Objective: This systematic review examined current literature, summarised research findings and identified research gaps regarding the efficacy of statins on audiological outcomes.
Methods: Systematic search of electronic databases and grey literature was performed. Eligibility criteria were the study of a statin drug with report of audiological outcomes such as hearing, tinnitus or balance in either human or animal studies. Data extraction and quality assessment were performed by two independently researchers. The characteristics of the study and research findings were collated and summarised. A narrative synthesis was conducted. Meta-analysis was not possible due to heterogeneity of the included studies.
Results: Analysis of searches yielded 17 studies meeting the criteria. Included studies had variable drug type and dosage, outcome measures and associated inner ear conditions. Most animal experiments showed promising audiological outcomes after statin treatment, demonstrated by the results of auditory brainstem response, distortion product otoacoustic emissions and inner ear histology. However, no clear effect can be discerned in human trials due to the mixed results, and heterogeneity in research methodology and quality. Audiological outcomes were not always correlated with cholesterol levels.
Conclusions: Statins remain a potential candidate as otoprotective agents which warrant further investigation.
Keywords: Hydroxymethylglutaryl-CoA reductase inhibitors; audiogram; hearing; otoprotection; statins.
© 2019 John Wiley & Sons Ltd.