The Diagnostic Efficacy of Age-Adjusted D-Dimer Cutoff Value and Pretest Probability Scores for Deep Venous Thrombosis

Are the latest point-of-care D-dimer devices ready for use in general practice? A prospective clinical evaluation of five test systems with a capillary blood feature for suspected venous thromboembolism

INTRODUCTION

We evaluated clinical performance of five novel point-of-care (POC) D-dimer devices with a capillary finger stick feature for predicting venous thromboembolism (VTE) in general practice: Exdia TRF Plus (E), AFIAS-1® (A), Standard F200® (S), LumiraDx™ (L) and Hipro AFS/1® (H).

MATERIALS AND METHODS

Primary care patients with a low suspicion of a VTE were asked to consent to (i) draw additional venous blood samples, (ii) perform a capillary POC D-dimer test, (iii) approach their general practitioner afterwards for clinical outcomes. Venous plasma samples were processed on all POC devices and a laboratory-based assay (STA-Liatest®D-Di PLUS assay). Results were compared with clinical outcomes to generate performance characteristics. Capillary and venous blood results were used for a matrix comparison.

RESULTS

Venous plasma samples from 511 participants, of whom 57 had VTE, were used for clinical performance analyses. Areas under Receiving Operating Characteristic Curves ranged from 0.90 (95 % CI: 0.86-0.94) (H) to 0.93 (0.90-0.96) (E). All false-negative rates were below 1.4 % (95 % CI: 0.5 %-3.4 %). Matrix comparison demonstrated correlation coefficients ranging from r = 0.11 (95 % CI: -0.15-0.36) (H) to r = 0.94 (0.90-0.97) (A) with concordance percentages ranging from 71.4 % (applying a D-dimer cutoff of 500 ng/mL) (H) to 100 % (applying an age-dependent D-dimer cutoff) (A).

CONCLUSIONS

Clinical performance of the POC D-dimer devices for predicting a VTE in low-risk patients was comparable to that of a laboratory-based assay. However, our results indicate that the finger stick feature of certain devices should be further improved. (NL71809.028.19.).

Age-adjusted D-Dimer Thresholds Combined with the Modified Wells Score as a Predictor of Lower Extremity Deep Venous Thrombosis

BACKGROUND

Neurosurgical patients are at an increased risk of deep venous thrombosis (DVT), which, if not properly managed, can lead to pulmonary embolism. This study aimed to investigate the accuracy of age-adjusted D-dimer thresholds combined with the modified Wells score as a predictor for lower extremity DVT diagnosis.

METHODS

We conducted a study among patients aged >50 years with suspected lower extremity DVT in the neurosurgery intensive care unit between December 2019 and December 2020. Receiver operating characteristic curve analysis was performed to examine the diagnostic capacity of age-adjusted D-dimer combined with the modified Wells score.

RESULTS

A total of 233 participants, with an average age of 71.81 ± 12.59 years, were enrolled in the study. The mean D-dimer levels were 0.73 ± 0.39 mg/L. Among the participants, 57 (57.9%, 33 males) were diagnosed with DVT. The age-adjusted D-dimer combined with the modified Wells score had the highest area under the curve for diagnosing lower extremity DVT compared to D-dimer and age-adjusted D-dimer alone, with an AUC of 0.858. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the age-adjusted D-dimer combined with the modified Wells score for DVT diagnosis were 78.95%, 80.68%, 57%, 92.2%, and 80.26%, respectively. When analyzing subgroups, the accuracy was 79.55% for participants with cerebral hemorrhage, 81.69% for those with craniocerebral injury, 74.99% for participants with intracranial infection, and 88.89% for those with craniocerebral tumor.

CONCLUSION

The combination of the age-adjusted D-dimer thresholds with the modified Wells score might effectively predict lower extremity DVT.

The Impact of D-Dimer on Postoperative Deep Vein Thrombosis in Patients with Thoracolumbar Fracture Caused by High-Energy Injuries

Objective

To investigate the dynamic variation of D-dimer and to evaluate the efficacy and accuracy of D-dimer level in patients with thoracolumbar fractures caused by high-energy injuries.

Methods

A total of 121 patients with thoracolumbar fractures caused by high-energy injuries were retrospectively identified and included in this study. There were 83 males and 38 females, with an average age of 48.6 ± 11.2 years. All patients were treated with either screw fixation surgery or decompression fixation surgery. The D-dimer levels were measured 1 day before surgery and on the first, third, and fifth days after surgery. The dynamic variation of D-dimer and the effects of risk factors on D-dimer levels were analysed. A receiver operating characteristic (ROC) curve analysis was performed and the appropriate D-dimer cut-off level was determined for deep vein thrombosis (DVT) screening.

Results

Due to a trough on the third day, D-dimer levels grew in an unsustainable manner following surgery (P < 0.001). Patients with the operation time >120 min (P = 0.009) and those with an American Spinal Injury Association (ASIA) score A-C (P < 0.001) had higher D-dimer levels. The area under the curve of D-dimer was the greatest on the third day. Applying stratified cut-off values did not change the sensitivity, specificity and negative predictive value in the group with an operation time >120 min, and ASIA score A-C group.

Conclusions

D-dimer levels elevated with fluctuation in patients with thoracolumbar fractures caused by high-energy injuries after surgery. Both operation time and ASIA score had an impact on D-dimer levels. Regarding DVT diagnoses, the diagnostic value of D-dimer was highest on the third day postoperatively, and stratified cut-off values by these two factors did not show better diagnostic efficacy compared with a collective one.

Diagnostic Performance of the Caprini Risk Assessment Model Combined With D-Dimer for Preoperative Deep Vein Thrombosis in Patients With Thoracolumbar Fractures Caused by High-Energy Injuries

OBJECTIVE

To assess the validity of the Caprini risk assessment model (RAM) in risk stratification for deep vein thrombosis (DVT) and to investigate the diagnostic value of Caprini score combined with D-dimer in predicting DVT.

METHODS

This study involved 429 patients with thoracolumbar fractures caused by high-energy injuries between October 2016 and November 2019. All patients were treated surgically and had a mean age of 45.3 ± 11.4 years. Patients were risk-stratified using the 2013 Caprini RAM. Mechanical and chemical prophylaxis were used for DVT. Duplex ultrasound of both lower extremities was performed before surgery.

RESULTS

Of the 429 patients, 62 (14.45%) developed DVT. The incidence of preoperative DVT was correlated with Caprini score according to risk stratification(χ² = 117.4, P < 0.001). Based on the original Caprini RAM, all the patients scored in the highest risk category (score ≥5). Further substratification showed that the majority (277 of 429, 64.57%) of the patients were in the Caprini score range 7-8 and the risk of preoperative DVT was significantly higher among patients with Caprini score >10. The area under the receiver operating characteristic curve of Caprini score and D-dimer was 0.816 and 0.769 when Caprini score >8 or D-dimer >1.81mg/L was considered the criterion of predicting the risk of DVT. When combining the 2 variables, the area under the ROC curve can increase to 0.846.

CONCLUSIONS

The Caprini RAM is an effective and reliable DVT risk stratification tool in patients with thoracolumbar fractures caused by high-energy injuries. Caprini score >8 or D-dimer >1.81 mg/L may predict the occurrence of preoperative DVT and the Caprini score combined with D-dimer exhibit better diagnostic performance.

Prognostic Value of D-Dimer in Younger Patients with Pulmonary Embolism

In patients with pulmonary embolism (PE), the D-Dimer assay is commonly utilized as part of the diagnostic workup, but data on D-Dimer for early risk stratification and short-term mortality prediction are limited. The purpose of this study was to determine D-Dimer levels as a predictive biomarker of PE outcomes in younger (<50 years of age) compared to older patients. We conducted retrospective analysis for 930 patients diagnosed with PE between 2015 and 2019 as part of the Serbian University Multicenter Pulmonary Embolism Registry (SUPER).All patients had D-Dimer levels measured within 24 hours of hospital admission. The primary outcome was mortality at 30 days or during hospitalization. Patients were categorized into two groups based on age (≤ 50 and >50 years of age). Younger patients constituted 20.5% of the study cohort. Regarding all-cause mortality, 5.2% (10/191)of patients died in group under the 50 years of age; the short-term all-causemortality was 12.4% (92/739) in older group.We have found that there was significant difference in plasma D-Dimer level between patients ≤ 50 years of age and older group (>50), p= 0.006.D-Dimer plasma level had good predictive value for the primary outcome in younger patients (c-statistics 0.710; 95% CI, 0.640-0.773; p<0.031). The optimal cutoff level for D-Dimer to predict PE-cause death in patients aged > 50 years was found to be 8.8 mg/l FEU(c-statistics 0,580; 95% CI 0.544-0.616; p=0.049). In younger PE patients, D-Dimer levels have good prognostic performance for 30-day all-cause mortalityand concentrations above 6.3 mg/l FEU are associated with increased risk of death. D-Dimer in patients aged over 50 years does not have predictive ability for all-caused short-term mortality. The relationship between D-Dimer and age in patients with PE may need further evaluation.

Development and prospective validation of a novel risk score for predicting the risk of lower extremity deep vein thrombosis among multiple trauma patients

INTRODUCTION

Trauma patients have an increased risk of deep vein thrombosis (DVT). Early identification of patients with a high risk of DVT after trauma is crucial for thromboembolism prophylaxis. We aimed to develop and prospectively validate a novel risk score based on a nomogram to predict lower extremity DVT among multiple trauma patients.

MATERIALS AND METHODS

Clinical data were collected from 281 multiple trauma patients who were admitted to our trauma center within 24 h of admission from January 2016 to September 2019 to develop a novel DVT risk score. The DVT risk estimates were then calculated prospectively based on the score in a new study cohort from October 2019 to July 2020. The technique of least absolute shrinkage and selection operator (LASSO) was used to select variables for the early prediction of DVT in multiple trauma patients. The DVT risk assessment score (DRAS) was constructed by incorporating related features based on the LASSO analysis and nomogram prediction model. Further, the multiple trauma patients were divided into various risk groups according to the DRAS. The incidence of lower extremity DVT was compared between groups and the discrimination of the DRAS was assessed using the area under the curve (AUC).

RESULTS

Based on the LASSO method, seven variables (age, injury severity score, body mass index, lower extremity fracture, D-dimer level, fibrin degradation products, and prothrombin time) were included in the DRAS. A total of 166 multiple trauma patients were enrolled in the prospective study. Increased risk of DVT after trauma was related to higher DRAS. The area under the receiver operating characteristic (ROC) curve for the DRAS was 0.890 (0.841-0.940) in the validation cohort. Moreover, the discriminatory capacity of the DRAS was superior to that of each variable independently and the TESS score (P < 0.05).

CONCLUSIONS

We developed and prospectively validated the DRAS as a reliable tool for predicting the risk of lower extremity DVT among patients with multiple trauma. This may help guide trauma surgeons in making sound decisions in the administration of DVT prophylaxis.

Performance of age-adjusted D-dimer values for predicting DVT before the knee and hip arthroplasty

Purpose

To compare the specificity and sensitivity of preoperative D-dimer and age-adjusted D-dimer value for predicting the incidence of the DVT preoperatively in total joint arthroplasty (TJA) patients.

Methods

We enrolled 406 patients finally above 50 years old. Everyone had done ultrasonography bedside, and D-dimer concentrations were collected before surgery. The D-dimer and age-adjusted D-dimer cut-off was calculated by multiple logistic regression and receiver operating curve (ROC) analyses.

Results

A total of 39 patients had found asymptomatic deep vein thrombosis (DVT) by ultrasonography. The age (odds ratio [OR] 1.067; p = 0.003) and D-dimer (OR 1.331; p = 0.025) were related to the existence of DVT. For conventional D-dimer and age-adjusted D-dimer value, the area under the curves (AUCs) were 0.685 (0.499–0.696) and 0.795 (0.611–0.881), respectively.

Conclusion

Compared to traditional D-dimer, age-adjusted D-dimer showed better performance in screening DVT, which was useful clinically.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-020-02172-w.