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The best COVID-19 predictor is recent smell loss: a cross-sectional study

Richard Gerkin 1 Kathrin Ohla 2 Maria Geraldine Veldhuizen 3 Paule Joseph 4 Christine Kelly 5 Alyssa Bakke 6 Kimberley Steele 4, 7 Michael Farruggia 8 Robert Pellegrino 9 Marta Pepino 10 Cédric Bouysset 11 Graciela Soler 12 Veronica Pereda-Loth 13 Michele Dibattista 14 Keiland Cooper 15 Ilja Croijmans 16 Antonella Di Pizio 17 M. Hakan Ozdener 18 Alexander Fjaeldstad 19 Cailu Lin 18 Mari Sandell 20 Preet Singh 21 V. Evelyn Brindha 22 Shannon Olsson 23 Luis Saraiva 24 Gaurav Ahuja 25 Mohammed Alwashahi 26 Surabhi Bhutani 27 Anna d'Errico 28 Marco Fornazieri 29 Jérôme Golebiowski 11 Liang-Dar Hwang 30 Lina Öztürk 3 Eugeni Roura 30 Sara Spinelli 31 Katherine Whitcroft 32 Farhoud Faraji 27 Florian Ph.S Fischmeister 33 Thomas Heinbockel 34 Julien Hsieh 35 Caroline Huart 36 Iordanis Konstantinidis 37 Anna Menini 38 Gabriella Morini 39 Jonas Olofsson 40 Carl Philpott 41 Denis Pierron 13 Vonnie Shields 42 Vera Voznessenskaya 43 Javier Albayay 44 Aytug Altundag 45 Moustafa Bensafi 46 María Adelaida Bock 47 Orietta Calcinoni 48 William Fredborg 40 Christophe Laudamiel 49 Juyun Lim 50 Johan Lundström 51 Alberto Macchi 52 Pablo Meyer 53 Shima Moein 54 Enrique Santamaría 55 Debarka Sengupta 25 Paloma Paloma Domínguez 56 Hüseyin Yanık 3 Thomas Hummel 57 John Hayes 6 Danielle Reed 18 Masha Niv 58 Steven Munger 59 Valentina Parma 60
Résumé : Background: COVID-19 has heterogeneous manifestations, though one of the most common symptoms is a sudden loss of smell (anosmia or hyposmia). We investigated whether olfactory loss is a reliable predictor of COVID-19. Methods: This preregistered, cross-sectional study used a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n=4148) or negative (C19-; n=546) COVID-19 laboratory test outcome. Logistic regression models identified singular and cumulative predictors of COVID-19 status and post-COVID-19 olfactory recovery. Results: Both C19+ and C19- groups exhibited smell loss, but it was significantly larger in C19+ participants (mean±SD, C19+: -82.5±27.2 points; C19-: -59.8±37.7). Smell loss during illness was the best predictor of COVID-19 in both single and cumulative feature models (ROC AUC=0.72), with additional features providing no significant model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms, such as fever or cough. Olfactory recovery within 40 days was reported for ~50% of participants and was best predicted by time since illness onset. Conclusions: As smell loss is the best predictor of COVID-19, we developed the ODoR-19 tool, a 0-10 scale to screen for recent olfactory loss. Numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (10
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Submitted on : Monday, November 16, 2020 - 2:47:30 PM
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Richard Gerkin, Kathrin Ohla, Maria Geraldine Veldhuizen, Paule Joseph, Christine Kelly, et al.. The best COVID-19 predictor is recent smell loss: a cross-sectional study. 2020. ⟨inserm-03007706⟩



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