Age‐adjusted D‐dimer cut‐off levels to rule out venous thromboembolism in patients with non‐high pre‐test probability: Clinical performance and cost‐effectiveness analysis

Abstract

Background: As aging was found to be associated with increased D-dimer levels, the question arose whether D-dimer measurement was useful in the diagnostic strategy of venous thromboembolism (VTE) in elderly patients. Aim of the study:To compare retrospectively the performance of six diagnostic strategies based on the three-level Wells scores and various cut-off levels for D-dimer, evaluated using the HemosIL D-Dimer HS 500 assay, in a derivation cohort of 644 outpatients with non-high pretest probability (PTP) of VTE. The clinical usefulness of the best-performing strategy was then confirmed in a multicenter validation study involving 1255 consecutive outpatients with non-high PTP. Results:The diagnostic strategy based on the age-adjusted cut-off level calculated by multiplying the patient's age by 10 above 50 years was found to perform the best in the derivation study with a better sensitivity-to-specificity ratio than the conventional strategy based on the fixed cut-off level (500 ng/ml), a higher specificity and a negative predictive value (NPV) above 99%. Such an increase in test specificity was confirmed in the validation cohort, with the NPV remaining above 99%. Taking into account the local reimbursement rates of diagnostic tests, using this strategy led to a 6.9% reduction of diagnostic costs for pulmonary embolism and a 5.1% reduction for deep vein thrombosis, as imaging tests would be avoided in a higher percentage of patients. Conclusion:The diagnostic strategy of VTE based on the age-adjusted cut-off level for D-dimer in patients over 50 years was found to be safe, with NPV above 99%, and cost-effective.

Markers of neutrophil activation and neutrophil extracellular traps in diagnosing patients with acute venous thromboembolism: A feasibility study based on two VTE cohorts

“…Using age-adjusted cut-offs [ 10 ] we calculated study specific sensitivity, 1.00 and 0.97, and specificity, 0.60 and 0.67, for VTE in VEBIOS ER and DFW-VTE respectively. These findings are in line with the results from prior studies in similar settings [ 29 ].…”

“…DFW-VTE respectively. These findings are in line with the results from prior studies in similar settings [29].…”

Age‐adjusted D‐dimer, clinical pre‐test probability‐adjusted D‐dimer, and whole leg ultrasound in ruling out suspected proximal and calf deep venous thrombosis

“…In 688 patients from China, the Innovance D‐dimer with an age‐adjusted cut‐off value combined with the Wells PTP score had a specificity of 67% and a NPV of 99% 28 . Recently, De Pooter et al confirmed that the diagnostic strategy for VTE based on age‐adjusted cut‐off level for D‐dimer in patients over 50 years of age was safe and cost‐effective, with an NPV above 99% 29 ; however, again, there were only 173 patients with suspected DVT. Until now, studies on age‐adjusted cut‐off levels for D‐dimer have enrolled only a few patients with suspected DVT.…”

Age-Related Changes in Clinical and Analytical Variables in Chronic Hemodialyzed Patients

“…For instance, the use of different hemoglobin cutoff levels for the (re)definition of anemia in elderly populations is highly debated [ 8 ]. The same applies to D-dimer values in diagnosing deep vein thrombosis in older patients [ 9 ].…”