January/February 2023
Testing aspirin’s purported fracture-prevention effect

In a randomised trial, daily low-dose aspirin was not associated with lower fractures risk in older people.

Aspirin was associated with lower risk for fracture in a recent meta­ analysis of observational studies (BMJ Open 2020; 10: e026876); a potential mechanism could be aspirin’s effect on prostaglandins, which in turn affect bone remodelling. In this substudy of the ASPREE randomised trial (N Engl J Med 2018; 379: 1499­-1508, 1509­-1518 and 1519­-1528), researchers determined associations between daily low­-dose (100 mg) aspirin and risks for serious falls (i.e. falls that prompt a visit to the hospital) and fractures in 17,000 healthy older adults (median age, 74 years) in Australia who were randomised to receive aspirin or placebo.

After a median 4.6­-year follow up, 1700 serious falls and 2900 fractures had occurred. Risk for serious falls was significantly higher (17%) in the aspirin group than the placebo group. Risk for first fracture did not differ between the groups. Numerous subgroup analyses yielded similar results.

Comment: In this randomised trial, aspirin did not lower risk for fractures, contrary to findings in observational studies. Why it was associated with excess fall risk is unclear: the authors speculate that the aspirin group might have had more post­fall bleeding and bruising than the placebo group, resulting in more hospital visits and higher probability of being diagnosed with a fall.

Regional Vice President – Southwest Wisconsin, Mayo Clinic Health System, La Crosse; Professor of Medicine and Biomedical Ethics, Mayo Clinic College of Medicine and Science, Rochester, USA.

Barker AL, et al. Daily low-dose aspirin and risk of serious falls and fractures in healthy older people: a substudy of the ASPREE randomized clinic trial. JAMA Intern Med 2022; 182: 1289-1297.

This summary is taken from the following Journal Watch title: General Medicine

JAMA Intern Med