(PP1308) The Effects of COVID-19 on Auditory Function

Abstract:
COVID-19 may have a deleterious effect on the auditory system that manifests as elevated hearing thresholds, an increase in tinnitus severity, and/or a change in auditory gating function following the onset of the virus within a human subject.



 

Summary: Rationale/

Purpose:
Numerous studies have proposed that COVID-19 has a deleterious effect on the human auditory system (Fraczek et al., 2020; Karimi-Galougahi et al., 2020; Kilic et al., 2020; Lang et al., 2020; Munro et al., 2020). Large-scale surveys have indicated that these effects manifest as hearing loss and/or an increase in perception of tinnitus severity (Beukes et al., 2020). Chronic effects of COVID-19 have also been reported to impact both central (CNS) and peripheral nervous systems (PNS) (Wang et al, 2020). It is hypothesized that participants having contracted COVID-19 will demonstrate results reflective of inner ear damage of the peripheral system and reduced function of the central system.

Methods:
Participants in each of two groups (sample size of 50 adults, 25 in the COVID group and 25 in the non-COVID group) will be matched according to age and gender. Peripheral auditory function will include the following measures: pure-tone average (PTA), high-frequency pure-tone average (HF PTA), extended HF PTA, and DPOAEs. Central auditory function will include the following variables: speech perception threshold in background noise, Tinnitus Handicap Inventory (THI) score, and cortical auditory evoked potentials (CAEP) P50, N1, and P2 amplitude ratios. 
Questionnaires will be used to assess severity of tinnitus symptoms (THI), identify causes of hearing loss and tinnitus (NOISE) (Schultz et al., 2020), and determine the effect of COVID-19 on experiences of tinnitus (Beukes et al., 2020).
Participants will complete the standard audiological test battery complemented by DPOAEs and EHF thresholds. An EEG recording session via a 128-channel electrode net (Electrical Geodesic, Inc.) will be used to measure cortical responses to 700 tonal pairs at 50 dB HL with an insterstimulus interval of 500 ms and an interpair interval of 7 seconds (Campbell & Sharma, 2013; Campbell et al., 2018, 2019, 2020a,b). 
Pure-tone averages (500, 1000, and 2000 Hz), HF averages (6000 and 8000 Hz), and EHF averages (10000, 12500, and 16000 Hz) will be calculated. DPOAEs will be recorded from 3000 to 10000 Hz and averaged. Speech perception in background noise assessed via QuickSIN will indicate the SNR threshold in decibels. THI scores will indicate severity of tinnitus perception across 5 categories ranging from slight to catastrophic. EEG analyses will be completed in EEGLAB (Delorme & Makeig, 2004) through MatLab (The MathWorks Inc., 2014). 300 trials of each tone will be completed. A frontal region of interest (ROI) will be created. CAEPs will be determined as follows at the following approximte latencies: P50 at 50ms, N1 at 100ms, and P2 at 200ms. Peak amplitudes in response to the two tonal pairs will be compared by calculating a ratio (Dalecki et al., 2011; Smith et al., 2013).
Peripheral auditory analysis variables and central auditory analysis variables will be compared across groups using separate MANOVAs to ascertain significant amplitude differences between groups. A post-hoc regression will be conducted to determine a relationship between variables and time since viral contraction.

Results and

Conclusions:
Currently in progress.