Figure 2. Estimated myocardial infarctions (MIs) prevented and estimated harms of
using aspirin for 10 years in a hypothetical cohort of 1000
men
As indicated, the estimated number of MIs prevented varies with 10-year
CHD risk. The estimated harms of using aspirin vary with age. Therefore,
both 10-year CHD risk and age must be considered when determining
whether the potential harms of aspirin use outweigh the potential benefit in
terms of MIs prevented. The boldfaced numbers indicate the combinations of
10-year CHD risk and age for which the number of harms (GI bleeding and
hemorrhagic stroke) are greater than or approximately equal to the number
of MIs prevented.*
Variable |
Estimated MIs Prevented (per 1000 Men), n |
Age 45–59
Years |
Age 60–69
Years |
Age 70–79
Years |
10-year CHD risk |
|
1% |
3.2 |
3.2 | 3.2 |
2% |
6.4 | 6.4 | 6.4 |
3% |
9.6 | 9.6 | 9.6 |
4% |
12.8 | 12.8 | 12.8 |
5% |
16 | 16 | 16 |
6% |
19.2 | 19.2 | 19.2 |
7% | 22.4 | 22.4 | 22.4 |
8% | 25.6 | 25.6 | 25.6 |
9% | 28.8 | 28.8 | 28.8 |
10% | 32 | 32 |
32 |
11% | 35.2 | 35.2 | 35.2 |
12% | 38.4 | 38.4 | 38.4 |
13% | 41.6 | 41.6 | 41.6 |
14% | 44.8 | 44.8 | 44.8 |
15% | 48 | 48 | 48 |
16% | 51.2 | 51.2 | 51.2 |
17% | 54.4 | 54.4 | 54.4 |
18% | 57.6 | 57.6 | 57.6 |
19% | 60.8 | 60.8 | 60.8 |
20% | 64 | 64 | 64 |
|
Estimated Harms, n |
Type of event |
|
GI bleeding | 8 | 24 | 36 |
Hemorrhagic stroke | 1 | 1 | 1 |
* Calculations of estimated benefits and harms rely on assumptions and are
by nature somewhat imprecise. Estimates of benefits and harms, especially
at the borders of the boldfaced and non-boldfaced areas, should be considered in
the full context of clinical decision making and used to stimulate shared
decision making. The calculations in the table are based on the following
assumptions: that there is a 32% risk reduction of MIs with regular aspirin
use3 and that gastrointestinal bleeding includes serious hemorrhage,
perforation, or other complications leading to hospitalization or death. The
harm of GI bleeding in the table assumes that the risk for GI bleeding
increases with age and that the men are not taking nonsteroidal antiinflammatory
drugs, do not have upper GI pain, or do not have a history of
GI ulcer.2
Estimates are based on age and 10-year CHD risk. CHD = coronary
heart disease; GI = gastrointestinal; MI = myocardial infarction.
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