Derivation and Validation of a Clinical Prediction Scale for Isolated Distal Deep Venous Thrombosis in Patients after Acute Ischemic Stroke

Joint effect of ischemic stroke and obesity on the risk of venous thromboembolism: the Tromsø Study

Background

Patients with ischemic stroke have increased risk of venous thromboembolism (VTE). Obesity is prevalent in stroke patients and a well-established risk factor for VTE. Whether obesity further increases the VTE risk in patients with stroke remains unclear.

Objectives

We investigated the joint effect of ischemic stroke and obesity on the risk of incident VTE in a population-based cohort.

Methods

Participants (n = 29,920) were recruited from the fourth to sixth surveys of the Tromsø Study (1994-1995, 2001, and 2007-2008) and followed through 2014. Incident events of ischemic stroke and VTE during follow-up were recorded. Hazard ratios (HRs) of VTE with 95% CIs were estimated according to combined categories of ischemic stroke and obesity (body mass index ≥ 30 kg/m2), with exposure to neither risk factors as reference.

Results

During a median follow-up of 19.6 years, 1388 participants experienced ischemic stroke and 807 participants developed VTE. Among those with stroke, 51 developed VTE, yielding an incidence rate of VTE after stroke of 7.2 per 1000 person-years (95% CI, 5.5-9.5). In subjects without stroke, obesity was associated with a 1.8-fold higher VTE risk (HR, 1.76; 95% CI, 1.47-2.11). In nonobese subjects, stroke was associated with a 1.8-fold higher VTE risk (HR, 1.77; 95% CI, 1.27-2.46). Obese subjects with stroke had a 2-fold increased VTE risk (HR, 2.44; 95% CI, 1.37-4.36).

Conclusion

The combination of obesity and ischemic stroke did not yield an excess risk of VTE. Our findings suggest that obese subjects with ischemic stroke do not have a more than additive risk of VTE.

Nomogram for Risk of Secondary Venous Thromboembolism in Stroke Patients: A Study Based on the MIMIC-IV Database

This study aims to identify risk factors for secondary venous thromboembolism (VTE) in stroke patients and establish a nomogram, an accurate predictor of probability of VTE occurrence during hospitalization in stroke patients. Medical Information Mart for Intensive Care IV (MIMIC-IV) database of critical care medicine was utilized to retrieve information of stroke patients admitted to the hospital between 2008 and 2019. Patients were randomly allocated into train set and test set at 7:3. Univariate and multivariate logistic regression analyses were used to identify independent risk factors for secondary VTE in stroke patients. A predictive nomogram model was constructed, and the predictive ability of the nomogram was evaluated using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). This study included 266 stroke patients, with 26 patients suffering secondary VTE after stroke. A nomogram for predicting risk of secondary VTE in stroke patients was built according to pulmonary infection, partial thromboplastin time (PTT), log-formed D-dimer, and mean corpuscular hemoglobin (MCH). Area under the curve (AUC) of the predictive model nomogram was 0.880 and 0.878 in the train and test sets, respectively. The calibration curve was near the diagonal, and DCA curve presented positive net benefit. This indicates the model's good predictive performance and clinical utility. The nomogram effectively predicts the risk probability of secondary VTE in stroke patients, aiding clinicians in early identification and personalized treatment of stroke patients at risk of developing secondary VTE.

Risk factors for lower extremity deep vein thrombosis in acute stroke patients following endovascular thrombectomy: a retrospective cohort study

Background

Deep vein thrombosis (DVT) in lower extremities as a common complication of acute ischemic stroke (AIS) has long been studied. However, as the therapeutic options for AIS continue to advance, the pathogenic mechanisms behind DVT may change. Endovascular thrombectomy (EVT) has replaced intravenous thrombolysis and become the preferred treatment for AIS patients with large vessel occlusions. Therefore, it is important to update our understanding of DVT and its management. This study aimed to determine the prevalence and risk factors of DVT in AIS patients following EVT.

Methods

In this retrospective study, 245 AIS patients who had received EVT were recruited between January 2020 and December 2021. Within 10 days (median 4 days) of thrombectomy, DVT was diagnosed by ultrasonography. Demographic characteristics, clinical findings, and therapeutic procedures were compared between patients with and without DVT using univariate analysis. Cutoff points were defined for EVT time and plasma D-dimer concentration. Multivariable logistic regression was then used to determine the independent risk factors for DVT and evaluate their predictive power.

Results

The prevalence of DVT in AIS patients after EVT was 27.3%. Multifactorial logistic regression analysis showed that age (OR 1.036, 95% CI 1.001-1.073; P = 0.045), female sex (OR 3.015, 95% CI 1.446-6.289; P = 0.003), lower limb muscle strength less than grade three (OR 7.015, 95% CI 1.887-26.080; P = 0.004), longer EVT time (OR 1.012, 95% CI 1.004-1.020; P = 0.003), and higher D-dimer levels (OR 1.350, 95% CI 1.150-1.585; P < 0.001) were independently associated with higher DVT risk in AIS patients following EVT. The cutoff points for operative time of EVT and plasma D-dimer were 65.5 min and 1.62 mg/L, respectively, above which the risk for DVT was dramatically increased with OR > 4 in AIS patients.

Conclusion

AIS patients are at increased risk of developing DVT following EVT particularly if they have undergone prolonged thrombectomy procedures and exhibit high plasma levels of D-dimers. However, the results of our study need to be validated by a multicenter prospective study with a larger population of stroke patients.

Risk factors and predictors for venous thromboembolism in people with ischemic stroke: A systematic review

Identification of individuals with ischemic stroke at particularly high risk of venous thromboembolism (VTE) is crucial for targeted thromboprophylaxis. To guide clinical decision-making and development of risk prediction models, increased knowledge on risk factors and biomarkers is needed. Therefore, we set out to identify risk factors and predictors for VTE in people with ischemic stroke by conducting a systematic review of the literature. Medline and Embase were searched from January 1990 and onwards. Studies investigating demographic, clinical, and/or laboratory factors for stroke-related VTE were considered. Two reviewers screened all retrieved records, independently and in duplicate. Risk of bias assessments were guided by a structured framework (PROSPERO-ID: CRD42020176361). Of 4674 identified records, 26 studies were included. Twenty-six demographic, clinical, and laboratory factors associated with increased risk of stroke-related VTE after multivariable adjustments were identified. The following factors were reported by ≥2 studies: prior VTE, cancer, prestroke disability, leg weakness, increasing lesion volume of the brain infarct, infection, low Barthel Index, increasing length of hospital stay, biochemical indices of dehydration, as well as elevated levels of D-dimer, C-reactive protein, and homocysteine. The majority of the studies were of poor quality with moderate or high risk of bias. In conclusion, this systematic review informs on several potential risk factors and predictors for VTE in people with ischemic stroke. To improve risk stratification and guide development of risk prediction models, further confirmation is needed because there were few high-quality studies on each factor.

Development and Validation of Prediction Models for Severe Complications After Acute Ischemic Stroke: A Study Based on the Stroke Registry of Northwestern Germany

Background

The treatment of stroke has been undergoing rapid changes. As treatment options progress, prediction of those under risk for complications becomes more important. Available models have, however, frequently been built based on data no longer representative of today’s care, in particular with respect to acute stroke management. Our aim was to build and validate prediction models for 4 clinically important, severe outcomes after stroke.

Methods and Results

We used German registry data from 152 710 patients with acute ischemic stroke obtained in 2016 (development) and 2017 (validation). We took into account potential predictors that were available at admission and focused on in‐hospital mortality, intracranial mass effect, secondary intracerebral hemorrhage, and deep vein thrombosis as outcomes. Validation cohort prediction and calibration performances were assessed using the following 4 statistical approaches: logistic regression with backward selection, l1‐regularized logistic regression, k‐nearest neighbor, and gradient boosting classifier. In‐hospital mortality and intracranial mass effects could be predicted with high accuracy (both areas under the curve, 0.90 [95% CI, 0.90–0.90]), whereas the areas under the curve for intracerebral hemorrhage (0.80 [95% CI, 0.80–0.80]) and deep vein thrombosis (0.73 [95% CI, 0.73–0.73]) were considerably lower. Stroke severity was the overall most important predictor. Models based on gradient boosting achieved better performances than those based on logistic regression for all outcomes. However, area under the curve estimates differed by a maximum of 0.02.

Conclusions

We validated prediction models for 4 severe outcomes after acute ischemic stroke based on routinely collected, recent clinical data. Model performance was superior to previously proposed approaches. These predictions may help to identify patients at risk early after stroke and thus facilitate an individualized level of care.

Relationship between cerebral venous sinus thrombosis and intracranial arteritis during pregnancy and post partum

Our study was conducted to explore the relationship between cerebral venous sinus thrombosis (CVST) and intracranial arteritis during the time of pregnancy as well as puerperium. The current retrospective case study involved a total of 153 patients with pregnancy-related CVST. CVST was diagnosed mainly based on clinical manifestations and imaging results. Detailed information on demographics, risk factors (excluding intracranial arteritis), and pregnancy outcomes was systematically recorded. The average age of patients diagnosed with CVST was 28.67±3.54 years old. Among these patients, there were 62 cases of puerperal CVST and 91 cases of pregnancy-related CVST. The clinical manifestations of patients with CVST included headache in 55 cases (35.95%), symptomatic seizures in 26 cases (16.99%), symptomatic limb weakness in 22 cases (14.38%), symptomatic nausea/vomiting in 18 cases (11.76%), symptomatic disturbance of consciousness in 15 cases (9.80%), symptomatic blurred vision in 10 cases (6.54%), and symptomatic fever in 7 cases (4.58%). A proportion of patients reported higher abnormal cerebrospinal fluid pressure (98.28%), white cell count (79.31%), total cholesterol (71.55%) and low-density lipoprotein (62.93%) (p<0.01). The proportion of intracranial arteritis lesions and CVST lesions was high, including 51 cases (43.97%) on the left side and 31 cases (26.72%) on the right side. Bilateral CVST lesions occurred in 13 cases (11.20%) of unilateral intracranial arteritis lesions, and bilateral intracranial arteritis lesions occurred in 16 cases (13.79%) of unilateral CVST lesions. In summary, CVST indicates a potential positive link to intracranial arteritis at the time of pregnancy and puerperium.

A nomogram based on easily obtainable parameters for distal deep venous thrombosis in patients after acute stroke

OBJECTIVES

To develop and validate a nomogram to predict the probability of distal deep venous thrombosis (DVT) within first 14 days of stroke onset in patients by using easily obtainable parameters.

METHODS

This is a retrospective study. The presence of distal DVT was evaluated using ultrasonography within the first 14 days. Data were randomly assigned to either a modelling data set or a validation data set. Univariable and multivariate logistic regression analysis was used to determine risk scores to predict distal DVT in the modelling data set, and nomogram and calibration curve were constructed by R project.

RESULTS

A total of 1620 patients with acute stroke were enrolled in the study. The multivariate analysis revealed that the old age, female gender, haemorrhagic stroke, coronary heart disease, lower limb weakness, a low serum albumin level, and a high D-dimer level are highly predictive of 14-day risk of distal DVT. The AUC of the nomogram to predict the 14-day risk of distal DVT was 0.785 (95% CI, 0.742-0.827) and 0.813 (0.766-0.860) for the modelling cohort and external validation cohort, respectively. Moreover, the calibration of the nomogram showed a nonsignificant Hosmer-Lemeshow test statistic in the modelling (P = 0.876) and validation (P = 0.802) sets. With respect to decision curve analyses, the nomogram exhibited preferable net benefit gains than the staging system across a wide range of threshold probabilities.

CONCLUSION

The established nomogram displayed a superior performance in terms of predictive accuracy, discrimination capability, and clinical utility, may be helpful for clinicians to identify high-risk groups of distal DVT.

Development and Validation of a Nomogram for Lower Extremity Deep Venous Thrombosis in Patients after Acute Stroke

OBJECTIVES

To develope and validate a nomogram to predict the probability of deep venous thrombosis (DVT) in patients after acute stroke during the first 14 days with clinical features and easily obtainable biochemical parameters.

METHODS

This is a single-center prospective cohort study. The potential predictive variables for DVT at baseline were collected, and the presence of DVT was evaluated using ultrasonography within the first 14 days. Data were randomly assigned to either a modeling data set or a validation data set. Univariable and Multivariate logistic regression analysis was used to develop risk scores to predict DVT in the modeling data set and the area under the receiver operating characteristic curve to validate the score in the test data set, and nomogram and calibration curve were constructed by R project.

RESULTS

A total of 1651 patients with acute stroke were enrolled in the study. The overall incidence of DVT after acute stroke within two weeks was 14.4%. Multivariable analysis detected older age (≥65 years),female gender, hemorrhagic stroke, malignancy, lower limb muscle strength<3 grade, Albumin<40 g·L^-1 and D-dimer>0.5 mg·L^-1 were highly predictive of 14-day risk of DVT. The AUC of the nomogram with these above-mentioned independent risk factors to predict the 14-day risk of DVT was 0.756 (95% CI, 0.712-0.812) and 0.811 (95%CI, 0.762-0.859) for the modeling cohort and external validation cohort, respectively. Moreover, the calibration of the nomogram showed a nonsignificant Hosmer-Lemeshow test statistic in the modeling (P = 0.250) and validation sets (P = 0.995). With respect to decision curve analyses, the nomogram exhibited preferable net benefit gains than the staging system across a wide range of threshold probabilities.

CONCLUSION

This nomogram had a good performance in predictive accuracy, discrimination capability, and clinical utility, which was helpful for clinicians to identify high-risk groups of DVT and formulate relevant prevention and treatment measures.

Literature review of distal deep vein thrombosis

OBJECTIVE

Although distal deep vein thrombosis (DDVT) has been more frequently diagnosed with the availability of better ultrasound imaging quality, the data on the best method to manage DDVT have been conflicting. The aim of the present review was to summarize the current and evidence-based recommendations for the diagnosis and management of DDVT and to provide a summary of the most recent societal guideline recommendations.

METHODS

A literature review of DDVT was performed. The PubMed databases were queried for articles on the epidemiology, risk factors, diagnosis, and management of DDVT.

RESULTS

The prevalence of isolated DDVT has been reported in a broad range. The reported risk factors include older age, active malignancy, a low degree of mobility, acute infection, and atrial fibrillation. With more evidence, anticoagulation therapy was found to be associated with a reduced risk of recurrent venous thromboembolism (VTE) and/or thrombus propagation compared with conservative management. However, anticoagulation was associated with an increased risk of bleeding in a number of studies. The rate of VTE recurrence ranged from 7% to 23% during a follow-up period ranging from 3 months to 8 years. The significant risk factors for VTE recurrence included cancer, older age, an unprovoked event, and inpatient status.

CONCLUSIONS

Few studies have addressed the diagnosis and management of DDVT. Further research is needed to standardize the best approach to diagnose and treat DDVT.

The Role of Stroke as a Trigger for Incident Venous Thromboembolism: Results from a Population-based Case-Crossover Study

Stroke is associated with a short-term increased risk of subsequent venous thromboembolism (VTE). It is unclear to what extent this association is mediated by stroke-related complications that are potential triggers for VTE, such as immobilization and infection. We aimed to investigate the role of acute stroke as a trigger for incident VTE while taking other concomitant VTE triggers into account. We conducted a population-based case-crossover study with 707 VTE patients. Triggers were registered during the 90 days before a VTE event (hazard period) and in four preceding 90-day control periods. Conditional logistic regression was used to estimate odds ratios with 95% confidence intervals (CIs) for VTE according to triggers. Stroke was registered in 30 of the 707 (4.2%) hazard periods and in 6 of the 2,828 (0.2%) control periods, resulting in a high risk of VTE, with odds ratios of 20.0 (95% CI: 8.3–48.1). After adjustments for immobilization and infection, odds ratios for VTE conferred by stroke were attenuated to 6.0 (95% CI: 1.6–22.1), and further to 4.0 (95% CI: 1.1–14.2) when other triggers (major surgery, red blood cell transfusion, trauma, and central venous catheter) were added to the regression model. A mediation analysis revealed that 67.8% of the total effect of stroke on VTE risk could be mediated through immobilization and infection. Analyses restricted to ischemic stroke yielded similar results. In conclusion, acute stroke was a trigger for VTE, and the association between stroke and VTE risk appeared to be largely mediated by immobilization and infection.

Deep Vein Thrombosis in Acute Stroke - A Systemic Review of the Literature

We present a systemic review of available literature on the complications of deep venous thrombosis that develops in patients presenting with acute stroke. There are several pharmacological and physical treatment options available and used. We aim to summarize the management plans currently used at different centers. In conclusion, low-dose anticoagulant therapy for ischemic stroke is recommended. In the case of intracerebral hemorrhage, pneumatic sequential compression devices should be placed initially, followed by the administration of ultra-fractioned heparin on the next day, and then oral anticoagulant therapy to replace the heparin after a week in high-risk patients. Similar prophylactic treatment recommendations are used for subarachnoid hemorrhage.