New York,  After loss of taste, respiratory distress, researchers have found evidence that Covid-19 also leads to hearing and balance disorders, as well as aggravating tinnitus symptoms.

The factors that may play a role in the relationship between Covid-19 and hearing are multifold. Covid-19 is known to have inflammatory effects, including in neurological tissue, which can exacerbate other problems, said Colleen Le Prell, from the University of Texas at Dallas.

"Inflammation can damage the auditory and vestibular pathways in the peripheral and central nervous system, just as it damages smell and taste pathways, and other neural systems," Le Prell said.

In addition, there are several studies suggesting the mental anxiety caused by the pandemic, such as lockdown-related stress and concerns about the negative impacts of masks on audibility and communication accessibility, may magnify the auditory impacts of the virus. This is especially so for people who already had tinnitus, prior to the pandemic.

"Increases in tinnitus bothersomeness were associated with reports of pandemic-related loneliness, sleep troubles, anxiety, depression, irritability, and financial worries," Le Prell said. "In other words, participants who experienced general increases in stress reported their tinnitus to be more bothersome than before the pandemic."

Some early experimental treatments, like chloroquine and hydroxychloroquine (which are not recommended by the National Institutes of Health), can also have auditory side effects, particularly in patients with kidney problems.

"When the kidneys are not functioning properly, the drug may not (be) metabolised and eliminated from the body as quickly, which can increase physiological drug concentrations and risk of side effects," Le Prell said.

"Old age is often accompanied by decreased renal function, and Covid-19 can cause renal dysfunction, which increases the risk that a patient who is given an experimental therapy for Covid-19 will be at risk for ototoxicity," Le Prell noted.

Prell presented the study during the 180th Meeting of the Acoustical Society of America, which will be held virtually June 8-10.