The age-adjusted D-dimer safely excludes a high number of pulmonary embolisms in combination with four different clinical decision rules

摘要

Background: Four different clinical decision rules (CDRs) (Wells score, Revised Geneva score (RGS), simplified Wells score and simplified RGS) safely exclude pulmonary embolism (PE), when combined with a normal D-dimer test. Recently, an age adjusted cut-off of the D-dimer (patient's age x 10 ig/L) greatly increased the number of patients in whom PE could safely be excluded. We validated the age-adjusted D-dimer test and assessed its performance in combination with the four CDRs in patients with suspected PE. Methods: Eight hundred and thirty-four consecutive patients with suspected PE were included of whom 414 were > 50 years (50%). The proportion of patients in whom PE could be excluded with an unlikely CDR combined with a normal age-adjusted D-dimer test was calculated and compared with the conventional D-dimer cut-off. We assessed VTE failure rates during 3-months follow-up. Results: Compared to the conventional D-dimer cut-off level, a normal age-adjusted D-dimer level substantially increased the number of patients in whom PE could be safely excluded. All CDRs performed equally well. This difference was nearly fourfold in patients > 70 years, where the Wells rule excluded more patients than the other CDRs. Conclusion: The age-adjusted D-dimer increases the number of older patients in whom PE can be safely excluded, irrespective of the Wells score or RGS, thereby avoiding unnecessary imaging tests.