Korean J Med.  2013 Mar;84(3):372-378. 10.3904/kjm.2013.84.3.372.

Cut-Off Value and Factors Associated with a False Positive D-Dimer Result for Venous Thromboembolism in Koreans

• Hong MY
• Lee C
• Yoo SY
• Shin DH
• Cheong SS
• Kwon JH
• Jang WS
• Yoo SJ
• Oh KH

• KMID: 1833846
• DOI: http://doi.org/10.3904/kjm.2013.84.3.372

Abstract

BACKGROUND/AIMS
The D-dimer value is a simple blood test used to evaluate venous thromboembolism (VTE). However, due to its low specificity, another test is needed for a definite diagnosis, such as a radiographic test. We evaluate the factors associated with a false positive D-dimer test and propose a new cut-off value for detecting VTE more effectively in Koreans.
METHODS
This was a retrospective, observational study. From January 2009 to December 2009, 2,047 patients (988 men, 63 +/- 15 years) had the D-dimer value checked to evaluate VTE. The main outcome of interest was a positive D-dimer test. Odds ratio and 95% confidence intervals were determined using logistic regression analysis. The new D-dimer cut-off was evaluated using receiver operating characteristics (ROC) curves.
RESULTS
The result was positive in 1,093 patients (53%), for a false positive percentage for VTE of 95% and a false negative percentage for VTE of 1%. Significant false positive predictors for a positive D-dimer were increasing age, trauma, postoperative, acute infection, tuberculosis, stroke, malignancy, chronic renal failure, acute coronary syndrome, heart failure, and lung disease. The discriminative value of the D-dimer test was assessed using ROC curve analysis. A D-dimer value of 0.68 mg/L on admission was the best cut-off value for predicting the development of VTE with a sensitivity of 95% and specificity of 57%.
CONCLUSIONS
Many factors affect the D-dimer value and we must consider these factors before using the D-dimer value to evaluate VTE. A D-dimer value of 0.68 mg/L appears to be a good cut-off value for evaluating VTE more effectively in Koreans.

Keyword

Venous thromboembolism; Fibrin fibrinogen degradation products; False positive reactions

MeSH Terms

Acute Coronary Syndrome
False Positive Reactions
Fibrin Fibrinogen Degradation Products
Heart Failure
Hematologic Tests
Humans
Kidney Failure, Chronic
Logistic Models
Lung Diseases
Male
Odds Ratio
Retrospective Studies
ROC Curve
Sensitivity and Specificity
Stroke
Tuberculosis
Venous Thromboembolism
Fibrin Fibrinogen Degradation Products