This study aimed to determine a new D-dimer cut-off value for excluding pulmonary embolism (PE) in patients presenting with acute exacerbation of chronic obstructive pulmonary disease (COPD). The study found that D-dimer levels are generally higher in COPD exacerbation patients compared to healthy controls. A D-dimer value of 2348 μg/mL was determined to be the optimal cut-off, with a sensitivity of 90.9% and specificity of 77.8% for excluding PE. The study concluded that using this new D-dimer cut-off value in combination with the revised Geneva score can help exclude PE and avoid unnecessary imaging tests in COPD exacerbation patients.

1. Acute exacerbation of COPD
with pulmonary embolism:
a new D-dimer cut-off value
Hesham A. AbdelHalim
Respiratory medicine department, Faculty of medicine, Ain Shams University,
Cairo, Egypt.
Heba H. AboElNaga
Respiratory medicine department, Faculty of medicine, October 6 University,
Giza, Egypt.
Egypt. J. Chest Dis. Tuberc. 2017;
http://dx.doi.org/10.1016/j.ejcdt.2017.01.008

2. Background
The clinical symptoms and signs of
chronic obstructive pulmonary disease
(COPD) exacerbation and pulmonary
embolism (PE) may overlap; D-dimer is
proven to be higher in patients suffering
from COPD exacerbation.

3. Objective
To obtain a new cut-off value of D-dimer in
subjects with exacerbation of COPD for
prospecting those with PE and to avoid
unnecessary imaging or contrast-
enhanced investigations.

4. METHODS
• The study included 83 male subjects who were recruited from
the inpatient departments of respiratory medicine of Ain
Shams University and October 6 University Hospitals.
• The subjects were diagnosed with acute exacerbation of
COPD based on clinical manifestations according to the
Anthonisen criteria.
• COPD was confirmed based on clinical manifestations and
spirometry according to the criteria of the 2015 Global
Initiative for Obstructive Lung Disease.
• Thirty healthy subjects were recruited from the health check-
up programme department of the October 6 University
Hospital as a control group.

5. Exclusion criteria
• Any Coagulation Disorders.
• Haematological Diseases.
• Hepatic Or Renal Diseases.
• Recent Myocardial Infarction.
• Receiving Oral Anti-coagulant Or Anti-platelet Remedy.
• Proven Malignancies.
• Any Collagen Vascular Diseases.
• Surgery Or Transfusion Of Blood Or Blood Component In
The Previous 3 Months.

6. The following data were collected from all
participating subjects:
• Full Medical Histories
• Anthropometric Data, Including Body Weight, Height, and
calculated Body Mass Index (BMI)
• Smoking History
• Chest Radiography
• Electrocardiogram
• Arterial Blood Gas Analysis
• Pre- and Post-bronchodilator Spirometry
• Kidney Function Tests
• Serum D-dimer, Calculated Age-adjusted D-dimer
• Revised Geneva Scores, and CTPA.

7. Revised Geneva Score
Variable Score
Age 65 years or over 1
Previous DVT or PE 3
Surgery or fracture within 1 month 2
Active malignant condition 2
Unilateral lower limb pain 3
Hemoptysis 2
Heart rate 75 to 94 beats per minute 3
Heart rate 95 or more beats per minute 5
Pain on deep palpation of lower limb and
unilateral edema
4
The score obtained relates to probability of PE:
•0 - 3 points indicates low probability (8%)
•4 - 10 points indicates intermediate probability (28%)
•11 points or more indicates high probability (74%)

8. Probability for pulmonary embolism was obtained
from the revised Geneva score for each subject,
following which the participants were classified
into three groups:
• Group 1: Low probability (31 subjects)
• Group 2: Intermediate probability (42 subjects)
• Group 3: High probability (10 subjects).

9. RESULTS

10. Table (1): data description and comparison between the total COPD subjects
and control subjects.
Mean± SD Control p
Age (years) 56.18± 11.15
54.90± 7.88 .56
Smoking (Pack. Years) 31.10± 17.29 31.10± 4.75 .999
BMI (kg/ m2) 19.93± 1.999
19.35± 2.18 .19
CAT 22.55± 8.05 - -
mMRC 3.45± 1.33 - -
Exacerbations (/year) 3.24± 2.099 - -
Hospitalizations (/year) 2.23± 1.92 - -
r-Geneva score 4.98± 4.01 - -
D-Dimer (µg/ ml) 3123.39± 920.43 361.29± 77.88 < .001
Data are presented
as mean± SD
BMI; body mass
index, CAT; COPD
assessment test,
mMRC; moidified
Medical Research
Council, r-Geneva
score; revised
Geneva score.

11. Table (2):
data
description
and
compariso
n between
the 3
COPD
subgroups
and the
control
group.
Low probability Intermediate
probability
High probability Control p
Ƒ (%) 31 (37.3%) 42 (50.6%) 10 (12.0%) 30
Age (years) 53.58± 10.33 57.93± 11.62 56.90± 11.11
54.90± 7.88 .32
Smoking (pack. Years) 31.76± 16.28 31.12± 19.26 29.00± 11.97
31.10± 4.75
.97
BMI (kg/ m2) 19.55± 1.77 19.88± 1.86 21.30± 2.75
19.35± 2.18
.06
CAT 24.58± 8.43 21.71± 7.27 19.80± 9.34
- .17*
mMRC 3.10± 1.42 3.62± 1.27 3.80± 1.14
- .17*
Exacerbations (/year) 2.03± 1.30 3.69± 2.24 5.10± 1.37
- < .01*
Hospitalizations (/year) 1.06± 1.03 2.43± 1.56 5.00± 2.36 - < .01*
r-Geneva score 1.23± 1.15 5.79± 1.68 13.20± 1.55 - < .01*
D-dimer (µg/ ml) 2584.39± 900.35 3266.52± 740.74 4193.10± 386.65 361.29± 77.88 < .01
D-Dimer value
High (ƒ (%))
Low (ƒ (%))
29 (93.5%)
2 (6.5%)
34 (81%)
8 (19%)
7 (70%)
3 (30%)
< .01*
.92
-
30 (100%)
CTPA (ƒ (%))
*

12. Receiver operating characteristic (ROC) curve shows the
optimal cut-off value of 2348 µg/mL, area under the curve
(AUC) of .836, sensitivity of .909, and specificity of .778.

13. Conclusion
D-dimer levels are high in subjects having COPD
exacerbation, suggesting that a new cut-off value
is mandatory.
In this study cohort, a D-dimer value of 2348
µg/mL was determined as the new cut-off value
for excluding PE.
Moreover, combining D-dimer values with revised
Geneva score is helpful to exclude PE and avoid
unnecessary further investigations.