Final answer:
Aspirin is the first agent to significantly prevent CHD and death by reducing the risk of heart attack in high-risk individuals.
Step-by-step explanation:
The first agent to significantly prevent CHD and death is aspirin.
In those at increased risk for coronary artery disease, aspirin has been shown to reduce the risk of myocardial infarction (heart attack) without changing the overall risk of death. It is recommended for high-risk individuals, such as men older than 90, postmenopausal women, and younger persons with risk factors like hypertension, diabetes, or smoking.
Aspirin therapy may be considered for adults with a 5-year risk of ≥ 3%. However, it's important to consult with a healthcare professional before starting aspirin therapy to determine if it's appropriate.