To balance the benefits and risks, prior US guide- lines have recommended prophylactic aspirin only in the setting of elevated ASCVD risk (eg, as calculated by risk estimators like the PCE or based on the presence of specific ASCVD risk Meta-regression analyses of his- torical trials show that observed ASCVD risk tracks reasonably well with baseline-estimated ASCVD In contrast, observed bleeding risk on aspirin is less well correlated with baseline-esti- mated ASCVD risk.S4.6-19 (A nonexhaustive list of scenarios associated with increased risk of bleed- ing includes: a history of previous gastrointestinal bleeding or peptic ulcer disease or bleeding from other sites, age >70 years, thrombocytopenia, coagulopathy, CKD, and concurrent use of other medications that increase bleeding risk, such as nonsteroidal anti-inflammatory drugs, steroids, direct oral anticoagulants, and warfarin.) In this context, post hoc study of older trials suggests that the benefit risk ratio for prophylactic aspirin generally becomes more favorable at >10% esti- However, the relative benefits of aspirin, specifically in pre- venting nonfatal MI and perhaps stroke (with a trend to lower mortality) have been less evident in more recent trials.S4.6-9,S4.6-16,S4.6-17,S4.6-20 Similarly, in these recent trials, the estimated ASCVD risk has generally exceeded the actual risk observed during These recent data are the rationale for the lower COR for prophylactic aspirin in the present guideline (Class IIb) and the removal of a specific PCE risk threshold as an inclusion criterion for aspirin consideration. 