Is Venous Thromboembolism Prophylaxis Needed in Patients Undergoing Knee Arthroscopy? A Prospective Observational Study.

BACKGROUND: Although rare, deep vein thrombosis is a potentially life-threatening complication of knee arthroscopy. There are scanty literature analysing deep vein thrombosis after arthroscopy in Nepal. This study aimed to identify the prevalence of deep vein thrombosis in patients undergoing knee arthroscopy without chemoprophylaxis postoperatively at 2 weeks and 6 weeks, respectively. The study also aimed to estimate the risk of deep vein thrombosis in these patients by using Caprini Risk Assessment Model. METHODS: This prospective observational study was conducted at AKB center, B and B Hospital, Gwarko, Lalitpur, over a period of 16 months. All patients who underwent arthroscopy knee surgeries fulfilling the inclusion criteria were included in the study. The primary outcome measure was the prevalence of deep vein thrombosis as diagnosed by compression color-coded ultrasonography of the popliteal vein and calf vein at 2 weeks and 6 weeks postoperatively. The secondary outcome measure was the prevalence of deep vein thrombosis in the risk groups according to Caprini Risk Assessment Model. RESULTS: Out of 612 patients who underwent arthroscopic knee surgeries during the study period, 2 patients (0.33%) developed deep vein thrombosis at 6 weeks follow-up as diagnosed with ultrasonography of the popliteal and calf veins. The prevalence rate in high-risk group was 0.33% (1 in 307) and in very high-risk group was 5.88% (1 in 17). CONCLUSIONS: There was a low prevalence of deep vein thrombosis without chemoprophylaxis following knee arthroscopy in our study. There was higher prevalence of deep vein thrombosis in very high-risk group patients, so close monitoring of such patients during follow-up is recommended.

The plasma miRNome and venous thromboembolism in high-grade glioma: miRNA Sequencing of a nested case-control cohort.

Patients with high-grade gliomas are at high risk of venous thromboembolism (VTE). MicroRNAs (miRNAs) are small non-coding RNAs with multiple roles in tumour biology, haemostasis and platelet function. Their association with VTE risk in high-grade glioma has not been comprehensively mapped so far. We thus conducted a nested case-control study within 152 patients with WHO grade IV glioma that had been part of a prospective cohort study on VTE risk factors. At inclusion a single blood draw was taken, and patients were thereafter followed for a maximum of 2 years. During that time, 24 patients (16%) developed VTE. Of the other 128 patients, we randomly selected 24 age- and sex-matched controls. After quality control, the final group size was 21 patients with VTE during follow-up and 23 without VTE. Small RNA next-generation sequencing of plasma was performed. We observed that hsa-miR-451a was globally the most abundant miRNA. Notably, 51% of all miRNAs showed a correlation with platelet count. The analysis of miRNAs differentially regulated in VTE patients-with and without platelet adjustment-identified potential VTE biomarker candidates such as has-miR-221-3p. Therewith, we here provide one of the largest and deepest peripheral blood miRNA datasets of high-grade glioma patients so far, in which we identified first VTE biomarker candidates that can serve as the starting point for future research.

Association of the neutrophil-to-lymphocyte ratio with the occurrence of venous thromboembolism and arterial thrombosis.

OBJECTIVE: This study aimed to assess the association of the neutrophil-to-lymphocyte ratio (NLR) with the occurrence of venous thromboembolism (VTE) and arterial thrombosis (AT). METHODS: This was a retrospective cross-sectional study including 585 medical records obtained from all consecutive patients who were suspected of having thrombosis. RESULTS: The AT group had a higher neutrophil count and NLR and a lower lymphocyte count than the non-thrombosis group. Receiver operating characteristic curve analysis showed the ability of the NLR to predict the presence of AT. The cut-off value for the NLR was 4.44. No distinction was found in the NLR between the VTE and non-thrombosis groups. Regression analysis showed that a high NLR was an independent factor related to the presence of AT. Patients with an NLR ≥ 4.44 had a higher risk of AT than those with an NLR < 4.44 (odds ratio = 2.015, 95% confidence interval: 1.180-3.443). CONCLUSION: A high NLR may be considered a predictive factor for the occurrence of AT, but an association with the presence of VTE was not found.

Successful management of VTE with essential thrombocythemia and cavernous transformation of the portal vein in early pregnancy: a case report.

Due to the thrombohemorrhagic potential of essential thrombocythemia, pregnancy complicated by essential thrombocythemia should be recognized as a risk factor for obstetric complications. Here, we report the case of a patient with essential thrombocythemia with two significantly different pregnancy outcomes. Her first pregnancy (at 30 years of age) ended with an uneventful term delivery. However, the patient progressed to cavernous transformation of the portal vein in the period between her two pregnancies and subsequently experienced deep venous thrombosis during the first trimester of her second pregnancy (at 36 years of age). The patient's platelet count during pregnancy was within the normal range, so she ignored previous instances of essential thrombocytosis (at 26 years of age). The patient's main symptom was unrelieved pain in her leg. After that, she was successfully treated with anticoagulant throughout her entire pregnancy, resulting in a term vaginal delivery. This case highlights the importance of assessing pregnant patients with essential thrombocythemia according to their risk stratification. Specifically, risk assessments for potential pregnancy complications should take into account advanced maternal age and a previous history of thrombosis. Patients with essential thrombocythemia should be encouraged to participate in preconception counseling for risk assessment and to initiate prophylactic anticoagulation as soon as possible.

Serum albumin and cardiovascular disease: a Mendelian randomization study.

BACKGROUND: An increasing body of evidence suggests that serum albumin levels play a role in cardiovascular diseases. However, the specific causal relationship between serum albumin levels and cardiovascular disease remains partially unknown. METHODS: Mendelian randomization (MR) was employed in this study to examine potential causal relationships between instrumental variables and cardiovascular diseases. Specifically, we utilized genetic variants of serum albumin levels within the reference range as our instrumental variables. To acquire data on genetic associations with cardiovascular diseases, we sourced information from renowned genome-wide association studies such as UK BioBank, EMBL-EBI, and FinnGen. Notably, our study leveraged summary statistics from large cohorts that have been previously described. RESULTS: We explored the association between serum albumin levels and various conditions, including heart failure (HF), venous thromboembolism (VTE), stroke, atrial fibrillation (AF), coronary artery disease (CAD), type 2 diabetes (T2DM), and pulmonary heart disease (PHD). Genetically predicted serum albumin levels were associated with PHD (odds ratio = 0.737, 95% CI = 0.622 - 0.874, P < 0.001), AF (odds ratio = 0.922, 95% CI = 0.870 - 0.977, P = 0.006), VTE (odds ratio = 0.993, 95% CI = 0.991 - 0.995, P < 0.001), and Stroke (odds ratio = 0.997, 95% CI = 0.995 - 0.999, P = 0.002). However, genetically predicted serum albumin level traits were not associated with HF, CAD and T2DM. CONCLUSION: Our study demonstrates a significant association between serum albumin levels and cardiovascular disease, underscoring the crucial role of low serum albumin as a predictive factor in patients with cardiovascular disease.

Venous thromboembolism chemical prophylaxis after skull base surgery.

PURPOSE: There is no guidance surrounding postoperative venous thromboembolism (VTE) prophylaxis using pharmacological agents (chemoprophylaxis) in patients undergoing skull base surgery. The aim of this study was to compare VTE and intracranial haematoma rates after skull base surgery in patients treated with/without chemoprophylaxis. METHODS: Review of prospective quaternary centre database including adults undergoing first-time skull base surgery (2009-2020). VTE was defined as deep vein thrombosis (DVT) and pulmonary embolism (PE) within 6 months of surgery. Multivariate logistic regression was used to determine factors predictive of postoperative intracranial haematoma/VTE. Propensity score matching (PSM) was used in group comparisons. RESULTS: One thousand five hundred fifty-one patients were included with a median age of 52 years (range 16-89 years) and female predominance (62%). Postoperative chemoprophylaxis was used in 81% of patients at a median of 1 day postoperatively. There were 12 VTE events (1.2%), and the use of chemoprophylaxis did not negate the risk of VTE entirely (p > 0.99) and was highest on/after postoperative day 6 (9/12 VTE events). There were 18 intracranial haematomas (0.8%), and after PSM, chemoprophylaxis did not significantly increase the risk of an intracranial haematoma (p > 0.99). Patients administered chemoprophylaxis from postoperative days 1 and 2 had similar rates of intracranial haematomas (p = 0.60) and VTE (p = 0.60), affirmed in PSM. CONCLUSION: Postoperative chemoprophylaxis represents a relatively safe strategy in patients undergoing skull base surgery. We advocate a personalised approach to chemoprophylaxis and recommend it on postoperative days 1 or 2 when indicated.

Biomarkers Profile in Provoked Versus Unprovoked Deep Venous Thrombosis.

Venous thromboembolism (VTE), including deep venous thrombosis (DVT) and pulmonary embolism (PE), represents a substantial healthcare challenge. Provoked and unprovoked DVT cases carry distinct risks and treatment considerations. Recognizing the limitations of this classification, molecular markers may enhance diagnostic precision and guide anticoagulation therapy duration relying on patient history and risk factors. This preliminary, open-label, prospective cohort study was conducted including 15 patients (10 provoked DVT and 5 unprovoked DVT) and a control group of healthy plasmatic subjects. Plasma levels of 9 biomarkers were measured at diagnosis (baseline, day 0, and D0) and after 30 days (day 30-D30). Patient demographics, clinical data, and biomarker concentrations were analyzed. Serum concentrations of D-dimer, von Willebrand factor, C-reactive protein, and Anti-Xa were elevated in DVT groups at D0 compared to controls. No significant differences were observed between the provoked and unprovoked groups on the day of diagnosis and 30 days later. Over 30 days, the provoked group exhibited significant biomarker changes related to temporal assessment. No significant differences were noted in the biomarker profile between provoked and unprovoked DVT groups. This study is indicative of the concept of individualized thrombosis assessment and subsequent treatment for VTE. Larger cohorts are warranted to validate these findings and further define the most appropriate use of the molecular markers.

Management of lower-extremity venous thromboembolism: An updated review.

According to the 2021 updated guidelines of the American College of Chest Physicians, the location of venous thromboembolism, the severity of symptoms, the risk of thrombus extension vs that of bleeding, and comorbidities all affect the decision to treat, the choice of anti-thrombotic agent, and the duration of therapy. In patients with isolated distal deep vein thrombosis without high-risk features, monitoring progression is recommended over initiating anticoagulation. However, treatment of proximal deep vein thrombosis with anticoagulation is strongly recommended by the guidelines. More evidence now supports the treatment of superficial vein thrombosis with anticoagulation in high-risk patients.

Genetic associations of protein-coding variants in venous thromboembolism.

Previous genetic studies of venous thromboembolism (VTE) have been largely limited to common variants, leaving the genetic determinants relatively incomplete. We performed an exome-wide association study of VTE among 14,723 cases and 334,315 controls. Fourteen known and four novel genes (SRSF6, PHPT1, CGN, and MAP3K2) were identified through protein-coding variants, with broad replication in the FinnGen cohort. Most genes we discovered exhibited the potential to predict future VTE events in longitudinal analysis. Notably, we provide evidence for the additive contribution of rare coding variants to known genome-wide polygenic risk in shaping VTE risk. The identified genes were enriched in pathways affecting coagulation and platelet activation, along with liver-specific expression. The pleiotropic effects of these genes indicated the potential involvement of coagulation factors, blood cell traits, liver function, and immunometabolic processes in VTE pathogenesis. In conclusion, our study unveils the valuable contribution of protein-coding variants in VTE etiology and sheds new light on its risk stratification.

International Normalized Ratio Predicts Recurrence and Bleeding in Patients With Acute Venous Thromboembolism Who Undergo Direct Oral Anticoagulants.

Prothrombin time/international normalized ratio (PT/INR) is related to both antithrombotic effect and risk of bleeding. Its role in the prediction of venous thromboembolism (VTE) recurrence and bleeding for patients with acute VTE who undergo direct oral anticoagulants (DOACs) treatment is unclear, despite previous studies revealed some association between them. The predictive efficiency of INR for VTE recurrence and bleeding were analyzed in a retrospective cohort with VTE patients who underwent DOACs treatment. Then its predictive efficiency for VTE recurrence and bleeding were validated in a prospective cohort with the acquired cutoffs range, and compared with anti-Xa level, DASH and VTE-BLEED scores. In the retrospective cohort (n = 1083), the sensitivity and specificity of INR for the prediction of VTE recurrence were 79.4% and 92.8%, respectively. The area under the curve (AUC) was 0.881 (0.803-0.960)(P = .025). The cutoff value of INR was 0.9. The sensitivity and specificity of INR for the prediction of bleeding were 85.7% and 77.9%, respectively. The AUC was 0.876 (0.786-0.967)(P < .001). The cutoff value of INR was 2.1. In the prospective cohort (n = 202), the calibration showed that there were 4 (50%) patients with VTE recurrence, 156 (97.5%) patients with non-recurrence and bleeding (non-R&B), and 20 (58.8%) patients with bleeding in the low (INR < 0.9)(n = 8), intermediate (0.9 ≤ INR ≤ 2.1)(n = 160), and high (INR > 2.1)(n = 34) groups, respectively. The baseline PT/INR value at the initiation of DOACs treatment is an independent predictor for VTE recurrence and bleeding in patients with acute VTE who undergo DOACs treatment.

Trombosis venosa cerebral / Cerebral venous thrombosis

La trombosis venosa cerebral forma parte de las llamadas trombosis en sitios inusuales. Se define como una oclusión en el territorio venoso cerebral. Su incidencia se encuentra en aumento progresivo, especialmente en países en vías de desarrollo. Se observa con más frecuencia en mujeres jóvenes, siendo los factores hormonales, como el embarazo o la anticoncepción hormonal, factores de riesgo principales en el desarrollo de esta afección. La clínica va a depender fundamentalmente de la topografía de la trombosis, con un diagnóstico de confirmación basado principalmente en las pruebas de imagen. El tratamiento consiste generalmente en la anticoagulación, pudiendo plantearse otras opciones según la gravedad del cuadro. En general, el pronóstico es mejor que el de otros trastornos vasculares intracraneales. En esta revisión se describe la evidencia actual disponible acerca de la trombosis venosa cerebral.(AU)

Cerebral venous thrombosis is part of the so-called thrombosis in unusual sites. It is defined as an occlusion in the cerebral venous territory. Its incidence is progressively increasing, especially in developing countries. It is more frequently observed in young women, with hormonal factors such as pregnancy or hormonal contraception being significant risk factors in the development of this condition. The clinical presentation will depend fundamentally on the topography of the thrombosis, with a confirmatory diagnosis based mainly on imaging tests. The treatment generally consists of anticoagulation, and other options may be considered depending on the severity of the case. Overall, the prognosis is better than that of other intracranial vascular disorders. This review describes the current evidence available regarding cerebral venous thrombosis.(AU)

Multiple adverse outcomes associated with antipsychotic use in people with dementia: population based matched cohort study.

OBJECTIVE: To investigate risks of multiple adverse outcomes associated with use of antipsychotics in people with dementia. DESIGN: Population based matched cohort study. SETTING: Linked primary care, hospital and mortality data from Clinical Practice Research Datalink (CPRD), England. POPULATION: Adults (≥50 years) with a diagnosis of dementia between 1 January 1998 and 31 May 2018 (n=173 910, 63.0% women). Each new antipsychotic user (n=35 339, 62.5% women) was matched with up to 15 non-users using incidence density sampling. MAIN OUTCOME MEASURES: The main outcomes were stroke, venous thromboembolism, myocardial infarction, heart failure, ventricular arrhythmia, fracture, pneumonia, and acute kidney injury, stratified by periods of antipsychotic use, with absolute risks calculated using cumulative incidence in antipsychotic users versus matched comparators. An unrelated (negative control) outcome of appendicitis and cholecystitis combined was also investigated to detect potential unmeasured confounding. RESULTS: Compared with non-use, any antipsychotic use was associated with increased risks of all outcomes, except ventricular arrhythmia. Current use (90 days after a prescription) was associated with elevated risks of pneumonia (hazard ratio 2.19, 95% confidence interval (CI) 2.10 to 2.28), acute kidney injury (1.72, 1.61 to 1.84), venous thromboembolism (1.62, 1.46 to 1.80), stroke (1.61, 1.52 to 1.71), fracture (1.43, 1.35 to 1.52), myocardial infarction (1.28, 1.15 to 1.42), and heart failure (1.27, 1.18 to 1.37). No increased risks were observed for the negative control outcome (appendicitis and cholecystitis). In the 90 days after drug initiation, the cumulative incidence of pneumonia among antipsychotic users was 4.48% (4.26% to 4.71%) versus 1.49% (1.45% to 1.53%) in the matched cohort of non-users (difference 2.99%, 95% CI 2.77% to 3.22%). CONCLUSIONS: Antipsychotic use compared with non-use in adults with dementia was associated with increased risks of stroke, venous thromboembolism, myocardial infarction, heart failure, fracture, pneumonia, and acute kidney injury, but not ventricular arrhythmia. The range of adverse outcomes was wider than previously highlighted in regulatory alerts, with the highest risks soon after initiation of treatment.

External Validation of the Risk Assessment Model of Venous Thromboembolism in Multicenter Internal Medicine Inpatients.

To external validate the risk assessment model (RAM) of venous thromboembolism (VTE) in multicenter internal medicine inpatients. We prospectively collected 595 internal medical patients (310 with VTE patients, 285 non-VTE patients) were from Beijing Shijitan Hospital, Beijing Chaoyang Hospital, and the respiratory department of Beijing Tsinghua Changgeng Hospital from January 2022 to December 2022 for multicenter external validation. The prediction ability of Caprini RAM, Padua RAM, The International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) RAM, and Shijitan (SJT) RAM were compared. This study included a total of 595 internal medicine inpatients, including 242 (40.67%) in the respiratory department, 17 (2.86%) in the respiratory intensive care unit, 49 (8.24%) in the neurology department, 34 (5.71%) in the intensive care unit, 26 (4.37%) in the geriatric department, 22 (3.70%) in the emergency department, 71 (11.93%) in the nephrology department, 63 (10.59%) in the cardiology department, 24 (4.03%) in the hematology department, 6 (1.01%) in the traditional Chinese medicine department, 9 (1.51%) cases in the rheumatology department, 7 (1.18%) in the endocrinology department, 14 (2.35%) in the oncology department, and 11 (1.85%) in the gastroenterology department. Multivariate logistic regression analysis showed that among internal medicine inpatients, age > 60 years old, heart failure, nephrotic syndrome, tumors, history of VTE, and elevated D-dimer were significantly correlated with the occurrence of VTE (P < .05). The incidence of VTE increases with the increase of D-dimer. It was found that the effectiveness of SJT RAM (AUC = 0.80 ± 0.03) was better than Caprini RAM (AUC = 0.74 ± 0.03), Padua RAM (AUC = 0.72 ± 0.03) and IMPROVE RAM (AUC = 0.52 ± 0.03) (P < .05). The sensitivity and Yoden index of SJT RAM were higher than those of Caprini RAM, Pauda RAM, and IMPROVE RAM (P < .05), but specificity was not significantly different between the 4 models (P > .05). The SJT RAM derived from general hospitalized Chinese patients has effective and better predictive ability for internal medicine inpatients at risk of VTE.

Identification and management of pediatric venous thromboembolism in the emergency department.

Although the incidence of pediatric venous thromboembolism is increasing, it is often overlooked in children due to the overall low incidence. This issue reviews the epidemiology of pediatric venous thromboembolism, including the factors that have led to its increasing prevalence, and discusses the physiology of hemostasis and coagulation. Key features of the history and physical examination, as well as identification of risk factors, are reviewed, as these have the most diagnostic value for venous thromboembolism in pediatric patients. Recommendations are also provided for diagnostic testing and management in the emergency department.

Aspirin or enoxaparin for VTE prophylaxis after primary partial, total or revision hip or knee arthroplasty: A secondary analysis from the CRISTAL cluster randomized trial.

BACKGROUND: This study compares aspirin to enoxaparin for symptomatic VTE prophylaxis within 90 days of any type of hip or knee arthroplasty performed for any diagnosis, in patients enrolled in the CRISTAL trial. MATERIALS AND METHODS: CRISTAL was a cluster-randomised crossover, registry-nested non-inferiority trial across 31 hospitals in Australia. The primary publication was restricted to patients undergoing primary total hip or knee arthroplasty for a diagnosis of osteoarthritis. This report includes all enrolled patients undergoing hip or knee arthroplasty procedures (partial or total, primary or revision) performed for any indication. Hospitals were randomized to administer patients aspirin (100mg daily) or enoxaparin (40mg daily), for 35 days after hip arthroplasty and 14 days after knee arthroplasty. Crossover occurred after the patient enrolment target had been met for the first group. The primary outcome was symptomatic VTE within 90 days. Analyses were performed by randomization group. RESULTS: Between April 20, 2019 and December 18, 2020, 12384 patients were enrolled (7238 aspirin group and 5146 enoxaparin). Of these, 6901 (95.3%) given aspirin and 4827 (93.8%) given enoxaparin (total 11728, 94.7%) were included in the final analyses. Within 90 days, symptomatic VTE occurred in 226 (3.27%) aspirin patients and 85 (1.76%) enoxaparin patients, significant for the superiority of enoxaparin (estimated treatment difference 1.85%, 95% CI 0.59% to 3.10%, p = 0.004). Joint-related reoperation within 90 days was lower in the enoxaparin group (109/4827 (2.26%) vs 171/6896 (2.47%) with aspirin, estimated difference 0.77%; 95% CI 0.06% to 1.47%, p = 0.03). There were no significant differences in the other secondary outcomes. CONCLUSION: In patients undergoing hip or knee arthroplasty (of any type, performed for any indication) enrolled in the CRISTAL trial, aspirin compared to enoxaparin resulted in a significantly higher rate of symptomatic VTE and joint-related reoperation within 90 days. These findings extend the applicability of the CRISTAL trial results. TRIAL REGISTRATION: Anzctr.org.au, identifier: ACTRN12618001879257.

Risk of extended major adverse cardiovascular event endpoints with tofacitinib versus TNF inhibitors in patients with rheumatoid arthritis: a post hoc analysis of a phase 3b/4 randomised safety study.

OBJECTIVES: Compare the risk of extended major adverse cardiovascular (CV) event (MACE) composite outcomes and component events in patients with rheumatoid arthritis (RA) treated with tofacitinib versus tumour necrosis factor inhibitors (TNFi) in Oral Rheumatoid Arthritis Trial (ORAL) Surveillance. METHODS: Patients with RA aged ≥50 years and with ≥1 additional CV risk factor received tofacitinib 5 mg or 10 mg two times per day or TNFi. MACE (non-fatal myocardial infarction (MI), non-fatal stroke or CV death (MACE-3)) was extended by sequential addition of CV events (hospitalisation for unstable angina (MACE-4), coronary revascularisation (MACE-5), transient ischaemic attack (MACE-6), peripheral vascular disease (MACE-7)), heart failure (HF) hospitalisation (MACE-8) and venous thromboembolism (VTE; (MACE-8 plus VTE)). HRs (tofacitinib vs TNFi) were evaluated for MACE and individual components. RESULTS: HRs for MACE-4 to MACE-8 with combined and individual tofacitinib doses versus TNFi were similar. Risk of MACE-8 plus VTE appeared similar with tofacitinib 5 mg two times per day versus TNFi (HR 1.12 (0.82 to 1.52)), but higher with tofacitinib 10 mg two times per day versus TNFi (HR 1.38 (1.02 to 1.85)). Risk of MI was higher with tofacitinib versus TNFi, but difference in risk of other individual CV events was not suggested. Across extended MACE definitions, risk appeared higher with tofacitinib versus TNFi in those with atherosclerotic CV disease or age ≥65 years. CONCLUSION: In ORAL Surveillance, risk of composite CV endpoints combining all ischaemic CV events and HF did not appear different with tofacitinib versus TNFi. The totality of CV risk was higher with tofacitinib 10 mg two times per day versus TNFi, driven by an increase in VTE. TRIAL REGISTRATION NUMBER: NCT02092467.

Predictive factors of clot propagation in patients with superficial venous thrombosis towards deep venous thrombosis and pulmonary embolism: a systematic review and meta-analysis.

OBJECTIVE: A subset of patients with superficial venous thrombosis (SVT) experiences clot propagation towards deep venous thrombosis (DVT) and/or pulmonary embolism (PE). The aim of this systematic review is to identify all clinically relevant cross-sectional and prognostic factors for predicting thrombotic complications in patients with SVT. DESIGN: Systematic review. DATA SOURCES: PubMed/MEDLINE and Embase were systematically searched until 3 March 2023. ELIGIBILITY CRITERIA: Original research studies with patients with SVT, DVT and/or PE as the outcome and presenting cross-sectional or prognostic predictive factors. DATA EXTRACTION AND SYNTHESIS OF RESULTS: The CHecklist for critical Appraisal and data extraction for systematic Reviews of prediction Modelling (CHARMS) checklist for prognostic factor studies was used for systematic extraction of study characteristics. Per identified predictive factor, relevant estimates of univariable and multivariable predictor-outcome associations were extracted, such as ORs and HRs. Estimates of association for the most frequently reported predictors were summarised in forest plots, and meta-analyses with heterogeneity were presented. The Quality in Prognosis Studies (QUIPS) tool was used for risk of bias assessment and Grading of Recommendations, Assessment, Development and Evaluations (GRADE) for assessing the certainty of evidence. RESULTS: Twenty-two studies were included (n=10 111 patients). The most reported predictive factors were high age, male sex, history of venous thromboembolism (VTE), absence of varicose veins and cancer. Pooled effect estimates were heterogenous and ranged from OR 3.12 (95% CI 1.75 to 5.59) for the cross-sectional predictor cancer to OR 0.92 (95% CI 0.56 to 1.53) for the prognostic predictor high age. The level of evidence was rated very low to low. Most studies were scored high or moderate risk of bias. CONCLUSIONS: Although the pooled estimates of the predictors high age, male sex, history of VTE, cancer and absence of varicose veins showed predictive potential in isolation, variability in study designs, lack of multivariable adjustment and high risk of bias prevent firm conclusions. High-quality, multivariable studies are necessary to be able to identify individual SVT risk profiles. PROSPERO REGISTRATION NUMBER: CRD42021262819.

Evaluation of venous thromboembolism risk assessment models for hospital inpatients: the VTEAM evidence synthesis.

Background: Pharmacological prophylaxis during hospital admission can reduce the risk of acquired blood clots (venous thromboembolism) but may cause complications, such as bleeding. Using a risk assessment model to predict the risk of blood clots could facilitate selection of patients for prophylaxis and optimise the balance of benefits, risks and costs. Objectives: We aimed to identify validated risk assessment models and estimate their prognostic accuracy, evaluate the cost-effectiveness of different strategies for selecting hospitalised patients for prophylaxis, assess the feasibility of using efficient research methods and estimate key parameters for future research. Design: We undertook a systematic review, decision-analytic modelling and observational cohort study conducted in accordance with Enhancing the QUAlity and Transparency Of health Research (EQUATOR) guidelines. Setting: NHS hospitals, with primary data collection at four sites. Participants: Medical and surgical hospital inpatients, excluding paediatric, critical care and pregnancy-related admissions. Interventions: Prophylaxis for all patients, none and according to selected risk assessment models. Main outcome measures: Model accuracy for predicting blood clots, lifetime costs and quality-adjusted life-years associated with alternative strategies, accuracy of efficient methods for identifying key outcomes and proportion of inpatients recommended prophylaxis using different models. Results: We identified 24 validated risk assessment models, but low-quality heterogeneous data suggested weak accuracy for prediction of blood clots and generally high risk of bias in all studies. Decision-analytic modelling showed that pharmacological prophylaxis for all eligible is generally more cost-effective than model-based strategies for both medical and surgical inpatients, when valuing a quality-adjusted life-year at £20,000. The findings were more sensitive to uncertainties in the surgical population; strategies using risk assessment models were more cost-effective if the model was assumed to have a very high sensitivity, or the long-term risks of post-thrombotic complications were lower. Efficient methods using routine data did not accurately identify blood clots or bleeding events and several pre-specified feasibility criteria were not met. Theoretical prophylaxis rates across an inpatient cohort based on existing risk assessment models ranged from 13% to 91%. Limitations: Existing studies may underestimate the accuracy of risk assessment models, leading to underestimation of their cost-effectiveness. The cost-effectiveness findings do not apply to patients with an increased risk of bleeding. Mechanical thromboprophylaxis options were excluded from the modelling. Primary data collection was predominately retrospective, risking case ascertainment bias. Conclusions: Thromboprophylaxis for all patients appears to be generally more cost-effective than using a risk assessment model, in hospitalised patients at low risk of bleeding. To be cost-effective, any risk assessment model would need to be highly sensitive. Current evidence on risk assessment models is at high risk of bias and our findings should be interpreted in this context. We were unable to demonstrate the feasibility of using efficient methods to accurately detect relevant outcomes for future research. Future work: Further research should evaluate routine prophylaxis strategies for all eligible hospitalised patients. Models that could accurately identify individuals at very low risk of blood clots (who could discontinue prophylaxis) warrant further evaluation. Study registration: This study is registered as PROSPERO CRD42020165778 and Researchregistry5216. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR127454) and will be published in full in Health Technology Assessment; Vol. 28, No. 20. See the NIHR Funding and Awards website for further award information.

People who are admitted to hospital are at risk of blood clots that can cause serious illness or death. Patients are often given low doses of blood-thinning drugs to reduce this risk. However, these drugs can cause side effects, such as bleeding. Hospitals currently use complex risk assessment models (risk scores, which usually include patient, disease, mobility and intervention factors) to determine the individual risk of blood clots and identify people most likely to benefit from blood-thinning drugs. There are a lot of different risk scores and we do not know which one is best. We also do not know how these scores compare to each other or whether using scores to decide who should get blood-thinning drugs provides good value for money to the NHS. We reviewed all previous studies of risk scores. We found that they did not predict blood clots very well and we could not recommend one score over another. We then created a mathematical model to simulate the use of blood-thinning drugs in people admitted to hospital. The model suggested that giving blood-thinning drugs to everyone who could have them would probably provide the best value for money, in medical patients. Our findings were the same, but less certain, for surgical patients. We also collected information from four NHS hospitals to explore possibilities for future research. Our work showed that routinely collected electronic data on blood clots and bleeding events is not very accurate and that using different scores could result in variable use of blood-thinning medications. Our findings suggest that it may be better value to the NHS and better for patients if we were to offer blood-thinning medications to everyone on admission to hospital, without using any risk score. However, this approach needs further research to ensure it is safe and effective. Such research would not be able to rely on routine electronic data to identify blood clots or bleeding events, in isolation.

Evaluating of Existing VTE Risk Scales in Glioma Patients.

INTRODUCTION: Postoperative venous thromboembolism (VTE) is a frequently occurring complication among glioma patients. Several risk assessment models (RAMs), including the Caprini RAM, the IMPROVE Risk Score, the IMPROVED VTE Risk Score, and the Padua Prediction Score, have not been validated within the glioma patient population. The purpose of this study was to assess the predictive accuracy of established VTE risk scales in patients with glioma. MATERIALS AND METHODS: A single-center, retrospective, observational cohort study was conducted on 265 glioma patients who underwent surgery at the Almazov Medical and Research Centre between 2021 and 2022. VTE detection followed the current clinical guidelines. Threshold values for the Caprini, IMPROVE VTE, IMPROVEDD, and Padua scales were determined using ROC analysis methods, with cumulative weighting for sensitivity and specificity in predicting VTE development. The areas under the ROC curves (AUC) were calculated, and comparisons were made using the DeLong test. RESULTS: The area under the curve for the Caprini risk assessment model was 80.41, while the IMPROVEDD VTE risk score was 75.38, the Padua prediction score was 76.9, and the IMPROVE risk score was 72.58. No significant differences were observed in the AUC values for any of the scales. The positive predictive values of all four scales were low, with values of 50 (28-72) for Caprini, 48 (28-69) for IMPROVEDD VTE, 50 (30-70) for Padua, and 64 (35-87) for IMPROVE RAM. No significant differences were found in terms of PPV, NPV, positive likelihood ratio, and negative likelihood ratio among the analyzed scales. CONCLUSIONS: The Caprini Risk Assessment Model, the IMPROVE Risk Score, the IMPROVED VTE Risk Score, and the Padua Prediction Score exhibit acceptable specificity and sensitivity for glioma patients. However, their low positive predictive ability, coupled with the complexity of interpretation, limits their utility in neurosurgical practice.