Incomplete and late recovery of sudden olfactory dysfunction in COVID-19

Braz J Otorhinolaryngol. 2020 Jul-Aug;86(4):490-496. doi: 10.1016/j.bjorl.2020.05.001. Epub 2020 May 25.

Abstract

Introduction: Sudden olfactory dysfunction is a new symptom related to COVID-19, with little data on its duration or recovery rate.

Objective: To characterize patients with sudden olfactory dysfunction during the COVID-19 pandemic, especially their recovery data.

Methods: An online survey was conducted by the Brazilian Society of Otorhinolaryngology and Cervico-Facial Surgery, and Brazilian Academy of Rhinology, including doctors who assessed sudden olfactory dysfunction patients starting after February 1st, 2020. Participants were posteriorly asked by e-mail to verify data on the recovery of sudden olfactory loss and test for COVID-19 at the end of the data collection period.

Results: 253 sudden olfactory dysfunction patients were included, of which 59.1% were females with median age of 36 years, with a median follow-up period of 31 days. 183 patients (72.3%) had been tested for COVID-19, and of those 145 (79.2%) tested positive. Patients that tested positive for COVID-19 more frequently showed non-specific inflammatory symptoms (89.7% vs. 73.7%; p=0.02), a lower rate of total recovery of sudden olfactory dysfunction (52.6% vs. 70.3%; p=0.05) and a longer duration to achieve total recovery (15 days vs. 10 days; p=0.0006) than the ones who tested negative for COVID-19. Considering only positive-COVID-19 patients, individuals with sudden hyposmia completely recovered more often than the ones with sudden anosmia (68.4% vs. 50.0%; p=0.04).

Conclusion: Positive-COVID-19 patients with sudden olfactory dysfunction showed lower total recovery rate and longer duration than negative-COVID-19 patients. Additionally, total recovery was seen more frequently in positive-COVID-19 patients with sudden hyposmia than the ones with sudden anosmia.

Introdução: A perda súbita do olfato é um novo sintoma relacionado à Covid-19, porém com poucos dados sobre sua duração ou resolução.

Objetivo: Caracterizar pacientes que apresentaram perda súbita do olfato durante a pandemia da COVID-19 e em especial a sua recuperação.

Método: Pesquisa online desenvolvida pela Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial e Academia Brasileira de Rinologia direcionado aos médicos que atenderam pacientes com perda súbita do olfato com início após 1° de fevereiro de 2020. Os participantes foram questionados posteriormente por e-mail, para verificar os dados sobre a recuperação da perda súbita do olfato e teste para COVID-19, no final do período de coleta de dados.

Resultados: Foram incluídos 253 pacientes com perda súbita de olfato, 59,1% mulheres e idade mediana de 36 anos, acompanhados por 31 dias (mediana). Testagem para COVID-19 foi feita em 183 (72,3%) pacientes, 145 (79,2%) positivos e 38 (20,8%) negativos. COVID-19 positivos apresentaram sintomas inflamatórios inespecíficos mais frequentemente (89,7% vs. 73,7%; p = 0,02); menor taxa de recuperação total da perda súbita do olfato (52,6% vs. 70,3%; p = 0,05) e maior tempo para atingir a recuperação total (15 dias vs. 10 dias; p = 0,0006) comparados aos COVID-19 negativos. Considerando somente COVID-19 positivos, hiposmia súbita apresentou melhora total mais frequentemente que anosmia súbita (68,4% vs. 50,0%; p = 0,04).

Conclusão: A perda súbita do olfato em pacientes COVID-19 positivos apresentou menor taxa de recuperação total e duração mais prolongada do que em COVID-19 negativos. E a hiposmia súbita apresentou recuperação total mais frequentemente que a anosmia súbita em COVID-19 positivos.

Keywords: Anosmia; COVID-19; Olfactory disorders; Transtornos do olfato.

MeSH terms

  • Adult
  • Betacoronavirus*
  • Brazil
  • COVID-19
  • Coronavirus Infections / complications
  • Coronavirus Infections / diagnosis*
  • Coronavirus Infections / epidemiology
  • Female
  • Humans
  • Male
  • Olfaction Disorders / etiology*
  • Pandemics*
  • Pneumonia, Viral / complications
  • Pneumonia, Viral / diagnosis*
  • Pneumonia, Viral / epidemiology
  • SARS-CoV-2