Should people over 70 take aspirin for heart disease?

For people over 70 who already have heart disease, aspirin reduces the risk of a second heart attack or stroke, but the bleeding risk is real and increases with age.

The evidence for aspirin in secondary prevention—after a heart attack or stroke—is solid. A large meta-analysis of individual patient data from 17,000 people in secondary-prevention trials found aspirin cut the rate of serious vascular events from about 8.2% to 6.7% per year, a significant reduction [2]. Pooled data from six earlier trials also showed about a 20% drop in total or coronary mortality and nonfatal reinfarction [1]. These trials mostly used aspirin doses of 75–325 mg daily [2][1].

The bleeding risk is the other side of the scale. In the same meta-analysis, aspirin roughly doubled the rate of major gastrointestinal bleeding in primary-prevention populations [2]. The risk climbs steeply with age: people over 75 have about a 9-fold higher risk of NSAID-related GI complications compared to younger adults [4]. A 2020 review of the ASPREE trial, which studied 19,114 healthy people over 70, found aspirin did not reduce cardiovascular events and actually increased all-cause mortality (HR 1.14) and major bleeding (HR 1.38) [3]. That trial was in primary prevention, but it shows the bleeding risk in this age group is not trivial.

The trade-off is different for someone who has already had a heart attack or stroke. Their baseline risk of a repeat event is high enough that the benefit of aspirin may outweigh the bleeding risk, especially if they have no history of ulcers or bleeding. But the decision should be individual, not automatic. The evidence does not support a blanket "everyone over 70 with heart disease should take aspirin." It supports weighing the person's specific risk of a repeat event against their specific bleeding risk.

The retrieved studies do not include a large, modern trial that directly compares aspirin to no aspirin specifically in people over 70 with established heart disease, measuring both cardiovascular events and bleeding. That is the study that would settle the question. Until it exists, the best evidence comes from trials that included older adults and from the known age-related increase in bleeding risk.

My call: for a person over 70 with established heart disease and no history of bleeding, aspirin likely reduces the risk of a second heart attack or stroke, but the benefit is modest and the bleeding risk is real. The decision should be made with a clinician who will weigh both sides honestly, not one who prescribes it by rote. Confidence: moderate.