DASH Score for Prediction of Recurrent VTE Calculator

How does this DASH score for prediction of recurrent VTE calculator work?

This is a health calculator that allows clinicians and other medical professionals to assess the annual risk of venous thromboembolism based on 4 very simple to interpret criteria.

It checks the recurrence of DVT/PE based on data readily available about the patient. It has proven its reliability in patients that have already suffered an unprovoked VTE and stratifies risk in order to provide information on anticoagulation needs.

The criteria used in this DASH score for prediction of recurrent VTE calculator also gives the DASH acronym so it is very easy to remember as well.

As the study conclusions show, abnormal D-dimer findings after coagulation stopped, a male patient aged under 50 and the cause not associated with hormonal therapy are important predictors of recurrence.

DASH study findings

This is a study that was put into practice in order to set guidelines and clarify controversy around the subject of anticoagulation in patients with a history of VTE in order to prevent PE. It used 1818 patients with no other comorbidities and excluded patients with antithrombin deficiencies, that have underwent surgery, trauma or immobility as to exclude any cases of provoked VTE. This is why it should only be applied on certain patients and those with active haemorrhages are excluded.

As a risk stratification calculator, this score focuses on recurrence in the first year after the venous episode. In general VTE recurrence for 5 years is around 27% but it decreases in time. Unfortunately  the risk of bleeding complication due to prolonged anticoagulant therapy increases in time. So there was need for a score that could help the decision process and avoid unnecessarily prolonged anticoagulation therapy.

There is still criticism of the model and a lack of external validation before this study can be put in practice routinely but in low risk cases it has already proved its efficiency.

Score interpretation

The DASH score allows the clinician to decide the patient management in terms of anticoagulant therapy and how much should that be continued after the initial standard three months treatment.

For example, in the study cohort the annual VTE recurrence was 3.1% for patients with a DASH ≤1 and 9.3% for a DASH >2.

The current guidelines advise a period of at least 3 months of vitamin K antagonist treatment after a venous episode.

This suggests that in patients with a DASH score of 1 or less, anticoagulation can be stopped after 3-6 months with no significant risks. However, for scores above 2, the recurrence risk appears to be high enough as to justify continuing the therapy for an indefinite amount of time. Below are all the risk percentages based on DASH scores.

Venous thromboembolism – medical implications

VTE is a group of diseases that include DVT – deep venous thrombosis and PE – pulmonary embolism. Although common, this is yet a very serious and possibly lethal condition that can quickly develop complications and long term suffering (CTPH - chronic thromboembolic pulmonary hypertension) and appears in both hospitalized and non hospitalized patients.

Amongst the risk factors there are:

■ Heredity

■ Hypertension

■ Diabetes mellitus

■ Sedentarism

■ Immobilisation after trauma or surgery

■ Venous damage or stasis

■ Antithrombin deficiency

■ Elevated levels of factor VIII

■ Protein C or S deficiency

VTE is said to be the third most common cardiovascular disease after stroke and ACS – acute coronary syndrome and 2 out of 3 cases need medical care. Main diagnosis investigations include the sensible D-dimer assay, duplex ultrasonogaphy, contrast venography.

In regard to hemorrhage risk or pulmonary embolism there are other useful scores to be used in risk stratification such as the:

■ Wells criteria

■ Geneva score

■ POMPE C mortality risk

References

1) Tosetto A, Iorio A, Marcucci M, Baglin T, Cushman M, Eichinger S, Palareti G, Poli D, Tait RC, Douketis J. (2012) Predicting disease recurrence in patients with previous unprovoked venous thromboembolism: a proposed prediction score (DASH). J Thromb Haemost; 10(6):1019-25

2) Kearon C, Iorio A, Palareti G; Subcommittee on Control of Anticoagulation of the SSC of the ISTH. (2010) Risk of recurrent venous thromboembolism after stopping treatment in cohort studies: recommendation for acceptable rates and standardized reporting. J Thromb Haemost; 8(10):2313-5

3) Baglin T, Palmer CR, Luddington R, Baglin C. (2008) Unprovoked recurrent venous thrombosis: prediction by D-dimer and clinical risk factors. J Thromb Haemost; 6(4):577-82