Follow-up of patients with mild COVID-19 using subjective, acoustic, and aerodynamic measurements

To gain a comprehensive understanding of the vocal repercussions experienced by mild COVID-19 infection, as well as the duration and underlying factors contributing to these effects.

Ten participants with mild COVID-19 infection were included as the experimental group to evaluate the voice metrics changes at 15 days (D15), 30 days (D30), and 60 days (D60) after mild COVID-19 infection, and 10 healthy people were taken as the normal control group. Self-assessment and objective measures were taken at each time point, including questionnaires for voice handicap index (VHI) and reflux symptom index (RSI), as well as acoustic and aerodynamic indicators such as fundamental frequency (F0), Jitter, Shimmer, noise-to-harmonics ratio, sound pressure level (SPL), phonation threshold pressure (PTP), phonation threshold flow, aerodynamic resistance(AR), aerodynamic efficiency, mean expiration airflow, maximum phonation time, and maximum loudest phonation time.

Notable elevations in RSI and VHI were observed during the D15 assessment, but by D60, these levels had returned to normal. At D60, Shimmer, PTP, and PTF significantly increased compared to the control group, while HNR and AR significantly decreased (p < 0.05). F0, SPL, and PTP significantly increased compared to 15 days (p < 0.05), while other acoustic and aerodynamic indicators showed no significant changes in intra-group and inter-group comparisons.

Our study demonstrated that COVID-19 infection has a detrimental effect on voice production. Although subjective discomfort may gradually subside within 2 months after onset, alterations in phonation mode can be delayed. It is essential for healthcare professionals to remain vigilant in preventing any organic changes that may arise due to COVID-19-related voice disorders, such as muscle tension dysphonia.