Olfactory and gustatory perception in adults with long COVID.

INTRODUCTION: Olfactory dysfunction is a common symptom in COVID-19 and Long COVID. However it is unclear how well perceived impairment of olfactory and gustatory dysfunction correlate with the objectively measured intensity of olfactory dysfunction among adults with Long COVID compared to healthy never-SARS-CoV-2-infected and previously infected control cohorts. MATERIALS AND METHODS: We recruited 154 participants from an online Long COVID survey (DEFEAT Corona) for in-person examinations. Participants were allocated to three groups: Long COVID (persistent symptoms >4 weeks post-infection, n=122), Ex COVID (fully recovered, n=9), and No Covid (no history of infection, n=24). All participants completed questionnaires regarding demographics, perceived olfactory and gustatory function and underwent the standardized Sniffin Sticks olfactory test and gustatory testing. RESULTS: Long COVID participants performed significantly worse on both olfactory and gustatory function tests compared to No COVID controls. Subjective assessment of olfactory and gustatory function only weakly correlated with objective test performance in the Long COVID group (r=-0.525, p<0.001). Time since COVID-19 infection did not correlate with dysfunction severity in either Long COVID or Ex COVID group. CONCLUSIONS: Olfactory and gustatory dysfunction was more common in the Long COVID cohort than in controls. As self-perceived sensory impairment only weakly correlated with objective measures, routine screening for sensory dysfunction should be considered in Long COVID management. These impairments may significantly impact mental health and quality of life and effective treatment options like olfactory training are available.