Objectives and measures of the ASPREE study
- The primary objective is to determine whether low-dose aspirin prolongs life, or life free of dementia, or life free of significant, persistent physical disability in the healthy elderly.
- Secondary objectives relate to the effects of low-dose aspirin on the key outcome areas of death, cardiovascular disease, dementia and cognitive decline, depression cancer, physical disability and major bleeding episodes.
- Measures in addition to those included in the primary and secondary objectives will be examined. These include measures such as haemoglobin levels, urine albumin:creatinine ratios, cognitive and physical function and hospitalisations.
ASPREE protocol summary
- ASPREE is a double-blind, randomised, placebo-controlled primary prevention trial designed to assess whether daily active treatment of 100 mg enteric-coated aspirin will extend the duration of disability-free life in healthy participants aged 70 years and above.
- The study will examine whether the potential benefits of low dose aspirin (particularly the prevention of heart disease, stroke, certain cancers and dementia) outweigh the risks (particularly severe gastrointestinal bleeding and haemorrhagic stroke) in this age group.
- Participants were eligible for the trial if they did not have a current clinical indication for (i.e. overt cardiovascular disease) or contraindication (i.e. allergy or increased risk of bleeding) to aspirin, did not have dementia, significant physical disability, low haemoglobin levels, or have a condition that was likely to be fatal during the 5 years of the trial, and were capable of attending their usual General Practitioner’s (GP’s) clinic and providing informed consent.
- 19,000 participants will provide 90% power of a true relative risk benefit of 0.90 for the primary endpoint (a composite of all-cause mortality, incident dementia and persistent physical disability) in an intention-to-treat analysis with an average follow-up of 5 years.
- The trial has received financial support from the National Institute on Aging (NIA; part of the National Institutes of Health), the National Health and Medical Research Council of Australia, the National Heart Foundation of Australia and the Victorian Cancer Agency. Bayer Schering Pharma provides in-kind support through the provision of low dose aspirin and matching placebo.
- The study is carried out in community settings in the USA and Australia. In the USA, 2,411 participants were recruited through clinical trials networks in regional hubs. In Australia, recruitment of 16,703 participants was primarily conducted through general practice with the participant’s usual treating GP as co-investigator.
- At present, there is no study that has adequately examined the balance of risks and benefits of aspirin therapy in the elderly. There is a strong possibility that such therapy may not only reduce the risk of myocardial infarction and stroke but may also slow the onset of dementia, improve quality of life and therefore reduce the costs of dependency amongst elderly individuals. On the other hand, there is a possibility that the benefits may be largely offset by increased risks of serious bleeding and a progressive decline in haemoglobin levels. The balance of risks and benefits can be established only by a randomised clinical trial in sufficient participants to accurately weigh these possibilities.