Pulmonary embolism · Ruling out pulmonary embolism
Age-adjusted D-dimer cutoff levels to rule out pulmonary embolism
| Design | Multicentre prospective management study |
|---|---|
| Treatment | Age-adjusted D-dimer cutoff of age × 10 µg/L in patients over 50 |
| Control | Fixed D-dimer cutoff of 500 µg/L |
| Population | 3346 patients with suspected pulmonary embolism, prevalence of PE 19% |
| Follow-up | 3 months |
| Primary endpoint | Failure rate — venous thromboembolism during follow-up after exclusion |
| Result | Among 2898 patients with non-high clinical probability, 817 (28.2%) had D-dimer below 500 µg/L and 337 (11.6%) fell between 500 µg/L and their age-adjusted cutoff. The 3-month failure rate in that intermediate band was 1 of 331 (0.3%, 95% CI 0.1% to 1.7%). In patients 75 or older with non-high probability, the age-adjusted cutoff raised the proportion in whom PE could be excluded from 6.4% to 29.7% with no additional false negatives. |
| Secondary endpoints | Proportion of older patients in whom imaging was avoided |
Compared with a fixed D-dimer cutoff of 500 µg/L, the combination of pretest clinical probability assessment with age-adjusted D-dimer cutoff was associated with a larger number of patients in whom PE could be considered ruled out with a low likelihood of subsequent clinical venous thromboembolism.
The trial authors, in the published abstract
Solves a specific and common problem: D-dimer rises with age, so the fixed threshold excludes almost nobody over 75. Raising it turned a useless test into a useful one in exactly the group most likely to be harmed by contrast and radiation. Superseded in many units by YEARS or PEGeD, which achieve the same end differently.
Righini M, Van Es J, Den Exter PL, et al. Age-adjusted D-dimer cutoff levels to rule out pulmonary embolism: the ADJUST-PE study. JAMA 2014 Mar 19;311(11):1117-24.