An investigation into the range of D-dimers
Research type
Research Study
Full title
An investigation into the range of D-dimers in a normal elderly pre-operative population to determine if the negative predictive value of D-dimer for the exclusion of venous thromboembolism (VTE) should be age adjusted.
IRAS ID
240136
Contact name
Jason Mainwaring
Contact email
Sponsor organisation
Royal Bournemouth and Christchurch Hospitals
Duration of Study in the UK
0 years, 4 months, 31 days
Research summary
D-dimers are a molecule found at high levels in blood during blood clot formation which occurs during venous thromboembolism (VTE) such as deep vein thrombosis (DVT). The D-dimer assay is used in a clinical setting to help exclude VTE. The likelihood of a VTE increased with age, as does the D-dimer level. The traditional cut-off of 500ng/mL or lower comes with a high false positive rate resulting in a large number of patients requiring further intervention in the form of scanning. This is costly, involves a hospital visit and technically trained staff. It has been suggested that an age-adjusted D-dimer level of patient age x 10 could be more beneficial with a lower false positive rate and a minimal raise in false negatives. This study will investigate the D-dimer levels of a healthy elderly population to determine whether an age adjusted cut-off is appropriate, and if so, what formula should be used. The results of this study may lead to changes in clinical practice which will save NHS money and time while not compromising the health of patients.
This will be performed by requesting consent from patients for access to their results and an extra coagulation sample will be taken. This will be from the same needle as their routine pre-operative bloods. The results of these samples, and the routine samples, will be assessed for suitability for the study. If the criteria are met a D-dimer assay will be performed and the results recorded in a secure spreadsheet for statistical analysis. Once the required numbers of samples have been analysed, statistical tests will be performed and the decision to introduce an age-adjusted D-dimer cut-off will be made.REC name
North East - York Research Ethics Committee
REC reference
18/NE/0205
Date of REC Opinion
13 Jul 2018
REC opinion
Further Information Favourable Opinion