In healthy elderly, low-dose aspirin increases all-cause and cancer-specific mortality (ASPREE)

Reference

McNeil JJ, Nelson MR, Woods RL, et al, for the ASPREE Investigator Group. Effect of aspirin on all-cause mortality in the healthy elderly. N Engl J Med 2018;379(16):1519-1528.

Synopsis

This is 1 of 3 reports of the same study in the same issue of the New England Journal of Medicine; this one focuses on all-cause mortality. The Aspirin in Reducing Events in the Elderly (ASPREE) trial randomized 19,114 community-dwelling adults to receive either 100 mg of enteric-coated aspirin or placebo. The study was conducted in the United States and Australia, with patients recruited between 2010 and 2014. Participants were 70 years or older (65 years or older if black or Hispanic in the United States, because of their shorter average lifespan), had no serious comorbidity that would be expected to limit their life expectancy to less than 5 years, and no known cardiovascular (CV) or cerebrovascular disease, dementia, high bleeding risk, or contraindication to aspirin. The study included a 1-month placebo run-in period to ensure at least 80% adherence to the study medication. During the run-in period, 4049 patients were excluded, 61% because they failed adherence. Included patients were contacted every 3 months to further encourage adherence and to gather interim data. Outcomes were adjudicated by a committee masked to treatment assignment. The median age of participants was 74 years, 56% were women, and 8.7% were non-white. Most of the patients were recruited in Australia (87%), 74% had hypertension, 65% had hyperlipidemia, and only 11% had diabetes. Participants were followed up for a median of 4.8 years, and only 2.2% withdrew or were lost to follow-up. All-cause mortality was higher in the aspirin group (5.9% vs 5.2%; hazard ratio [HR] 1.14, 95% CI 1.01 - 1.29; number needed to treat to harm [NNTH] = 143 over 4.8 years). The likelihood of cancer death was also higher in the aspirin group, with the increased risk beginning after approximately 3 years of aspirin use (3.1% vs 2.3%; HR 1.31, 1.10 - 1.56; NNTH = 125 over 4.8 years).