The effects of obesity on venous thromboembolism: A review

The Higher Prevalence of Venous Thromboembolism in the Hungarian Roma Population Could Be Due to Elevated Genetic Risk and Stronger Gene-Environmental Interactions

Background: Interactions between genetic and environmental risk factors (GxE) contribute to an increased risk of venous thromboembolism (VTE). Understanding how these factors interact provides insight for the early identification of at-risk groups within a population and creates an opportunity to apply appropriate preventive and curative measures.

Objective: To estimate and compare GxE for VTE risk in the general Hungarian and Roma populations.

Methods: The study was based on data extracted from a database consisting of results previously obtained from a complex health survey with three pillars (questionnaire-based, physical, and laboratory examinations) involving 406 general Hungarian and 395 Roma subjects. DNA was genotyped for rs121909567 (SERPINC1), rs1799963 (F2), rs2036914 (F11), rs2066865 (FGG), rs6025 (F5), and rs8176719 (ABO) polymorphisms. After allele frequency comparisons, the odds ratio (OR) was calculated for individual SNPs. Furthermore, genetic risk scores (weighted GRS, unweighted GRS) were computed to estimate the joint effect of the genetic factors. Multivariable linear regression analysis was applied to test the impact of GxE on VTE risk after interaction terms were created between genetic and VTE risk factors [diabetes mellitus (DM), cancer, chronic kidney diseases (CKD), coronary artery diseases (CAD), migraine, depression, obesity, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high density lipoprotein (HDL-C), triglyceride (TG), and smoking].

Results: Interestingly, the rs121909567 (SERPINC1, ATBp3 mutation) SNP was not present in the general population at all. However, the risk allele frequency was 1% among the Roma population, which might suggest a founder effect in this minority. This polymorphism multiplicatively interacted with CAD, CKD, cancer, DM, depression, migraine, and obesity. Even though interactions were not statistically significant, the trend of interaction showed the probability of an incremental VTE risk among the Roma population. The risk of VTE was 4.7 times higher (p > 0.05) for Roma subjects who had ≥3 wGRS (median value) compared with individuals having lower wGRS values but lower for the general subjects (OR = 3.1 × 10⁻⁸). Additionally, the risk of VTE was 6.6 times higher in the Roma population that had ≥3 risk alleles (median value) than in individuals with the 0–1 risk allele, and the overall risk was much higher for the Roma population (OR = 6.6; p > 0.05) than for the general Hungarian population (OR = 1.5; p > 0.05). Five positive and significant GxE interactions were identified in the Roma population. The risk of VTE was higher among depressive Roma subjects who carried the risk variant rs2036914 (β = 0.819, p = 0.02); however, this interaction was not significant for the general subjects. The joint presence of high levels of LDL-C and rs2066865 (FGG) increased the VTE risk only among Roma individuals (β = 0.389, p = 0.002). The possibility of VTE risk increment, as a result of a multiplicative interaction between rs8176719 (ABO) and cancer, was identified, which was higher for the Roma population (β = 0.370, p < 0.001) than for the general population (β = −0.042, p = 0.6). The VTE risk increased in the Roma population (β = 0.280, p = 0.001), but was higher in the general population (β = 0.423, p = 0.001) as a result of the multiplicative interaction between CAD and rs2036914 (F11). The presence of a multiplicative interaction between rs2066865 (FGG) and CAD increased the VTE risk for the Roma population (β = 0.143, p = 0.046) but not for the general population (β = −0.329, p < 0.001).

Conclusions: rs121909567 (SERPINC1, ATBp3) was confirmed as a founder mutation in the Roma population. Our study revealed some evidence on the burden of the joint presence of genetic and environmental risk factors on VTE, although the finding is highly subjected to the selection and observational biases due to the very small number of VTE cases and the observational nature of the study design, respectively. As a result of higher genetic load and GxE interactions, this minority Roma population is at higher risk of VTE than the general Hungarian population. Thus, our results suggest the need for an intensive search for the rs121909567 (SERPINC1; ATBp3) founder mutation, which might be an important factor for the assessment of thrombotic disease susceptibility among the Roma population. In addition, we strongly recommend further studies among a large number of VTE cases to explore the more precise impact of genetic and environmental risk factors on VTE in the study populations.

Incidence and Risk Factors for Postoperative Venous Thromboembolic Events in Patients Undergoing Cervical Spine Surgery

STUDY DESIGN

This was a retrospective database study.

OBJECTIVE

The objective of this study was to investigate preoperative risk factors and incidence of venous thromboembolic events (VTEs) after cervical spine surgery.

SUMMARY OF BACKGROUND DATA

VTEs are preventable complications that may occur after spinal procedures. Globally, VTEs account for a major cause of morbidity and mortality. Preoperative risks factors associated with increased VTE incidence after cervical spine surgery have not been well-characterized.

MATERIALS AND METHODS

Patients undergoing anterior cervical discectomy and fusion (ACDF); posterior cervical fusion (PCF); discectomy; and decompression from 2007 to 2017 were identified using the PearlDiver Database. International Classification of Diseases (ICD) Ninth and 10th Revision codes were used to identify VTEs at 1 week, 1 month, and 3 months postoperative as well as preoperative risk factors.

RESULTS

Risk factors with the highest incidence of VTE at 3 months were primary coagulation disorder [ACDF=7.82%, odds ratio (OR)=3.96; decompression=11.24%, OR=3.03], central venous line (ACDF=5.68%, OR=2.11; PCF=12.58%, OR=2.27; decompression=10.17%, OR=2.80) and extremity paralysis (ACDF=6.59%, OR=2.73; PCF=18.80%, OR=2.99; decompression=11.86, OR=3.74). VTE incidence at 3 months for populations with these risks was significant for all surgery types (P<0.001) with the exception of patients with primary coagulation disorder who underwent PCF. Tobacco use had the lowest VTE incidence for all surgery types.

CONCLUSIONS

The total cumulative incidence of VTEs at 3-month follow-up was 3.10%, with the highest incidence of VTEs occurring within the first postoperative week (0.65% at 1 wk, 0.61% at 1 mo, 0.53% at 3 mo for ACDF; 2.56% at 1 wk, 1.93% at 1 mo, 1.45% at 3 mo for PCF; 1.37% at 1 wk, 0.93% at 1 mo, 0.91% at 3 mo for decompression). Several preoperative risk factors were found to be significant predictors for postoperative VTEs and can be used to suggest those at increased risk as well as decrease the incidence of preventable VTEs after cervical spine surgery.

LEVEL OF EVIDENCE

Level III.

Trends of Obese and Morbidly Obese Patients in Same-Day Bilateral Total Knee Arthroplasty from 2009 to 2016

As obesity in the United States increases, the proportion of obese and morbidly obese patients undergoing same-day bilateral total knee arthroplasty (sd-BTKA) remains unknown. Therefore, this study analyzed: (1) incidence, (2) patient demographics, (3) patient course, and (4) patient outcomes in obese and morbidly obese patients undergoing sd-BTKA in the United States from 2009 to 2016. The National Inpatient Sample was queried for all sd-BTKA patients from 2009 to 2016, yielding 39,901 obese and 20,394 morbidly obese patients. Analyzed variables included overall incidence, age, length of stay (LOS), sex, race, payer, Charlson comorbidity index (CCI) status, disposition, complications, location/teaching status, region of hospital, costs, and charges. Categorical variables were evaluated with chi-square analysis, while continuous variables were analyzed by Student's t-tests. Overall, the number of sd-BTKAs decreased over the study period, although the proportion of both obese and morbidly obese patients increased (p < 0.001 for all). The most common CCI status, 3 + , decreased in proportion for both groups (p < 0.001 for all). Hospital costs decreased and charges increased for both groups (p < 0.001 for all). Mean LOS decreased and patients were most commonly discharged to skilled nursing facilities, although these proportions decreased (p < 0.001 for all). Respiratory failures (p < 0.001 for all) increased for both groups, while proportion of deep vein thromboses and hematomas/seromas (p < 0.001 for all) increased for obese patients and proportion of pulmonary emboli (p < 0.001) increased for morbidly obese patients. The results of this study appear to portray improving optimization and patient selection of higher body mass index (BMI) individuals undergoing this procedure. More information is needed comparing the safety of the sd-BTKA across patients of all BMI groups.

Management of Postoperative Complications Following Bariatric and Metabolic Procedures

Bariatric and metabolic surgery is a safe and effective treatment of morbid obesity, a disease that continues to increase in prevalence in the United States and worldwide. The two most commonly performed operations are the sleeve gastrectomy and the gastric bypass. Early and late complications can occur, and although referral to a bariatric surgeon or center is ideal, emergency management of acute problems is relevant to all general surgeons. Bariatric surgery can have surgical and metabolic consequences. An understanding of the altered anatomy and physiology helps to guide management of morbidities. This article discusses surgical postoperative complications and metabolic complications.

Evaluating post-operative venous thromboembolism risk in urology patients using a validated risk assessment model

Background

Venous thromboembolism (VTE) is an important cause of post-surgical morbidity and mortality. This study aimed to apply a validated risk assessment model to evaluate the risk of post-operative VTE in urology patients.

Methods

This prospective descriptive observational study used the Caprini risk assessment model to evaluate VTE risk in patients planned for elective urology surgery at a tertiary Johannesburg hospital from January to June 2020.

Results

Two hundred and twenty-six patients with a mean age of 52 years were evaluated for post-operative VTE risk. The population was generally overweight, with a mean BMI of 26.3 kg/m2. The mean Caprini score was 4.42, reflecting a population at high risk for post-operative VTE. There was no statistically significant difference between males and females in this regard. On average, participants had three risk factors for post-operative VTE. Fifteen per cent of all patients were at low risk for VTE, while 40.3% of participants were categorised as moderate risk. The category with the highest percentage of participants (44.7%) was the high-risk category (Caprini score ≥ 5). High-risk patients undergoing oncology surgery comprised 16.8% of the population, and these patients may require extended duration pharmacological thromboprophylaxis to prevent VTE. The most clinically significant risk factors for post-operative VTE included age, obesity, malignancy and HIV infection.

Conclusion

Venous thromboembolism may be difficult to diagnose, and clinicians may underestimate the risk for it to develop. Risk assessment models, such as the Caprini score, are objective and a practical tool to guide the application of thromboprophylaxis. The application of the Caprini RAM in the elective urological surgery population at Chris Hani Baragwanath Academic Hospital yields similar results to studies performed elsewhere on similar surgical populations. Further research is required to evaluate whether the actual incidence of VTE correlates with the risk assessment in this population. Clinician compliance with the use of RAMs as well as the corresponding recommendations for prophylaxis may need to be evaluated. A validated risk assessment model which accounts for procedure-specific risks in urology may be useful.

An investigation of sickle cell trait, body mass index, and fitness in relation to venous thromboembolism among African American adults

BACKGROUND

The relationships of sickle cell trait (SCT), body mass index (BMI), and physical fitness to venous thromboembolism (VTE) in young adults have received little attention.

OBJECTIVES

To test for associations among SCT, BMI, fitness, and VTE.

PATIENTS/METHODS

We conducted a retrospective cohort study of 48,316 SCT-tested, African American individuals in the US Army during 2011-14. We used Cox proportional hazards models to compute adjusted hazards of deep vein thrombosis (DVT) and pulmonary embolism (PE) associated with selected factors.

RESULTS

Incidence rates of DVT and PE were 1.09 and 0.91 cases per 1000 person-years, respectively. Adjusted hazard ratios (aHRs) for DVT for men and women with SCT were 0.9 (95% confidence interval [CI]: 0.4-2.0; P = .711) and 1.51 (CI: 0.7-3.2; P = .274), respectively. aHRs for PE for SCT+ men and women were 1.1 (CI: 0.5-2.4; P = .773) and 1.2 (CI: 0.5-3.1; P = .650), respectively. Low physical fitness was associated with DVT and PE in women (DVT aHR =3.1; CI: 1.4-6.5; P = .004; PE aHR =4.6; CI: 2.1-9.9; P < .001) and DVT in men (aHR =2.2; CI: 1.0-4.6; P = .048). Recent weight gain of 1 or more BMI points was associated with DVT in men (aHR =1.8; CI: 1.1-2.8; P = .017).

CONCLUSIONS

We found no evidence of increased VTE risk associated with SCT in this population. However, lower fitness levels and BMI increases were so associated.

Successful Treatment of Massive Pulmonary Embolism with Rescue Fibrinolysis in Young Patient with Homocystinemia - Case Report

Pulmonary embolism (PE) is the most frequently missed diagnosis in the urgent clinical department with serious consequences. Patients with unprovoked PE have increased risk of recurrent PE. Approximately 5 to 8% of PE patients have inherited thrombophilias. A solated homocystinemia is a rare cause of unprovoked acute pulmonary embolism. Timely diagnosis and proper treatment can prevent complications, costs and mortality and provide patient better quality of life. We are presenting a 42-year-old woman was admitted to our emergency department with the first episode of severe dyspnea and chest pain. She had no history of previous cardiovascular or respiratory disease and no history of previous pulmonary embolism (PE) or deep vein thrombosis (DVT). Urgent echocardiography showed indirect signs of pulmonary embolism which was confirmed by the pulmonary artery CT angiography performed one day after the patient’s admission. After two days of heparin infusion, she developed a hemodynamic instability with cardiogenic shock and was treated successfully with fibrinolysis. After the clinical stabilization, she was put on the rivaroxaban therapy, which was recommended for additional six months. The thrombophilia profile was done two weeks after stopping the therapy with rivaroxaban. The thrombophilia panel came back positive for high levels of homocysteine (67 μmol/L), with other thrombophilia results within normal limits. The patient was stable during the follow-up period. Pulmonary embolism should be always suspected in younger patients with acute severe dyspnea even without provocable risk factors. High suspicion level and fast diagnosis are lifesaving. In younger patients presented with unprovoked pulmonary embolism, clinicians should consider inherited prothrombotic factors and homocystinemia as a potential cause. Rescue fibrinolysis is a lifesaving therapy in hemodynamic worsening in intermediate high-risk PE patients. A longer anticoagulation therapy should be considered in these cases with novel oral anticoagulants that are recommended as safer and superior therapy.

The effects of anticoagulant therapy re-initiation after gastrointestinal bleeding: A systematic review and meta-analysis

WHAT IS KNOWN AND OBJECTIVE

Long-term anticoagulant/antithrombotic therapy is widely used for the management of thromboembolic conditions. Gastrointestinal bleeding is a common collateral manifestation of anticoagulant/antithrombotic therapy that complicates its administration. The continuation or discontinuation of anticoagulant/antithrombotic therapy after an episode of gastrointestinal bleeding has been a matter of debate. Despite recent positive reports from retrospective cohort studies suggesting a reduction in morbidity- and mortality-related outcomes with continued administration of anticoagulant/antithrombotic agents (even after gastrointestinal bleeding), no consensus or comparisons about the efficacies of continued or discontinued antithrombotic administration exist. Therefore, we developed this current state-of-evidence analysis evaluating the comparative effects of continuation and discontinuation of anticoagulant/antithrombotic drugs after gastrointestinal bleeding on the overall incidences of gastrointestinal bleeding, thromboembolic events and mortality events.

METHODS

We performed a systematic academic literature search according to the PRISMA guidelines across five databases: Web of Science, Embase, CENTRAL, Scopus and MEDLINE. Moreover, we conducted a random effect meta-analysis to compare the effects of continuation and discontinuation of anticoagulant/antithrombotic drugs after an event of gastrointestinal bleeding on the overall incidences of gastrointestinal bleeding, thromboembolic events and mortality events.

RESULTS

We found seven eligible studies (from 1397 candidates) with 2532 participants (mean age, 73.1 ± 4.1 years). Our meta-analysis revealed lower odds of thromboembolic events (OR, -0.21), mortality outcomes (OR, -0.39) and an increase in the incidence of gastrointestinal bleeding (OR, 2.4) in the group with continued anticoagulant/antithrombotic therapy than in the group discontinuing the therapy.

WHAT IS NEW AND CONCLUSION

We provide an updated evidence on the comparative effects between continuation and discontinuation of anticoagulant/antithrombotic drugs after gastrointestinal bleeding events based on the overall incidences of gastrointestinal bleeding, thromboembolic events and mortality events. This study reports confirm an overall lower incidence of thromboembolic events and mortality outcomes for the continuation group than for the discontinuation group.

Weight-adjusted versus fixed dose heparin thromboprophylaxis in hospitalized obese patients: A systematic review and meta-analysis

BACKGROUND

Fixed dose unfractionated or low molecular weight heparin is the recommended treatment for venous thromboembolism (VTE) prevention in hospitalized patients. However, its efficacy has been questioned in obese population. Results of previous studies on weight-adjusted doses of heparin for VTE prevention are contradictory. Different anticoagulant regimens are used in clinical practice, but their role remains to be elucidated.

AIMS

To clarify the efficacy and safety of weight-adjusted dose heparin for VTE prevention in obese subjects hospitalized for medical and surgical conditions.

METHODS

Twelve studies were identified as reporting VTE occurrence, major or minor bleeding and anti-Xa levels. A random-effect meta-analysis was conducted to derive odds ratios (OR) comparing fixed vs weight adjusted-doses heparins on VTE occurrence, bleeding, anti-Xa levels. Medical and surgical patients, prospective vs retrospective and quality of studies were extracted for moderators and meta-regression analysis.

RESULTS

Weight-adjusted dose heparin administration was not associated with reduced VTE occurrence (6320/13317 patients, OR 1.03, 95% C.I. 0.79 to 1.35), nor increased bleeding (5840/10906 patients, OR 0.84, 95% C.I. 0.65 to 1.08), but it was associated with higher anti-Xa levels (284/294 patients, ES 2.04, 95% C.I. 1.16 to 2.92, p<0.0001). A significant heterogeneity was present for comparison of anti-Xa levels (I²=94%, p=0.0001) but not for VTE occurrence or bleeding (I²=7.6% and 12.8% respectivel). None of the moderators explained the heterogeneity of the results among primary studies.

CONCLUSION

Weight-adjusted dose as compared to fixed-dose of heparins in the prevention of VTE in obese patients was not associated with a lower risk of VTE nor a higher risk of bleeding.

Fish oil extracted from Coregonus peled improves obese phenotype and changes gut microbiota in a high-fat diet-induced mouse model of recurrent obesity

Recurrent obesity is rapidly emerging as a public health problem. Previous studies have confirmed that fish oil supplementation can alleviate obesity in mice; however, the effect of fish oil on recurrent obesity remains unclear. In the present study, the modulatory effects of fish oil extracted from Coregonus peled on the phenotypes and gut microbiota of recurrent obese mice were evaluated by MRI, OGTT, and bioinformatics analysis. We found that fish oil supplementation could significantly reduce the body weight gain, net weight gain, body fat distribution, and glucose tolerance. In addition, the composition and structure of gut microbiota were significantly shifted toward those of the control group by fish oil treatment. Moreover, the relative abundance of gut microbiota, such as Bacteroidetes, Bacteroidia, Lachnospiraceae, and Bifidobacterium, was markedly responding to the rapid dietary changes between fish oil and high-fat diet. Overall, our results confirmed that the alleviation of recurrent obesity using fish oil supplementation might be modulated by altering the hysteretic behavior and memory-like function of gut microbiota. We proposed that further studies are needed to elucidate the modulation mechanism.

High prevalence of pulmonary embolism prior to cancer therapies in patients with ovarian and endometrial cancers detected by contrast-enhanced CT using D-dimer as an index

OBJECTIVE

We aimed to evaluate the prevalence of pulmonary embolism (PE) before cancer therapies in patients with ovarian and endometrial cancers with enhanced computed tomography (CT) using D-dimer (DD), and determine the optimal cut-off level of DD.

METHODS

Since 2009, we have performed preoperative venous thromboembolism (VTE) screening of patients with ovarian and endometrial cancer. For patients with DD levels of more than 1.0 μg/ml, enhanced CT images were obtained from the pulmonary apex to the foot to detect PE and deep venous thrombosis (DVT) simultaneously.

RESULTS

Among patients with ovarian cancer, 84 of 413 (20.3%) had VTEs (DVT alone, n = 31 [7.5%]; PE with or without DVT, n = 53 [12.8%]; PE alone, n = 12 [2.9%]). Among patients with endometrial cancer, 50 of 455 (11.0%) had VTEs (DVT alone, n = 19 [4.2%]; PE with or without DVT, n = 31 [6.8%], PE alone, n = 14 [3.1%]). The optimal cut-off level of DD was estimated to be ≥1.5 and ≥1.2 μg/ml in ovarian and endometrial cancers, respectively.

CONCLUSION

Our study revealed a high prevalence of PE before cancer therapies in patients with ovarian and endometrial cancers by enhanced CT using DD.

A Serpin With a Finger in Many PAIs: PAI-1's Central Function in Thromboinflammation and Cardiovascular Disease

Plasminogen activator inhibitor 1 (PAI-1) is a member of the serine protease inhibitor (serpin) superfamily. PAI-1 is the principal inhibitor of the plasminogen activators, tissue plasminogen activator (tPA), and urokinase-type plasminogen activator (uPA). Turbulence in the levels of PAI-1 tilts the balance of the hemostatic system resulting in bleeding or thrombotic complications. Not surprisingly, there is strong evidence that documents the role of PAI-1 in cardiovascular disease. The more recent uncovering of the coalition between the hemostatic and inflammatory pathways has exposed a distinct role for PAI-1. The storm of proinflammatory cytokines liberated during inflammation, including IL-6 and TNF-α, directly influence PAI-1 synthesis and increase circulating levels of this serpin. Consequently, elevated levels of PAI-1 are commonplace during infection and are frequently associated with a hypofibrinolytic state and thrombotic complications. Elevated PAI-1 levels are also a feature of metabolic syndrome, which is defined by a cluster of abnormalities including obesity, type 2 diabetes, hypertension, and elevated triglyceride. Metabolic syndrome is in itself defined as a proinflammatory state associated with elevated levels of cytokines. In addition, insulin has a direct impact on PAI-1 synthesis bridging these pathways. This review describes the key physiological functions of PAI-1 and how these become perturbed during disease processes. We focus on the direct relationship between PAI-1 and inflammation and the repercussion in terms of an ensuing hypofibrinolytic state and thromboembolic complications. Collectively, these observations strengthen the utility of PAI-1 as a viable drug target for the treatment of various diseases.

Cellular fibronectin promotes deep vein thrombosis in diet-induced obese mice

BACKGROUND

Overweight and obesity are significant risk factors for deep vein thrombosis (DVT). Cellular fibronectin containing extra domain A (Fn-EDA), an endogenous ligand for toll-like-receptor 4 (TLR4), contributes to thrombo-inflammation. The role of Fn-EDA in the modulation of DVT is not elucidated yet.

OBJECTIVE

To determine whether Fn-EDA promotes DVT in the context of diet-induced obesity.

METHODS

Wild-type (WT) and Fn-EDA-deficient mice were either fed control or high-fat (HF) diet for 12 weeks. DVT was induced by inferior vena cava (IVC) stenosis and evaluated after 48 hours. Cellular Fn-EDA levels in the plasma of venous thromboembolism (VTE) patients were measured by sandwich ELISA.

RESULTS

We found that cellular Fn-EDA levels were significantly elevated in VTE patients' plasma and positively correlated with body mass index. HF diet-fed WT mice exhibited increased DVT susceptibility compared with control diet-fed WT mice. In contrast, HF diet-fed Fn-EDA-deficient mice exhibited significantly reduced thrombus weight and decreased incidence (%) of DVT compared with HF diet-fed WT mice concomitant with reduced neutrophil content and citrullinated histone H3-positive cells (a marker of NETosis) in IVC thrombus. Exogenous cellular Fn-EDA potentiated NETosis in neutrophils stimulated with thrombin-activated platelets via TLR4. Genetic deletion of TLR4 in Fn-EDA+ mice (constitutively express Fn-EDA in plasma and tissues), but not in Fn-EDA-deficient mice, reduced DVT compared with respective controls.

CONCLUSION

These results demonstrate a previously unknown role of Fn-EDA in the DVT exacerbation, which may be an essential mechanism promoting DVT in the setting of diet-induced obesity.

Interacting hepatic PAI-1/tPA gene regulatory pathways influence impaired fibrinolysis severity in obesity

Fibrinolysis is initiated by tissue-type plasminogen activator (tPA) and inhibited by plasminogen activator inhibitor 1 (PAI-1). In obese humans, plasma PAI-1 and tPA proteins are increased, but PAI-1 dominates, leading to reduced fibrinolysis and thrombosis. To understand tPA–PAI-1 regulation in obesity, we focused on hepatocytes, a functionally important source of tPA and PAI-1 that sense obesity-induced metabolic stress. We showed that obese mice, like humans, had reduced fibrinolysis and increased plasma PAI-1 and tPA, due largely to their increased hepatocyte expression. A decrease in the PAI-1 (SERPINE1) gene corepressor Rev-Erbα increased PAI-1, which then increased the tPA gene PLAT via a PAI-1/LRP1/PKA/p-CREB1 pathway. This pathway was partially counterbalanced by increased DACH1, a PLAT-negative regulator. We focused on the PAI-1/PLAT pathway, which mitigates the reduction in fibrinolysis in obesity. Thus, silencing hepatocyte PAI-1, CREB1, or tPA in obese mice lowered plasma tPA and further impaired fibrinolysis. The PAI-1/PLAT pathway was present in primary human hepatocytes, and associations among PAI-1, tPA, and PLAT in livers from obese and lean humans were consistent with these findings. Knowledge of PAI-1 and tPA regulation in hepatocytes in obesity may suggest therapeutic strategies for improving fibrinolysis and lowering the risk of thrombosis in this setting.

Overall and abdominal obesity in relation to venous thromboembolism

BACKGROUND

Abdominal obesity has been shown to be a superior measure over overall obesity for detecting cardiovascular risk.

OBJECTIVE

We conducted this study to compare the effects of overall and abdominal obesity on venous thromboembolism (VTE) and to calculate population attributable fraction for obesity for VTE.

METHODS

Body mass index (BMI) and waist circumference (WC) were used to represent overall and abdominal obesity, respectively. In the cohort study, we included 74317 Swedish adults with anthropometric measures in 1997 and of whom 4332 were diagnosed with VTE until the end of 2017. A Mendelian randomization study was conducted to investigate causal associations of BMI, WC, and WC adjusted for BMI with VTE using data from FinnGen and UK Biobank study. Population attributable fraction was calculated for overall and abdominal obesity for VTE.

RESULTS

In the cohort study, there were dose-response associations of BMI and WC with VTE. The association between BMI and VTE was attenuated largely after adjusting for WC. Among individuals with normal BMI, participants with substantially increased WC had 53% higher (hazard ratio 1.53; 95% confidence interval, 1.28, 1.81) risk of VTE compared to those with normal WC. The causality of the association of WC adjusted for BMI with VTE was confirmed in Mendelian randomization analysis. The estimated population-attributable risk due to elevated BMI and WC were 12.4% (8.4%, 16.5%) and 23.7% (18.1%, 29.4%), respectively.

CONCLUSIONS

WC might be a preferable indicator linking obesity to VTE. A large proportion of VTE cases can be prevented if the population maintained a healthy BMI and WC.

Individualised Risk Assessments for Recurrent Venous Thromboembolism: New Frontiers in the Era of Direct Oral Anticoagulants

Venous thromboembolism (VTE) is a leading cause of morbidity and mortality and is associated with high recurrence rates. The introduction of direct oral anticoagulants (DOACs) in the 2010s has changed the landscape of VTE management. DOACs have become the preferred anticoagulant therapy for their ease of use, predictable pharmacokinetics, and improved safety profile. Increasingly, guidelines have recommended long term anticoagulation for some indications such as following first unprovoked major VTE, although an objective individualised risk assessment for VTE recurrence remains elusive. The balance of preventing VTE recurrence needs to be weighed against the not insignificant bleeding risk, which is cumulative with prolonged use. Hence, there is a need for an individualised, targeted approach for assessing the risk of VTE recurrence, especially in those patients in whom the balance between benefit and risk of long-term anticoagulation is not clear. Clinical factors alone do not provide the level of discrimination required on an individual level. Laboratory data from global coagulation assays and biomarkers may provide enhanced risk assessment ability and are an active area of research. A review of the prediction models and biomarkers for assessing VTE recurrence risk is provided, with an emphasis on contemporary developments in the era of DOACs and global coagulation assays.

Effectiveness and Safety of Apixaban vs. Warfarin in Venous Thromboembolism Patients with Obesity and Morbid Obesity

This study integrated 5 United States healthcare claims databases to evaluate the risk of recurrent venous thromboembolism (VTE) and major bleeding (MB) among VTE patients who initiated apixaban vs. warfarin, stratified by obesity. Obese and morbidly obese patients were identified based on diagnosis codes. Stabilized inverse probability treatment weighting (IPTW) was conducted to balance observed patient characteristics between treatment cohorts. An interaction analysis was conducted to evaluate treatment effects of apixaban vs. warfarin according to obesity status. Cox proportional hazard models were used to evaluate the risk of recurrent VTE and MB among IPTW weighted obese and morbidly obese patients. A total of 112,024 non-obese patients and 43,095 obese patients were identified, of whom 19,751 were morbidly obese. When stratified by obesity status post-IPTW, no significant interactions were observed for effects of apixaban vs. warfarin on recurrent VTE or MB (interaction p > 0.10). Among IPTW obese and morbidly obese patients, apixaban was associated with a significantly lower risk of recurrent VTE (obese: 0.73 [0.64–0.84]; morbidly obese: 0.65 [0.53–0.80]) and MB (obese: 0.73 [0.62–0.85]; morbidly obese: 0.68 [0.54–0.86]) as compared with warfarin. In this large sample of obese and morbidly obese VTE patients, apixaban had a significantly lower risk of recurrent VTE and MB vs. warfarin.

Neck circumference as reliable predictor of mechanical ventilation support in adult inpatients with COVID-19: A multicentric prospective evaluation

AIMS

COVID-19 is especially severe for elderly subjects with cardiometabolic and respiratory comorbidities. Neck circumference (NC) has been shown to be strongly related to cardiometabolic and respiratory illnesses even after adjustment for body mass index (BMI). We performed a prospective study to investigate the potential of NC to predict the need for invasive mechanical ventilation (IMV) in adult COVID-19 inpatients.

MATERIALS AND METHODS

We prospectively and consecutively enrolled COVID-19 adult patients admitted to dedicated medical wards of two Italian hospitals from 25 March to 7 April 2020. On admission, clinical, biochemical and anthropometric data, including BMI and NC were collected. As primary outcome measure, the maximum respiratory support received was evaluated. Follow-up time was 30 days from hospital admission.

RESULTS

We enrolled 132 subjects (55.0-75.8 years, 32% female). During the study period, 26 (19.7%) patients underwent IMV. In multivariable logistic regression analyses, after adjusting for age, sex, diabetes, hypertension and COPD, NC resulted independently and significantly associated with IMV risk (adjusted OR 1.260-per 1 cm increase 95% CI:1.120-1.417; P < .001), with a stronger association in the subgroup with BMI ≤30 Kg/m² (adjusted OR 1.526; 95% CI:1.243-1.874; P < .001). NC showed a good discrimination power in predicting patients requiring IMV (AUC 0.783; 95% CI:0.684-0.882; P < .001). In particular, NC > 40.5 cm (>37.5 for females and >42.5 for males) showed a higher and earlier IMV risk compared to subjects with lower NC (Log-rank test: P < .001).

CONCLUSIONS

NC is an easy to measure parameter able to predict the need for IMV in adult COVID-19 inpatients.

Systematic duplex ultrasound screening in conventional units for COVID-19 patients with follow-up of 5 days

OBJECTIVE

COVID-19 patients may develop coagulopathy, which is associated with poor prognosis and high risk of thrombosis. The main objective of this work was to evaluate the prevalence of deep venous thrombosis of lower limbs (DVT) through ultrasonography in patients infected with COVID-19 admitted to conventional units at our hospital with 5 days of monitoring. The secondary objective was to determine if D-dimer levels, body mass index, and C-reactive protein were associated with DVT.

METHODS

A total of 72 patients, with a mean age of 65 ± 12.3 years, infected with COVID-19 were admitted to three conventional units at our institution; 28 patients were women. A COVID-19 diagnosis was made by a transcriptase polymerase chain reaction by means of nasopharyngeal swab or by chest computer tomography without iodine contrast media. Demographics, comorbidities, and laboratory parameters were collected. A preventive anticoagulation treatment was established on admission with low-molecular-weight heparin. A complete venous duplex ultrasound (DU) test of lower limbs was performed on day (D) 0 and D5. A pulmonary computer tomography angiogram with iodine contrast media was required when pulmonary embolism was suspected.

RESULTS

On D0, the DU showed acute DVT in seven patients (9.75%). A pulmonary computer tomography angiogram was performed in 12 patients (16.65%), 3 (25%) of whom had an acute pulmonary embolism. On D0, acute DVT was not significantly associated with C-reactive protein (mean 101 ± 98.6 in the group without DVT vs 67.6 ± 58.4 mg/L, P = .43) or body mass index (27.7 ± 5.04 vs 28.1 ± 2.65 kg/m², P = .54). However, we found a significant association between acute DVT and D-dimer levels (1536 ± 2347 vs 9652 ± 10,205 ng/mL, P < .01). Among the patients included on D0, only 32 had a DU on D5. Forty of them (55.55%) were not examined for the following reasons: 7 (9.7%) were previously diagnosed with venous thromboembolism on D0 and therefore were excluded on D5, 8 (11%) were transferred to the intensive care unit, 10 (14%) were discharged from the hospital, 5 (7%) died, and 10 (13.9%) were excluded because of technical issues. On D5, five (15.6%) patients had acute DVT in addition to those found on D0; three were distal and two proximal despite preventive anticoagulation with low-molecular-weight heparin.

CONCLUSIONS

Hospitalized non-intensive care unit patients with COVID-19 pneumonia have a high frequency of venous thrombotic events justifying screening with DU.

Nonalcoholic Fatty Liver Disease-Evidence for a Thrombophilic State?

Nonalcoholic fatty liver disease is the leading cause of liver disease worldwide. It has expansive extrahepatic morbidity and mortality including increased rates of both cardiovascular disease and venous thromboembolism. Derangements in primary, secondary and tertiary hemostasis are found in nonalcoholic fatty liver disease independent of those ascribed to end-stage liver disease. The abnormalities across all stages of hemostasis explain the increased rates of clinically relevant thrombotic events, including pulmonary embolism, deep vein thrombosis and portal vein thrombosis, which on an epidemiologic basis appears to be independent of obesity and other traditional venous thromboembolic risk factors. However, given the complex interaction between obesity, body composition and nonalcoholic fatty liver disease and the potential for exercise to benefit all three, more research is needed to further define the role of each in contributing to the prohemostatic state of nonalcoholic fatty liver disease in order to improve patient oriented outcomes.

Acute popliteal thrombus following total knee arthroplasty: A case report

INTRODUCTION

We report the youngest documented patient (38 years old) to develop an acute popliteal artery thrombus following primary total knee arthroplasty (TKA).

PATIENT CONCERNS

The patient presented for an elective TKA secondary to posttraumatic arthritis. Past medical history included a tibial plateau fracture, two knee arthroscopies and an elevated body mass index (37.53). A right TKA was performed with no intraoperative complications. Two hours postoperatively, the right foot was poikilothermic and lacking dorsalis pedal pulse.

DIAGNOSIS

Popliteal artery thrombus confirmed by angiogram and venous duplex.

INTERVENTIONS

Immediate vascular surgery consult and subsequent embolectomy.

OUTCOMES

At 1 year postoperatively, the patient is doing well with no further complications.

CONCLUSION

Due to the lack of significant past medical history putting this patient at risk, future research should focus on prior trauma, age, and BMI as risk factors, specifically in patients undergoing TKA.

Serum D-dimer should not be used in the diagnosis of venous thromboembolism within 28 days of total knee replacement surgery

Background

Serum D-dimer is frequently used to rule out a diagnosis of venous thromboembolism (VTE), a recognised complication following total knee replacement (TKR). TKR is known to cause a rise in D-dimer levels, reducing its specificity. Previous studies have demonstrated that D-dimer remains elevated within 10 days of TKR and therefore should be avoided. The aim of this study was to determine whether serum D-dimer tests are clinically appropriate in identifying VTE when performed within 28 days of TKR.

Methods

Case notes for patients who had a serum D-dimer test performed for clinically suspected VTE at ≥ 28 days following TKR were retrospectively reviewed for a 6-year period. Demographics, D-dimer result, time after surgery and further radiological investigations were recorded.

Results

Fifty patients underwent D-dimer tests at ≥ 28 days following surgery (median 60 days, range 29–266); 48 of these patients had a positive result. Of these, five had confirmed VTE on radiological investigations. Serum D-dimer was raised in 96% of the patients. Only 10.42% of these patients had confirmed VTE. No patients with negative D-dimers had confirmed VTE.

Conclusions

These findings suggest that serum D-dimer remains raised for at least 28 days and possibly considerably longer following TKR. Serum D-dimer should not be used in patients with clinically suspected VTE within this period because of its unacceptably low specificity of 4.44% and positive predictive value of 10.42%, which can lead to a delay in necessary further radiological investigations, waste of resources and unnecessary exposure to harm.

Trends of venous thromboembolism risk before and after diagnosis of gout: a general population-based study

OBJECTIVE

To estimate the overall risk and the temporal trend of venous thromboembolism (VTE), deep vein thrombosis (DVT), and pulmonary embolism (PE) before and after gout diagnosis in an incident gout cohort compared with the general population.

METHODS

We conducted a matched cohort study using a province-wide population-based administrative health database in Canada. We calculated incidence rates (IRs) and multivariable adjusted hazard ratios (HRs) for the risk of VTE, DVT and PE before and after gout diagnosis.

RESULTS

Among 130 708 incident individuals with gout (64% male, mean age 59 years), 2071 developed VTE, 1377 developed DVT and 1012 developed PE. IRs per 1000 person-years for gout were 2.63, 1.74 and 1.28 compared with 2.03, 1.28 and 1.06 for non-gout, respectively. The fully adjusted HRs (95% CI) for VTE, DVT and PE were 1.22 (1.13, 1.32), 1.28 (1.17, 1.41) and 1.16 (1.05, 1.29). For the pre-gout period, the fully adjusted HRs (95% CI) were 1.51 (1.38, 1.64), 1.55 (1.40, 1.72) and 1.47 (1.31, 1.66) for VTE, DVT and PE. During the third, second and first years preceding gout, the fully adjusted HRs for VTE were 1.44, 1.56 and 1.62. During the first, second, third, fourth and fifth years after gout, the fully adjusted HRs were 1.63, 1.29, 1.33, 1.28 and 1.22. Similar trends were also seen for DVT and PE.

CONCLUSION

Increased risks of VTE, DVT and PE were found both before and after gout diagnosis. The risk increased gradually before gout, peaking in the year prior to diagnosis, and then progressively declined. Gout-associated inflammation may contribute to venous thrombosis risk.

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 factors and impact of portal vein thrombosis in liver transplantation

INTRODUCTION

portal vein thrombosis is a relatively common complication of advanced cirrhosis that increases perioperative risk in liver transplant recipients. This condition was characterized in a cohort of patients, including risk factors and their influence on survival.

MATERIAL AND METHODS

a retrospective study of liver transplant recipients at the Clínica Universidad de Navarra was performed between 2000 and 2015. Differences in clinical and biological characteristics and survival were analyzed in subjects with and without portal vein thrombosis. A predictive index was also developed.

RESULTS

a total of 288 patients were included in the study, portal vein thrombosis was recorded in 46 (16%) cases and seven (15.2%) had stage 3/4 disease according to Yerdel's classification. Factors associated with the presence of esophageal/gastric varices (OR = 3.7; p = 0.03) included variceal ligation or sclerotherapy (OR = 2.3; p = 0.01), being overweight/obesity (OR = 2.1; p = 0.04) and thrombocytopenia (OR = 3.6; p = 0.04). There were no significant differences between the groups with and without portal vein thrombosis in terms of survival according to Kaplan-Meier curve analysis (p = 0.7). However, the mortality rate was higher for Yerdel stages 3-4 (p < 0.01). A predictive index was developed that included varices, body mass index (BMI), thrombocytopenia and activated partial thromboplastin time (APTT). This index had a sensitivity of 76.1% and a specificity of 53.7% for the development of portal thrombosis.

CONCLUSIONS

the presence of esophageal/gastric varices, variceal ligation/sclerotherapy, thrombocytopenia and being overweight/obesity was associated with a higher rate of portal vein thrombosis. Advanced stages had an impact on survival.

New insights on patient-related risk factors for venous thromboembolism in patients with solid organ cancers

Patient-related risk factors for venous thromboembolism (VTE) are infrequently studied. We compared the role of patient-related risk factors for VTE in patients with solid organ cancers to their role in patients without cancer using National Inpatient Sample (NIS) data. Patients with cancer: risk of VTE hospitalization; Increased: chronic pulmonary disease (OR 1.172, 95% CI 1.102-1.247), obesity (OR 1.369, 95% CI 1.244-1.506). Decreased: liver disease (OR 0.654, 95% CI 0.562-0.762), chronic kidney disease (CKD) (OR 0.539, 95% CI 0.491-0.593), end-stage renal disease (ESRD) (OR 0.247, 95% CI 0.187-0.326). Patients without cancer: Risk of VTE hospitalization; Increased: age (OR 1.024, 95% CI 1.022-1.025), congestive heart failure (OR 1.221, 95% CI: 1.107-1.346), chronic pulmonary disease (OR 1.372, 95% CI 1.279-1.473), obesity (OR 2.627, 95% CI 2.431-2.838). Decreased: female gender (OR 0.772, 95% CI 0.730-0.816), diabetes (OR 0.756, 95% CI 0.701-0.815), ESRD (OR 0.315, 95% CI 0.252-0.395). In conclusion, chronic pulmonary disease and obesity increase VTE hospitalization risk in patients with and without cancer and the risk decreases in cancer patients with liver disease, CKD or ESRD.

Weight-Adjusted Contrast Administration in the Computed Tomography Evaluation of Pulmonary Embolism

INTRODUCTION

Computed tomography pulmonary angiogram (CTPA) is widely considered the gold standard for diagnosis of pulmonary embolism (PE) with previous studies demonstrating high sensitivity and specificity. Despite this, nondiagnostic and indeterminate CTPA rates of 5%-26% remain a concern. As part of a continuing quality assurance program, a new weight-adjusted contrast dose and increased administration rate CTPA protocol was studied with an aim to improve diagnostic accuracy of PE evaluation.

METHODS

A total of 2,398 CTPA examinations were reviewed to assess pulmonary arterial enhancement and PE yield in this retrospective study. Between 1 August 2014 and 1 August 2015, 1,133 patients received a fixed-volume (60 mL) contrast dose technique at 4 mL/s (protocol A). A new protocol was then implemented as part of a continuing quality assurance program. Between 15 September 2015 and 15 September 2016, 1,265 patients received a weight-adjusted contrast dose (1 mL/kg) and increased administration rate (5 mL/s) CTPA technique (protocol B). Studies were classed into categories based on quality of study; diagnostic: HU > 211, nondiagnostic: HU < 211 and PE yield; positive, negative, and indeterminate. These variables were compared with cross-sectional surface area to assess the relationship between patient habitus, CTPA diagnostic quality, and PE yield.

RESULTS

A weight-adjusted contrast dose and increased administration rate CTPA protocol (protocol B) resulted in a significant increase in mean PA enhancement (P < .0001), 55.23% decrease in nondiagnostic studies and 43.04% decrease in indeterminate studies. Protocol B demonstrated increased positive and negative CTPA rates with decreased indeterminate rates from 12.38% to 7.04%. Comparison with cross-sectional area demonstrated significant increase in proportion of diagnostic studies and reduction in nondiagnostic and indeterminate CTPAs using protocol B in obese patients.

CONCLUSIONS

A weight-adjusted contrast dose and increased administration rate CTPA protocol can significantly increase PA enhancement, especially in obese patients, resulting in greater high-quality and fewer nondiagnostic and indeterminate CTPA examinations. A CTPA protocol with a higher rate of conclusive examinations can provide greater confidence in PE evaluation for reporting radiologists and accurate clinical decision-making pathways for referring physicians.

Association between obesity and venous thromboembolism

Background and aims

Obesity is associated with numerous pathological conditions, including venous thromboembolism (VTE). VTE is a multifactorial disease; more than half of the hospitalized patients are at risk for VTE.

We aimed to assess the risk of VTE associated with obesity, taking into account the class of obesity (according to the body mass index), gender, age and the intervention of other acquired risk factors.

Methods

A case-control study including 732 patients was designed. Collected data included: age, gender, body mass index, pregnancy/postpartum state, use of hormonal therapy, personal and family history of VTE, smoking, prolonged immobilization and the presence of comorbidities - acquired risk factors for VTE. The risk of VTE was expressed as odds ratio (OR) with 95% confidence interval. Multiple logistic regression analysis was used to detect the independent risk factors. P value <0.05 was considered significant statistic.

Results

Obesity was associated with a 6.2-fold increased risk for VTE. The risk of VTE associated with obesity was highest in patients aged >50 years and in cases included in classes II and III of obesity. The interaction between obesity and another acquired risk factor has almost doubled the risk of VTE. Multivariate logistic regression analysis showed obesity as an independent risk factor for VTE for both female and male patients.

Conclusions

Obesity is an independent and moderate risk factor for VTE. The risk increases with body mass index, age and the presence of other acquired risk factors.

Morbid Obesity and Mortality in Patients With VTE: Findings From Real-Life Clinical Practice

BACKGROUND

The influence of morbid obesity on mortality in patients receiving anticoagulant therapy for VTE has not been consistently evaluated.

METHODS

Data from the RIETE (Registro Informatizado Enfermedad TromboEmbólica) registry were used to compare the mortality risk during anticoagulation in patients with VTE and morbid obesity (BMI ≥ 40 kg/m²) vs those with normal weight (BMI, 18.5-24.9 kg/m²). Patients with or without active cancer were analyzed separately.

RESULTS

By September 2018, there were 1,642 patients with VTE and morbid obesity and 14,848 with normal weight in RIETE. Of these, 245 (5.5%) and 1,397 (11.6%), respectively, had cancer. Median duration of anticoagulant therapy was longer in the morbidly obese patients, with cancer (185 vs 114 days) or without cancer (203 vs 177 days). Among cancer patients, 44 (18.0%) morbidly obese and 1,377 (32.8%) patients with normal weight died during anticoagulation. Among those without cancer, 44 (3.1%) morbidly obese died and 601 (5.6%) with normal weight died. On bivariate analysis, morbid obesity was associated with a lower mortality rate, both in patients with cancer (hazard ratio, 0.34; 95% CI, 0.25-0.45) and in those without cancer (hazard ratio, 0.43; 95% CI, 0.32-0.58). Multivariable analysis confirmed a lower hazard of death in morbidly obese patients with cancer (hazard ratio, 0.68; 95% CI, 0.50-0.94) and without cancer (hazard ratio, 0.67; 95% CI, 0.49-0.96). The risk for VTE recurrences or major bleeding did not differ in patients with or without morbid obesity.

CONCLUSIONS

In patients with VTE, the risk for death during anticoagulation was about one-third lower in morbidly obese patients than in those with normal weight, independently of the presence of cancer.

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

Evaluation of unmet clinical needs in prophylaxis and treatment of venous thromboembolism in at-risk patient groups: pregnancy, elderly and obese patients

BACKGROUND

Venous thromboembolism (VTE) accounts for an estimated 900,000 cases per year in the US alone and constitutes a considerable burden on healthcare systems across the globe.

OBJECTIVE

To understand why the burden is so high, qualitative and quantitative research was carried out to gain insights from experts, guidelines and published studies on the unmet clinical needs and therapeutic strategies in VTE prevention and treatment in three populations identified as being at increased risk of VTE and in whom VTE prevention and treatment were regarded as suboptimal: pregnant women, the elderly and obese patients.

METHODOLOGY

A gap analysis methodology was created to highlight unmet needs in VTE management and to discover the patient populations considered most at risk. A questionnaire was devised to guide qualitative interviews with 44 thrombosis and haemostasis experts, and a review of the literature on VTE in the specific patient groups from 2015 to 2017 was completed. This was followed by a Think Tank meeting where the results from the research were discussed.

RESULTS

This review highlights the insights gained and examines in detail the unmet needs with regard to VTE risk-assessment tools, biomarkers, patient stratification methods, and anticoagulant and dosing regimens in pregnant women, the elderly and obese patients.

CONCLUSIONS

Specifically, in pregnant women at high risk of VTE, low-molecular-weight heparin (LMWH) is the therapy of choice, but it remains unclear how to use anticoagulants when VTE risk is intermediate. In elderly patients, evaluation of the benefit of VTE prophylaxis against the bleeding risk is particularly important, and a head-to-head comparison of efficacy and safety of LMWH versus direct oral anticoagulants is needed. Finally, in obese patients, lack of guidance on anticoagulant dose adjustment to body weight has emerged as a major obstacle in effective prophylaxis and treatment of VTE.

Acute Deep Venous Thrombosis and Pulmonary Embolism in Foot and Ankle Trauma in the National Trauma Data Bank: An Update and Reanalysis

The data regarding rates of deep venous thrombosis and pulmonary embolism after foot and ankle trauma remain sparse. In this study of the National Trauma Data Bank Data set (2007-2009 and 2010-2016), these rates were reexamined and risk factors associated with these complications were assessed. Data quality is improved in the later data set; the incidence of deep venous thrombosis and pulmonary embolism was 0.28% and 0.21%, respectively, in the 2010-2016 data. Prophylaxis, male gender, treatment in a university hospital, open reduction, chronic obstructive pulmonary disease, and hypertension were notable significant risk factors for pulmonary embolism. For deep venous thrombosis, male gender, bleeding disorder, angina, and prophylaxis were risk factors. Careful, individualized assessment of the risk factors associated with deep venous thrombosis and pulmonary embolism is important, and the merits of routine prophylaxis remain in question.

Survival Benefit of Obese Patients With Pulmonary Embolism

OBJECTIVE

To investigate the impact of obesity and underweight on adverse in-hospital outcomes in pulmonary embolism (PE).

PATIENTS AND METHODS

Patients diagnosed as having PE based on International Statistical Classification of Diseases and Related Health Problems, 10th Revision, German Modification code I26 in the German nationwide inpatient database were stratified for obesity, underweight, and normal weight/overweight (reference group) and compared regarding adverse in-hospital outcomes.

RESULTS

From January 1, 2011, through December 31, 2014, 345,831 inpatients (53.3% females) 18 years and older were included in this analysis; 8.6% were obese and 0.5% were underweight. Obese patients were younger (67.0 vs 73.0 years), were more frequently female (60.2% vs 52.7%), had a lower cancer rate (13.6% vs 20.5%), and were more often treated with systemic thrombolysis (6.4% vs 4.3%) and surgical embolectomy (0.3% vs 0.1%) vs the reference group (P<.001 for all). Overall, 51,226 patients (14.8%) died during in-hospital stay. Obese patients had lower mortality (10.9% vs 15.2%; P<.001) vs the reference group and a reduced odds ratio (OR) for in-hospital mortality (OR, 0.74; 95% CI, 0.71-0.77; P<.001) independent of age, sex, comorbidities, and reperfusion therapies. This survival benefit of obese patients was more pronounced in obesity classes I (OR, 0.56; 95% CI, 0.52-0.60; P<.001) and II (OR, 0.63; 95% CI 0.58-0.69; P<.001). Underweight patients had higher prevalence of cancer and higher mortality rates (OR, 1.15; 95% CI, 1.00-1.31; P=.04).

CONCLUSION

Obesity is associated with decreased in-hospital mortality rates in patients with PE. Although obese patients were more often treated with reperfusion therapies, the survival benefit of obese patients occurred independently of age, sex, comorbidities, and reperfusion treatment.

Multi-Objective Optimization for Personalized Prediction of Venous Thromboembolism in Ovarian Cancer Patients

Thrombotic events are one of the leading causes of mortality and morbidity related to cancer, with ovarian cancer having one of the highest incidence rates. The need to prevent these events through the prescription of adequate schemes of antithrombotic prophylaxis has motivated the development of models that aid the identification of patients at higher risk of thrombotic events with lethal consequences. However, antithrombotic prophylaxis increases the risk of bleeding and this risk depends on the class and intensity of the chosen antithrombotic prophylactic scheme, the clinical and personal condition of the patient and the disease characteristics. Moreover, the datasets used to obtain current models are imbalanced, i.e., they incorporate more patients who did not suffer thrombotic events than patients who experienced them what can lead to wrong predictions, especially for the clinically relevant patient group at high risk of thrombosis. Herein, predictive models based on machine learning were developed utilizing 121 high-grade serous ovarian carcinoma patients, considering the clinical variables of the patients and those typical of the disease. To properly manage the data imbalance, cost-sensitive classification together with multi-objective optimization was performed considering different combinations of metrics. In this way, five Pareto fronts and a series of optimal models with different false positive and false negative rates were obtained. With this novel approach to the development of clinical predictive models, personalized models can be developed, helping the clinician to achieve a better balance between the risk of bleeding and the risk of thrombosis.

Evaluating Time to In-Hospital Venous Thromboembolism in Obese Patients

BACKGROUND

Currently, no consensus approach exists for optimal venous thromboembolism (VTE) prophylaxis in obese (BMI ≥30 kg/m²) patients. Time to development of in-hospital VTE is not well studied.

OBJECTIVE

This study evaluates time to in-hospital VTE in obese patients.

METHODS

A single-center, retrospective study evaluated obese patients that developed an in-hospital VTE. Patients were categorized into 3 BMI groups: 30 to 34.9 (group 1), 35 to 39.9 (group 2), and ≥40 (group 3) kg/m². The primary end point compared time to VTE between the groups.

RESULTS

A total of 246 patients were included, and time to VTE was similar between the groups, 8 (group 1) versus 8 (group 2) versus 9 days (group 3); P = .38. Secondary outcomes showed time to VTE was shorter in acute care versus ICU patients (7.5 vs 10 days; P = .01), nonsurgical versus surgical patients (6 vs 9 days; P = .004), and no prophylaxis versus mechanical plus pharmacologic prophylaxis (4.5 vs 9 days; P < .001).

CONCLUSIONS

BMI category did not significantly impact time to in-hospital VTE. This study provides insight into the timing of in-hospital VTE in obese patients. The differences in prophylactic strategies highlight the importance of optimized prophylaxis.

Efficacy of the 1-year (13-cycle) segesterone acetate and ethinylestradiol contraceptive vaginal system: results of two multicentre, open-label, single-arm, phase 3 trials

Background

A ring-shaped, contraceptive vaginal system designed to last 1 year (13 cycles) delivers an average of 0·15 mg segesterone acetate and 0·013 mg ethinylestradiol per day. We evaluated the efficacy of this contraceptive vaginal system and return to menses or pregnancy after use.

Methods

In two identically designed, multicentre, open-label, single-arm, phase 3 trials (one at 15 US academic and community sites and one at 12 US and international academic and community sites), participants followed a 21-days-in, 7-days-out segesterone acetate and ethinylestradiol contraceptive vaginal system schedule for up to 13 cycles. Participants were healthy, sexually active, non-pregnant, non-sterilised women aged 18–40 years. Women were cautioned that any removals during the 21 days of cyclic use should not exceed 2 h, and used daily paper diaries to record vaginal system use. Consistent with regulatory requirements for contraceptives, we calculated the Pearl Index for women aged 35 years and younger, excluding adjunctive contraception cycles, as the primary efficacy outcome measure. We also did intention-to-treat Kaplan-Meier life table analyses and followed up women who did not use hormonal contraceptives or desired pregnancy after study completion for 6 months for return to menses or pregnancy. The trials are registered with ClinicalTrials.gov, numbers NCT00455156 and NCT00263341.

Findings

Between Dec 19, 2006, and Oct 9, 2009, at the 15 US sites, and between Nov 1, 2006, and July 2, 2009, at the 12 US and international sites we enrolled 2278 women. Our overall efficacy analysis included 2265 participants (1130 in the US study and 1135 in the international study) and 1303 (57·5%) participants completed up to 13 cycles. The Pearl Index for the primary efficacy group was 2·98 (95% CI 2·13–4·06) per 100 woman-years, and was well within the range indicative of efficacy for a contraceptive under a woman's control. The Kaplan-Meier analysis revealed the contraceptive vaginal system was 97·5% effective, which provided further evidence of efficacy. Pregnancy occurrence was similar across cycles. All 290 follow-up participants reported return to menses or became pregnant (24 [63%] of 38 women who desired pregnancy) within 6 months.

Interpretation

The segesterone acetate and ethinylestradiol contraceptive vaginal system is an effective contraceptive for 13 consecutive cycles of use. This new product adds to the contraceptive method mix and the 1-year duration of use means that women do not need to return to the clinic or pharmacy for refills every few months.

Funding

Eunice Kennedy Shriver National Institute of Child Health and Human Development of the National Institutes of Health, the US Agency for International Development, and the WHO Reproductive Health Research Department.

A ten-year retrospective study investigating the rate of venous thromboembolism in patients who require immobilization in a total contact lower limb cast

Aims

To our knowledge, there is currently no information available about the rate of venous thromboembolism (VTE) or recommendations regarding chemoprophylaxis for patients whose lower limb is immobilized in a plaster cast. We report a retrospective case series assessing the rate of symptomatic VTE in patients treated with a lower limb cast. Given the complex, heterogeneous nature of this group of patients, with many risk factors for VTE, we hypothesized that the rate of VTE would be higher than in the general population.

Patients and Methods

Patients treated with a lower limb cast between 2006 and 2018 were identified using plaster room records. Their electronic records and radiological reports were reviewed for details about their cast, past medical history, and any VTE recorded in our hospital within a year of casting.

Results

There were 136 episodes of casting in 100 patients. The mean age was 55 years (22 to 91). The mean time in a cast was 45 days (five days to eight months). A total of 76 patients had neuropathy secondary to diabetes. No patient received chemical thromboprophylaxis while in a cast. One VTE (0.7% of casting episodes) was documented. This was confirmed by Doppler scan nine days after removing the cast.

Conclusion

The frequency of VTE was higher than that of the general population (0.05%); this is most likely attributable to our patients’ apparent increase in VTE risk as suggested by The National Institute for Health and Care Excellence (NICE). These findings suggest that thromboprophylaxis is not routinely indicated in patients who undergo immobilization of the lower limb in a cast, although the risks of VTE should be assessed. While the cast itself does not pose an increased risk, other pathologies, such as active cancer, mean that each individual case needs to be considered on their merit. Cite this article: Bone Joint J 2019;101-B:691–694.

Prevalence and Characteristics of Venous Thrombosis after Catheter Ablation of Atrial Fibrillation in Patients Receiving Periprocedural Direct Oral Anticoagulants

Background

Periprocedural venous thromboembolisms (VTEs) area rare occurrence but a critical complication after catheter ablation of atrial fibrillation (AF).The aim of this study was to investigate the incidence of symptomatic deep vein thromboses (DVTs) and pulmonary thromboembolisms (PTEs) in patients who underwent AF catheter ablation and received periprocedural oral anticoagulation with direct oral anticoagulants (DOACs).

Methods and Results

A total of 2,193 consecutive patients undergoing AF catheter ablation with periprocedural DOACs were retrospectively analyzed.Two patients (0.091%) experienced symptomatic DVTs after the ablation, and no patients had any PTEs. One patient was a 72-year-old female who underwent cryoballoon ablation with periprocedural apixaban at a dose of 2.5 mg twice daily. The other patient was a 74-year-old male who underwent a Hot Balloon ablation and thereafter radiofrequency catheter ablation for recurrent AF with edoxaban at30 mg once daily. Both DVT patients underwent AF ablation by the right femoral vein approach, and after discharge had right leg pain and swelling on post-procedural days 4 and 8, respectively. TheDVT was treated by increasing the dose of apixaban and changing it from 30 mg/day of edoxaban to 15-30 mg/day of rivaroxaban, and the thrombi completely disappeared in both patients without any thromboembolic and hemorrhagic complications.

Conclusions

AF catheter ablation with periprocedural DOAC treatment revealed anextremely low incidence of symptomatic VTEs, which may be successfully treated by increasing the DOAC dose or changing the DOAC type.

The relative roles of maternal survival and inter-personal violence as selection pressures on the persistence of Neanderthal hypercoagulability alleles in modern Europeans

Background: Simonti et al. reported variation in the frequency of Neanderthal alleles found in modern humans and argued that they may have provided an evolutionary advantage. One such allele is SNP rs3917862, associated with hypercoagulability. rs3917862 can be deleterious, but can also help prevent blood loss. Aim: To investigate two possible selective pressure hypotheses for rs3917862 surviving to higher frequencies: deaths from interpersonal violent trauma and childbirth. Subjects and methods: Mortality data from modern hunter-gatherers models the living conditions and causes of death of humans and Neanderthals at the point of admixture. Results: National census data indicates a positive correlation between the presence of rs3917862 and decreased maternal mortality ratios. When the maternal mortality ratio is modelled using GDP, births attended by skilled assistants and the presence of rs3917862, women are 0.1% more likely to die in childbirth in populations lacking rs3917862. Deaths due to violence show no correlation with rs3917862. Conclusion: These findings challenge the idea that Neanderthal admixture has negatively impacted the overall health of modern humans. Maternal survival may have acted as a selective pressure for the persistence of hypercoagulability alleles in modern Europeans. Understanding the role of hypercoagulability in childbirth, and the role of rs3917862, could help to reduce maternal mortality ratios.

A Review on Role of Microbiome in Obesity and Antiobesity Properties of Probiotic Supplements

Probiotics are now recognized for several health benefits and they have been recommended as a complementary therapeutic agent for metabolic disorders. Obesity is an altered health condition, which is a resultant of irregular energy intake and energy balance, changes in gut microbiota, and improper diet with the influence of genetic makeup and environmental factors. Several studies revealed the influence of probiotic supplementation on obesity-associated consequences in vitro, in vivo, and in human clinical studies. The current manuscript discussed the factors influencing the occurrence of obesity, the interplay between microbiome and obesity, the effect of the probiotic intervention on the health status of obese people, and possible mechanism of antiobesity activity of probiotics. The literature survey revealed that the antiobese activity of probiotics might be associated with their ability to alter the intestinal microbiota, remodeling of energy metabolism, alter the expression of genes related to thermogenesis, glucose metabolism, and lipid metabolism, and change the parasympathetic nerve activity. Further intense research is necessary to figure out the best probiotic or synbiotic mixture and optimum dosage and duration of the intervention to reduce obesity and prevent the recurring of obese condition.

Individual risk factors predictive of venous thromboembolism in patients with temporary lower limb immobilization due to injury: a systematic review

Essentials Thromboprophylaxis after lower limb injury is often based on complex risk stratification. Our systematic review identified variables predicting venous thromboembolism (VTE) in this group. Age and injury type were commonly reported to increase the odds of VTE (odds ratio 1.5-3.48). We found limited evidence to support the use of other risk factors within prediction models. SUMMARY: Background Patients immobilized after lower limb injury are at risk of venous thromboembolism (VTE). There is international variation in the use of thromboprophylaxis for such patients. Risk-based strategies have been adopted to aid decision making in many settings. The accuracy of these strategies is unclear. Objectives A systematic review was undertaken to identify all individual patient-identifiable risk factors linked to any VTE outcome following lower limb immobilization. Methods Several electronic databases were searched from inception to May 2017. Any studies that included a measurement of VTE as a patient outcome in adults requiring temporary immobilization (e.g. leg cast or brace in an ambulatory setting) for an isolated lower limb injury and reported risk factor variables were included. Descriptive statistics and thematic analysis were used to synthesize the evidence. Results Our database search returned 4771 citations, of which 15 studies reporting outcome data on 80 678 patients were eligible for analysis. Risk-factor associations were reported through regression analyses, non-parametric tests and descriptive statistics. All studies were assessed as at moderate or serious risk of bias using the ROBINS-I risk of bias tool. Advancing age and injury type were the only individual risk factors demonstrating a reproducible association with increased symptomatic and/or asymptomatic VTE rates. Several risk factors currently used in scoring tools did not appear to be robustly evaluated for subsequent association with VTE within these studies. Conclusions Clinicians should be aware of the limited evidence to support individual risk factors in guiding thromboprophylaxis use for this patient cohort.

Obstructive sleep apnoea and venous thromboembolism: pathophysiological links and clinical implications

Obstructive sleep apnoea (OSA) and pulmonary embolism (PE) remain major health issues worldwide. Data from pathophysiological studies suggest that both intermittent hypoxia and sleep fragmentation are associated with increased blood coagulability, endothelial dysfunction and venous stasis. There is growing evidence that OSA is potentially prevalent in and a risk factor for PE. Conversely, patients with acute PE have two to four times greater risk of moderate-to-severe OSA. The role of continuous positive airway pressure (CPAP) treatment in improving clinically meaningful outcomes in PE patients remains unclear, although some authors have suggested that CPAP could improve the hypercoagulability state and normalise circadian alterations in some of the coagulation molecules, as observed in patients with OSA. Emerging research highlights the complex interdependent relationships between OSA and PE, emphasising the need for rigorous, well-powered trials that address the impact of OSA and its treatment on the prevention and management of PE. Undoubtedly, these will require closer collaboration between the sleep medicine and clinical/venous thromboembolism communities.

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.

Genetic effects of BDKRB2 and KNG1 on deep venous thrombosis after orthopedic surgery and the potential mediator

Deep venous thrombosis (DVT) is a common complication of orthopedic surgery. Genetic risk factors and high heritability carried a substantial risk of DVT. In this study, we aimed to investigate the potential association in the Han Chinese population between the polymorphisms of BDKRB2 and KNG1 and DVT after orthopedic surgery (DVTAOS). A total of 3,010 study subjects comprising 892 DVT cases and 2,118 controls were included in the study, and 39 single nucleotide polymorphisms (SNPs) in total (30 for BDKRB2 and 9 for KNG1) were chosen for genotyping. Two SNPs, rs710446 (OR = 1.27, P = 0.00016) and rs2069588 (OR = 1.29, P = 0.00056), were identified as significantly associated with DVTAOS. After adjusting for BMI, the significance of rs2069588 decreased (P = 0.0013). Haplotype analyses showed that an LD block containing rs2069588 significantly correlated with the DVTAOS risk. Moreover, bioinformatics analysis indicated that hsa-miR-758-5p and BDKRB2 formed miRNA/SNP target duplexes if the rs2069588 allele was in the T form, suggesting that rs2069588 may alter BDKRB2 expression by affecting hsa-miR-758-5p/single-nucleotide polymorphism target duplexes. Our results demonstrate additional evidence supporting that there is an important role for the KNG1 and BDKRB2 genes in the increased susceptibility of DVTAOS.

A systematic review-meta-analysis of venous thromboembolic events following primary hip arthroscopy for FAI: clinical and epidemiologic considerations

The purpose of this study was to report the proportion of venous thromboembolic events (VTE) in patients undergoing primary hip arthroscopy for femoroacetabular impingement (FAI) and present a critical overview of the literature to aid in better result interpretation. MedLine, Scopus and Web of Science databases were searched from January 2000 to March 2017. Four thousand-five-hundred and seventy-seven hip cases were included in the meta-analysis of 38 studies. The mean age of patients was 36 ± 1.8 years and the mean follow-up time was 20.6 months. The meta-analysed rate of deep vein thrombosis (DVT) in patients undergoing primary hip arthroscopy for FAI syndrome was 1.18%; 95%CI [0.8–1.74%]; The meta-analysed rate of pulmonary embolism (PE) in patients undergoing primary hip arthroscopy for FAI syndrome was 0.59%; 95%CI [0.38–0.92%]. Quality assessment was performed using the Methodological Index for Non-Randomized Studies (MINORS) criteria the Quality in Prognostic Studies (QUIPS) tool. Sensitivity analysis was conducted to assess for publication bias and its influence on the results. The corrected for publication bias proportion of DVT was 2.02%; 95%CI [1.36–2.99%]. The DVT rate was double following the correction of bias while additional types of bias were detected. Attention must be paid when considering the outcomes of observational studies to make clinical decisions. Insufficient evidence exists to support whether anti-VTE chemoprophylaxis should be administered to patients undergoing primary hip arthroscopy for FAI. Due to the life-threatening character of this complication, the results should serve as starting point to design clinical trials and establish guidelines. Until then, the application of preventive measures against VTE should be decided on a case-by-case basis.

Venous thromboembolism, factor VIII and chronic kidney disease

Chronic kidney disease (CKD) affects 30 million Americans and is associated with approximately a two-fold increased risk of venous thromboembolism (VTE). There is a graded increased risk of VTE across declining kidney function, as measured by estimated glomerular filtration rate (eGFR) and albuminuria. When patients with end-stage kidney disease (ESKD) experience VTE they are more likely than the general population to be hospitalized and they have a higher mortality. The incidence and consequences of VTE may also differ depending on the cause of kidney disease. In addition, kidney transplant patients with VTE are at a greater risk for death and graft loss than transplant patients without VTE. The reasons that patients with CKD are at increased risk of VTE are not well understood, but recent data suggest that factor VIII is a mediator. Factor VIII is an essential cofactor in the coagulation cascade and a strong risk factor for VTE in general. It is inversely correlated with eGFR and prospective studies demonstrate that factor VIII activity predicts incident CKD and rapid eGFR decline. The etiology of CKD may also influence factor VIII levels. This review summarizes the epidemiology VTE in CKD and reviews the biochemistry of factor VIII and determinants of its levels, including von Willebrand factor and ABO blood group. We explore mechanisms by which the complications of CKD might give rise to higher factor VIII and suggests future research directions to understand how factor VIII and CKD are linked.