Should an Elderly Woman with CAC 108 Take Aspirin 81 mg?
No, an elderly woman with a CAC score of 108 should not routinely take aspirin 81 mg for primary prevention, as current evidence shows no net benefit and increased bleeding risk in adults ≥60 years without established cardiovascular disease. 1
Age-Based Guideline Recommendations
The most recent and authoritative guidance from the U.S. Preventive Services Task Force (2022) explicitly recommends against initiating low-dose aspirin for primary prevention in adults 60 years or older (Grade D recommendation). 1 This represents a significant shift from earlier guidelines and is based on moderate certainty evidence that aspirin provides no net benefit in this age group due to increased bleeding risk that offsets any cardiovascular benefit. 1
The American Diabetes Association (2025) reinforces this position, stating that aspirin should not be prescribed for primary prevention in adults ≥60 years, regardless of cardiovascular risk, as bleeding risks outweigh benefits. 2
Understanding CAC Score of 108
A CAC score of 108 indicates moderate coronary atherosclerosis and places this patient at intermediate cardiovascular risk. 3 While some research suggests that CAC scores >100 may identify "high-risk" individuals who could theoretically benefit from aspirin, 3 this approach is not endorsed by major guideline organizations and does not override the age-based contraindication for primary prevention in elderly patients.
The critical distinction is that a CAC score of 108 does not constitute established cardiovascular disease (such as prior myocardial infarction, stroke, or revascularization), which would be the only scenario where aspirin would be clearly indicated. 4, 2
Bleeding Risk Considerations in Elderly Patients
Older adults face substantially elevated bleeding risks with aspirin therapy:
- Major bleeding occurs at rates of 4-12 per 1,000 older persons over 5 years, compared to 2-4 per 1,000 in middle-aged adults. 5, 4
- The ASPREE trial (2018) specifically studied elderly patients and found aspirin significantly increased major hemorrhage and, unexpectedly, all-cause mortality without reducing cardiovascular events. 6
- Age >70 years is itself a high bleeding risk factor, independent of other considerations. 2
When Aspirin Would Be Indicated
Aspirin 75-162 mg daily would be strongly recommended if this patient had: 4, 2
- Prior myocardial infarction
- Prior stroke or TIA
- History of coronary revascularization (PCI or CABG)
- Documented obstructive coronary artery disease on angiography
- Peripheral arterial disease with symptoms
In these secondary prevention scenarios, the benefits clearly outweigh bleeding risks even in elderly patients. 5, 2
Alternative Risk Reduction Strategies
Rather than aspirin, this patient should receive: 4
- Statin therapy if LDL-C is elevated, which has proven mortality benefit in primary prevention
- Blood pressure optimization to target <140/90 mmHg if hypertensive 5
- Lifestyle modifications including smoking cessation, Mediterranean diet, and regular physical activity
- Diabetes management if present, targeting HbA1c <7% 5
Common Pitfalls to Avoid
Do not extrapolate secondary prevention data to primary prevention. The 2007 and 2011 American Heart Association guidelines for women recommended aspirin in "high-risk" patients, but these were written before the 2018 trials (ASPREE, ASCEND, ARRIVE) demonstrated lack of benefit and increased harm in primary prevention populations. 5, 6
Do not use CAC scores alone to justify aspirin in elderly patients. While CAC scoring helps risk stratification, it does not change the fundamental age-based recommendation against aspirin initiation in those ≥60 years for primary prevention. 3, 1
Avoid the misconception that "some cardiovascular risk" equals aspirin indication. The threshold for aspirin benefit requires either established disease or, in younger adults (40-59 years), a 10-year cardiovascular risk ≥10% combined with low bleeding risk. 1 Age ≥60 years negates this consideration entirely for primary prevention.