Diagnostic accuracy of four different D-dimer assays: A post-hoc analysis of the YEARS study. Issue 201 (May 2021)

• Record Type: Journal Article
• Authors: Hamer, Henrike M.; Stroobants, An K.; Bavalia, Roisin; Ponjee, Gabrielle A.E.; Klok, Frederikus A.; van der Hulle, Tom; Huisman, Menno V.; Hendriks, Henriët A.; Middeldorp, Saskia
• Is Part Of: Thrombosis research. Issue 201(2021)
• Page Start: 18
• Page End: 22
• Publication Date: 2021-05
• Subjects: CTPA computer tomography pulmonary angiography -- DVT deep vein thrombosis -- IQR interquartile range -- NA not applicable -- NPV negative predictive value -- PE pulmonary embolism -- PPV positive predictive value -- SD standard deviation -- WHO World Health Organization; D-dimer test -- Deep vein thrombosis -- Diagnostic accuracy -- Laboratory test -- Predictive value; Thrombosis -- Periodicals; 616.135
• DOI: 10.1016/j.thromres.2021.02.003
• Languages: English
• ISSNs: 0049-3848

Abstract

Abstract: Introduction: For exclusion of pulmonary embolism (PE) clinical decision rules in combination with a D-dimer assay are applied. Currently available D-dimer assays are not standardized and it is unknown whether these differences have an impact on diagnostic management of suspected PE. Therefore, the aim is to explore differences between D-dimer assays and their impact on diagnostic outcome. Methods: Data from all patients included in the YEARS study were collected. The YEARS study is a prospective, multicentre, cohort outcome study evaluating 3462 patients with suspected PE in which four different D-dimer assays were applied (Liatest, Innovance, Tinaquant, Vidas). Median D-dimer concentrations were calculated for each D-dimer assay. Sensitivity, specificity, PPV and NPV for detection of PE of all four assays were determined in patients without YEARS items and in those with ≥1 YEARS items (i.e. symptomatic deep vein thrombosis, haemoptysis, and whether PE is the most likely diagnosis). Results: A total of 1323, 1100, 768 and 271 D-dimer concentrations were collected using the Liatest Innovance, Tinaquant and Vidas assay, respectively. Median D-dimer concentrations differed significantly between assays, with lowest values in the Tinaquant assay. In patients without YEARS items using a cutoff level of 1000 ng/mL, the NPV varied from 99, 5 to 100%. In patients with ≥1 YEARS items using a 500 ng/mL cutoff, the NPV varied from 97, 0 to 100% depending on the assay. Conclusions: The overall high NPV for all assays demonstrates the clinical value of the D-dimer assay. However, these results confirm differences between D-dimer assays, which have an impact on follow-up imaging. This emphasizes the need for standardization of D-dimer assays. Highlights: D-dimer levels differ between assays, emphasizing the need for standardization. Patients without YEARS items (i.e. low probability for PE) with D-dimer below 1000 ng/mL varied from 71% to 82%. Patients with ≥1 YEARS items (i.e. increased probability for PE) with D-dimer below 500 ng/mL varied from 15% to 29%. Differences in assays result in differences in numbers of follow-up imaging. Despite their differences, all assays show a high NPV of >97% demonstrating their clinical value.