Characteristics of sudden hearing loss after different COVID-19 vaccinations: a systematic review and meta-analysis

COVID-19 vaccines are essential to prevent complications and reduce the burden of SARS-CoV-2. However, these vaccines showed side effects such as fatigue, pain, fever, and rarely hearing loss. In this review, we aim to summarize studies investigating hearing loss following COVID-19 vaccination and try to find the possible association and risk factors for this hazardous complication.

We performed a comprehensive search of five electronic databases (PubMed, Scopus, Web of Science, google scholar, Cochrane) from inception until 9 October 2022. We finally included 16 studies after the first and second scans. We used SPSS to analyze the extracted data.

A total of 630 patients were identified, with a mean age of 57.3. Of the patients, 328 out of 609 vaccinated patients took the Pfizer-BioNTech BNT162b2 vaccine, while 242 (40%) took the Moderna COVID-19 vaccine. The mean time from vaccination to hearing impairment was 6.2, ranging from a few hours to one month after the last dose. The results found a significant difference between vaccine types in terms of incidence and prognosis of the condition, while they showed that the number of doses prior to the onset had no significance.

SNHL has been reported in a small number of people who have received the COVID-19 vaccine, but it is unclear at this time whether the vaccine is directly causing this condition. However, the COVID-19 vaccine has been demonstrated to be safe and effective in preventing illness, and the benefits of vaccination are significant compared to any potential risks.

The protocol of this study was registered on Prospero CRD42022367180.