Aspirin in Reducing Events in the Elderly

Overview

ASPREE-XT is a post-treatment, longitudinal observational follow-up study of ASPREE participants \[ASPREE Investigator Group, 2013; www.aspree.org; McNeil et al 2017\]. Although the ASPREE trial medication was ceased, the study activity was not stopped and ASPREE participants are continuing with scheduled visits and phone calls. An observational follow-up phase (ASPREE-XT), began in January, 2018. This will enable the monitoring of possible delayed effects of aspirin treatment, primarily on cancer incidence, metastases and mortality. In addition to monitoring the incidence of malignancy within the ASPREE cohort, the opportunity will be taken to observe any other residual effects of aspirin on the endpoints being monitored in the cohort. Continuity of contact with study participants is the key to retention of the cohort for any ongoing or future studies.

ASPREE BACKGROUND: ASPREE (ASPirin in Reducing Events in the Elderly) is a joint US/Australian research project aiming to determine whether low-dose aspirin increases healthy life-span, defined as survival free of dementia and disability. ASPREE began in 2010 and completed recruitment in 2014. It is a randomized, double-blind, placebo-controlled, primary prevention trial of daily 100 mg of aspirin in a population of healthy older people in the United States (US) and Australia with a period of treatment averaging 4.5 years. ASPREE's primary outcome is length of survival free of dementia and disability and has secondary outcomes encompassing the major health issues related to aging. The trial involving 19,114 persons aged 70 and above (65 years and above for US minorities) is distinctive for its large size, methodological rigor and high participant retention rate in both countries. ASPREE UNIQUE ASPECTS: 1. It is the first large scale trial to incorporate dementia-free and disability-free survival as a primary outcome. This is now recognized as an appropriate goal of treatment in a primary prevention population of this age group. Within a clinical trial context disability-free survival incorporates an estimate of the overall benefits and risks of aspirin in a single outcome measure. 2. It is one of the first primary prevention trials of aspirin to include cancer incidence, metastases or mortality as a pre-specified endpoint. Recent meta-analyses \[Rothwell et al 2010, 2011, 2012\] suggests that aspirin has a significant chemopreventive effect becoming evident after a period of 4+ years of aspirin treatment, but questions remain about the magnitude of benefit, and whether it applies to treatment of all cancers and to older people. 3. It will provide information about the impact of aspirin on a range of other conditions (e.g, dementia, CVD, stroke, depression, bleeding) where aspirin has been claimed to have benefit (or risks). The intervention phase of the trial ended in June 2017 after the NIA determined that it was highly unlikely that aspirin would show a benefit on the overall primary outcome within the planned 5-year time frame. The study is now entering a data cleaning and analysis phase and it is anticipated that the primary results were published in September 2018.