Correlations Between Olfactory Psychophysical Scores and SARS‐CoV‐2 Viral Load in COVID‐19 Patients

Abstract

Objectives/Hypothesis: The aim of this study was to evaluate the correlations between the severity and duration of olfactory dysfunctions (OD), assessed with psychophysical tests, and the viral load on the rhino-pharyngeal swab determined with a direct method, in patients affected by coronavirus disease 2019 .Study design: Prospective cohort study. Methods: Patients underwent psychophysical olfactory assessment with Connecticut Chemosensory Clinical Research Center test and determination of the normalized viral load on nasopharyngeal swab within 10 days of the clinical onset of COVID-19.Results: Sixty COVID-19 patients were included in this study. On psychophysical testing, 12 patients (20% of the cohort) presented with anosmia, 11 (18.3%) severe hyposmia, 13 (18.3%) moderate hyposmia, and 10 (16.7%) mild hyposmia with an overall prevalence of OD of 76.7%. The overall median olfactory score was 50 (interquartile range [IQR] 30-72.5) with no significant differences between clinical severity subgroups. The median normalized viral load detected in the series was 2.56E+06 viral copies/10 6 copies of human beta-2microglobulin mRNA present in the sample (IQR 3.17E+04-1.58E+07) without any significant correlations with COVID-19 severity. The correlation between viral load and olfactory scores at baseline (R 2 = 0.0007; P = .844) and 60-day follow-up (R 2 = 0.0077; P = .519) was weak and not significant.Conclusions: The presence of OD does not seem to be useful in identifying subjects at risk for being super-spreaders or who is at risk of developing long-term OD. Similarly, the pathogenesis of OD is probably related to individual factors rather than to viral load and activity.

Prevalence of Persistent Olfactory Disorders in Patients With COVID‐19: A Psychophysical Case‐Control Study With 1‐Year Follow‐up

“…18 Similarly, risk factors for the persistence of OD have not yet been identified. 19-23 Different from any other long-term follow-up study, 5,6,8 female sex had a significant association with persistence of OD.…”

The Effects of Persistent Olfactory and Gustatory Dysfunctions on Quality of Life in Long-COVID-19 Patients

“…It has not yet been clarified what the frequency of persistent disturbances is in these groups of individuals, but if the prevalence recorded in cases of primary infection were confirmed, it would mean that this problem may not end with the immunization of the population. Second, the identification of the pathogenesis [54][55][56][57][58][59][60][61] and risk factors [2][3][4][5][6][7][8][9][10][11][12][62][63][64][65][66][67][68] for the development of persistent CD are in its infancy. For this reason, no effective therapies have yet been found for the prevention and treatment of COVID-19 related POD and PGD [69][70][71][72][73][74][75].…”

New Onset of Smell and Taste Loss Are Common Findings Also in Patients With Symptomatic COVID‐19 After Complete Vaccination

“…If this prevalence were so high even in vaccinated subjects, we could still have a high number of subjects who will require assistance for such disabling disorders. The risk factors and causes of persistence of CD in some patients have not yet been identified 16–20 . Early studies found no significant correlation between serum immunoglobulin levels and duration of olfactory disfunction 21,22 .…”