These people are more likely to suffer taste loss after COVID-19

By Stephen Beech via SWNS

Around four in every 10 COVID-19 patients experience some form of taste loss - with middle-aged victims the most likely to be hit, according to the largest study of its kind.

Women with COVID-19 are also more likely to be affected than men, suggests the research.

Reports of loss of taste as a symptom of the virus, have been on the rise over the last two years.

Scientists say that it manifests itself in different forms - including ageusia (total taste loss), hypogeusia (partial loss), and dysgeusia (taste distortion).

While it can be a distressing experience, scientists have been skeptical about whether all reports of the symptom are genuine.

The doubts stemmed from knowledge that loss of taste was rare prior to the pandemic and can often be confused with smell loss, because the two senses are closely linked.

But the new study by researchers from the Monell Chemical Senses Centre in the United States show that reports of taste loss are in fact genuine and distinguishable from smell loss.

Their paper, published in the journal Chemical Senses, examined the prevalence of inability to taste in COVID-19 patients and how the symptom was measured might impact the prevalence estimate. The analysis was the largest undertaken to date.

The research team reviewed data from 241 studies, published between May 2020 and June last year and involving more than 138,000 patients, that assessed taste loss.

Among those patients, 32,918 reported some form of taste deprivation. Eventually, the overall estimate of prevalence was 37 percent.

In other words, “about four in every 10 COVID-19 patients experience some form of taste loss,” said study first author Doctor Mackenzie Hannum.

The team also found that age and sex influenced the prevalence.

Those aged 36 to 50 had the highest prevalence of taste loss out of all age groups.

And female patients are more likely to lose their sense of smell than their male counterparts, said Dr. Hannum.

Studies included in the analysis used different approaches: self-reports or direct reports.

Dr. Hannum, a postdoctoral fellow, said: “Self-reports are more subjective and can be in the form of questionnaires, interviews, health records, for example.

“On the other hand, direct measures of taste are more objective. They are conducted using testing kits that contain various sweet, salty, and sometimes bitter and sour solutions given to participants via drops, strips, or sprays.”

Based on a previous analysis of smell loss by the same Monell research team, direct tests were expected to be a more sensitive measure than self-reports.

This time, however, their findings were different - whether a study used self-reports or direct measures of taste did not impact the estimated prevalence of taste loss.

In other words, objective direct measures and subjective self-reports are as good as each other in detecting the inability to taste food and drinks.

Co-author Vicente Ramirez, a visiting scientist at Monell and a doctoral student at the University of California, said: “Here self-reports are backed up by direct measures, proving that loss of taste is a real, distinct symptom of COVID-19 that is not to be confused with smell loss.

“Taste and smell loss have been emphasized in the context of COVID-19, yet only 18 out 241 studies included an objective measurement of this sense.

"There is definitely a gap between how these symptoms are being treated and how critical they are for public health.”

The research team emphasized the need for taste assessment to become standard clinical practice, for example at an annual physical check-up.