Performance of age‐adjusted D‐dimer cut‐off to rule out pulmonary embolism

Abstract

Summary: Background: Age-adjusted D-dimer cut-off has recently been proposed to increase D-dimer usefulness in older patients suspected of pulmonary embolism (PE). Objective: We externally validated this age-adjusted D-dimer cutoff using different D-dimer assays in a multicenter sample of emergency department patients. Methods: Secondary analysis of three prospectively collected databases (two European, one American) of patients suspected of having PE. D-dimer performance for ruling out PE was assessed by calculating negative likelihood ratio (nLR) for D-dimer with age-adjusted D-dimer cut-off (< age · 10 in patients over 50 years) and with conventional cut-off (< 500 lg dL ). Test efficiency was assessed by the number needed to test (NNT) to rule out PE in one patient. Results: Among 4537 patients included, overall PE prevalence was 10.1%. In the overall population, nLR was 0.06 (95% confidence interval, 0.03-0.09) with conventional cut-off and 0.08 (0.05-0.12) with age-adjusted cut-off. Using age-adjusted cut-off, nLR was 0.08, 0.09 and 0.06 for Vidas Ò , Liatest Ò and MDA Ò assays, respectively. Use of age-adjusted cut-off produced a favorable effect on NNT in the elderly; the greatest decrease was observed in patients > 75 years: NTT halved from 8.1 to 3.6. The proportion of patients over 75 years with normal D-dimer was doubled (27.9% vs. 12.3%). Conclusions: Our study shows that age-adjusted D-dimer had low nLR, allowing its use as a rule-out PE strategy in non-high pretest clinical probability patients, as well as using Vidas Ò , Liatest Ò or MDA Ò assays. This age-adjusted cut-off increased clinical usefulness of D-dimer in older patients. A large prospective study is required to confirm these results.

Age-adjusted D-dimer excludes pulmonary embolism and reduces unnecessary radiation exposure in older adults: retrospective study

“…Three studies incorporating seven cohorts of patients with suspected PE have addressed an age-adjusted D-dimer threshold. Two of these cohorts used a Wells score ≤4,7 four an RGS ≤107 8 while one used a simplified RGS ≤4 or a Wells score ≤49 (table 3). The prevalence of PE in these studies ranged from 10.1% to 20.7%.…”

“…Douma et al 17 have validated the two-category RGS in a cohort of 807 consecutive patients with suspected PE and found only 1 PE among 185 patients who were PE unlikely and had a normal D-dimer. For this reason, we chose to compare the efficacy and safety of two clinical risk categories: ≤5 as recommended by Douma et al 17 and recently endorsed by BMJ Best Practice;11 and ≤10 in keeping with the published work on age-adjusted D-dimer 7 8…”

“…Using the RGS, we considered a patient as being unlikely to have PE by two different categories of clinical risk: first as RGS ≤5 as recommended by BMJ Best Practice11 and others;9 and second as RGS ≤10, which was the cutpoint used in two of the three published studies to have assessed the pros and cons of an age-adjusted D-dimer 7 8. We derived confidence intervals for binomial proportions using the Clopper-Pearson method12 and R V.3.2.4 ( R Core Team.…”

Pulmonary embolism: clinical guidelines of European Society of Cardiology (2014).The Task Force of the European Society of Cardiology for diagnosis and management of pulmonary embolism

“…Недавно получены доказательства о не обходимости коррекции порогового значения D ди мера соответственно возрасту больного [120,121]. В метаанализе такое пороговое значение (возраст × 10 мкг / л для больных старше 50 лет) позволило повысить специфичность с 34 до 46 % при сохране нии чувствительности выше 97 % [122].…”

Diagnosis and management of pulmonary embolism in the elderly

“…The question of a higher D-dimer cut-off in elderly patients was raised a decade ago [34], but studies confirming the potential security of such a strategy by retrospectively applying age-adjusted cut-offs to large prospective cohorts of consecutive patients with suspected VTE were published between 2010 and 2012 [35][36][37][38][39]. A recent systematic review and meta-analysis of studies in patients with suspected VTE (PE and DVT) showed a dramatic decrease of the pooled specificity from 66.8% (95% CI 61.3-72) in patients b50 years to 14.7% (95% CI 11.3-18.6) in patients N80 years with the conventional D-dimer cut-off [40].…”