Aspirin without known heart disease

Known cardiovascular disease? No

Recommendationaspirin-primaryFewer than 5 people have reached this rule so far

Aspirin is not routine for prevention — ask before starting or stopping

Clinical review

No clinician has signed off this rule yet. It reflects our reading of the guidelines cited below, which has not been independently checked.

What someone who reaches this rule is told

Word for word, as generated for the example person below. Figures in the text are theirs.

Worth raising with your doctor
If you're taking a daily aspirin "just in case" and you've never had a heart attack or stroke, ask your doctor whether you still should be.
Proven in trialsTrials counted real events, like heart attacks, strokes, or deaths, and this changed them.
ACC/AHAClass 2bLevel A
Why, and the source
Guidance changed here and many people are still on aspirin from an older era. Three large trials (ASPREE, ARRIVE, ASCEND) found that for people who have never had a cardiovascular event, the bleeding it causes roughly cancels the events it prevents. It's no longer routine — it's a case-by-case decision, and it's specifically discouraged over age 70. Don't start or stop it without asking.
Where the guidelines stand
ACC/AHA (US)
RecommendsClass 2bLevel A
Low-dose aspirin might be considered only for select adults aged 40 to 70 at higher risk who are not at increased bleeding risk. The 2019 guideline removed the earlier risk-score threshold.
2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular D… · Recommendation behind this rule · class and level read from the guideline tables on 2026-09-30
Recommends againstClass 3: HarmLevel B-R
Adults over 70 (not routine)
2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular D… · Graded separately within the same recommendation · class and level read from the guideline tables on 2026-09-30
Recommends againstClass 3: HarmLevel C-LD
Adults of any age at increased risk of bleeding
2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular D… · Graded separately within the same recommendation · class and level read from the guideline tables on 2026-09-30
2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease · Class 2b · Level A

An example person who reaches it

“Low risk, nothing flagged” — an illustrative profile, not a real user.

42-year-old womanBP 118/74LDL 10010-yr PREVENT-ASCVD 0.6%

Their path through prevention essentials

Known cardiovascular disease?No ← this rule
Has Lp(a) ever been measured?No

Sources

Cited by the recommendations above.

2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease

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