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DASH Prediction Score for Recurrent VTE

Calculators  Hematology
The DASH Prediction Score for Recurrent VTE predicts a patients recurrence risk following their first unprovoked venous thromboembolism, a blood clot that is initiated in a vein. It can also assist physicians in deciding whether a patient should remain on anticoagulation therapy once they have completed a standard 3-6 month course.
D-dimer abnormal
Measured ~1 month after stopping anticoagulation
No 0
Yes 2
Age ≤50 years
No 0
Yes 1
Male patient
No 0
Yes 1
Hormone use at VTE onset (if female)
No 0
Yes -2


Measured Factor
DASH Score
Measured Factor Disease
  • Low annual risk of VTE recurrence
  • Discontinuation of anticoagulation therapy
  • High annual risk of VTE recurrence
  • Continuation of anticoagulation therapy
Measured Factor Detail
The DASH Score is utilized when deciding whether a patient with their first unprovoked venous thromboembolism is at risk for recurrence, and how long a patient should remain on anticoagulation therapy following a standard 3 - 6 month course. The DASH Score is meant to be applied to stable patients and always consider the clinical scenario before continuing or discontinuing anticoagulation therapy. With a DASH Score of ≤ 1, consider discontinuing anticoagulation. With a DASH Score of ≥ 2, consider continuing anticoagulation.
Body System
Measured Factor Low Impact
  • A DASH score of ≤ 1 is associated with a low annual risk of VTE recurrence.
  • Consider discontinuation of anticoagulation therapy in patients with a DASH score of ≤ 1.
Measured Factor High Impact
  • A DASH score of ≥ 2 is associated with a high annual risk of VTE recurrence.
  • Consider continuing anticoagulation therapy in patients with a DASH score of ≥ 2.

Result Interpretation

Ranges Ranges
  • Critical High: 200%
  • Normal: ≤ 1
  • Normal Adult Male: ≤ 1
  • Normal Adult Female: ≤ 1
  • Normal Pediatric: ≤ 1
  • Normal Neonate Female: ≤1
  • Normal Geriatric Male: ≤ 1
  • Normal Geriatric Female: ≤ 1
Result Low Conditions
  • Low annual risk of VTE recurrence
  • Discontinuation of anticoagulation therapy
Result High Conditions
  • High annual risk of VTE recurrence
  • Continuation of anticoagulation therapy
Test Limitations
First, several different D-dimer assays were used in the included studies, possibly introducing between-study heterogeneity and reducing discrinatory power. Second, despite the large patient sample, the number of recurrent VTEs was low (239, 13.1% of studied patients), possible also because of the relatively short mean observation period. Third, as meta-analysis is retrospective research, analyses are limited to the available data and we were unable to address the question of whether other potential predictors of VTE recurrence, such as residual DVT detected by venous ultrasound or ongoing symptoms of post-thrombotic syndrome, could further improve the prognostic model. Fourth, including hormone-associated VTE as unprovoked VTE may be questioned.
References: 1


Study Validation 1
Patients with a proximal unprovoked deep vein thrombosis (DVT) or pulmonary embolism (PE) who received a full course of vitamin K antagonist or direct oral anticoagulant (< 3 months) and had D-dimer measured after treatment withdrawal were eligible. The DASH score was computed on the basis of the D-dimer level after therapy withdrawal and personal characteristics at the time of the event. Recurrent VTE events were symptomatic proximal or distal DVT/PE, and were analyzed with a time-dependent analysis. Observed 12-month and 24-month recurrence rates were compared with recurrence rates predicted by the DASH model. We analyzed a total of 827 patients, of whom 100 (12.1%) had an objectively documented recurrence. As compared with the original DASH cohort, there was a greater proportion of subjects with a 'low-risk' (≤ 1) DASH score (66.3% versus 51.6%, P < 0.001). The slope of the observed versus expected cumulative incidence at 2 years was 0.71 (95% confidence interval 0.51-1.45). The c-statistic was lower for subjects aged > 65 years (0.54) than for younger subjects (0.72). These results confirm the validity of DASH prediction model, particularly in young subjects.
References: 2
Study Validation 2
Randomized controlled trials are the optimal study design to compare management strategies, including comparisons of different durations of anticoagulant therapy for venous thromboembolism (VTE). The results of randomized trials suggest that indefinite anticoagulation, rather than just 3 or 6 months of treatment, is of benefit in patients with unprovoked proximal deep vein thrombosis (DVT) or pulmonary embolism (PE). However, many physicians are reluctant to treat patients with a first unprovoked proximal DVT or PE indefinitely. First, there is concern that follow-up in the randomized controlled trials may not have been long enough to reliably determine if the benefits of indefinite anticoagulant therapy outweigh the cumulative risk of bleeding. Second, there is concern that the findings of randomized controlled trials may not reflect the risks and benefits of indefinite anticoagulant therapy in the less controlled setting of usual clinical practice. Third, even if the finishing of randomized trials accurately reflect a true overall benefit from indefinite anticoagulant therapy in usual clinical practice, many physicians believe that the magnitude of this overall benefit is not large enough to justify the burden and cost of indefinite therapy. Furthermore, as only about half of patients with a first unprovoked proximal DVT or PE will have a recurrent episode of venous thromboembolism within 10 years of stopping therapy, there is reluctance to treat all such patients indefinitely. Identification of subgroups of patients with unprovoked proximal DVT and PE who have a low risk of recurrence and subsequent validation that it is safe to stop anticoagulant therapy after 3 months of treatment in these subgroups are high priorities. Once a low-risk group has been identified or proposed, one way to validate that it is safe to stop therapy in these patients would be to randomize them to either stop or remain on indefinite anticoagulant therapy, with a view to demonstrating that indefinite therapy was not of benefit or that it was harmful. Such a randomized trial, however, would be difficult to perform (large and costly), and randomizing patients to indefinite anticoagulant therapy in order to show that such therapy is not beneficial, or is harmful, would be hard to justify. Cohort studies are an alternative and more appealing way to test the hypothesis that a predefined subgroup of patients truly has a low enough risk of recurrent VTE that stopping anticoagulant therapy is justified. The primary objective of this ISTH statement is to propose an absolute risk of recurrent VTE that is at the upper limit of acceptable, and would justifying stopping anticoagulant therapy, in patients who have completed an initial course of treatment. Cohort studies could then test the hypothesis that predefined subgroups of patients with VTE have a rate of recurrence after stopping anticoagulant therapy that is similar to, or lower than, this rate of recurrence. Secondary objectives are to suggest a standardized method for reporting risk of recurrent VTE after stopping anticoagulant therapy, and to identify study design elements that are important in cohort studies that test the validity of prediction rules for recurrent VTE. In this statement, recurrent VTE during follow-up refers to all episodes of recurrent VTE, anticipating that most (e.g. about 90%) of these episodes of recurrent VTE will be unprovoked or associated with a minor provoking factor and, therefore, would not be prevented by use of temporary VTE prophylaxis during high-risk periods (e.g. after surgery).
References: 3
Study Additional 1
Seven prospective studies that investigated an association between d-dimer, measured after stopping anticoagulation, and disease recurrence in patients with a first unprovoked VTE (proximal deep venous thrombosis, pulmonary embolism, or both) were reviewed. Patient-level databases were obtained, transferred to a central database, checked, completed with further information provided by study investigators, and pooled into a single database. 1818 patients with a first unprovoked VTE were followed for a mean of 26.9 months (SD, 19.1). A study-stratified multivariate Cox regression model, which included patient age, sex, hormone therapy use at the time of the index event, body mass index, timing of postanticoagulation d-dimer testing, and inherited thrombophilia as possible confounders, indicated that the hazard ratio for d-dimer status (positive vs. negative) was 2.59 (95% CI, 1.90 to 3.52). Only male sex had a significant effect on risk for recurrent VTE independent of d-dimer status. The Cox regression model and the log-rank test confirmed tha the risk for recurrent VTE was higher in patients with a positive d-dimer result than in those with a negative result, regardless of the timing of postanticoagulation d-dimer testing or patient age. No study- or assay-specific d-dimer effect was found, and reassessing the analysis after recoding data according to specific quantitative d-dimer cut points (500 micrograms/L and 250 micrograms/L) did not change the results. In patients with a first unprovoked VTE who have their d-dimer level measured after stopping anticoagulation, the timing of d-dimer testing, patient age, and the assay cut point used do not affect the ability of d-dimer to distinguish patients with a higher or lower risk for recurrent VTE.
References: 4
Study Additional 2
To identify patients who carry a high recurrent risk and require long-term treatment, three algorithms have been proposed to: the HERDOO2, the Vienna prediction model, and the DASH score. All identify male sex and elevated D-dimer levels as important risk factors for recurrence. However, important differences among the models should be outlined: in the HERDOO2 model, D-dimer levels are measured during anticoagulation and not after its withdrawal; furthermore, it indicates age greater than 65 as a risk factor for recurrence, whereas the DASH score attributes a higher risk to age less than 50. The Vienna model is complex for routine use. Further studies are needed to clarify these discrepancies. A management study based on D-dimer levels after anticoagulation withdrawal is ongoing and could indicate a simple way to safely manage these patients.
References: 5
Study Additional 3
I this study bibliographic databases (including MEDLINE, EMBASE and the Cochrane Library) were searched using index terms relating to the clinical field and prognosis of venous thromboembolism (VTE) recurrence risk following cessation of therapy for a first unprovoked VTE. Three separate prognostic models were identified including the HERDOO2 score, Vienna prediction model and DASH score. Quality assessment highlighted the Vienna, and DASH models were developed with generally strong methodology, but the HERDOO2 model had many methodological concerns. Further, all models were considered at least at moderate risk of bias, primarily due to the need for further external validation before use in practice.
References: 6


Alberto Tosetto
Hematologist, University of Bologne in Italy
Research Interests: Clinical hematology and vascular medicine


  1. Tosetto A, Iorio A, Marcucci M, Baglin T, Cushman M, Eichinger S, et al. Predicting disease recurrence in patients with previous unprovoked venous thromboembolism: a proposed prediction score (DASH). J Thromb Haemost. 2012 Jun;10(6):1019-25.
  2. Tosetto A, Testa S, Martinelli I, Poli D, Cosmi B, Lodigiani C, et al. External validation of the DASH prediction rule: a retrospective cohort study. J Thromb Haemost. 2017 Oct 1;15(10):1963-1970.
  3. Kearon C, Iorio A, Palareti G; Subcommittee on Control of Anticoagulation of the SSC of the ISTH. Risk of recurrent venous thromboembolism after stopping treatment in cohort studies: recommendation for acceptable rates and standardized reporting. J Thromb Haemost. 2010 Oct;8(10):2313-5. doi: 10.1111/j.1538-7836.2010.03991.
  4. Douketis J, Tosetto A, Marcucci M, Baglin T, Cushman M, Eichinger S, Palareti G, Poli D, Tait RC, Iorio A. Patient-level meta-analysis: effect of measurement timing, threshold, and patient age on ability of D-dimer testing to assess recurrence risk after unprovoked venous thromboembolism. Ann Intern Med. 2010 Oct 19;153(8):523-31. doi: 10.7326/0003-4819-153-8-201010190-00009.
  5. Poli D, Palareti G. Assessing recurrence risk following acute venous thromboembolism: use of algorithms. Curr Opin Pulm Med. 2013 Sep;19(5):407-12. doi: 10.1097/MCP.0b013e328363ed7c.
  6. Ensor J, Riley RD, Moore D, Snell KI, Bayliss S, Fitzmaurice D. Systematic review of prognostic models for recurrent venous thromboembolism (VTE) post-treatment of first unprovoked VTE. BMJ Open. 2016 May 6;6(5):e011190. doi: 10.1136/bmjopen-2016-011190.