JAMA Oncol

Aspirin in older adults linked to higher cancer mortality in long-term ASPREE follow‑up

February 6, 2026

In this binational (Australian and U.S.) cohort study extending follow-up of the ASPREE randomized trial, 19,114 adults aged ≥70 years (≥65 for U.S. minority participants) had 3,448 incident cancers and 1,173 cancer-related deaths over a median 8.6 years. Low-dose aspirin (LDA) wasn't associated with overall cancer incidence (hazard ratio [HR], 0.98; 95% confidence interval [CI], 0.92–1.05), including by stage or type such as colorectal cancer. However, LDA was associated with higher cancer-related mortality (HR, 1.15; 95% CI, 1.03–1.29). In the post‑RCT observation period, among 14,907 participants without prior cancer, original aspirin assignment wasn't associated with differences in cancer incidence or mortality, indicating no legacy effect.

Clinical takeaway: For adults ≥70 years without existing cardiovascular disease, clinicians should be cautious about initiating daily aspirin for primary prevention, as potential cancer‑related harms may outweigh benefits in this age group.

Source:

Orchard SG, et al. (2026, January 29). JAMA Oncol. Cancer Incidence and Mortality With Aspirin in Older Adults: Follow-Up of the ASPREE Trial. https://pubmed.ncbi.nlm.nih.gov/41609798/