Patient selection: age > 40 years, smoking history >= 10 pack years, pre-bronchodilator FEV1 less than 50% of predicted, 1 or more exacerbations in the past year, FEV1 to FVC ratio < 0.70
Outcome: COPD exacerbation within 6 months
Parameters::
(1) gender
(2) number of COPD maintenance medications
(3) number of exacerbations in the past year
(4) prebronchodilator FEV1 to FVC ratio
(5) reliever use, as number of inhalations per day
Maintenance medications include:
(1) long-acting beta2-agonists
(2) long-acting antimuscarinics
(3) theophylline
(4) inhaled corticosteroids
(5) short-acting beta2-agonists
(6) short-acting antimuscarinics
|
Parameter
|
Finding
|
Points
|
|
gender
|
male
|
0
|
|
|
female
|
10
|
|
number of COPD maintenance drugs
|
0 or 1
|
0
|
|
|
2
|
12
|
|
|
3
|
20
|
|
number of exacerbations in previous year
|
1
|
0
|
|
|
2
|
13
|
|
|
3 or 4
|
17
|
|
|
5 or more
|
24
|
|
FEV1 to FVC ratio
|
>= 60%
|
0
|
|
|
40 to 59%
|
17
|
|
|
< 40%
|
25
|
|
reliever use
|
< 5 inhalations per day
|
0
|
|
|
5 to 10 inhalations per day
|
10
|
|
|
> 10 inhalations per day
|
21
|
total score =
= SUM(points for all 5 parameters)
Interpretation:
• minimum score: 0
• maximum score: 100
• The higher the score the greater the risk of an exacerbation within 6 months.
percentage of patients with these findings who had an exacerbation within 6 months if treated with placebo =
= (0.004499 * ((points)^2)) + (0.3865 * (points)) + 11.02
Performance:
• The area under the ROC curve was 0.67.
