Risk Score of Daly et al for Predicting the Risk of Death or Myocardial Infarction in One Year for a Patient with Stable Angina

 

Parameters:

(1) comorbidity

(2) diabetes mellitus

(3) angina score (based on the Canadian Cardiovascular Society classification, see 37.06.03)

(4) duration of symptoms in months

(5) ventricular function

(6) resting ECG

 

Comorbidities include:

(1) previous cerebrovascular event (stroke, other)

(2) hepatic disease (cirrhosis, chronic hepatitis, elevation of transaminases >= 3 times upper limit of normal)

(3) peripheral vascular disease (claudication at rest or with exertion, amputation for arterial insufficiency, vascular surgery, aortic aneurysm, evidence of impaired arterial flow)

(4) chronic renal failure (chronic dialysis, renal transplantation, serum creatinine > 200 µmol/L or > 2.26 mg/dL)

(5) chronic respiratory disease (therapy with bronchodilator, FEV1 < 75% of predicted, PaO2 < 60%, PaCO2 > 50%)

(6) chronic inflammatory disease (rheumatoid arthritis, SLE, polymyalgia rheumatica, other connective tissue disease)

(7) malignancy (diagnosis of malignancy within 1 year or active malignancy)

 

Parameter	Finding	Points
comorbidity	none	0
	>= 1	86
diabetes mellitus	absent	0
	present	57
angina score	Class I	0
	Class II	54
	Class III	91
duration of symptoms	>= 6 months	0
	< 6 months	80
ventricular function	normal	0
	abnormal	114
resting ECG	ST depression or T wave inversion	34
	neither	0

 

where:

• A person with Class IV angina would not have stable disease.

 

total score =

= SUM(points for all 6 factors)

 

Interpretation:

• minimum score: 0

• maximum score: 462

• The higher the score the greater the risk of death and/or myocardial infarction within one year.

 

The table for converting score to risk is in Table 7, which is only available online (see bmj.bmjjournals.com/cgi/content-nw/full/332/7536/262/TBL7). The data when plotted in MINITAB can be approximated by 2 equations:

 

For scores from 0 to 250:

 

risk in percent as a whole number =

= (-0.000018 * ((score)^2)) + (0.008363 * (score)) + 0.5418

 

For scores from 250 to 462:

 

risk in percent as a whole number =

= (0.000001 * ((score)^3)) - (0.000357 * ((score)^2)) + (0.06531 * (score)) - 1.814