Study to determine whether low-dose aspirin in healthy older adults prevents cognitive decline in those identified as having moderate to severe sleep apnoea: the SNORE-ASA substudy of the Aspirin in Reducing Events in the Elderly (ASPREE) study.

INTERVENTION: This study is a sub study of the Aspirin in Reducing Events in the Elderly study (ASPREE, ClinicalTrials.gov identifier NCT01038583, website www.aspree.org). ASPREE is a double blinded, randomised controlled trial of low dose daily aspirin, 100mg oral tablets versus placebo, taken daily for five years in healthy participants aged 70 and over, followed over 5 years for the primary outcomes of dementia‐free survival and disability‐free survival. It is a primary prevention study. The SNORE‐ASA study will involve a subset of newly enrolling participants in the parent ASPREE study. Prior to randomisation into the parent ASPREE study, SNORE‐ASA participants take home a small, light and portable home sleep apnoea screening device named ApneaLink Plus. This device has a nasal cannula to measure airflow, a finger clip pulse oximeter, and can calculate the Apnoea Hypnoea Index (AHI) and Oxygen Desaturation Index (ODI), both of which are measures of the presence and severity of sleep apnoea. Participants are required to wear this for one night only, at study entry only. While participants in the ASPREE study are randomised to oral aspirin 100mg or placebo taken once a day for five years, the SNORE‐study outcome measures will be performed after 3 years. However, unblinding of whether the SNORE‐ASA participants were randomised to either placebo or aspirin will not take place until after the 5 years of the parent ASPREE study. A further subset of participants in the SNORE‐ASA study will undergo a brain MRI and have retinal vascular imaging (also called retinal photography) at baseline and after 3 years to investigate the mechanism by which sleep apnoea may potentiate cognitive decline, and how aspirin may be protective against this. CONDITION: Cognitive decline Sleep Apnoea PRIMARY OUTCOME: Cognitive decline as measured by change in the modified mini mental state examination (3MS) SECONDARY OUTCOME: Change in Retinal Vascular Imaging (RVI) parameters Change in brain MRI measures of white matter hyperintensity including volume Cognitive decline as defined by a fall in summed average z‐scores of >1 SD on any cognitive domain evaluated INCLUSION CRITERIA: Enrolling into the parent ASPREE study. Aged 70 and over Able and willing to provide informed consent