Ubiquitous Aspirin: A Systematic Review of Its Impact on Sensorineural Hearing Loss

Abstract

Objectives: The primary goal of this systematic review was to test the null hypotheses: (1) aspirin has no impact on the prevalence of sensorineural hearing loss; and (2) any such impact is not dose-dependent. Methods: Computerized searches of MEDLINE, PubMed, Cochrane, and EMBASE databases through January 2014 were performed with manual searches and inquiries to topic experts. A systematic review was performed according to an a priori standardized protocol. Data extraction was performed by 2 independent parties (an audiologist and an otolaryngologist) and focused on relevant audiological measurements, study designs, and potential confounders. Results: The 37 criterion-meeting studies included a combined total of 185,155 participants. Audiometric data consistently suggested aspirin had a deleterious, dose-dependent effect. The strongest data analysis arose from a randomized placebo-controlled trial, which demonstrated worse pure tone thresholds, speech discrimination scores, and hearing in background noise in the group receiving aspirin in 325 mg doses. Data from self-report of hearing symptoms suggests the potential for effect modification by sex. Paradoxically, level 1 evidence also demonstrates that aspirin has a protective effect on hearing when co-administered with gentamicin. Conclusions: With the large-scale population use of aspirin for cardiovascular prophylaxis and other benefits, the potential risks to hearing health should be considered, particularly given that the effects may be reversible or improved with altered dosing. With the increasing prevalence of hearing loss in all age groups and segments of the population, attention to widespread exposures of risk may help preserve hearing-related health.