High prevalence of long-term olfactory dysfunction confirmed by olfactory testing after a community COVID-19 outbreak

Abstract Purpose The prevalence of long-term olfactory and gustatory dysfunction in participants suffering from sudden chemosensory loss due to coronavirus disease 2019 (COVID-19) is unknown. Furthermore, evaluations of the reliability of participants’ self-reporting of olfactory function (SOF) and gustatory function (SGF) using extended objective psychophysical testing are missing. Methods In this population-based cohort study in a PCR-tested community in Thuringia, Germany, olfactory function was extensively examined 4 months after a COVID-19 outbreak using the “Sniffin Sticks” test battery to determine the TDIa score, i.e., the sum of results obtained for threshold, discrimination, and identification scores averaged for both nasal sides. Gustatory function was assessed using the three-drop test resulting in the gustatory composite score (CSg). The data were compared with SOF and SGF. Results Of 43 adult convalescents (median age: 68 years; 58% female) after SARS-CoV‑2 infection, 18 participants (42%) had olfactory complaints due to SOF, one participant (2%) complained of taste disturbance due to SGF. The TDIa was 22.0 ± 5.9. Normosmia, hyposmia, and anosmia were seen in 17, 18, and eight participants, respectively. TDIa correlated with SOF (rs = −0.434, p = 0.004); CSg was 23.5 ± 2.7. Normogeusia and hypogeusia were objectified in 39 and four participants, respectively. The prevalence of long-term olfactory dysfunction and gustatory dysfunction in the study group was 60.5 and 9.3%, respectively. Conclusion The SOF was reliable, especially for participants who felt a sudden chemosensory dysfunction during the outbreak. At 4 months after SARS-CoV‑2 infection, a high proportion of participants were dysosmic, whereas nearly all of them had normal taste function.

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Postinfectious Olfactory Dysfunction: Oral Steroids and Olfactory Training versus Olfactory Training Alone: Is There any Benefit from Steroids?

ORL ◽

10.1159/000516316 ◽

2021 ◽

pp. 1-8

Author(s):

Sotiria Genetzaki ◽

Evangelia Tsakiropoulou ◽

Vasilios Nikolaidis ◽

Konstantinos Markou ◽

Iordanis Konstantinidis

Keyword(s):

Olfactory Dysfunction ◽

Olfactory Function ◽

Line Treatment ◽

First Line ◽

Olfactory Testing ◽

Significant Difference ◽

Oral Steroids ◽

Group A ◽

Olfactory Training ◽

First Line Treatment

Introduction: There are limited treatment options for postinfectious olfactory dysfunction (PIOD). Olfactory training has recently been used in clinical practice, but no medical treatment is widely accepted. Although there is weak evidence for their value, some physicians use oral corticosteroids as first-line treatment. The aim of this study was to compare combined oral methylprednisolone and olfactory training with olfactory training alone in the management of PIOD. Methods: This prospective cohort study included 131 patients with PIOD over a 2-year period before the COVID-19 pandemic. Seventy-eight patients who were treated with oral methylprednisolone and olfactory training (group A) were compared with 53 patients who were treated with olfactory training only (group B). Olfactory function was evaluated with “Sniffin’ Sticks” at baseline and 2, 8, and 16 weeks after initial assessment. Patients who improved after steroid treatment underwent magnetic resonance imaging of the paranasal sinuses, skin prick tests, lung spirometry, and sputum eosinophil assessment. Results: Oral steroids improved 19.23% of patients (n = 15) of group A. History, clinical evaluation, imaging, and laboratory tests identified an inflammatory background in half of them (n = 8). The remaining 7 had no findings of nasal inflammation, and all had a short history of olfactory dysfunction. Both groups significantly improved in olfactory testing results at the end of the olfactory training scheme without significant difference between them. Conclusions: The percentage of improved patients after oral methylprednisolone was relatively low to suggest it as first-line treatment. Half of the improved patients had an underlying upper airway inflammatory condition not related to the infection that caused the acute loss of olfactory function.

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Testing olfactory dysfunction in acute and recovered COVID-19 patients: a single center study in Italy

Neurological Sciences ◽

10.1007/s10072-021-05200-7 ◽

2021 ◽

Author(s):

Jacopo Pasquini ◽

Carlo Maremmani ◽

Stefano Salvadori ◽

Vincenzo Silani ◽

Nicola Ticozzi

Keyword(s):

Acute Illness ◽

Olfactory Dysfunction ◽

Italian Population ◽

Olfactory Loss ◽

Olfactory Test ◽

Psychophysical Testing ◽

Positive Antibody ◽

Olfactory Testing ◽

High Level ◽

Acute Patients

Abstract Background Olfactory dysfunction in coronavirus disease 2019 (COVID-19) is common during acute illness and appears to last longer than other symptoms. The aim of this study was to objectively investigate olfactory dysfunction in two cohorts of patients at two different stages: during acute illness and after a median recovery of 4 months. Methods Twenty-five acutely ill patients and 26 recovered subjects were investigated. Acute patients had a molecular diagnosis of COVID-19; recovered subjects had a positive antibody assay and a negative molecular test. A 33-item psychophysical olfactory identification test tailored for the Italian population was performed. Results Median time from symptoms onset to olfactory test was 33 days in acute patients and 122 days in recovered subjects. The former scored a significantly higher number of errors at psychophysical testing (median [IQR]: 8 [13] vs 3 [2], p < 0.001) and were more frequently hyposmic (64% vs 19%, p = 0.002). Recovered subjects reported a variable time to subjective olfactory recovery, from days up to 4 months. Participants included in the study reported no significant nasal symptoms at olfactory testing. Among recovered subject who reported olfactory loss during acute COVID-19, four (27%) were still hyposmic. Demographic and clinical characteristics did not show significant associations with olfactory dysfunction. Conclusion Moderate-to-severe hospitalized patients showed a high level and frequency of olfactory dysfunction compared to recovered subjects. In the latter group, subjects who reported persisting olfactory dysfunction showed abnormal scores on psychophysical testing, indicating that, at least in some subjects, persistent hyposmia may represent a long-term sequela of COVID-19.

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Olfactory Dysfunction in Patients with Neuromyelitis Optica

Multiple Sclerosis International ◽

10.1155/2013/654501 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4 ◽

Cited By ~ 6

Author(s):

Felix Schmidt ◽

Önder Göktas ◽

Sven Jarius ◽

Brigitte Wildemann ◽

Klemens Ruprecht ◽

...

Keyword(s):

Spinal Cord ◽

Neuromyelitis Optica ◽

Autoimmune Disorder ◽

Olfactory Dysfunction ◽

Olfactory Function ◽

Clinical Spectrum ◽

Healthy Controls ◽

Optic Nerves ◽

Psychophysical Testing

Background. Neuromyelitis optica (NMO) is a severely disabling autoimmune disorder of the CNS, which mainly affects the optic nerves and spinal cord. However, recent studies have shown that extra-opticospinal are more common in NMO than previously thought.Objective. To investigate olfactory function (OF) in patients with neuromyelitis optica (NMO) versus healthy controls (HC).Methods. Psychophysical testing of the orthonasal OF was performed using theThreshold-Discrimination-Identificationtest (TDI), measuring different qualities of olfaction, in 10 unselected NMO patients and 10 HC.Results. Five of 10 NMO patients (50%) showed hyposmia, while all 10 HC were normosmic. Moreover, NMO patients had significantly lower meanTDI-scores compared to HC, based on a poorer performance in both theDiscriminationand theIdentificationsubtests.Conclusions. Our results suggest that hyposmia might be part of the expanding clinical spectrum of NMO.

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Sustained Chemosensory Dysfunction during the COVID-19 Pandemic

ORL ◽

10.1159/000515132 ◽

2021 ◽

pp. 1-10

Author(s):

Janne Schwab ◽

Caroline Damsgaard Jensen ◽

Alexander Wieck Fjaeldstad

Keyword(s):

Prognostic Factors ◽

Female Gender ◽

Olfactory Dysfunction ◽

Young Age ◽

Olfactory Function ◽

Specific Symptom ◽

Baseline Questionnaire ◽

Gustatory Function ◽

Chemosensory Function

Introduction: Chemosensory dysfunction (CD) has proven valuable in prediction of COVID-19, as it is a frequent and specific symptom of the disease. The aim of this study was to investigate the duration of CD in patients with sudden subjective olfactory and/or gustatory loss during the SARS-CoV-2 pandemic. The secondary aim was to identify possible prognostic factors for the duration of CD. Methods: An online baseline questionnaire was designed to assess subjective CD. Three rounds of follow-up questionnaires were sent out to any participants with persistent CD in 6-week intervals, prospectively assessing subjective chemosensory function and extending the follow-up time of this cohort significantly. Results: In total, 467 participants completed the baseline questionnaire. The most significant improvement and recovery of chemosensory function was observed within the first month after the initial loss. Rates became stagnant after about 2 months, and only little improvement and recovery was seen after 2–4 months. After a mean follow-up of 95.9 days (olfactory dysfunction) and 94.0 days (gustatory dysfunction), 86.7% of participants reported gustatory improvement and 82.6% reported olfactory improvement, while 55.0% reported full gustatory recovery and 43.8% reported full olfactory recovery. Female gender was associated with better improvement of gustatory function. High subjective severity of chemosensory loss was associated with lower rates of olfactory and gustatory recovery as well as improvement of olfactory function. Young age was not associated with a better prognosis. Discussion/Conclusion: Rates of improvement and recovery of chemosensory function decreased after 2–4 months after initial chemosensory loss, possibly indicating that prolonged and perhaps permanent chemosensory loss may be a complication of SARS-CoV-2 infections. High subjective severity of CD may worsen the prognosis for improvement and recovery of chemosensory function.

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Orthonasal, but not Retronasal Olfaction Is Specifically Impaired in Parkinson’s Disease

Chemical Senses ◽

10.1093/chemse/bjaa024 ◽

2020 ◽

Vol 45 (5) ◽

pp. 401-406 ◽

Cited By ~ 1

Author(s):

Emilie Aubry-Lafontaine ◽

Cécilia Tremblay ◽

Pascali Durand-Martel ◽

Nicolas Dupré ◽

Johannes Frasnelli

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Olfactory Dysfunction ◽

Olfactory Function ◽

Healthy Controls ◽

Compensatory Mechanisms ◽

Motor Disturbance ◽

Flavor Perception ◽

Olfactory Testing ◽

Retronasal Olfaction

Abstract Olfactory dysfunction (OD) in Parkinson’s disease (PD) appears several years before the presence of motor disturbance. Olfactory testing has the potential to serve as a tool for early detection of PD, but OD is not specific to PD as it affects up to 20% of the general population. Olfaction includes an orthonasal and a retronasal components; in some forms of OD, retronasal olfactory function is preserved. We aimed to evaluate whether combined testing components allows for discriminating between PD-related OD and non-Parkinsonian OD (NPOD). The objective of this study is to orthonasal and retronasal olfactory function in PD patients and compare them to a NPOD group and to healthy controls. We hypothesized that this combined testing allows to distinguish PD patients from both other groups. We included 32 PD patients, 25 NPOD patients, and 15 healthy controls. Both olfactory components were impaired in PD and NPOD patients, compared with controls; however, NPOD patients had significantly better orthonasal scores than PD patients. Furthermore, the ratio of retronasal/orthonasal score was higher in PD than in both other groups. In the NPOD group, orthonasal and retronasal scores were significantly correlated; no such correlation could be observed in PD patients. In summary, PD patients seem to rely on compensatory mechanisms for flavor perception. Combined orthonasal and retronasal olfactory testing may contribute to differentiate PD patients from patients with NPOD.

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Steroids and Olfactory Training for Postviral Olfactory Dysfunction: A Systematic Review

Frontiers in Neuroscience ◽

10.3389/fnins.2021.708510 ◽

2021 ◽

Vol 15 ◽

Author(s):

Fan Yuan ◽

Tianhao Huang ◽

Yongxiang Wei ◽

Dawei Wu

Keyword(s):

Systematic Review ◽

Olfactory Dysfunction ◽

Olfactory Function ◽

Cochrane Library ◽

Topical Steroids ◽

Olfactory Cleft ◽

Olfactory Testing ◽

Nasal Steroid ◽

Clinically Significant ◽

Olfactory Training

Background: Postviral olfactory dysfunction (PVOD) is a clinical challenge due to limited therapeutic options and poor prognosis. Both steroids and olfactory training have been proved to be effective for olfactory dysfunction with varied etiologies. We sought to perform a systematic review to summarize the evidence of steroids or olfactory training for patients with PVOD.Methods: A systematic literature review using PubMed, Embase, Cochrane Library, and Web of Science was conducted to identify studies assessing olfactory change in patients with PVOD receiving steroid or olfactory training.Results: Of the initial 273 abstracts reviewed, 20 articles with data from 2,415 patients with PVOD were included. Treatments including topical steroids, systemic steroids, classical olfactory training (COT), modified olfactory training (MOT), and olfactory training with steroid were analyzed. Both psychophysical olfactory testing and subjective symptom scores were utilized to assess the olfactory function. The routine use of nasal steroid spray alone during the management of PVOD seems to have no positive effect on olfactory dysfunction. Direct injection of steroid or nasal steroid spray into the olfactory cleft significantly improved the olfactory function in patients with PVOD. Olfactory improvement is greater than that of the natural course of the disease with short-term COT. Patients with PVOD would benefit more from long-term COT (>12 weeks). Treatment duration, various odorants, olfactory training devices, changing the types of odors periodically, different molecular odorants, and different concentrations of odorants tended to increase the efficiency of MOT. Clinically significant improvement after olfactory training was defined as an increase of threshold, discrimination, and identification (TDI) score ≥6. From week 24 to week 36, both COT and MOT groups reached the maximum therapeutic effect regarding the number of participants achieving clinically significant improvement. A combination of local or oral steroids with olfactory training is more efficient than COT only.Conclusion: Olfactory function in patients with PVOD was effectively improved through direct steroid administration in the olfactory cleft, COT, or modification of COT. The addition of topical steroids to COT therapy showed a tendency for greater olfactory improvement in patients with PVOD.

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The prevalence and the course of neuropsychiatric symptoms in patients with dementia

Norsk Epidemiologi ◽

10.5324/nje.v22i2.1570 ◽

2012 ◽

Vol 22 (2) ◽

Cited By ~ 16

Author(s):

Sverre Bergh ◽

Geir Selbæk

Keyword(s):

Cognitive Abilities ◽

Prevalence Rate ◽

Motor Behavior ◽

Neuropsychiatric Symptoms ◽

Population Based ◽

Depression And Anxiety ◽

Term Care ◽

High Prevalence ◽

Clinically Significant

Dementia is prevalent in Norway and other countries and is hallmarked by a decline in memory and other cognitive abilities. In addition to cognitive decline, the vast majority of patients with dementia experience neuropsychiatric symptoms (NPS) such as depression, agitation, psychosis, apathy, or irritability. In this review, we describe the prevalence and the course of NPS in patients with dementia, referring to results of population-based studies, studies of outpatients, and studies of patients in long-term care. For a better comparison of the included studies and for clarification, we have included studies that have assessed NPS with the Neuropsychiatric Inventory (NPI). Overall, we found a high prevalence rate of NPS. At least one NPS (NPI > 0) was present in 56% to 98% of the patients and 62% to 84% of the patients had at least one clinically significant NPS (NPI > 3). The NPS with the highest prevalence rate were apathy, irritability, agitation, depression and anxiety; while delusion, hallucination, disinhibition, aberrant motor behavior and euphoria were the least frequent NPS.

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Olfactory function as an independent prognostic factor in glioblastoma

Neurology ◽

10.1212/wnl.0000000000008744 ◽

2019 ◽

Vol 94 (5) ◽

pp. e529-e537

Author(s):

Sied Kebir ◽

Elke Hattingen ◽

Michael Niessen ◽

Laurèl Rauschenbach ◽

Rolf Fimmers ◽

...

Keyword(s):

Prognostic Factor ◽

Progression Free Survival ◽

Tumor Location ◽

Olfactory Dysfunction ◽

Olfactory Function ◽

Independent Prognostic Factor ◽

Control Cohort ◽

Olfactory Pathway ◽

Olfactory Pathways ◽

Olfactory Testing

ObjectiveTo determine the role of olfactory function in patients with glioblastoma multiforme (GBM) as a prognostic clinical measure.MethodsIn a prospective case-control study, olfactory testing was performed in 73 patients with primary GBM at baseline during first-line treatment and at later follow-ups. An age-matched control cohort consisted of 49 patients with neurologic diseases, excluding those known to affect olfactory function per se. Depending on the olfactory testing score, patients were allotted to a hyposmia group (HG) or normosmia group (NG). MRI analysis was performed to assess whether tumor location affects olfactory pathways.ResultsPatients with GBM had olfactory dysfunction significantly more often compared to the control cohort (p = 0.003). Tumor location could not explain this finding since no relevant difference in MRI-based olfactory pathway involvement was found between HG and NG (p = 0.131). Patients with olfactory dysfunction had significantly worse overall survival (OS) and progression-free survival (PFS) compared to those without dysfunction (median OS 20.9 vs 40.6 months, p = 0.035; median PFS, 9 vs 19 months, p = 0.022). Multivariate analysis in patients without MRI-based involvement of olfactory pathways confirmed olfaction is an independent prognostic factor for OS (hazard ratio [HR] 0.43; p = 0.042) and PFS (HR 0.51; p = 0.049).ConclusionThis pilot study provides the first indication that olfactory dysfunction is frequently observed in GBM and may be associated with worse survival outcome in GBM. However, validation of these results in an independent cohort is needed.

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High prevalence of long-term psychophysical olfactory dysfunction in patients with COVID-19

10.1101/2021.01.07.21249406 ◽

2021 ◽

Author(s):

Paolo Boscolo-Rizzo ◽

Anna Menegaldo ◽

Cristoforo Fabbris ◽

Giacomo Spinato ◽

Daniele Borsetto ◽

...

Keyword(s):

Olfactory Dysfunction ◽

University Of Pennsylvania ◽

Sense Of Smell ◽

Olfactory Test ◽

Culturally Adapted ◽

High Prevalence ◽

Psychophysical Evaluation ◽

Normal Sense

This study prospectively assessed the long-term prevalence of self-reported and psychophysically measured olfactory dysfunction in subjects with mild-to-moderate COVID-19. Self-reported smell or taste impairment was prospectively evaluated by SNOT-22 at diagnosis, 4-week, 8-week, and 6-month. At 6 months from the diagnosis, psychophysical evaluation of olfactory function was also performed using the 34-item culturally adapted University of Pennsylvania Smell Identification Test (CA-UPSIT). 145 completed both the 6-month subjective and psychophysical olfactory evaluation. According to CA-UPSIT, 87 subjects (60.0%) exhibited some smell dysfunction, with 54 (37.2) being mildly microsmic, 16 (11.0%) moderately microsmic, 7 (4.8%) severely microsmic, and 10 patients (6.9%) being anosmic. At the time CA-UPSIT was administered, a weak correlation was observed between the self-reported alteration of sense of smell or taste and olfactory test scores (Spearman r=-0.26). Among 112 patients who self-reported normal sense of smell at last follow-up, CA-UPSIT revealed normal smell in 46 (41.1%), mild microsmia in 46 (41.1%), moderate microsmia in 11 (9.8%), severe microsmia in 3 (2.3%), and anosmia in 6 (5.4%) patients; however, of those patients self-reporting normal smell but who were found to have hypofunction on testing, 62 out of 66 had self-reported reduction in sense of smell or taste at an earlier time point. Despite most patients report a subjectively normal sense of smell, we observed a high percentage of persistent smell dysfunction at 6 months from the diagnosis of SARS-CoV-2 infection, with 11.7% of patients being anosmic or severely microsmic. These data highlight a significant long-term rate of smell alteration in patients with previous SARS-CoV-2 infection.

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What is the Correlation between Ratings and Measures of Olfactory Function in Patients with Olfactory Loss?

American Journal of Rhinology ◽

10.1177/194589240501900606 ◽

2005 ◽

Vol 19 (6) ◽

pp. 567-571 ◽

Cited By ~ 44

Author(s):

Antje Welge-Luessen ◽

Thomas Hummel ◽

Tomislav Stojan ◽

Markus Wolfensberger

Keyword(s):

Quality Of Life ◽

Olfactory Dysfunction ◽

Olfactory Function ◽

Moderate Correlation ◽

Individual Basis ◽

Olfactory Loss ◽

Visual Analog Scales ◽

Olfactory Testing ◽

Olfactory Abilities

Background Major complaints of many patients with olfactory dysfunction relate to the impairment of quality of life. Nevertheless, it is unclear to what extent there is a correlation between ratings of olfactory abilities/impairment and olfactory function. Methods Patients with olfactory dysfunction (n = 152) were examined psychometrically using the “Sniffin’ Sticks” test battery. Ratings of olfactory function and ratings of impairment were recorded using visual analog scales. Results Following standardized olfactory testing, 78 of the 152 patients were categorized as functionally anosmic, 64 as hyposmic, and 10 as normosmic. Groups differed significantly with regard to ratings of olfactory function. Functionally anosmic patients rated impairment to be significantly higher compared with hyposmic and normosmic patients. Ratings of olfactory function correlated significantly with measured olfactory function (r = +0.57) and ratings of impairment (r = —0.30). Conclusion There was a moderate correlation between ratings and measures of olfactory function. On average, functionally anosmic patients recognized their olfactory loss, although, on an individual basis, there were striking differences between measures and ratings of olfactory function.

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