Impact of sex and traditional cardiovascular risk factors on the risk of recurrent venous thromboembolism: results from the German MAISTHRO Registry

Venous thrombosis and obesity: from clinical needs to therapeutic challenges

Weight bias and stigma have limited the awareness of the systemic consequences related to obesity. As the narrative evolves, obesity is emerging as a driver and enhancer of many pathological conditions. Among these, the risk of venous thromboembolism (VTE) is a critical concern linked to obesity, ranking as the third most common cardiovascular condition. Obesity is recognized as a multifactorial risk factor for VTE, influenced by genetic, demographic, behavioral, and socio-economic conditions. Despite established links, the exact incidence of obesity related VTE in the general population remains largely unknown. The complexity of distinguishing between provoked and unprovoked VTE, coupled with gaps in obesity definition and assessment still complicates a tailored risk assessment of VTE risk. Obesity reactivity, hypercoagulability, and endothelial dysfunction are driven by the so-called 'adiposopathy'. This state of chronic inflammation and metabolic disturbance amplifies thrombin generation and alters endothelial function, promoting a pro-thrombotic environment. Additionally, the inflammation-induced clot formation-also referred to as 'immunothrombosis' further exacerbates VTE risk in people living with obesity. Furthermore, current evidence highlights significant gaps in the management of obesity related VTE, particularly concerning prophylaxis and treatment efficacy of anticoagulants in people living with obesity. This review underscores the need for tailored therapeutic approaches and well-designed clinical trials to address the unique challenges posed by obesity in VTE prevention and management. Advanced research and innovative strategies are imperative to improve outcomes and reduce the burden of VTE in people living with obesity.

Venous Thromboembolism Issues in Women

The lifetime risk of venous thromboembolism (VTE) is slightly higher in women than in men. There are several issues related to VTE that are unique to women. Combined hormonal contraceptives and pregnancy increase the risk of VTE in women of childbearing age, whereas hormone replacement therapy increases the VTE risk of postmenopausal women. Hereditary thrombophilia and risk factors such as older age, obesity, or smoking contribute to the risk increase. In women diagnosed with acute hormone-related VTE who are treated with oral anticoagulants, adequate contraception is mandatory to avoid unwanted pregnancies. According to current knowledge, hormonal contraception may be continued during anticoagulant therapy but must be switched to an estrogen-free contraception method at least 6 weeks before the termination of anticoagulation. VTE is also a major cause of maternal morbidity and mortality during pregnancy and the postpartum period. Currently, assisted reproduction technologies such as in vitro fertilization are widely used to treat couples affected by infertility. Complications of fertility treatment comprise VTE cases, especially in women with ovarian hyperstimulation syndrome. With this review, we intended to focus on VTE issues in women and summarize current evidence and guideline recommendations.

Obesity as a Risk Factor for Venous Thromboembolism Recurrence: A Systematic Review

Background and Objectives: Venous thromboembolism (VTE) encompasses Deep Venous Thrombosis (DVT) and Pulmonary Embolism (PE). The duration of anticoagulant therapy following a VTE event partly relies on the risk of recurrent VTE which depends on the clinical setting where VTE occurred and the VTE risk factors present. Obesity is considered a minor risk factor and studies in the literature have provided conflicting results on whether obesity influences the development of recurrences. The aim of the present study is to assess the effect of obesity on VTE recurrence in patients that suffered from a previous VTE event. Materials and Methods: We conducted systematic research for English language studies in Medline, Scopus and ProQuest databases in order to identify publications that assess the risk of VTE recurrence in obesity. Inclusion criteria were: 1. Diagnosis of VTE, 2. Definition of obesity as a body mass index ≥30 kg/m², 3. Report of the risk of obesity on VTE recurrence, 4. Adult human population. We did not include case reports, review studies or studies that assessed other forms of thrombosis and/or used other definitions of obesity. We used the Newcastle-Ottawa scale to address the quality of the studies. Results: Twenty studies were included in the analysis, of which 11 where prospective cohort studies, 6 were retrospective cohort studies, 1 was a cross-sectional study, and 2 were post-hoc analysis of randomized clinical trials. Obesity was significantly associated with recurrences in 9 studies and in 3 of them the association was significant only in females. Conclusions: There is heterogeneity between the studies both in their design and results, therefore the effect of obesity on VTE recurrence cannot be adequately estimated. Future randomized clinical studies with appropriately selected population are needed in order to streamline the effect of obesity on VTE recurrence.

Prognostic Impact of Active Cigarette Smoking on Mortality in Patients with Acute Venous Thromboembolic Events, Findings from Real World Data

Background and Objectives: The influence of smoking habits on mortality, VTE recurrence, and major bleeding in patients receiving anticoagulant therapy for venous thromboembolism (VTE) has not been consistently evaluated. Materials and Methods: We used data from the RIETE (Registro Enfermedad TromboEmbólica) registry to compare mortality, VTE recurrence, and major bleeding risk in smoking versus non-smoking patients with acute VTE. Results: 50,881 patients (43,426 non-smoking and 7455 smoking patients) were included. After a median follow-up of 8.8 months, 7110 patients died (fatal PE 292 and fatal bleeding 281), 3243 presented VTE recurrence, and 1579 had major bleeding. At multivariate analysis, smoking behavior was associated with a higher hazard of death, (HR: 1.28; 95% CI: 1.19–1.40). The risk of VTE recurrence was marginally increased in smoking patients compared to non-smoking patients (1.14; 95% CI: 1.02–1.27). Major bleeding did not differ in smoking and non-smoking patients (1.15; 95% CI: 0.96–1.38). The presence of cancer did not appear to influence the association between smoking habits and death (HR: 1.34; 95% CI: 1.22–1.47 in cancer patients and HR: 1.23; 95% CI: 1.04, 1.45 in non-cancer patients, respectively) Conclusions: the risk of death after an acute episode of VTE appeared to be higher in smoking than in non-smoking patients and this risk is higher between patients presenting PE at the onset of symptoms.

Is pulmonary embolism recurrence linked with the severity of the first event? A French retrospective cohort study

OBJECTIVES

Severity of a first pulmonary embolism (PE) is sometimes proposed as a criterion for prolonging anticoagulant treatment. However, little evidence supports this idea. We attempted to determine the connection between severity of first PE and the risk of recurrence.

PARTICIPANTS

Patients admitted with PE between 2012 and 2018 and for whom anticoagulant treatment had been discontinued were followed. PEs were classified according to the severity into the following two groups: those with associated cardiac involvement (increased cardiac biomarker(s) and/or echocardiographic right ventricular dysfunction) and those with no cardiac involvement which were classified as non-severe. Recurrence-free survivals were estimated using the Kaplan-Meier method and compared using the log-rank test.

RESULTS

417 patients with PEs (186 with cardiac involvement) were followed for at least 1 year after discontinuation of treatment with a mean follow-up of: 3.5±1.9 years. 72 patients (17.3%) experienced venous thromboembolism recurrence: 24 (5.8%), 44 (12 %) and 72 (28.3 %) respectively, at 1, 2 and 5 years. In 63 patients (88%), recurrence was a PE. Mean time to onset of recurrence was 24.9±19.9 months. At 5 years, the recurrence rate is higher when the first PE was associated with cardiac involvement p=0.043. In contrast, in patients with provoked PE, the recurrence rate is higher when the first PE event was associated with cardiac involvement: p=0.032. Multivariate analysis demonstrates that PE severity is an independent factor of recurrence (HR 1.634 (1.015-2.632), p=0.043).

CONCLUSION

We report for the first time a possible link between a higher recurrence rate and the severity of the first PE. This result which must be confirmed in a dedicated prospective trial could become an important criterion for the duration of anticoagulant therapy after a PE.

TRIAL REGISTRATION NUMBER

NCT04980924.

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.

Crucial considerations: Sex differences in the epidemiology, diagnosis, treatment, and outcomes of acute pulmonary embolism in non-pregnant adult patients

Acute pulmonary embolism (PE) affects over 600,000 Americans per year and is a common diagnostic consideration among emergency department patients. Although there are well-documented differences in the diagnosis, treatment, and outcomes of cardiovascular conditions, such as ischemic heart disease and stroke, the influence of sex and gender on PE remains poorly understood. The overall age-adjusted incidence of PE is similar in women and men, but women have higher relative rates of PE during early and mid-adulthood (ages 20-40 years); whereas, men have higher rates of PE after age 60 years. Women are tested for PE at far higher rates than men, yet women who undergo computed tomography pulmonary angiography are ultimately diagnosed with PE 35%-55% less often than men. Among those diagnosed with PE, women are more likely to have severe clinical features, such as hypotension and signs of right ventricular dysfunction. When controlled for PE severity, women are less likely to receive reperfusion therapies, such as thrombolysis. Finally, women have more bleeding complications for all types of anticoagulation. Further investigation of possible sex-specific diagnostic and treatment algorithms is necessary in order to more accurately detect and treat acute PE in non-pregnant adults.

Risk of Stroke in Patients With Patent Foramen Ovale Who Had Pulmonary Embolism

Background

The presence of patent foramen ovale (PFO) alone does not increase the risk of ischemic stroke. Several prospective studies with a small number of patients have shown that the risk of ischemic stroke is higher in patients with PFO and pulmonary embolism (PE). We studied the association of ischemic stroke in the patients who had PFO with PE (PFOwiPE) and compared with the patients who had PFO without PE (PFOwoPE).

Methods

Electronic medical records of 154 adult patients in our internal medicine office were reviewed. Thirty-four patients had PFOwiPE and 120 had PFOwoPE. Independent t-test and Mann-Whitney U-test were used to compare the continuous variables between the two groups, while Chi-square tests were applied to compare the categorical variables between the two groups. Logistic regression was used for multivariate analysis. The dependent variable was stroke and the independent variable of interest was PFO with, or without PE.

Results

Mean age of patients with PFOwiPE was 54.8 years and patients with PFOwoPE was 57.8 years (P = 0.331). Mean body mass index (BMI) of the patients with PFOwiPE was significantly greater than the patients with PFOwoPE (32.5 ± 8.84 kg/m² vs. 28.4 ± 6.99 kg/m²; P < 0.05). Mean left ventricular ejection fraction (LVEF) and red blood cell (RBC) count of patients with PFOwiPE was significantly lower than patients with PFOwoPE (LVEF 54.9 ± 13.01% vs. 59.6 ± 6.85%, P < 0.05; RBC 4.1 ± 1.203 × 10⁶/µL vs. 4.5 ± 0.596 × 10⁶/µL, P < 0.05). There was significantly higher association of congestive heart failure (CHF) in patients with PFOwiPE compared to patients with PFOwoPE (20.6% vs. 7.5%; P < 0.05). Association of ischemic stroke was 35.3% in patients with PFOwiPE and 39.2% in patients with PFOwoPE. The difference was not statistically significant (P = 0.682).

Conclusions

Association of ischemic stroke was similar in patients with PFOwiPE and patients with PFOwoPE. Association of significantly higher BMI, lower LVEF, lower RBC count, and higher frequency of CHF were associated with patients with PFOwiPE compared to the patients with PFOwoPE.

Prognostic characteristics and body mass index in patients with pulmonary embolism: does size matter?

Objective

The aim of this study was to explore the impact of body mass index (BMI) on prognostic indicators and clinical outcomes in patients with pulmonary embolism.

Methods

Patients with pulmonary embolism from the Hokusai venous thromboembolism (VTE) randomised clinical trial that compared two anticoagulant regimens were followed-up for 1 year (n=1911). Patients were analysed with regard to World Health Organization (WHO) BMI categories at baseline (underweight (<18.5), normal (18.5 to <25), overweight (25 to <30), obese I (30 to <35), obese II (35 to <40), and obese III (≥40)). Clinical and radiological prognostic characteristics for right ventricular dysfunction and adverse events were assessed with normal weight as a reference. Clinical outcomes were mortality, recurrent VTE, hospitalisation, bleeding and overall adverse events.

Results

The relationship between BMI categories and both prognostic parameters and clinical outcomes showed U-shaped curves. Adjusted odds ratios (aORs) were highest in patients who were grade III obese for both clinical parameters (N-terminal pro-brain natriuretic peptide (NT-proBNP) >600 and simplified pulmonary embolism severity index (sPESI)≥1; 2.9 and 1.6), and radiological parameters (pulmonary trunk>29 mm, right-to-left-ventricular ratio>1.0, and central emboli; aOR=4.3, 2.1 and 2.3). Bleeding was observed more frequently in the higher categories of obesity. In patients who were underweight, for NT-proBNP>600 and sPESI≥1 the aORs were 2.6 and 2.5, respectively; however, no major bleeding occurred in this category.

Conclusion

Several clinical and radiological prognostics characteristics and right ventricular dysfunction in pulmonary embolism are not evenly distributed among BMI categories. This is reflected in a trend towards worse outcomes in patients who are overweight and underweight.

Overweight patients with pulmonary embolism have a higher risk of heart dysfunction and worse outcomeshttp://bit.ly/2Pwtln0

Obesity Paradox in Patients With Deep Venous Thrombosis

We aimed to investigate the association between obesity and deep venous thrombosis (DVT) in a country with a high prevalence of obesity. This is a retrospective cohort study of patients who presented with DVT between 2008 and 2012. Data were analyzed and compared based on body mass index (BMI), and patients were classified into normal (<25), overweight (≥25 to <30), obese I (30 to <35), obese II (35 to <40), and obese III (≥40). Among 662 patients with DVT, 28% were overweight and 49% were obese. The mean age was 50.3 (16.5) years, and 51% were females. Diabetes mellitus and prior venous thromboembolism were significantly higher among obese patients. History of malignancy was more common in nonobese patients. Protein S and antithrombin III deficiency and hyperhomocysteinemia were more prevalent among morbid obese patients. Also, obese patients had higher incidence of thrombosis in the distal veins ( P = .03). Warfarin use and long-term therapy were more frequent in obese than nonobese. Postthrombotic syndrome was comparable in obese and nonobese groups. Recurrent DVT was higher in obese I ( P < .01), whereas mortality rates were greater in nonobese groups ( P = .001). Malignancy, diabetes mellitus, and common femoral vein involvement were predictors of mortality, whereas BMI ≥30 was the predictor of survival. Cox regression models showed that after adjusting for age, sex, pulmonary embolism, and duration of warfarin treatment, BMI ≥40 had better survival (hazard ratio: 0.177, 95% confidence interval: 0.045-0.691, P = .013). There is a significant association between obesity and DVT. Obese patients have characteristic risk factors and better survival. This obesity paradox needs further studies to assess its clinical and pharmacotherapeutic implications.

Venous and Arterial Thrombosis: Is There a Link?

An increasing body of evidence suggests the likelihood of a link between venous and arterial thrombosis. The two vascular complications share several risk factors, such as age, obesity, smoking, diabetes mellitus, blood hypertension, hypertriglyceridemia, and metabolic syndrome. Moreover, there are many examples of conditions accounting for both venous and arterial thrombosis, such as the antiphospholipid antibody syndrome, hyperhomocysteinemia, malignancies, infections, and the use of hormonal treatment. Finally, several recent studies have consistently shown that patients with venous thromboembolism are at a higher risk of arterial thrombotic complications than matched control individuals. We, therefore, speculate the two vascular complications are simultaneously triggered by biological stimuli responsible for activating coagulation and inflammatory pathways in both the arterial and the venous system. Future studies are needed to clarify the nature of this association, to assess its extent, and to evaluate its implications for clinical practice.

Association between smoking and recurrence of venous thromboembolism and bleeding in elderly patients with past acute venous thromboembolism

BACKGROUND

While the association between smoking and arterial cardiovascular events has been well established, the association between smoking and venous thromboembolism (VTE) remains controversial.

OBJECTIVES

To assess the association between smoking and the risk of recurrent VTE and bleeding in patients who have experienced acute VTE.

PATIENTS/METHODS

This study is part of a prospective Swiss multicenter cohort that included patients aged ≥65years with acute VTE. Three groups were defined according to smoking status: never, former and current smokers. The primary outcome was the time to a first symptomatic, objectively confirmed VTE recurrence. Secondary outcomes were the time to a first major and clinically relevant non-major bleeding. Associations between smoking status and outcomes were analysed using proportional hazard models for the subdistribution of a competing risk of death.

RESULTS

Among 988 analysed patients, 509 (52%) had never smoked, 403 (41%) were former smokers, and 76 (8%) current smokers. After a median follow-up of 29.6months, we observed a VTE recurrence rate of 4.9 (95% confidence interval [CI] 3.7-6.4) per 100 patient-years for never smokers, 6.6 (95% CI 5.1-8.6) for former smokers, and 5.2 (95% CI 2.6-10.5) for current smokers. Compared to never smokers, we found no association between current smoking and VTE recurrence (adjusted sub-hazard ratio [SHR] 1.05, 95% CI 0.49-2.28), major bleeding (adjusted SHR 0.59, 95% CI 0.25-1.39), and clinically relevant non-major bleeding (adjusted SHR 1.21, 95% CI 0.73-2.02).

CONCLUSIONS

In this multicentre prospective cohort study, we found no association between smoking status and VTE recurrence or bleeding in elderly patients with VTE.

Is lipid lowering therapy an independent risk factor for venous thromboembolism? A population-based case-control study

INTRODUCTION

The independent effect of lipid lowering therapy (LLT) on venous thromboembolism (VTE) risk is uncertain.

OBJECTIVE

To test statin and non-statin LLT as potential VTE risk factors.

METHODS

Using Rochester Epidemiology Project resources, we identified all Olmsted County, MN residents with objectively diagnosed incident VTE (cases) over the 13-year period, 1988-2000 (n=1340), and one to two matched controls (n=1538). We reviewed their complete medical records for baseline characteristics previously identified as independent VTE risk factors, and for statin and non-statin LLT. Using conditional logistic regression, we tested the overall effect of LLT on VTE risk and also separately explored the role of statin versus that of non-statin LLT, adjusting for other baseline characteristics.

RESULTS

Among cases and controls, 74 and 111 received statin LLT, and 32 and 50 received non-statin LLT, respectively. Univariately, and after individually controlling for other potential VTE risk factors (i.e., BMI, trauma/fracture, leg paresis, hospitalization for surgery or medical illness, nursing home residence, active cancer, central venous catheter, varicose veins, prior superficial vein thrombosis, diabetes, congestive heart failure, angina/myocardial infarction, stroke, peripheral vascular disease, smoking, anticoagulation), LLT was associated with decreased odds of VTE (unadjusted OR=0.73; p=0.03). When considered separately, statin and non-statin LLT were each associated with moderate, non-significant lower odds of VTE. After adjusting for angina/myocardial infarction, each was significantly associated with decreased odds of VTE (OR=0.63, p<0.01 and OR=0.61, p=0.04, respectively).

CONCLUSIONS

LLT is associated with decreased VTE risk after adjusting for known risk factors.

Risk Characteristics of Venous Thromboembolism in Chinese Patients

BACKGROUND AND OBJECTIVE

There is little report concerning risk characteristics of Chinese patients with venous thromboembolism (VTE). The present study was designed to investigate the risk characteristics in Chinese patients with VTE through a retrospective study.

METHODS

A total of 1048 registry patients with VTE in the recent 10 years were analyzed retrospectively with respect to underlying diseases or predisposing factors.

RESULTS

The incidence of VTE in both male and female has been increasing in the recent 10 years. A total of 885 patients were aged more than 50 years, and the mean age of the patients at diagnosis was 58.8 ± 15.7 years. Main risk factors were a prolonged immobilization and malignant tumors, which were different from Western patients.

CONCLUSIONS

This registry demonstrated the different risk characteristics in Chinese patients compared to Western patients. Our results will be available for establishing the prevention of VTE in China.

Infections increase risk of arterial and venous thromboses in Danish patients with systemic lupus erythematosus: 5102 patient-years of followup

OBJECTIVE

Infections and thromboses are known complications of systemic lupus erythematosus (SLE). We investigated if infectious episodes in patients with SLE were followed by an increased risk of thrombotic events.

METHODS

A cohort of 571 patients with prevalent or incident SLE was followed for a mean of 8.9 ± 7.6 years. All episodes of hospitalized infections or episodes of cutaneous herpes zoster as well as arterial and venous thrombotic events were identified by retrospective chart review and prospective updating of a clinical database. For time-dependent analyses adjusted for age, sex, and ever-presence of antiphospholipid antibodies, thrombotic events were classified as occurring during the time at risk of 1 year after an infection or during the remaining control observation time.

RESULTS

Of 271 infections identified, 104 were respiratory, 41 cutaneous herpes zoster, and 126 others. Of 159 thromboses identified, 98 were arterial. Incidence for arterial and venous thromboses within 1 year after infection was 2.18% and 2.56%, respectively, compared to patients who never had an infection (0.58 and 0.67). The adjusted 1-year risk of arterial and venous thrombosis after any infection was increased [relative rate (RR) 2.5, 95% CI 1.4-4.6, and RR 2.8, 95% CI 1.3-5.9, respectively]. Venous thromboses were in particular more prevalent after respiratory infections (RR 5.4, 95% CI 2.3-13).

CONCLUSION

The temporal associations observed in this study indicate that infections could be risk factors for arterial or venous thromboses in patients with SLE, although causality was not addressed by this study.

Risk marker associations with venous thrombotic events: a cross-sectional analysis

OBJECTIVE

To examine the interrelations among, and risk marker associations for, superficial and deep venous events-superficial venous thrombosis (SVT), deep venous thrombosis (DVT) and pulmonary embolism (PE).

DESIGN

Cross-sectional analysis.

SETTING

San Diego, California, USA.

PARTICIPANTS

2404 men and women aged 40-79 years from four ethnic groups: non-Hispanic White, Hispanic, African-American and Asian. The study sample was drawn from current and former staff and employees of the University of California, San Diego and their spouses/significant others.

OUTCOME MEASURES

Superficial and deep venous events, specifically SVT, DVT, PE and combined deep venous events (DVE) comprising DVT and PE.

RESULTS

Significant correlates on multivariable analysis were, for SVT: female sex, ethnicity (African-American=protective), lower educational attainment, immobility and family history of varicose veins. For DVT and DVE, significant correlates included: heavy smoking, immobility and family history of DVEs (borderline for DVE). For PE, significant predictors included immobility and, in contrast to DVT, blood pressure (BP, systolic or diastolic). In women, oestrogen use duration for hormone replacement therapy, in all and among oestrogen users, predicted PE and DVE, respectively.

CONCLUSIONS

These findings fortify evidence for known risk correlates/predictors for venous disease, such as family history, hormone use and immobility. New risk associations are shown. Striking among these is an association of PE, but not DVT, to elevated BP: we conjecture PE may serve as cause rather than consequence. Future studies should evaluate the temporal direction of this association. Oxidative stress and cell energy compromise are proposed to explain and predict many risk factors, operating through cell-death mediated triggering of coagulation activation.

Prevalence of thrombophilia according to age at the first manifestation of venous thromboembolism: results from the MAISTHRO registry

Thrombophilia is a well-established risk factor for a venous thromboembolic event (VTE), and it has been proposed that hereditary thrombophilia may substantially contribute to the development of VTE in young patients. We aimed to analyse the prevalence of thrombophilia with special regard to the age of VTE manifestation. The study cohort consisted of 1490 patients (58% females) with a median age 43 years at the time of their first VTE. At least one thrombophilic disorder was identified in 50·1% of patients. The probability of detecting a hereditary thrombophilia declined significantly with advancing age (from 49·3% in patients aged 20 years and younger to 21·9% in patients over the age of 70 years; P < 0·001). This may be primarily attributed to the decreasing frequencies of the F5 R506Q (factor V Leiden) mutation and deficiencies of protein C or protein S with older age at the time of the initial VTE event. Moreover, thrombophilia was more prevalent in unprovoked compared with risk-associated VTE (57·7% vs. 47·7%; P = 0·001). The decline in the prevalence of hereditary thrombophilia with older ages supports the use of a selected thrombophilia screening strategy dependent on age and the presence or absence of additional VTE risk factors.

Adding chemoprophylaxis to sequential compression might not reduce risk of venous thromboembolism in bariatric surgery patients

BACKGROUND

Anticoagulation, the use of sequential compression devices on the lower extremities perioperatively, and early ambulation are thought to reduce the incidence of venous thromboembolism (VTE) postoperatively and are recommended to reduce VTE risk. However, the evidence on which this recommendation has been based is not particularly strong. We have demonstrated that even a large, multicenter cohort with carefully collected prospective data is inadequate to provide sufficient evidence to support, or refute, this recommendation.

METHODS

Longitudinal Assessment of Bariatric Surgery participants from 10 centers in the United States who underwent their first bariatric surgery between March 2005 and December 2007 constituted the study group. We examined the ability to address the question of whether anticoagulation therapy, in addition to sequential compression, reduces the 30-day incidence of VTE or death sufficiently to recommend the use of prophylactic anticoagulation, a therapy that is not without risk.

RESULTS

Of 4416 patients, 396 (9.0%) received sequential compression alone, and 4020 also received anticoagulation therapy. The incidence of VTE within 30 days of surgery was low (.25% among those receiving sequential compression alone and .47% when anticoagulation therapy was added), and the 30-day incidence of death was also low (.25% versus .34%, respectively, P = .76, for sequential compression alone versus sequential compression plus anticoagulation therapy). Estimates of the number of cases required to address the question of whether a difference exists in the outcome related to VTE chemoprophylaxis or whether the outcome rates are equivalent have ranged from 13,680 to ≥ 35,760 patients, depending on whether superiority or equivalence was being analyzed.

CONCLUSION

Sufficient evidence from a clinical trial study to determine whether prophylactic anticoagulation added to compression devices further prevents VTE is not available, and such a trial is likely to be impractical. The data presented are insufficient to make a final recommendation concerning prophylactic treatment to prevent VTE in the 30 days after bariatric surgery.

The effects of obesity on venous thromboembolism: A review

Obesity has emerged as a global health issue that is associated with wide spectrum of disorders, including coronary artery disease, diabetes mellitus, hypertension, stroke, and venous thromboembolism (VTE). VTE is one of the most common vascular disorders in the United States and Europe and is associated with significant mortality. Although the association between obesity and VTE appears to be moderate, obesity can interact with other environmental or genetic factors and pose a significantly greater risk of VTE among individuals who are obese and who are exposed simultaneously to several other risk factors for VTE. Therefore, identification of potential interactions between obesity and certain VTE risk factors might offer some critical points for VTE interventions and thus minimize VTE morbidity and mortality among patients who are obese. However, current obesity measurements have limitations and can introduce contradictory results in the outcome of obesity. To overcome these limitations, this review proposes several future directions and suggests some avenues for prevention of VTE associated with obesity as well.

Recurrent venous thromboembolism: what is the risk and how to prevent it

Venous thromboembolism (VTE) that includes deep vein thrombosis and/or pulmonary embolism is a frequent, severe, and potentially lethal disease. After a first episode, VTE has a strong tendency to recur. While VTE is an acute disease, it may have variable outcomes in early and late phases after initial presentation. Furthermore, the incidence of late, clinically important consequences (postthrombotic syndrome and/or chronic thromboembolic pulmonary hypertension) increases in case of recurrent events. The aims of the present review are (i) to analyze the incidence and risk factors for recurrence of VTE (either those related to the type of first thrombotic event or to the patients), the risks associated with occurrence of recurrent events, and the problems linked to the diagnosis, not always easy, of recurrent events; (ii) to discuss whether or not it is possible to predict the individual risk of recurrence after a first event, by stratifying patients at high or low risk of recurrence, and how this can influence their treatment; (iii) to comment what the current guidelines and guidance suggest/recommend about anticoagulant treatment after a first VTE event and, finally, to propose practical indications on how to manage individual patients affected by VTE.

Abnormally high prevalence of major components of the metabolic syndrome in subjects with early-onset idiopathic venous thromboembolism

BACKGROUND

Although patients with idiopathic VTE are at higher than normal risk of asymptomatic atherosclerosis and of cardiovascular events, the impact of cardiovascular risk factors on VTE is poorly understood.

OBJECTIVE

To assess the prevalence of the metabolic syndrome and of its components in patients with early-onset idiopathic VTE.

METHODS

As many as 323 patients referred to our Thrombosis Ward for a recent (<6-months) early-onset idiopathic venous thromboembolism (VTE), were compared with 868 gender- and age-matched subjects, in whom a history of venous thrombosis had been excluded, referred during the same period time to our Ward. All had undergone a clinical assessment for smoking habits and for the presence of the components of the metabolic syndrome.

RESULTS

The metabolic syndrome was detected in 76/323 cases (23.5%) and in 81/868 controls (9.3%) (p<0.001; OR:2.990; 95%C.I.:2.119-4.217). Smoking was more common in patients with idiopathic VTE than in controls. In addition to the metabolic syndrome as a whole, its major individual determinants (arterial hypertension, impaired fasting glucose plasma levels, abdominal obesity, hypertriglyceridemia, low HDL-cholesterol) significantly correlated with idiopathic VTE (p always <0.05). The prevalence of thrombotic events was lower in females than in males (p=0.000; OR:2.217), the latter being most often hypertensives, smokers, hypertriglyceridemics, carriers of a metabolic syndrome and of impaired fasting glucose than females. In a multivariate analysis, arterial hypertension, impaired fasting glucose, abdominal obesity, and hypercholesterolemia independently predicted idiopathic venous events.

CONCLUSIONS

Both metabolic syndrome as a whole and its major components individually considered, independently predict early-onset idiopathic VTE.

High prevalence of nonalcoholic fatty liver in patients with idiopathic venous thromboembolism

AIM

to assess the prevalence of nonalcoholic fatty liver disease (NAFLD) in patients with idiopathic venous thromboembolism (VTE).

METHODS

in a case-control study, after excluding subjects with well-consolidated risk factors for VTE, idiopathic VTE was documented in 138 consecutive patients who were referred to our department. Two hundred and seventy-six healthy sex/age/body-mass-index-matched subjects, without any clinical/instrumental evidence of VTE, served as controls. All underwent a clinical/laboratory/ultrasound assessment for the presence of metabolic syndrome and NAFLD.

RESULTS

NAFLD was detected in 112/138 cases (81%) and in 84/276 controls (30%) [risk ratio: 2.7, 95% confidence interval (CI): 2.2-3.2, P < 0.0001]. Metabolic syndrome and smoking habit were more prevalent in patients with idiopathic VTE. The high prevalence of NAFLD in VTE was also confirmed after adjustment for inherited thrombophilia. NAFLD was clearly predicted by VTE (odds ratio: 1.8, 95% CI: 1.2-2.7, P < 0.0001).

CONCLUSION

NAFLD was independently associated with idiopathic VTE.

Sex difference in risk of recurrent venous thrombosis and the risk profile for a second event

BACKGROUND

The risk of recurrent venous thrombosis is higher in men than in women, and this is so far unexplained. We set out to determine the influence of age, time between first and second event, type of first event, oral contraception, pregnancy and surgery.

METHODS

We performed a prospective follow-up study of 474 patients with a first objective diagnosis of deep vein thrombosis, aged 18-70 years (Leiden Thrombophilia Study cohort).

RESULTS

During 3477 person-years of follow-up, 90 recurrences occurred. The overall incidence rates of recurrence (IRs) were 40.9 per 1000 person-years in men and 15.8 per 1000 person-years in women. Men with an unprovoked first event had the highest risk of recurrence, with almost one-third experiencing a second unprovoked event within 8 years (IR 41.2 per 1000 person-years). This risk was three-fold lower in women [IR 14.2 per 1000 person-years; hazard ratio 2.8 (95% confidence interval 1.4-5.7)]. Age at diagnosis had little effect on recurrence rate, and nor had time elapsed since the first event. In women, almost half of the recurrences were provoked and were mainly related to oral contraceptive use or pregnancy.

CONCLUSIONS

The higher recurrence rate in men than in women is not the result of differences in the environmental or transient risk factors that we studied. The risk profile for a second thrombotic event is clearly different from that of a first.

Impact and clinical significance of recurrent venous thromboembolism

Background

The purpose of this review was to analyse current knowledge and controversies associated with the diagnosis, treatment and prevention of recurrent venous thromboembolism (VTE).

Methods

MEDLINE and manual searches were performed to select prospective papers on the diagnosis, treatment and prevention of recurrent VTE for their relevance and quality.

Results

The cumulative incidence of recurrent VTE increases from 11 per cent at 1 year to 40 per cent at 10 years. The incidence of recurrence is higher in unprovoked thrombosis compared with provoked VTE. Patients with unprovoked deep vein thrombosis also have a greater number of multiple recurrences. Ultrasonography or D-dimer monitoring may have an impact on the duration of anticoagulation but further refinements are needed. The incidence of skin damage is higher in ipsilateral recurrence compared with contralateral or no recurrence. Legs with ipsilateral recurrence more often have both reflux and obstruction.

Conclusion

The role and weight of the predictive factors for recurrent VTE and its sequelae, and the type and optimal duration of anticoagulation have not been studied adequately. Fatality associated with pulmonary embolism and rates of recurrent VTE remain unacceptably high.

Recurrent deep vein thrombosis: long-term incidence and natural history

OBJECTIVE

To determine the long-term incidence, risk factors, and associated morbidity and mortality of recurrent deep vein thrombosis (DVT).

SUMMARY BACKGROUND DATA

Few studies have examined the long-term natural history and impact of recurrent DVT.

METHODS

We conducted a prospective observational study that followed 153 consecutive patients with an acute first episode of DVT. Clinical examination and ultrasound were performed serially for at least 5 years. Location and extent of the initial DVT, recurrence, pulmonary embolism, cause of mortality, signs and symptoms of post thrombotic syndrome (PTS), and the risk factors were recorded.

RESULTS

The incidence of recurrence at 5 years was 26.1%. Patients with both proximal and distal DVT had a higher recurrence rate than proximal (17/48 35% vs. 12/49, 24%, P = 0.27) or calf alone (11/56, 20%, P = 0.08). Unprovoked DVT and age >65 years were associated with higher recurrence rates (P < 0.001; relative risk [RR]: 2.9, 95% confidence interval [CI]: 1.5-5.7) and (P = 0.025; RR: 1.5, 95% CI: 1-2.3), respectively. Thrombophilia was not associated with increased risk of recurrence (P = 0.21). Patients with DVT due to surgery or trauma had a lower recurrence (P < 0.001). Ipsilateral recurrence was associated with increased severity of PTS (P < 0.001; RR: 1.6, 95% CI: 1.4-2.2). PE occurred 47 times, 12 (25%) of which were fatal events.

CONCLUSIONS

Factors associated with a higher rate of recurrence included unprovoked DVT and age >65. Elevated thrombus burden had a trend towards higher risk. Patients with surgery and trauma had low recurrence rates. Ipsilateral recurrence was strongly associated with PTS. PE occurred frequently and was a common cause of death.

Prospective study of BMI and the risk of pulmonary embolism in women

Pulmonary embolism (PE) is common and associated with significant morbidity and mortality. An association between obesity and PE has been suggested, but the nature of the association has not been well defined. We performed a prospective cohort study of 87,226 women in the Nurses' Health Study (1984-2002) to define the association between BMI and the risk of incident PE. Primary exposure was BMI (<22.5, 22.5-24.9, 25.0-27.4, 27.5-29.9, 30.0-34.9, and >or=35.0 kg/m(2)). Primary outcome was idiopathic PE (medical record confirmed cases of PE not associated with prior surgery, trauma, or malignancy). Secondary analysis of nonidiopathic PE was also performed. Multivariable Cox proportional hazards models were controlled for age, physical activity, caloric intake, smoking, pack-years, race, spouse's educational attainment, parity, menopause, nonaspirin nonsteroidal anti-inflammatory drugs, warfarin, multivitamin supplements, hypertension, coronary heart disease, and rheumatological disease. There were 157 incident idiopathic PE and 338 nonidiopathic PE. There was a strong positive association between BMI, the risk of idiopathic PE (relative risk (RR) = 1.08 (95% confidence interval (CI), 1.06-1.10) per 1 kg/m(2) increase in BMI, P < 0.001) and nonidiopathic PE (RR = 1.08 (95% CI, 1.07-1.10), P < 0.001). The association was linear, and apparent even with modest increases in BMI (22.5-25 kg/m(2)). The risk increased nearly sixfold among subjects with BMI >or=35 kg/m(2), and was present in multiple subgroups. Increasing BMI has a strong, linear association with the development of PE in women. Clinicians should consider BMI when assessing the risk of PE in their patients.

Antihypertensive drugs and risk of venous thromboembolism: results from the EDITH case-control study

Previous studies evaluating the association between arterial blood pressure and venous thromboembolism (VTE) reported conflicting results. The relationship between antihypertensive therapy and VTE has never been specifically evaluated. This report from a hospital-based case-control study included 785 cases with confirmed unprovoked VTE and their 785 age- and sex-matched controls. Cases and controls were asked for drug exposure in a one-to-one standardized interview using the same questionnaire. Drug exposure was defined as current use of drugs at admission with onset at least 1 week ago. Three hundred and eighty-four out of 785 cases (48.9%) and 379 out 785 controls (48.3%) reported that they were currently using at least one antihypertensive drug. Among all antihypertensive therapies, only angiotensin II receptor blockers were significantly associated with a reduced risk for VTE: adjusted conditional odds ratio (OR) 0.45 (95% CI, 0.29-0.70). In this hospital-based case-control study, a preventive role for angiotensin II receptor blockers as regards VTE risk was suggested. More studies are needed in order to further elucidate the biological mechanisms involved.

Serious venous thromboembolism, heterozygous factor V Leiden and prothrombin G20210A mutations in a patient with Klinefelter syndrome and type 2 diabetes

Klinefelter's syndrome (KS) is a common cause of man infertility characterized by small testes, gynecomastia and hypogonadism. Deep vein thrombosis and thomboembolic events are frequent in these patients. Hormone imbalance and co-existent mutations in the coagulation system may be the primary factors in this hypercoagulable state. The increased thromboembolic risk in hypogonadic men has been explained by hypofibrinolysis due to androgen deficiency. Regarding the association between KS and congenital and acquired thrombophilias, to date, only three cases have been. Here, we present the youngest KS case with pulmonary thromboembolism with the heterozygous mutations in factor V Leiden and prothrombin genes, as detected by further tests. He had the previous diagnosis of diabetes mellitus and body mass index was 30 kg/m(2). Our report discusses the prothrombotic state in KS patients, with other possible causes for the young presentation and the importance of necessary tests in emergency service admissions with embolism.