Research and Practice in Thrombosis and Haemostasis最新文献

Background

Overuse of antiplatelet therapy and underuse of gastroprotection contribute to preventable bleeding in patients taking anticoagulants.

Objectives

(1) Determine the feasibility of a factorial trial testing patient activation and clinician outreach to reduce gastrointestinal (GI) bleeding risk in patients prescribed warfarin–antiplatelet therapy without proton pump inhibitor gastroprotection and (2) assess intervention acceptability.

Methods

Pragmatic 2 × 2 factorial cluster-randomized controlled pilot comparing (1) a patient activation booklet vs usual care and (2) clinician notification vs clinician notification plus nurse facilitation was performed. The primary feasibility outcome was percentage of patients completing a structured telephone assessment after 5 weeks. Exploratory outcomes, including effectiveness, were evaluated using chart review, surveys, and semistructured interviews.

Results

Among 47 eligible patients, 35/47 (74.5%; 95% CI, 58.6%-85.7%) met the feasibility outcome. In the subset confirmed to be high risk for upper GI bleeding, 11/29 (37.9%; 95% CI, 16.9%-64.7%) made a medication change, without differences between intervention arms. In interviews, few patients reported reviewing the activation booklet; barriers included underestimating GI bleeding risk, misunderstanding the booklet’s purpose, and receiving excessive health communication materials. Clinicians responded to notification messages for 24/47 patients (51.1%; 95% CI, 26.4%-75.4%), which was lower for surgeons than nonsurgeons (22.7% vs 76.0%). Medical specialists but not surgeons viewed clinician notification as acceptable.

Conclusion

The proposed trial design and outcome ascertainment strategy were feasible, but the patient activation intervention is unlikely to be effective as designed. While clinician notification appears promising, it may not be acceptable to surgeons, findings which support further refinement and testing of a clinician notification intervention.

Background

To overcome deficiencies of the traditional von Willebrand factor (VWF) ristocetin cofactor activity assay (VWF:RCo), several automated assays for VWF platelet-binding activity have been developed. Information on the performance of these assays and their diagnostic utility remains limited.

Objectives

To validate the VWF:glycoprotein IbM assay INNOVANCE VWF Ac and compare it with an automated VWF:RCo assay as well as with an automated assay and a manual VWF:Ab assay and to generate reference ranges and analyze reproducibility of the VWF:glycoprotein IbM assay.

Methods

Clinical sites enrolled healthy subjects and patients representing the intended use population; VWF activity assays were performed, and results were analyzed. The performance of the INNOVANCE VWF Ac assay was also compared between the BCS XP System and the CS-2500 and CS-5100 analyzers.

Results

The INNOVANCE VWF Ac assay correlated well with the VWF:RCo assay and the automated HemosIL VWF:Ab assay, with Pearson coefficients of >.9 and a predicted bias of ≤5.0 IU/dL at VWF levels of 30 IU/dL and ≤5.8 IU/dL at the levels of 50 IU/dL, but correlation and bias were not as good when compared with the REAADS manual VWF:Ab assay. Reference ranges observed for healthy subjects correlated well with previously published findings. Reproducibility of the INNOVANCE VWF Ac assay on the BCS XP System and the CS analyzers was excellent, as was correlation among devices.

Conclusion

The characteristics of the INNOVANCE VWF Ac assay regarding comparability with other VWF activity assays, reference ranges, and precision support the use of this assay for evaluation of patients with concern for von Willebrand disease.

Background

Biomarkers of fibrinolysis are elevated during acute immunologic reactions (allergic reactions and angioedema), although it is unclear whether fibrinolysis is associated with disease severity.

Objectives

We investigated a possible association between maximum lysis (ML) measured by thromboelastography and the severity of acute immunologic reactions.

Methods

We recruited patients with acute immunologic reactions at a high-volume emergency department. Clinical disease severity at presentation and at the end of the emergency department stay was assessed using a 5-grade scale, ranging from local symptoms to cardiac arrest. We determined ML on admission by thromboelastography (ROTEM's extrinsic [EXTEM], and aprotinin [APTEM] tests), expressed as ML%. Hyperfibrinolysis was defined as an ML of >15% in EXTEM, which was reversed by adding aprotinin (APTEM). We used exact logistic regression to investigate an association between ML% and disease severity (grades 1 and 2 [mild] vs 3-5 [severe]) and between hyperfibrinolysis and disease severity.

Results

We included 31 patients (71% female; median age, 52 [IQR, 35-58] years; 10 [32%] with a severe reaction). ML% was higher in patients with severe symptoms (21 [IQR, 12-100] vs 10 [IQR, 4-17]). Logistic regression found a significant association between ML% and symptom severity (odds ratio, 1.07; 95% CI, 1.01-1.21; P = .003). Hyperfibrinolysis was detected in 6 patients and found to be associated with severe symptoms (odds ratio, 17.59; 95% CI, 1.52-991.09; P = .02). D-dimer, tryptase, and immunoglobulin E concentrations increased with the severity of immunologic reactions.

Conclusion

ML, quantified by thromboelastography, is associated with the severity of acute immunologic reactions.

Background

Multiple guidelines recommend assessment of bleeding and venous thromboembolism (VTE) risk in adult medical inpatients to inform prevention strategies. There is no agreed-upon method for VTE and bleeding risk assessment.

Objectives

To validate the International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) VTE and bleeding risk scores in an independent population.

Methods

In this retrospective study, we calculated the IMPROVE VTE and bleeding risk scores in medical inpatients admitted between 2010 and 2019 at the University of Vermont Medical Center (UVMMC). Patients were followed for in-hospital bleeding events while hospitalized and VTE events while hospitalized and for 3 months after discharge. We assessed calibration of the risk models by comparing the observed incidence of events in the UVMMC and IMPROVE populations across the published risk categories. We also assessed performance of the IMPROVE risk factors after refitting the models in the UVMMC population. Discrimination was assessed using the area under the receiver operating characteristic curve (AUC).

Results

VTE occurred in 270 (1.1%) of 23,873 admissions, with 92 (34%) occurring during admission, and bleeding occurred in 712 (4.7%) of 15,240 admissions. When the IMPROVE-VTE risk factors were refitted to the UVMMC data, the AUC was 0.64. When the IMPROVE bleeding risk factors were refitted to the UVMMC data, the AUC was 0.67. The IMPROVE-VTE score tended to overestimate risk at higher scores, and the IMPROVE bleeding score underestimated risk at lower scores and overestimated risk at higher scores.

Conclusion

While the refitted IMPROVE VTE and bleeding risk scores had reasonable model fit, the scores were poorly calibrated and did not reliably identify or differentiate patients at risk for VTE and bleeding. Different methods are needed for risk assessment of medical inpatients for VTE and bleeding risk.

Direct oral anticoagulants (DOACs) have become the preferred option for treatment of venous thromboembolism due to their favorable profile compared with other agents such as vitamin K antagonists or low-molecular-weight heparin. However, findings from randomized controlled trials suggest efficacy and/or safety concerns with DOAC use in some clinical contexts. This illustrated review will summarize indications where DOACs have proven efficacy and safety, situations where they fall short, and situations where uncertainty remains compared with other treatments for venous thromboembolism.

Background

Cancer-associated venous thromboembolism (CA-VTE) represents a major cause of morbidity and mortality in patients with cancer. Despite poor outcomes, there is an ongoing knowledge gap in epidemiologic data related to this association.

Objectives

To compare venous thromboembolism (VTE) characteristics, risk factors, and outcomes between patients with and without active cancer in a racially diverse population.

Methods

Our surveillance project occurred at the 3 hospitals in Durham County, North Carolina, from April 2012 through March 2014. Electronic and manual methods were used to identify unique Durham County residents with VTE.

Results

We identified 987 patients with VTE during the surveillance period. Of these, 189 patients had active cancer at the time of their VTE event. Patients with CA-VTE were older (median age: 69 years vs 60 years, P < .0001) and had a lower body mass index (median body mass index: 26.0 kg/m² vs 28.4 kg/m², P = .0001) than noncancer patients. The most common cancers in our cohort were gastrointestinal, breast, genitourinary, and lung. The proportion of VTE cases with pulmonary embolism (PE) was greater in the cancer cohort compared with that in the noncancer cohort (58.2% vs 44.0%, P = .0004). Overall survival was lower in the CA-VTE group than in patients without cancer (P < .0001). Black patients with CA-VTE had lower proportion of PE (52.3% vs 67.1%, P = .05) but had decreased survival (P < .0003) in comparison with White patients.

Conclusion

Future studies may be needed to continue to evaluate local and national VTE data to improve VTE prevention strategies and CA-VTE outcomes.

Background

Congenital fibrinogen disorders are classified based on both fibrinogen levels and the clinical phenotype. For dysfibrinogenemia, normal fibrinogen levels are typical.

Key Clinical Question

We highlight the importance of comprehensive thrombotic risk assessment, including lipoprotein a (Lp[a]) and hypertriglyceridemia in association with severe thrombosis and poor wound healing in dysfibrinogenemia.

Clinical Approach

We report the case of a 42-year-old male patient with a rare congenital thrombotic-related dysfibrinogenemia (fibrinogen Naples) and multiple thrombotic episodes throughout his life and an unhealing ankle wound. Despite all thrombotic episodes and surgery, the patient had undetectable D-dimer, suggestive of fibrinolytic defect, further supported by over 4-fold elevated Lp(a) levels. The last arterial thrombosis was preoperatively managed by plasma exchange, antithrombotics, and thereafter continued fibrinogen replacement therapy, under which the chronic wound has healed.

Conclusion

The combination of thrombogenesis, abnormal fibrinogen, and high Lp(a) levels is a clinical and research topic deserving more attention.

Background

Patient-reported outcomes measurement information system (PROMIS) measures can be used to measure patient-reported outcomes. PROMIS measures, including computer adaptive tests (CATs) and short forms, have demonstrated the ability to adequately assess outcomes in patients with hemophilia. It is, however, unclear if PROMIS measures are suitable for patients with von Willebrand disease (VWD), inherited platelet function disorders (IPFDs), and rare bleeding disorders (RBDs).

Objectives

To evaluate the feasibility, measurement properties, and relevance of PROMIS measures in adults with VWD, IPFDs, and RBDs.

Methods

In this cross-sectional multicenter study, adults with VWD, IPFDs, and RBDs completed 9 PROMIS measures and the Short Form-36 version 2 (SF-36v2) electronically. Feasibility was determined by the number of completed items and floor/ceiling effects. Measurement properties included construct validity based on a multitrait–multimethod analysis and reliability using the reliability coefficient and greatest lower bound. Relevance was evaluated based on comparison with the Dutch general population.

Results

In total, 111 patients (median age, 57 years [IQR, 44-67]; 60% VWD, 16% IPFD, 24% RBD) participated. Mean number of items answered varied from 5.3 to 8.7 (range, 4-12) per PROMIS CAT in patients with VWD. Construct validity was supported for all CATs and all instruments had a good reliability (≥0.70). The PROMIS measures had less ceiling effects than the SF-36v2.

Conclusion

The PROMIS measures are a feasible, valid, and reliable alternative for the SF-36v2 in patients with primarily nonsevere forms of VWD. The relevance of the selected measures was limited. Additional research is necessary to evaluate the PROMIS measures in adults with IPFDs and RBDs.