In a hypertensive adult without prior myocardial infarction, stroke, or peripheral arterial disease and with low ASCVD risk, when is it safe to discontinue low‑dose aspirin (81 mg daily)?

When to Discontinue Aspirin in Hypertensive Patients Without Established ASCVD

In a hypertensive adult with low ASCVD risk and no history of myocardial infarction, stroke, or peripheral arterial disease, aspirin should be discontinued immediately—contemporary evidence demonstrates that bleeding risk equals or exceeds any cardiovascular benefit in this population. 1

Risk Assessment Framework

Before discontinuing aspirin, calculate the patient's 10-year ASCVD risk using validated tools such as the ACC/AHA Pooled Cohort Equations:

• 10-year ASCVD risk < 10%: Aspirin provides no net benefit and should be discontinued. The USPSTF gives a Grade D recommendation (harm outweighs benefit) against aspirin use in this population. 2

• 10-year ASCVD risk 10–15%: Even at this intermediate risk level, the number of bleeding events induced approximately equals the number of cardiovascular events prevented (NNT to prevent ASCVD event = 265; NNT to cause major bleed = 210). 1

• Age > 60 years: The USPSTF concludes with moderate certainty that initiating or continuing aspirin for primary prevention in adults 60 years or older has no net benefit (Grade D recommendation). 3

• Age > 70 years: Aspirin should not be used for primary prevention regardless of ASCVD risk. The ASPREE trial demonstrated increased bleeding and mortality without cardiovascular benefit, with extended follow-up showing higher major adverse cardiovascular events (HR 1.17) and persistent bleeding risk (HR 1.24). 1

Evidence Supporting Discontinuation

The paradigm shift away from aspirin for primary prevention is driven by three landmark 2018 trials (ASCEND, ARRIVE, ASPREE) enrolling over 46,000 participants:

• ASCEND trial: Showed only a 12% reduction in cardiovascular events but a 29% increase in major bleeding (4.1% vs 3.2%). 1

• Meta-regression analysis: Demonstrated that aspirin's treatment effect does not increase as ASCVD risk increases, contradicting the hypothesis that higher-risk patients benefit more. 4

• Contemporary populations: Modern patients have lower smoking rates, widespread statin use (34–75% in recent trials), and improved blood pressure control—factors that lower baseline cardiovascular risk while bleeding risk remains unchanged. 1

Absolute Contraindications Requiring Immediate Discontinuation

Aspirin must be stopped immediately if any of the following are present:

• Prior gastrointestinal bleeding or active peptic ulcer disease 1
• Known bleeding disorder or thrombocytopenia 1
• Concurrent anticoagulation (warfarin or DOACs) 1
• Regular NSAID use 1
• Uncontrolled hypertension 1
• Chronic kidney disease (increases bleeding risk) 1
• Age > 70 years 1

Special Consideration: Hypertension with Diabetes

Even in hypertensive patients with diabetes, aspirin is not routinely recommended for primary prevention:

• The American Diabetes Association states that aspirin is "generally not recommended" even in diabetic patients with elevated ASCVD risk. 1

• The ASCEND trial specifically enrolled 15,480 diabetic participants without prior ASCVD and found that the 12% relative reduction in serious vascular events was offset by a 29% relative increase in major bleeding. 1

• Aspirin may be considered only in diabetic patients ≥50 years with at least one additional major cardiovascular risk factor (family history of premature ASCVD, hypertension, dyslipidemia, smoking, or chronic kidney disease/albuminuria) and low bleeding risk, but only after shared decision-making. 5

When Aspirin Should NOT Be Discontinued

Secondary prevention remains a strong indication: If the patient develops documented ASCVD (myocardial infarction, stroke, coronary revascularization, or peripheral arterial disease), aspirin 75–162 mg daily becomes strongly recommended, as benefits substantially outweigh bleeding risk in this setting. 1

Practical Implementation

1. Calculate 10-year ASCVD risk using the ACC/AHA Pooled Cohort Equations or UKPDS Risk Engine (for diabetic patients). 5

2. Assess bleeding risk factors: History of GI bleeding, age > 60 years, concurrent medications (NSAIDs, anticoagulants), chronic kidney disease, uncontrolled hypertension. 1

3. If ASCVD risk < 10% or age > 60 years without established ASCVD: Discontinue aspirin immediately. 3

4. Optimize evidence-based therapies: Ensure the patient receives statin therapy (if ASCVD risk ≥7.5%), blood pressure control to <130/80 mmHg, smoking cessation, and lifestyle modifications—these interventions have stronger evidence for cardiovascular risk reduction than aspirin. 2

Common Pitfalls to Avoid

• Do not use the 10% 10-year ASCVD risk threshold as an automatic indication for continuing aspirin—contemporary trials show an unfavorable risk-benefit ratio at this cutoff. 1

• Do not overlook bleeding risk factors when calculating net benefit; real-world gastrointestinal bleeding risk may be as high as 5 per 1,000 person-years. 1

• Do not continue aspirin in patients over 70 years without documented ASCVD, as the ASPREE trial demonstrated net harm in this population. 1

• Recognize that aspirin's primary benefit is reduction of non-fatal myocardial infarction, not mortality reduction—the relative risk for cardiovascular mortality is approximately 0.95. 2