A systematic review of COVID-19 studies has revealed an association between the virus and hearing loss.
A total of 56 COVID-19 studies have identified an association between the virus and auditory and vestibular problems. According to the new review, undertaken by The University of Manchester and NIHR Manchester Biomedical Research Centre (BRC) scientists, which pooled data from 24 of these studies, the prevalence of hearing loss is 7.6%, tinnitus is 14.8%, and vertigo is 7.2%.
Findings from the review, which was funded by NIHR Manchester Biomedical Research Centre (BRC), have been published in the International Journal of Audiology.
The data used in the review was primarily self-reported questionnaires or medical records relating to COVID-19 symptoms, rather than the more scientifically reliable hearing tests, however, the scientists have described the quality of the studies as “fair.”
Kevin Munro, Professor of Audiology at The University of Manchester and Manchester BRC Hearing Health Lead said: “There is an urgent need for a carefully conducted clinical and diagnostic study to understand the long-term effects of COVID-19 on the auditory system.
“It is also well-known that viruses such as measles, mumps and meningitis can cause hearing loss; little is understood about the auditory effects of the SARS-CoV-2 virus. Though this review provides further evidence for an association, the studies we looked at were of varying quality so more work needs to be done.”
Further exploring the impact of COVID-19
A recent study led by Professor Munro, suggested that more than 13% of patients who were discharged from a hospital reported a change in their hearing. Munro is now leading a year-long UK study to investigate the possible long-term impact of COVID-19 on hearing among people who have been previously treated in hospital for the virus in which he hopes to accurately estimate the number and severity of COVID-19 related hearing disorders in the UK, and discover what parts of the auditory system might be affected.
They will also explore the association between these and other factors such as lifestyle, the presence of one or more additional conditions and critical care interventions.
PHD researcher, Ibrahim Almufarrij, said: “Though the evidence is of varying quality, more and more studies are being carried out so the evidence base is growing. What we really need are studies that compare COVID-19 cases with controls, such as patients admitted to hospital with other health conditions.
“Though caution needs to be taken, we hope this study will add to the weight of scientific evidence that there is a strong association between COVID-19 and hearing problems.”
Munro added: “Over the last few months I have received numerous emails from people who reported a change in their hearing, or tinnitus, after having COVID-19. While this is alarming, caution is required as it is unclear if changes to hearing are directly attributed to COVID-19 or to other factors, such as treatments to deliver urgent care.”