Loss of smell is not only one of the factors for early diagnosis of COVID-19, but it is also a symptom of a good prognosis of the disease, according to an international research led by scientists from the Complutense University and the San Carlos Clinical Hospital, from Madrid.
Through the study, carried out in numerous centers, with the largest sample used so far (5,868 hospitalized patients), the researchers have confirmed that although its origin is still a mystery, anosmia—loss of smell—can act as a good prognostic factor of the disease.
“These results have many implications, from the initial evaluation of patients to the ability to understand the pathophysiology. Possibly, the invasion of the nasal epithelium causes an adequate immunity to be activated avoiding cytokine storms,” explained Jesús Porta-Etessam, head of the Neurology Section of the San Carlos Clinical Hospital, professor at the Faculty of Medicine of the UCM and principal author of the work.
In addition to identifying anosmia as a good prognostic factor, researchers have determined that olfactory and taste dysfunctions are more frequent in women (12.41% vs. 8.67%), in people under 65 years of age and in patients with kidney, lung, heart, neurological or oncological disorders.
The results obtained on one of the earliest symptoms of the coronavirus can serve as criteria when classifying patients or making therapeutic decisions, according to the Complutense University of Madrid in a note released this Monday.
The conclusions of this study could be used to elaborate “risk indices” for complications, which according to Porta-Etessam would be very useful and interesting when observing, treating or evaluating the discharge of patients.
In addition to the UCM and the San Carlos Clinical Hospital, the Madrid hospitals of La Paz, Infanta Sofía, Nuestra Señora de América, Puerta de Hierro or Getafe have participated in the study; as well as the Clínico de Valladolid, Virgen de La Arraixaca (Murcia), Álvaro Cunqueiro (Vigo) and Burgos university hospitals; the Institute of Cardiology and Cardiovascular Surgery of Havana (Cuba); the IESS Los Ceibos General Hospital of the North of Guayaquil (Ecuador) and the San Carlo Clinic of Milan (Italy).