Journal Article

Short- and long-term impact of aspirin cessation in older adults: a target trial emulation

Webb, Katherine L., Zhou, Zhen, Woods, Robyn L., Ernst, Michael E., Kirpach, Brenda, Reid, Christopher M., Orchard, Suzanne G., Tonkin, Andrew, Shah, Raj C., Nelson, Mark R., Murray, Anne M., Stocks, Nigel, Wolfe, Rory, Broder, Jonathan C., Chan, Andrew T.

2024

Overview

Background The net benefit of aspirin cessation in older adults remains uncertain. This study aimed to use observational data to emulate a randomized trial of aspirin cessation versus continuation in older adults without cardiovascular disease (CVD). Methods Post hoc analysis using a target trial emulation framework applied to the immediate post-trial period (2017–2021) of a study of low-dose aspirin initiation in adults aged ≥ 70 years (ASPREE; NCT01038583). Participants from Australia and the USA were included if they were free of CVD at the start of the post-trial intervention period (time zero, T0 ) and had been taking open-label or randomized aspirin immediately before T0 . The two groups in the target trial were as follows: aspirin cessation (participants who were taking randomized aspirin immediately before T0 ; assumed to have stopped at T0 as instructed) versus aspirin continuation (participants on open-label aspirin at T0 regardless of their randomized treatment; assumed to have continued at T0 ). The outcomes after T0 were incident CVD, major adverse cardiovascular events (MACE), all-cause mortality, and major bleeding during 3, 6, and 12 months (short-term) and 48 months (long-term) follow-up. Hazard ratios (HRs) comparing aspirin cessation to continuation were estimated from propensity-score (PS) adjusted Cox proportional-hazards regression models. Results We included 6103 CVD-free participants (cessation: 5427, continuation: 676). Over both short- and long-term follow-up, aspirin cessation versus continuation was not associated with elevated risk of CVD, MACE, and all-cause mortality (HRs, at 3 and 48 months respectively, were 1.23 and 0.73 for CVD, 1.11 and 0.84 for MACE, and 0.23 and 0.79 for all-cause mortality, p  > 0.05), but cessation had a reduced risk of incident major bleeding events (HRs at 3 and 48 months, 0.16 and 0.63, p  < 0.05). Similar findings were seen for all outcomes at 6 and 12 months, except for a lowered risk of all-cause mortality in the cessation group at 12 months. Conclusions Our findings suggest that deprescribing prophylactic aspirin might be safe in healthy older adults with no known CVD.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Adults / Aged / Aged, 80 and over / Aspirin / Aspirin - administration & dosage / Aspirin - therapeutic use / Australia / Biomedicine / Bleeding / Cardiovascular disease / Cardiovascular diseases / Cardiovascular Diseases - prevention & control / Cessation / Clinical significance / Disease prevention / Dosage and administration / Elderly / Female / Heart / Heart diseases / Hemorrhage / Hemorrhage - chemically induced / Hospitalization / Humans / Ischemia / Labels / Male / Medicine / Medicine & Public Health / Mortality / Older people / Patient outcomes / Platelet Aggregation Inhibitors - administration & dosage / Randomized Controlled Trials as Topic / Regression analysis / Regression models / Research Article / Risk management / Statistical analysis / Stroke / Target trial / United States