Low-dose aspirin does not affect the progression of age-related hearing loss

By Vijay Kumar MalesuReviewed by Lily Ramsey, LLMJul 30 2024

In a recent study published in the JAMA Network Open, a group of researchers compared the effect of daily low-dose aspirin versus placebo on the progression of age-related hearing loss in healthy older adults.

Study: Low-Dose Aspirin and Progression of Age-Related Hearing Loss. Image Credit: Olesia Bech/Shutterstock.com

Background 

Age-related hearing loss affects over half of adults aged 70 years or older, leading to depression, social isolation, and reduced quality of life. It is marked by impaired speech discrimination and high-frequency loss.

Smoking and diabetes are established risk factors. The pathophysiology involves cochlear degeneration (Inner ear deterioration), including stria vascularis atrophy (cochlear tissue wasting) and hair cell loss.

Microvascular changes may contribute to this degeneration. Aspirin, known for preventing platelet aggregation and reducing inflammation, might enhance cochlear blood flow and reduce cellular damage. However, human data are inconsistent.

Further research is needed to explore the potential long-term benefits and the effectiveness of alternative anti-inflammatory agents in slowing the progression of age-related hearing loss.

About the study 

The present double-blinded, randomized, placebo-controlled trial involved 19,114 participants recruited between January 2010 and December 2014.

Participants, free from cardiovascular disease, dementia (severe cognitive decline), significant disability, or life-limiting illness, were followed up annually and by phone every six months.

After a 4-week placebo run-in to assess adherence, participants were randomized to receive either placebo or 100 mg daily of enteric-coated aspirin.

Hearing assessments, excluding those with bilateral cochlear implants or deeply inserted hearing aids, were conducted in community centers, clinics, or mobile vans using portable audiometers. Measurements included air conduction thresholds and speech perception in noise at baseline, 18 months, and 3 years.

The study's main outcomes were hearing measures, including mean sound detection thresholds for individual pure tones, 4 frequency average (4FA), and speech reception threshold (SRT).

Only 22% of participants completed the year 3 assessment, which was prematurely stopped in June 2017. Using a linear mixed model, statistical analysis from June to December 2023 showed no significant differences in hearing outcomes between the aspirin and placebo groups. 

Study results 

After excluding participants with unmanaged bilateral occlusion at baseline, those who died before the 18-month follow-up, and individuals who did not complete their third hearing visit within the trial period, the final analysis included 279 participants: 141 to placebo and 138 assigned to aspirin.

Baseline characteristics were well-matched between the groups. The median age was 73.1 years, with a gender distribution of 55% men and 45% women. Approximately 70% of participants in each group had some hearing loss at baseline.

In the aspirin group, 17% reported using hearing aids, and 17% reported loud noise exposure in the previous five years. In the placebo group, 19% reported using hearing aids, and 8% reported loud noise exposure.

Both groups had similar proportions of never-smokers and alcohol consumers. Most participants were non-frail and free from diabetes at baseline, with 70% in the aspirin group and 72% in the placebo group reporting hypertension.

Medication adherence was approximately 70% for both groups. Baseline characteristics of included participants were similar to those of excluded participants, except for a higher proportion of women among the excluded group.

Over three years, the mean 4FA sound detection thresholds increased in both groups, but there was no significant difference in the progression of hearing acuity between the groups for any tested pure tones.

Likewise, no significant differences were found in mean SRT between the aspirin and placebo groups at any time point. Self-reported hearing handicap at baseline was 31% in the placebo group and 34% in the aspirin group, with a modest increase by year 3, remaining similar between groups.

Stratified analyses by sex, age, diabetes, and smoking status showed no modification effect by treatment on hearing measures from baseline to year 3.

Changes in mean hearing thresholds between baseline and year 3 were similar between the aspirin and placebo groups, with no statistically significant differences in SRT.

Sensitivity analysis included participants who completed their year 3 hearing assessment within 3 or 6 months after the trial. Results showed no differences between treatment groups for changes in hearing thresholds at 4 kHz, 4FA, or SRT from baseline to either 3 or 6 months after the trial assessment. 

Conclusions 

To summarize, this study demonstrated that a daily intervention of 100 mg aspirin over three years had no discernible effect on the progression of hearing loss among healthy participants aged 70 years or older.

Results remained consistent when stratified by age, sex, smoking status, and diabetes. Low-dose aspirin did not affect SRT or perceived functional hearing limitations (HHIE-S).

Despite evidence suggesting aspirin's potential to address microvascular and inflammatory components of age-related hearing loss, the trial showed no beneficial impact on hearing acuity or functional hearing abilities, nor did it indicate any deleterious effects associated with aspirin use.