Psychophysical assessment of olfactory and gustatory function in post-mild COVID-19 patients: A matched case-control study with 2-year follow-up

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Paolo Boscolo-Rizzo - , University of Trieste (Author)
  • Thomas Hummel - , Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Carl Gustav Carus Dresden (Author)
  • Sara Invitto - , University of Salento (Author)
  • Giacomo Spinato - , University of Padua, Azienda Unità Locale Socio Sanitaria 2-Marca Trevigiana (Author)
  • Michele Tomasoni - , Brescia Civil Hospital (Author)
  • Enzo Emanuelli - , Azienda Unità Locale Socio Sanitaria 2-Marca Trevigiana (Author)
  • Margherita Tofanelli - , University of Trieste (Author)
  • Angelo Cavicchia - , University of Trieste (Author)
  • Vittorio Grill - , University of Trieste (Author)
  • Luigi Angelo Vaira - , University of Sassari (Author)
  • Jerome R. Lechien - , University of Mons (Author)
  • Daniele Borsetto - , Cambridge University Hospitals NHS Foundation Trust (Author)
  • Jerry Polesel - , IRCCS Centro di Riferimento Oncologico - Aviano PN (Author)
  • Michele Dibattista - , University of Bari (Author)
  • Anna Menini - , International School for Advanced Studies (Author)
  • Claire Hopkins - , Guy's and St Thomas' NHS Foundation Trust (Author)
  • Giancarlo Tirelli - , University of Trieste (Author)

Abstract

Background: The aim of this study was to psychophysically evaluate the prevalence of smell and taste dysfunction 2 years after mildly symptomatic severe acute respiratory syndrome–coronavirus-2 (SARS-CoV-2) infection compared to that observed at 1-year follow-up and while considering the background of chemosensory dysfunction in the no-coronavirus disease 2019 (COVID-19) population. Method: This is a prospective case-control study on 93 patients with polymerase chain reaction (PCR)-positive SARS-CoV-2 infection and 93 matched controls. Self-reported olfactory and gustatory dysfunction was assessed by 22-item Sino-Nasal-Outcome Test (SNOT-22), item “Sense of smell or taste.” Psychophysical orthonasal and retronasal olfactory function and gustatory performance were estimated using the extended Sniffin’ Sticks test battery, 20 powdered tasteless aromas, and taste strips test, respectively. Nasal trigeminal sensitivity was assessed by sniffing a 70% solution of acetic acid. Results: The two psychophysical assessments of chemosensory function took place after a median of 409 days (range, 366–461 days) and 765 days (range, 739–800 days) from the first SARS-CoV-2–positive swab, respectively. At 2-year follow-up, cases exhibited a decrease in the prevalence of olfactory (27.9% vs. 42.0%; absolute difference, −14.0%; 95% confidence interval [CI], −21.8% to −2.6%; p = 0.016) and gustatory dysfunction (14.0% vs. 25.8%; absolute difference, −11.8%; 95% CI, −24.2% to 0.6%; p = 0.098). Subjects with prior COVID-19 were more likely than controls to have an olfactory dysfunction (27.9% vs. 10.8 %; absolute difference, 17.2%; 95% CI, 5.2% to 28.8%) but not gustatory dysfunction (14.0% vs. 9.7%; absolute difference, 4.3%; 95% CI, −5.8% to 14.4% p = 0.496) still 2 years after the infection. Overall, 3.2% of cases were still anosmic 2 years after the infection. Conclusions: Although a proportion of subjects recovered from long-lasting smell/taste dysfunction more than 1 year after COVID-19, cases still exhibited a significant excess of olfactory dysfunction 2 years after SARS-CoV-2 infection when compared to matched controls.

Details

Original languageEnglish
Pages (from-to)1864-1875
Number of pages12
JournalInternational Forum of Allergy and Rhinology
Volume13
Issue number10
Publication statusPublished - 15 Mar 2023
Peer-reviewedYes

External IDs

PubMed 36852674
WOS 000949022700001
ORCID /0000-0001-9713-0183/work/146645376

Keywords

Keywords

  • Olfaction, Olfactory disorders, Olfactory test, olfaction, olfactory disorders, olfactory test, Follow-Up Studies, Humans, COVID-19/diagnosis, Taste Disorders/diagnosis, Case-Control Studies, Smell, SARS-CoV-2, Olfaction Disorders/diagnosis