Rethinking D-Dimer with Age in Mind

JAMA study shows age-adjusted cutoffs safely exclude DVT in more patients, sparing unnecessary ultrasounds

By
Olivia Anderson
January 9, 2026
3 min

Conexiant

Overview

A large multinational study demonstrates that using an age-adjusted D-dimer cutoff can safely increase the number of patients in whom deep vein thrombosis (DVT) can be ruled out without imaging. This approach particularly benefits older adults, enhancing diagnostic efficiency in emergency settings.

Background

The accurate diagnosis of DVT is crucial to prevent complications such as pulmonary embolism. Traditional D-dimer cutoffs may lead to unnecessary imaging and treatment, especially in older patients whose D-dimer levels naturally increase with age. This study explores the potential of age-adjusted thresholds to improve diagnostic accuracy and patient care.

Data Highlights

Age Group	Negative D-Dimer Results (Standard Cutoff)	Negative D-Dimer Results (Age-Adjusted Cutoff)
Overall	25%	32%
≥75 years	9%	26%

Key Findings

Age-adjusted D-dimer threshold is defined as age × 10 µg/L for patients aged 50 and older.
Among patients with non-high or unlikely clinical pretest probability, 25% had D-dimer levels below the standard cutoff.
7% of patients had D-dimer levels between the standard cutoff and their age-adjusted threshold.
No symptomatic venous thromboembolic events occurred in patients with D-dimer levels between the standard and age-adjusted thresholds during follow-up.
The use of age-adjusted cutoffs resulted in a 7% absolute increase in patients who could safely forgo imaging.
In patients aged 75 years or older, negative D-dimer results increased from 9% to 26% with the age-adjusted cutoff.

Clinical Implications

Integrating age-adjusted D-dimer thresholds into clinical practice may reduce unnecessary imaging and improve the efficiency of DVT diagnosis, particularly in older adults. Clinicians should consider this approach alongside established clinical probability assessments to enhance patient care.

Conclusion

The application of age-adjusted D-dimer cutoffs represents a significant advancement in the management of suspected DVT, particularly for older patients, promoting safer and more efficient diagnostic strategies.