Taking low-dose aspirin daily does not slow the progression of age-related hearing loss in healthy older adults, according to new Australian-led research.
The researchers had hoped aspirin might help delay hearing loss through its blood circulation and anti-inflammatory effects.
But their trial of 279 Australians aged 70 years or older (median age 73 at baseline) found 100mg aspirin a day was no better than placebo for slowing age-related hearing loss.
However, they said more investigation was warranted on whether a longer follow-up or the use of a more powerful anti-inflammatory agent might prove beneficial.
“Aspirin use did not affect the age-related decline in hearing threshold or in binaural speech perception threshold compared with placebo over a follow-up period of three years,” the researchers wrote in JAMA Network Open on 25 July 2024.
Researchers included Professor Gary Rance from the HEARing Cooperative Research Centre, Melbourne, who holds the Graeme Clark Chair in Audiology and Speech Science at the University of Melbourne, and Dr Harvey Dillon from the HEARing Cooperative Research Centre, Melbourne, the Hearing Research Centre, Macquarie University and the Manchester Centre for Audiology and Deafness, University of Manchester, UK.
The ASPREE-Hearing (Aspirin in Hearing, Retinal Vessels Imaging and Neurocognition in Older Generations) substudy was embedded within the parent ASPREE (Aspirin in Reducing Events in the Elderly) clinical trial.
ASPREE was a double-blinded, randomised placebo-controlled trial that aimed to assess the effect of low-dose aspirin on disability-free survival in 19,114 relatively healthy people aged 70 years or older (or 65 and older for US participants of racial and ethnic minority groups).
Newly recruited Australian ASPREE participants excluding those with bilateral cochlear implants and implanted hearing aids were invited to participate in the ASPREE-Hearing substudy.
Participants were 279 healthy community-dwelling individuals living in Australia aged 70 or older and free of overt cardiovascular diseases, dementia, and life-limiting illnesses. They were recruited between 1 January 2010 and 31 December 31 2014 and followed over three years. Statistical analysis was completed from June to December 2023.
Hearing loss at baseline was reported in 98 of 138 participants (71%) in the aspirin group and 94 of 141 participants (67%) in the placebo group.
Compared with placebo, aspirin did not affect the changes in mean (standard deviation) 4-frequency average hearing threshold from baseline to year three (aspirin: baseline, 27.8 [13.3] dB; year 3, 30.7 [13.7] dB; difference, 3.3 [3.9] dB; placebo: baseline, 27.5 [12.6] dB; year 3, 30.9 [13.8] dB; difference, 3.0 [4.8] dB) nor any other tested frequencies.
An increase in air conduction threshold indicates a deterioration in hearing.
Similarly, for the mean (SD) speech reception threshold, there was no significant difference observed between the aspirin and placebo group at the year three follow-up assessment (aspirin: baseline, –9.9 [3.8] dB; year 3, –9.1 [3.8] dB; difference, 0.9 [2.9] dB; placebo: baseline, –10.5 [7.1] dB; year 3, –9.6 [4.1] dB; difference, 0.9 [5.9] dB; P = .86).
Findings were consistent across sex, age groups, diabetic and smoking status.
The researchers said age-related hearing loss was common in the aging population, affecting communication and contributing to a worsened quality of life.
“It occurs as a result of cochlear degeneration and may be further exacerbated by inflammation and microvascular changes, as observed in animal models,” they wrote.
“This study has demonstrated that an intervention using 100 mg of aspirin daily over a three-year follow-up had no discernible effect on the progression of hearing loss among healthy participants aged 70 years or older.
“The result was unchanged when participants were stratified according to age (over or under 75), sex, among smokers and ex-smokers, and individuals with diabetes.
“Low-dose aspirin also did not affect SRT (speech reception threshold), an indicator of functional hearing ability, or perceived functional limitations associated with hearing impairment (HHIE-S)”.
They said the rationale for studying the effect of aspirin was based on its potential to affect key aspects of the pathology of age-related hearing loss. There was evidence that degenerative changes affecting the microcirculation of the cochlea may be important in the development of age-related hearing loss.
The potential of aspirin, through its ability to prevent platelet aggregation and clumping, to maintain blood circulation through aging capillaries provided a rationale to explore its action in delaying the progress of age-related hearing loss.
Another potentially useful property of aspirin was its anti-inflammatory action. Chronic low-grade inflammation accompanied aging in most animal species and had been implicated in age-related hearing loss, they added.
“The clinical implications of this study result from the widespread regular use of aspirin among older individuals and the observational data linking chronic use of analgesic use with hearing loss,” they said. “Despite the lack of an expected beneficial effect of low-dose aspirin, we did not identify a deleterious effect similar to that seen in the US Health Professionals observational study.”
“Although our findings add valuable data to the ongoing discussion surrounding aspirin and hearing health, future trials will be necessary to determine whether other anti-inflammatory or antiplatelet agents exert a protective effect on hearing loss,” they added. “Furthermore, the complex relationship between aspirin, inflammation, and hearing loss warrants continued investigation to elucidate potential mechanisms and clinical implications.”
Other researchers were Professor John McNeil (supported by an NHMRC Leadership Fellowship) and colleagues from the School of Public Health and Preventive Medicine, Monash University – Mr David Clark, Dr Zhen Zhou, Dr Sultana Hussain, Ms Cammie Tran, Dr Carlene Britt, Dr Elsdon Storey, Dr Judy Lowthian, Dr Rory Wolfe and Dr Robyn Woods; and Dr Raj Shah from Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, US.
The ASPREE trial was funded by America’s National Institute on Aging/National Cancer Institute of the National Institutes of Health, the National Health and Medical Research Council in Australia, the Victorian Cancer Agency and Monash University. ASPREE-Hearing received funding from Monash University and the Deafness Foundation.
