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The loss of the sense of smell predicts a good prognosis in COVID-19

Although its origin remains a mystery in COVID-19, anosmia (the loss of the sense of smell) is one of the first reported symptoms of the disease. In addition to being a diagnostic factor, anosmia is now also a factor for a good prognosis, according to an international multicenter study led by the University Complutense of Madrid and the Clinic Hospital San Carlos in the largest sample of patients from various Spanish hospitals to date.


Anosmia / Shutterstock.

Anosmia is one of the first symptoms to be described in COVID-19. / Shutterstock.

UCC-UCM, 15 of March. - Patients who lose the sense of smell during COVID-19 have a better disease prognosis, according to an international study led by the University Complutense of Madrid (UCM).

Through a multicenter study of the largest sample so far (5868 hospitalized patients), the researchers confirmed their suspicions in the journal Infection: anosmia can act as a factor for a good prognosis in COVID-19.

“These results have numerous implications, from the initial patient evaluation to our ability to understand the pathophysiology. It is possible that the invasion of the nasal epithelium activates an appropriate immunity, preventing cytokine storms”, explained Jesús Porta-Etessam, Section Head of Neurology of the Clinic Hospital San Carlos, professor of the UCM Faculty of Medicine and first author of the study.

Anosmia in women and individuals younger than 65 years

In addition to concluding that anosmia is a factor for a good prognosis, the researchers also determined that olfactory and gustatory dysfunction was more common in women (12.41% vs. 8.67%), in individuals younger than 65 years and in patients with kidney, lung, heart, neurological or oncologic conditions.

The results on one of the earliest symptoms of the coronavirus can serve as a criterion when classifying patients or making therapeutic decisions.

“We could develop complication risk indices, which is of interest when observing, treating or assessing the discharge of these patients”, added Porta-Etessam.

The 20 participating institutions, in addition to the UCM and Clinic Hospital San Carlos, include the Madrid hospitals of La Paz, Infanta Sofía, Nuestra Señora de America, Puerta de Hierro and Getafe; the university hospitals Clinico de Valladolid, Virgen de La Arraixaca (Murcia), Álvaro Cunqueiro (Vigo) and that of Burgos; the Institute of Cardiology and Cardiovascular Surgery of Havana (Cuba); the General Hospital of Norte de Guayaquil IESS Los Ceibos (Ecuador); and the Clinic San Carlo of Milan (Italy).


References: Porta-Etessam, J. et al. COVID-19 anosmia and gustatory symptoms as a prognosis factor: a subanalysis of the HOPE COVID-19 (Health Outcome Predictive Evaluation for COVID-19) registry. Infection 2021 Mar 1;1-8. DOI: 10.1007/s15010-021-01587-9.



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