Self-reported smell and taste recovery in coronavirus disease 2019 patients: a one-year prospective study

Boscolo-Rizzo, Paolo; Guida, Francesco; Polesel, Jerry; Marcuzzo, Alberto Vito; Antonucci, Paolo; Capriotti, Vincenzo; Sacchet, Erica; Cragnolini, Fiordaliso; D’Alessandro, Andrea; Zanelli, Enrico; Marzolino, Riccardo; Lazzarin, Chiara; Tofanelli, Margherita; Gardenal, Nicoletta; Borsetto, Daniele; Hopkins, Claire; Vaira, Luigi Angelo; Tirelli, Giancarlo

PURPOSE: The aim of the present study was to estimate the 1 year prevalence and recovery rate of self-reported chemosensory dysfunction in a series of subjects with previous mild-to-moderate symptomatic COVID-19. METHODS: Prospective study based on the SNOT-22, item “sense of smell or taste” and additional outcomes. RESULTS: 268/315 patients (85.1%) completing the survey at baseline also completed the follow-up interview. The 12 months prevalence of self-reported COVID-19 associated chemosensory dysfunction was 21.3% (95% CI 16.5–26.7%). Of the 187 patients who complained of COVID-19 associated chemosensory dysfunction at baseline, 130 (69.5%; 95% CI 62.4–76.0%) reported complete resolution of smell or taste impairment, 41 (21.9%) reported a decrease in the severity, and 16 (8.6%) reported the symptom was unchanged or worse 1 year after onset. The risk of persistence was higher for patients reporting a baseline SNOT-22 score ≥ 4 (OR = 3.32; 95% CI 1.32–8.36) as well as for those requiring ≥ 22 days for a negative swab (OR = 2.18; 95% CI 1.12–4.27). CONCLUSION: A substantial proportion of patients with previous mild-to-moderate symptomatic COVID-19 characterized by new onset of chemosensory dysfunction still complained on altered sense of smell or taste 1 year after the onset.