Tags

Type your tag names separated by a space and hit enter

Age-adjusted D-dimer excludes pulmonary embolism and reduces unnecessary radiation exposure in older adults: retrospective study.
Postgrad Med J. 2017 Jul; 93(1101):420-424.PM

Abstract

BACKGROUND

Patients in whom a diagnosis of pulmonary embolism (PE) is suspected and whose D-dimers are elevated frequently require CT pulmonary angiogram (CTPA) for diagnosis. Because D-dimer rises with age, an age-adjusted D-dimer threshold may prevent unnecessary radiation exposure from CTPA in older patients.

OBJECTIVE

To determine the efficacy and safety of implementing an age-adjusted D-dimer threshold to exclude PE.

DESIGN, SETTINGS AND PATIENTS

Retrospective comparison of conventional and age-adjusted D-dimer thresholds in 1000 consecutive patients who had both D-dimer and CTPA.

MAIN OUTCOME MEASURES

Conventional and age-adjusted D-dimer thresholds for excluding PE were <250 ng/mL and 5× age for patients older than 50 years, respectively. We defined patients as unlikely to have PE using the revised Geneva score (RGS) and two different categories of clinical risk: RGS ≤5 and RGS ≤10.

RESULTS

We diagnosed PE by CTPA in 244 (24.4%) patients. 3/86 patients (3.5%) whose D-dimer was below the conventional threshold of 250 ng/mL had PE (RGS 3, 9 and 14), all of which were judged to be light clot load (group 1). 3/108 patients (2.8%) whose D-dimer lay between 250 ng/mL and the age-adjusted threshold had PE (RGS 6, 8 and 9), all of which were again judged to be light clot load (group 2). 62/108 group 2 patients with RGS ≤5 were considered unlikely to have PE as were 102/108 using the RGS clinical risk category ≤10. None of the 62 patients with RGS ≤5 had PE while 3/102 patients with RGS ≤10 had PE. 236/806 patients (29.3%) whose D-dimer was above the age-adjusted threshold had PE (group 3).

CONCLUSIONS

In a consecutive series of 1000 patients, an RGS ≤5 and an age-adjusted D-dimer would have led to 62 fewer CTPA at a cost of no missed PEs.

Authors+Show Affiliations

Medical Unit, Dumfries and Galloway Royal Infirmary, Dumfries, UK.Robertson Centre for Biostatistics, University of Glasgow, Glasgow, UK.Department of Haematology, Aberdeen Royal Infirmary, Aberdeen, UK.Department of Radiology, Dumfries and Galloway Royal Infirmary, Dumfries, UK.Medical Unit, Dumfries and Galloway Royal Infirmary, Dumfries, UK.

Pub Type(s)

Journal Article

Language

eng

PubMed ID

27941007

Citation

Nobes, Jennifer, et al. "Age-adjusted D-dimer Excludes Pulmonary Embolism and Reduces Unnecessary Radiation Exposure in Older Adults: Retrospective Study." Postgraduate Medical Journal, vol. 93, no. 1101, 2017, pp. 420-424.
Nobes J, Messow CM, Khan M, et al. Age-adjusted D-dimer excludes pulmonary embolism and reduces unnecessary radiation exposure in older adults: retrospective study. Postgrad Med J. 2017;93(1101):420-424.
Nobes, J., Messow, C. M., Khan, M., Hrobar, P., & Isles, C. (2017). Age-adjusted D-dimer excludes pulmonary embolism and reduces unnecessary radiation exposure in older adults: retrospective study. Postgraduate Medical Journal, 93(1101), 420-424. https://doi.org/10.1136/postgradmedj-2016-134552
Nobes J, et al. Age-adjusted D-dimer Excludes Pulmonary Embolism and Reduces Unnecessary Radiation Exposure in Older Adults: Retrospective Study. Postgrad Med J. 2017;93(1101):420-424. PubMed PMID: 27941007.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Age-adjusted D-dimer excludes pulmonary embolism and reduces unnecessary radiation exposure in older adults: retrospective study. AU - Nobes,Jennifer, AU - Messow,Claudia-Martina, AU - Khan,Mohammed, AU - Hrobar,Petr, AU - Isles,Chris, Y1 - 2016/12/09/ PY - 2016/10/01/received PY - 2016/11/16/revised PY - 2016/11/20/accepted PY - 2016/12/13/pubmed PY - 2017/11/29/medline PY - 2016/12/13/entrez KW - Age-adjusted D-dimer KW - CTPA KW - D-dimer KW - Pulmonary embolism SP - 420 EP - 424 JF - Postgraduate medical journal JO - Postgrad Med J VL - 93 IS - 1101 N2 - BACKGROUND: Patients in whom a diagnosis of pulmonary embolism (PE) is suspected and whose D-dimers are elevated frequently require CT pulmonary angiogram (CTPA) for diagnosis. Because D-dimer rises with age, an age-adjusted D-dimer threshold may prevent unnecessary radiation exposure from CTPA in older patients. OBJECTIVE: To determine the efficacy and safety of implementing an age-adjusted D-dimer threshold to exclude PE. DESIGN, SETTINGS AND PATIENTS: Retrospective comparison of conventional and age-adjusted D-dimer thresholds in 1000 consecutive patients who had both D-dimer and CTPA. MAIN OUTCOME MEASURES: Conventional and age-adjusted D-dimer thresholds for excluding PE were <250 ng/mL and 5× age for patients older than 50 years, respectively. We defined patients as unlikely to have PE using the revised Geneva score (RGS) and two different categories of clinical risk: RGS ≤5 and RGS ≤10. RESULTS: We diagnosed PE by CTPA in 244 (24.4%) patients. 3/86 patients (3.5%) whose D-dimer was below the conventional threshold of 250 ng/mL had PE (RGS 3, 9 and 14), all of which were judged to be light clot load (group 1). 3/108 patients (2.8%) whose D-dimer lay between 250 ng/mL and the age-adjusted threshold had PE (RGS 6, 8 and 9), all of which were again judged to be light clot load (group 2). 62/108 group 2 patients with RGS ≤5 were considered unlikely to have PE as were 102/108 using the RGS clinical risk category ≤10. None of the 62 patients with RGS ≤5 had PE while 3/102 patients with RGS ≤10 had PE. 236/806 patients (29.3%) whose D-dimer was above the age-adjusted threshold had PE (group 3). CONCLUSIONS: In a consecutive series of 1000 patients, an RGS ≤5 and an age-adjusted D-dimer would have led to 62 fewer CTPA at a cost of no missed PEs. SN - 1469-0756 UR - https://www.unboundmedicine.com/medline/citation/27941007/Age_adjusted_D_dimer_excludes_pulmonary_embolism_and_reduces_unnecessary_radiation_exposure_in_older_adults:_retrospective_study_ L2 - https://pmj.bmj.com/lookup/pmidlookup?view=long&amp;pmid=27941007 DB - PRIME DP - Unbound Medicine ER -