Ubiquitous aspirin: A systematic review of its impact on sensorineural hearing loss

Objective. This systematic review evaluates the impact of aspirin on audiometric outcomes with respect to: (1) doses exceeding 325 mg daily, (2) doses of 325 mg daily or less, (3) studies applicable to the general populace, and (4) studies applicable to those with inflammatory conditions. It also assesses the impact of aspirin on (a) self-reported hearing loss, (b) noise-induced audiometric changes, and (c) the adverse otological effects of aminoglycoside therapy. Data Sources. Computerized searches of MEDLINE, PubMed, Cochrane, and EMBASE databases were performed, updated through January 2014, and supplemented by manual searches and inquiries to topic experts. Review Methods. A systematic review was performed according to an a priori protocol. Data extraction was performed by 2 independent parties and focused on relevant audiological measurements, potential confounders, and study design elements associated with risk of bias, including utilization of randomization, prospective/retrospective data collection, and incorporation of blinding. Results. The 37 criterion-meeting studies included a combined total of 185,155 participants. Aspirin ingestion =1.95 g/d was associated with worse audiometric results (4-112 dB threshold shift); the effect was dose dependent and reversible in the short term. There were no audiometric data that confirm that long-term doses of 81 mg or 325 mg daily have no hearing consequences. Paradoxically, aspirin (in doses shown to be detrimental in isolation) had a protective effect when co-administered with intravenous gentamicin. Conclusions. With the large-scale population utilization of aspirin for cardiovascular prophylaxis, the potential risks to hearing health should be considered for future longitudinal study, particularly given that short-term effects may be reversible.