van der Meer et al developed several bleeding risk indices to predict the risk of major bleeding in patients taking oral anticoagulants. The study was based on 2 large cohorts of patients and was done in Leiden, The Netherlands.
Parameters:
(1) age of the patient in years
(2) sex of the patient (women more likely to bleed than men)
(3) target zone for anticoagulation
(4) achieved INR (the higher the INR achieved the greater the risk of bleeding)
(5) coumarin type (long acting associated with bleeding more than short acting)
|
1988 Target Zones for INR |
Low |
Middle |
High |
|---|---|---|---|
|
prophylaxis of venous thromboembolism |
2.4 |
2.9 |
3.7 |
|
treatment of venous thromboembolism |
2.8 |
3.5 |
4.8 |
|
prevention of arterial thromboembolic disease |
2.8 |
3.5 |
4.8 |
|
prevention of arterial embolism |
2.8 |
3.5 |
4.8 |
|
prosthetic heart valves |
3.2 |
4.0 |
5.3 |
|
1991 Target Zones for INR |
Low |
Middle |
High |
|---|---|---|---|
|
prophylaxis of venous thromboembolism |
2.5 |
3.0 |
3.5 |
|
treatment of venous thromboembolism |
2.5 |
3.0 |
3.5 |
|
prevention of arterial thromboembolic disease |
3.0 |
3.5 |
4.5 |
|
prevention of arterial embolism |
3.0 |
3.5 |
4.5 |
|
bioprosthetic heart valves |
3.0 |
3.5 |
4.5 |
|
mechanical heart valve |
3.6 |
4.0 |
4.8 |
|
Parameter |
Finding |
Points |
|---|---|---|
|
age in years |
< 40 |
0 |
|
|
40 – 49 |
1 |
|
|
50 – 59 |
2 |
|
|
60 – 69 |
3 |
|
|
>= 70 |
4 |
|
sex |
male |
0 |
|
|
female |
1 |
|
target zone for INR |
low |
0 |
|
|
middle |
1 |
|
|
high |
2 |
|
achieved INR |
< 2 |
0 |
|
|
>= 2 and < 3 |
1 |
|
|
>= 3 and < 4 |
2 |
|
|
>= 4 and < 5 |
3 |
|
|
>= 5 and < 6 |
4 |
|
|
>= 6 |
5 |
|
coumarin type |
long acting (phenprocoumon) |
0 |
|
|
short acting (acenocoumarol) |
1 |
incidence of major bleeding =
= EXP (X)
X from 1988 =
= (-5.05) + (0.38 * (age points)) + (0.15 * (sex points)) - (0.56 * (target range points)) + (0.35 * (achieved INR points)) - (0.62 * (coumarin type points))
X from 1991 =
= (-6.23) + (0.45 * (age points)) + (0.38 * (sex points)) - (0.015 * (target range points)) + (0.36 * (achieved INR points)) - (0.10 * (coumarin type points))
X as arithmetic mean of 1988 and 1991 =
= (-5.64) + (0.42 * (age points)) + (0.26 * (sex points)) - (0.29 * (target range points)) + (0.36 * (achieved INR points)) - (0.36 * (coumarin type points))
where:
• X as arithmetic mean = ((X from 1988) + (X from 1991)) / 2
abbreviated X =
= (-5.64) + (0.42 * (age points)) + (0.36 * (achieved INR points))
Purpose: To estimate the risk for major bleeding in a patient taking oral anticoagulants.
Specialty: Hematology Oncology, Clinical Laboratory, Pharmacology, clinical
Objective: risk factors, laboratory tests
ICD-10: R58,
