Is COVID 19 Vaccination linked to Risk of Hearing Loss, explore JAMA studies

Dr Yoav Yanir and his team conducted a retrospective, population-based cohort study to assess the association between the BNT162b2 mRNA COVID-19 (Pfizer-BioNTech) vaccine and SSNHL.

The major outcome assessed was the outcome was SSNHL based on International Classification of Diseases, Ninth Revision (ICD-9) codes in conjunction with concurrent prednisone dispensing. Observed cases of SSNHL, occurring within 21 days after each of the first and second vaccine doses, were compared with the expected cases based on the experience of the population in 2018 and 2019. They then estimated the standardized incidence ratios (SIRs) and attributable risks.

• Upon analysis, the researchers found that the incidence rate of sudden sensorineural hearing loss was 60.77 per 100 000 person-years after the first dose and 56.24 per 100 000 person-years after the second dose.
• They noted that the estimated SIRs were more pronounced in female patients aged 16 to 44 years (SIR, 1.92; 95% CI, 0.98-3.43) and female patients 65 years or older (SIR, 1.68) after 1st vaccine dose.
• They observed the highest estimated SIR in male patients 16 to 44 years (SIR, 2.45) after the second dose.
• They noted that the attributable risks were generally small, and the results were similar when 2019 was used as a reference to estimate the expected number of SSNHL cases.

The authors concluded, “ This study suggests that the BNT162b2 mRNA COVID-19 vaccine might be associated with increased risk of SSNHL; however, the effect size is very small. Further studies are warranted to establish this possible association.”

In an accompanying editorial, Dr Angela K. Ulrich and her team wrote, “Neither study identified clear demographic or clinical risk factors associated with sudden sensorineural hearing loss, nor did they address important measurements regarding the severity and duration of hearing loss or the clinical outcomes after treatment”.

They further added, “The many benefits of COVID-19 vaccines substantially outweigh the rare risks associated with vaccination. Targeted identification of sudden sensorineural hearing loss will aid in future investigations of this condition as an outcome of interest as well as assessments of potential adverse events after immunization and will aid in the timely recognition of sudden sensorineural hearing loss. Ongoing surveillance to detect rare adverse events after vaccination is important to ensuring the safety of these vaccines and engendering the public’s trust.”

For further information:

Study 1: Eric J. Formeister MD, MS,et al. Assessment of Sudden Sensorineural Hearing Loss After COVID-19 Vaccination, JAMA Otolaryngol Head Neck Surg. doi:10.1001/jamaoto.2021.4414.Study 2: Yoav Yanir MD, et al. Association Between the BNT162b2 Messenger RNA COVID-19 Vaccine and the Risk of Sudden Sensorineural Hearing Loss, JAMA Otolaryngol Head Neck Surg. doi:10.1001/jamaoto.2021.4278.