Krumholz et al developed a simple 7-item risk model for predicting survival in older adults hospitalized with acute myocardial infarction (AMI). This model can be used by hospitals to compare outcomes. The authors are from Yale University,
NOTE: Another risk model by Krumholz for elderly AMI survivors (dealing with 1 year mortality rate after the AMI) is reported in 06.08.28.
Patient selection: adults >= 65 years of age with AMI
Outcome: in-hospital mortality
Parameters identified on logistic regression:
(1) age
(2) history of cardiac arrest
(3) location of infarction
(4) systolic blood pressure in mm Hg on admission
(5) white blood cell count, in thousands per µL
(6) serum creatinine in mg/dL
(7) congestive heart failure (either clinical or radiographic)
|
Parameter
|
Finding
|
Points
|
|
age
|
age in years
|
(age in years)
|
|
history of cardiac arrest
|
no
|
0
|
|
|
yes
|
1
|
|
location of AMI
|
anterior
|
1
|
|
|
lateral
|
1
|
|
|
other
|
0
|
|
systolic blood pressure
|
< 70 mm Hg
|
70
|
|
|
70 to 200 mm Hg
|
(systolic BP)
|
|
|
> 200 mm Hg
|
200
|
|
white blood cell count
|
WBC count per µL
|
((WBC count) / 1000)
|
|
serum creatinine
|
< 0.6 mg/dL
|
0.6
|
|
|
0.6 to 2.5 mg/dL
|
(serum creatinine)
|
|
|
> 2.5 mg/dL
|
2.5
|
|
congestive heart failure
|
no
|
0
|
|
|
yes
|
1
|
X =
= (0.05 * (points for age)) + (1.50 * (points for cardiac arrest)) + (0.38 * (points for AMI location)) - (0.02 * (points for systolic BP)) + (0.05 * (points for WBC count)) + (0.72 * (points for serum creatinine)) + (0.43 * (points for CHF)) - 5.26
probability of mortality =
= 1 / (1 + EXP((-1) * X))
