Assessment of olfactory function in a clinical setting

Abstract

Smell detects, recognizes and identifies environmental volatiles. The aim of this work was to evaluate smell performance of a group of 350-450 health workers as part of a screening task of acute loss of smell in COVID-19 pandemic context. Smell identification (SI) and self reported judgments of odor (SRO) and taste (SRT)were evaluated. A battery of 12 commercial food odorivectors (peach, pineapple, berries, banana, mint, cherry, vanilla, coffee, vinegar (V) and others) were smelledby means of filter paper strips impregnated in 20 % V/V aqueous solutions (V at 4,5 % V/V) in four sessions (S1 to S4). In each session, SI was evaluated with a set of four randomized odorivectors: (V) and other three essences to avoid sensory adaptation. A multiple choice paradigm (MCP) with five randomized odorivector options was always offered with the algorithm of google forms (GF).SI was quantified by number of hits: 0 (anosmic, A), 1-2 (hyposmic, H) and 3-4 (normosmic, N). SRO (How do you consider to detect or discriminate odors?) and SRT (How do you consider to detect or discriminate tastes?) were self categorized as poor (I), normal (II) or high sensitivity (III). Gender (G), age (AG), smoking status(SS) were reported and body mass index (BMI) was calculated. Collected data wereanalyzed by descriptive statistics, categorical chi-square and one-way analysis of variance tests (AOV).For SI judgments very few values for A and H categories were found (S1=0 and 7; S2=1 and 21; S3=4 and 60; S4=1 and 22). Instead N encompassed 403, 378, 390 and 315 assessors respectively. SRO (I=2,9%, II=89,9% III=7,2%) and SRT (I=1,6%, II=92% III=6,4%) revealed predominantly normal self reported chemosensory functions. SI status was independent of G, AG, SS or BMI levels (chi-square values with p> 0.05) and hits depend of odorivector (AOV p< 0.01), where V, mint, cherry and vanilla were the most identified odors. MCP, several food odors and GF give auseful tool to elucidate acute loss of smell.