smoking were both found to be important risk factors for VTE whereas total/high-density lipoprotein/low-density lipoprotein cholesterol levels, triglyceride levels, and diabetes mellitus were not.

Cancer-Associated Venous Thrombosis in the Surgical Setting

Cancer patients are at a relatively high risk of venous thromboembolism (VTE), and this has implications for surgical outcome. English literature search including the keywords cancer, surgery and VTE was undertaken to review the risk, etiology, prevention and treatment of VTE in surgical oncology patients. Malignant disease is highlighted as an important risk factor for VTE with an odds ratio of 6.5. The risk factors include higher age, previous VTE, advanced cancer, length of operation and immobility. Use of in-hospital thromboprophylaxis with low-molecular-weight heparin (LMWH) or low dose unfractionated heparin with graded stockings has been validated both in terms of safety and efficacy and should be considered for all patients. Subcutaneous LMWH has replaced unfractionated heparin for the initial treatment of VTE. The use of long-term LMWH instead of oral anticoagulants can substantially reduce the risk of recurrent VTE without increased bleeding. Recently, results of few trials have shown that LMWH may improve patient survival.

Prolonged seated immobility at work is a common risk factor for venous thromboembolism leading to hospital admission

The role of seated immobility at work in the pathogenesis of venous thromboembolism (VTE) is uncertain. In this case series, 61 patients aged <65 years with a recent admission for deep venous thrombosis and/or pulmonary embolism completed an interviewer-administered questionnaire to obtain information regarding risk factors. Prolonged seated immobility at work in the 4 weeks before the VTE event was defined as being seated at least 8 h in a 24-h period and at least 3 h at a time without getting up, at least 10 h in a 24-h period and at least 2 h at a time without getting up or at least 12 h in a 24-h period and at least 1 h at a time without getting up. The most commonly identified risk factors were family history of VTE (21 of 61, 34%), seated immobility at work (21 of 61, 34%) and a thrombophilic state (19 of 61, 31%). We conclude that prolonged seated immobility at work may represent a common and important risk factor for VTE.

Venous thromboembolism in association with features of the metabolic syndrome

Central obesity, diabetes mellitus, dyslipidaemia and chronic hypertension--features of the metabolic syndrome--have been individually associated with venous thromboembolism (VTE). However, whether each of these factors additively increases the risk of VTE is uncertain. To determine whether features of the metabolic syndrome independently increase the risk of VTE. Prospective cohort study derived from the Heart Outcomes Prevention Evaluation 2 (HOPE-2) randomized clinical trial. One hundred and forty-five clinical centres in 13 countries. We studied 5522 adults aged > or =55 years with cardiovascular disease or diabetes mellitus. At enrollment, 35% had 0-1 features of the metabolic syndrome, 30% had two, 24% had three and 11% had four. We defined symptomatic VTE as an objectively confirmed new episode of deep-vein thrombosis or pulmonary embolism. VTE occurred in 88 individuals during a median 5.0 years of follow-up. The incidence rate of VTE (per 100 person-years) was 0.30 with 0-1 features, 0.36 with two features, 0.38 with three features and 0.40 with four features of the metabolic syndrome (trend p = 0.43). Relative to the presence of 0-1 features of the metabolic syndrome, the adjusted hazard ratio (95%CI) for VTE was 1.22 (0.71-2.08) with two features, 1.25 (0.70-2.24) with three features, and 1.26 (0.59-2.69) with four features. The number of features of the metabolic syndrome present was not a clinically important risk factor for VTE in older adults with vascular arterial disease.

Cardiovascular Diseases and the Risk of Venous Thromboembolism: A Hospital-based Case-control Study

The effects of various cardiovascular diseases on the risk of venous thromboembolism (VTE) are not well defined. To gather more information, we performed a hospital-based case-control study to evaluate the effects of major cardiovascular diseases on the risk of VTE. We identified all incident cases of VTE needing hospitalization and anticoagulant therapy between January 1990 and December 2002 in a large tertiary hospital. Each case was matched with up to 4 controls, randomly selected from inpatients who were not hospitalized due to any of the exposures, on age, sex, calendar time and veteran/nonveteran status. This study comprised 173 cases of VTE and 546 matched controls. The adjusted odds ratio (OR) of VTE was significant among patients with peripheral atherosclerotic diseases (OR 7.1, 95% confidence interval [CI] 1.4-34.4), and nondebilitating cerebrovascular diseases (OR 2.5, 95% CI 1.4-4.7). Other independent risk factors for VTE included a body mass index>or=25.0 kg/m2, current estrogen use, a history of hyperlipidemia and varicose veins. Peripheral atherosclerotic disease and nondebilitating cerebrovascular disease are important risk factors for VTE. Patients with these diseases should therefore be frequently evaluated for the possible coexistence of VTE and, if appropriate, should be given prophylaxis. Failure to take into account the potential confounding effects of these diseases may also result in an erroneous estimate of the effect of drug exposures on the risk of idiopathic VTE.

Thrombophilia and pregnancy

Click to increase image sizeClick to decrease image sizeKeywords: Thrombophiliapregnancyfactor Vheparin