Community-based cohort study of association of low-dose aspirin with cancer incidence and mortality in older adults: follow-up of ASPREE

Prior studies, largely among middle-aged adults, reported that aspirin use reduces cancer risk after 10 years, particularly for colorectal cancer. In contrast, the ASPREE randomized clinical trial of older adults in Australia and the US found that low-dose aspirin (LDA; 100 mg daily) treatment for median of 4.7 years had no effect on overall cancer incidence but increased risk of incident late-stage cancer and cancer-related mortality. Ten-year follow-up of ASPREE (ASPREE-XT) has now been published. In this study of 19,114 adults aged 70 years or older (≥ 65 years for Black and Latino individuals) free of cardiovascular disease, dementia, and independence-limiting physical disability, through extended follow-up (median 8.6 years), no association between LDA exposure and overall cancer incidence was observed. An elevated cancer-related mortality risk that had been seen in the clinical trial phase with LDA was not observed after the trial. The authors conclude that results of this study suggest that initiating a multiyear LDA strategy for prevention of cancer is not recommended in older adults.