Age adjusted D-dimer

[polarbebe]

Using this where you work to rule out low risk PE in the elderly?

 

 

http://www.ncbi.nlm.nih.gov/m/pubmed/24643601/

 

Age-adjusted D-dimer cutoff levels to rule out pulmonary embolism: the ADJUST-PE study.

 

AuthorsRighini M, et al. Show all Journal

JAMA. 2014 Mar 19;311(11):1117-24. doi: 10.1001/jama.2014.2135.

 

Affiliation

Erratum in

JAMA. 2014 Apr 23-30;311(16):1694.

Abstract

IMPORTANCE: D-dimer measurement is an important step in the diagnostic strategy of clinically suspected acute pulmonary embolism (PE), but its clinical usefulness is limited in elderly patients.

 

OBJECTIVE: To prospectively validate whether an age-adjusted D-dimer cutoff, defined as age × 10 in patients 50 years or older, is associated with an increased diagnostic yield of D-dimer in elderly patients with suspected PE.

 

DESIGN, SETTINGS, AND PATIENTS: A multicenter, multinational, prospective management outcome study in 19 centers in Belgium, France, the Netherlands, and Switzerland between January 1, 2010, and February 28, 2013.

 

INTERVENTIONS: All consecutive outpatients who presented to the emergency department with clinically suspected PE were assessed by a sequential diagnostic strategy based on the clinical probability assessed using either the simplified, revised Geneva score or the 2-level Wells score for PE; highly sensitive D-dimer measurement; and computed tomography pulmonary angiography (CTPA). Patients with a D-dimer value between the conventional cutoff of 500 µg/L and their age-adjusted cutoff did not undergo CTPA and were left untreated and formally followed-up for a 3-month period.

 

MAIN OUTCOMES AND MEASURES: The primary outcome was the failure rate of the diagnostic strategy, defined as adjudicated thromboembolic events during the 3-month follow-up period among patients not treated with anticoagulants on the basis of a negative age-adjusted D-dimer cutoff result.

 

RESULTS: Of the 3346 patients with suspected PE included, the prevalence of PE was 19%. Among the 2898 patients with a nonhigh or an unlikely clinical probability, 817 patients (28.2%) had a D-dimer level lower than 500 µg/L (95% CI, 26.6%-29.9%) and 337 patients (11.6%) had a D-dimer between 500 µg/L and their age-adjusted cutoff (95% CI, 10.5%-12.9%). The 3-month failure rate in patients with a D-dimer level higher than 500 µg/L but below the age-adjusted cutoff was 1 of 331 patients (0.3% [95% CI, 0.1%-1.7%]). Among the 766 patients 75 years or older, of whom 673 had a nonhigh clinical probability, using the age-adjusted cutoff instead of the 500 µg/L cutoff increased the proportion of patients in whom PE could be excluded on the basis of D-dimer from 43 of 673 patients (6.4% [95% CI, 4.8%-8.5%) to 200 of 673 patients (29.7% [95% CI, 26.4%-33.3%), without any additional false-negative findings.

 

CONCLUSIONS AND RELEVANCE: 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.

[True Anomaly]

Good article- seems to be a well done study that fills in a lot of holes in the literature.  I like how they even note the comparison of using 6 different D-dimer assays were pretty equal in their results. 

 

To answer your question, we're not using any age-related cutoffs as of yet, and I haven't heard anyone talk about this article yet.  My thinking is our institution would want to see a US-based multicenter prospective trial be done to help validate these results.  I'd also be interested to see what Jeff Kline, one of the foremost PE/DVT experts in the US, has to say about this- he has advocated before for D-dimer cutoffs based on the trimester of pregnancy.

[jen0508]

Several of my SP's are using this now. Personally i have not used this yet

[LoRezSkyline]

I'd also be interested to see what Jeff Kline, one of the foremost PE/DVT experts in the US, has to say about this

 

Ask, and ye shall receive...

 

http://www.annemergmed.com/article/S0196-0644(13)01712-5/pdf

 

If you're on Twitter, Kline's always dropping PE/DVT pearls on there - great one to follow, @klinelab.  His latest project below - he & others are trying to advocate for a standardized, across-the-board dimer instead of the myriad tests/ranges we have now.

 

https://twitter.com/klinelab

https://twitter.com/klinelab/status/485144778846511104

[True Anomaly]

Thanks LoRez! Very helpful.  Looks like that particular method still needs further study, but overall looking good

[medic25]

This was discussed on the most recent EM:RAP. A good point is that you should have your institution develop a formal policy recognizing the age-adjusted standards. You'll have trouble defending yourself if the patient bounced back with a PE (it happens) and their d-dimer was positive according to your lab, even if it was lower than the age-adjusted figure.

[LoRezSkyline]

...and then there's this, which suggests this one might not quite be ready for prime-time just yet???

 

http://rebelem.com/update-age-adjusted-d-dimer/

 

agreed re: the above post, no way am i instituting this in my practice until it's a well-established institutional policy!!! 

[EMEDPA]

also remember the limitations of the d-dimer. it measures ACUTE products of coagulation. if someone has managed to survive with their huge PE for 2 weeks and not died their D-Dimer may be normal. we were within 5 minutes of d/c ing a guy in his 40s with chest pain from our obs unit with nl ekgs, nl enzymes, nl d-dimer, nl cxr, nl metabolic workup including tsh, and nl treadmill until one of the docs recognized that even while asleep this guy had a resting tachycardia of around 105 that had persisted for >24 hrs.

CTA showed massive b/l PEs. we covered his pain with narcs, toradol, etc while in the obs unit prior to his dx, but because his underlying physical condition was excellent he never had a poor sat, got tachypneic, or did the nl things folks do who have big PEs.