Evaluation of Disturbances in Hearing, Tinnitus, and Dizziness as Signs of COVID-19 Infection

Google Trends Analysis of Otologic Symptom Searches Following COVID-19

Introduction

COVID-19 infection was accompanied by otologic symptoms, a pattern that was captured early by Google Trends. The objective of this study is to investigate searches for otologic symptoms and identify correlations with the pandemic onset.

Materials and Methods

Search interest for otologic symptoms was gathered using Google Trends from two years before and two years following the pandemic start date. A two-tailed Mann-Whitney U test was used to identify significant changes and effect size.

Results

In total, search interest for 14 terms was collected, with significant changes identified in 11. Six terms showed increased search interest, with the most significant rises observed for headache (r=0.589, p<0.001), dizziness (r=0.554, p<0.001), and tinnitus (r=0.410, p<0.001). Search interest decreased for five terms, with the most notable declines found in searches for migraine headache (r=0.35, p<0.001) and phonophobia (r=0.22, p=0.002). No significant changes were seen in ear pressure (p=0.142), neck pain (p=0.935), and sudden hearing loss (p=0.863) searches.

Conclusion

COVID-19 infection is often accompanied otologic symptoms and holds a diagnostic role. Fluctuating search interest may be attributed to a true increase in cases, media trends, or people's desires to stay informed. Google Trends robustly captured trends in search interest and presented itself as a valuable epidemiological tool.

Sudden Hearing Loss Waves: The Effect of COVID-19 Infection and Vaccination on the Inner Ear

Sudden sensorineural hearing loss (SSNHL) has emerged as a potential complication of COVID-19 infection and vaccination. Various mechanisms by which the SARS-CoV-2 virus can cause hearing loss have been reported, including direct viral invasion, neuroinflammation, blood flow disturbances, and immune-mediated response. However, the temporal relationship between COVID-19 infection and SSNHL remains unclear, with mixed findings and conflicting results reported in different studies. Similarly, while anecdotal reports have linked COVID-19 vaccination to SSNHL, evidence remains scarce. Establishing a correlation between COVID-19 vaccines and SSNHL implies a complex and multifactorial pathogenesis involving interactions between the immune system and the body's stress response. Nevertheless, it is important to consider the overwhelming evidence of the vaccines' safety and efficacy in limiting the spread of the disease and remains the primordial tool in reducing death.

Number of initial symptoms of SARS-CoV-2 infection is associated with the risk of otological symptoms: a retrospective study

BACKGROUND

The characteristics of otological symptoms in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are lacking. Almost no research has been conducted to explore the emergence of otological symptoms after coronavirus disease 2019 infection. The aims of this study were to investigate the prevalence and specific clinical characteristics of and risk factors for otological symptoms among patients with SARS-CoV-2 infection.

METHODS

We included two groups to investigate the prevalence and clinical characteristics of otological symptoms among patients with SARS-CoV-2 infection. The first sample (S1) was drawn retrospectively from four communities via questionnaires, and the second sample (S2) from an outpatient clinic.

RESULTS

A total of 189 participants were included in S1 (124 women [65.6%]; mean [standard deviation (SD)] age, 33.66 [13.56] years), and 47 in S2 (25 women [53.2%]; mean [SD] age, 45.28 [14.64] years). The most prevalent otological symptoms in S1 were dizziness (15.9%), tinnitus (7.9%), aural fullness (6.9%), otalgia (5.3%), hearing loss (1.6%), and otopyorrhoea (1.1%). Moreover, for each additional typical symptom of SARS-CoV-2 infection, the risk (odds ratio) of otological symptoms increased by 1.33 (95% confidence interval: 1.10-1.61, p = 0.003). The prevalence of aural fullness was higher in the unvaccinated group than that in the group receiving two or three vaccinations (p = 0.018).

CONCLUSIONS

Various otological symptoms may occur in patients with SARS-CoV-2 infection. The number of typical symptoms of SARS-CoV-2 infection is positively associated with the probability of otological symptoms. However, vaccination may reduce the probability of certain otological symptoms.

Association between COVID-19 and sensorineural hearing loss: Evidence from a Mendelian randomization study in European and East Asian population

BACKGROUND

Long coronavirus disease (COVID), characterized by persistent and sometimes debilitating symptoms following a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, has garnered increasing attention as a potential public health crisis. Emerging evidence indicates a higher incidence of hearing loss in individuals who have had COVID 2019 (COVID-19) compared to the general population. However, the conclusions were inconsistent, and the causal relationship between COVID-19 and sensorineural hearing loss remains unknown.

METHODS

To addresses this outstanding issue, we performed Mendelian randomization analysis to detect the causal association between COVID-19 and hearing loss using the largest genome-wide association study data to date in the European population and confirmed the results in the East Asian population. Comprehensively sensitive analyses were followed, including Cochran's Q test, Mendelian randomization (MR)-Egger intercept test, MR-pleiotropy residual sum and outlier, and leave-one-out analysis, to validate the robustness of our results.

RESULTS

Our results suggested that there is no causal association between COVID-19 and the risk of hearing loss in the European population. Neither the susceptibility, hospitalization, and severity of COVID-19 on hearing loss (inverse variance weighted method: odds ratio (OR) = 1.046, 95% confidence interval (CI) = 0.907-1.205, p = .537; OR = 0.995, 95% CI = 0.956-1.036, p = .823; OR = 0.995, 95% CI = 0.967-1.025, p = .76). Replicated analyses in the East Asian population yielded consistent results. No pleiotropy and heterogeneity were found in our results.

CONCLUSION

In conclusion, our MR results do not support a genetically predicted causal relationship between COVID-19 and sensorineural hearing loss. Thus, the associations observed in prior observational studies may have been influenced by confounding factors rather than a direct cause-and-effect relationship. More clinical and mechanism research are needed to further understand this association in the future.