Acupuncture is associated with a positive effect on odour discrimination in patients with postinfectious smell loss—a controlled prospective study

Abstract Introduction Smell disorders are common in the general population and occur e.g., after infections, trauma or idiopathically Treatment strategies for smell loss range from surgery, medication to olfactory training, depending on the pathology, but they are limited This study examined the effect of acupuncture on olfactory function. Methods Sixty patients with smell loss following infections of the upper respiratory tract were included in this investigation Half of the study group were randomly assigned to verum acupuncture and the other half to sham acupuncture Olfaction was measured by means of the “Sniffin’ Sticks” test battery (odour threshold, discrimination and identification). Results Compared to sham acupuncture, verum was associated with an improvement of smell function as measured by the TDI score (p = 0.039) The improvement was largely determined by improvement in odour discrimination, and was significantly better in patients with a shorter duration of the disorder. Conclusion The present results suggest that acupuncture is an effective supplementary treatment option for patients with olfactory loss.

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The human sense of smell

Translational Medicine Reports ◽

10.4081/tmr.6579 ◽

2017 ◽

Vol 1 (2) ◽

Author(s):

Elena Cantone ◽

Filippo Ricciardiello ◽

Rossella Cuofano ◽

Giovanni Castagna ◽

Flavia Oliva ◽

...

Keyword(s):

Chemical Senses ◽

Sense Of Smell ◽

Anatomy And Physiology ◽

Olfactory Loss ◽

Current Review ◽

Smell Function ◽

The Impact ◽

Human Sense ◽

Smell Loss

The sense of smell, like taste and trigeminal senses, is a chemical sense dedicated to the perception of chemical stimulations and to the generation of responses to them. Although, from an evolutionary perspective, the chemical senses are the oldest of our senses, our knowledge on the neural processing of the three chemical senses is still incomplete and has been considerably lagging behind that of our other senses. The current review aims to give an overview about human smell function. In particular we focus on the anatomy and physiology of the olfactory system, the epidemiology and the causes of olfactory loss, and on the clinical management of olfactory disorders stressing the impact of smell loss on the quality of life. Lastly, we emphasize the importance of olfaction in every day life. In our opinion, the impairment of sense of smell should be taken into serious consideration by the clinicians, as it could be the indicator of important systemic diseases or the cause of domestic accidents.

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Molecular triggers of symptoms of parosmia and insights into the underlying mechanism

10.21203/rs.3.rs-583178/v1 ◽

2021 ◽

Author(s):

Simon Gane ◽

Jane Parker ◽

Christine Kelly

Keyword(s):

Sensory Neurons ◽

Diagnostic Tool ◽

Screening Tool ◽

Treatment Strategies ◽

Underlying Mechanism ◽

Clinical Depression ◽

Rapid Screening ◽

Olfactory Loss ◽

Smell Loss ◽

Post Infectious

Abstract The molecular stimuli that trigger a parosmic response have been identified. Parosmia is a debilitating condition in which familiar smells become distorted and unpleasant, frequently leading to clinical depression. Often a result of post infectious smell loss, incidences are increasing as COVID-19 cases escalate worldwide. Until now, there was little understanding of its pathophysiology, and the prevailing hypothesis for the underlying mechanism is a mis-wiring of olfactory sensory neurons. However, with novel application of flavour chemistry techniques as a relatively rapid screening tool for assessment of both quantitative and qualitative olfactory loss, we identified 15 different molecular triggers in coffee. This provides evidence for peripheral causation, but places constraints on the mis-wiring theory. Furthermore, it provides the basis for development of a practical diagnostic tool and treatment strategies.

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Recent smell loss is the best predictor of COVID-19 among individuals with recent respiratory symptoms

Chemical Senses ◽

10.1093/chemse/bjaa081 ◽

2020 ◽

Author(s):

Richard C Gerkin ◽

Kathrin Ohla ◽

Maria G Veldhuizen ◽

Paule V Joseph ◽

Christine E Kelly ◽

...

Keyword(s):

Symptom Onset ◽

Respiratory Symptom ◽

Respiratory Illness ◽

Cross Sectional Study ◽

Cross Sectional ◽

Logistic Regression Models ◽

Olfactory Loss ◽

Visual Analog Scales ◽

Cardinal Symptoms ◽

Smell Loss

Abstract In a preregistered, cross-sectional study we investigated whether olfactory loss is a reliable predictor of COVID-19 using 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 univariate and multivariate predictors of COVID-19 status and post-COVID-19 olfactory recovery. 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 univariate and multivariate models (ROC AUC=0.72). Additional variables provide negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms (e.g., fever). Olfactory recovery within 40 days of respiratory symptom onset was reported for ~50% of participants and was best predicted by time since respiratory symptom onset. We find that quantified smell loss is the best predictor of COVID-19 amongst those with symptoms of respiratory illness. To aid clinicians and contact tracers in identifying individuals with a high likelihood of having COVID-19, we propose a novel 0-10 scale to screen for recent olfactory loss, the ODoR-19. We find that numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4<OR<10). Once independently validated, this tool could be deployed when viral lab tests are impractical or unavailable.

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Smell disorders associated with COVID-19 infection

The Egyptian Journal of Otolaryngology ◽

10.1186/s43163-021-00095-9 ◽

2021 ◽

Vol 37 (1) ◽

Author(s):

Mohammad Waheed El-Anwar ◽

Sherif Mamdoh Mohamed ◽

Ahmed Hassan Sweed

Keyword(s):

Web Of Science ◽

Cochrane Library ◽

Upper Respiratory Tract ◽

Nasal Blockage ◽

Runny Nose ◽

Red Flag ◽

Upper Respiratory ◽

Novel Coronavirus ◽

Smell Disorders ◽

Smell Identification

Abstract Background We performed a search in the PubMed databases, Web of Science, LILACS, MEDLINE, SciELO, and Cochrane Library using the keywords COVID-19, Novel coronavirus, corona, 2019-nCoV, SARS-CoV-2, ENT, nose, anosmia, hyposmia, smell, olfactory, ORL, different ENT related symptoms. We reviewed published and peer-reviewed studies that reported the ENT manifestations in COVID-19 laboratory-confirmed positive patients. Main text Within the included 2549 COVID-19 laboratory-confirmed positive patients, smell affection was reported in 1453 patients (57%). The other reported ENT manifestations were taste disorder (49.2%), headache (42.8%), nasal blockage (26.3%), sore throat (25.7%), runny nose or rhinorrhea (21.3%), upper respiratory tract infection (URTI) (7.9%), and frequent sneezing (3.6%). Conclusion Smell affection in COVID-19 is common and could be one of the red flag signs in COVID-19 infection. With a sensitivity of utilized questionnaire in smell identification, a homogenous universal well-defined COVID-19 questionnaire is needed to make the COVID-19 data collection more sensible.

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Olfactory evaluation in hospitalised and self-isolated patients with COVID-19: a single-centre experience on 55 cases

Postgraduate Medical Journal ◽

10.1136/postgradmedj-2021-140315 ◽

2021 ◽

pp. postgradmedj-2021-140315

Author(s):

Maja Klarendic ◽

Eva Zupanic ◽

Mateja Zalaznik ◽

Dejan Georgiev ◽

Janez Tomazic ◽

...

Keyword(s):

Subjective Assessment ◽

Acute Onset ◽

Control Group ◽

Common Symptom ◽

Self Assessment ◽

Olfactory Loss ◽

Hospitalised Patients ◽

Olfactory Impairment ◽

And Control ◽

Smell Loss

BackgroundSmell loss is a common symptom of COVID-19 infection. Majority of the studies that evaluated olfactory impairment in COVID-19 used questionnaires (subjective smell evaluations) and did not compare the results with objective or semiobjective measures of smell. We performed smell testing in hospitalised and self-isolated patients with COVID-19 and control participants.MethodsFifty-five COVID-19 and 44 control participants underwent smell testing, using Burghart Snifﬁn’ Sticks ‘Screening 12 Test’. Participants also rated their smelling capability on the numerical scale. Differences between groups and correlation between smell loss and time from acute onset of symptoms were tested, as well as correlation between results of smell test and subjective assessment of smell.ResultsHospitalised patients with COVID-19 correctly determined 6.5/12 odorants compared with 10/12 in the self-isolated and 11/12 in the control group (p<0.001). Hyposmia or anosmia were present in 87.5% of hospitalised and 29.0% of self-isolated patients (p<0.001). The correlation between subjective self-assessment and results of smell testing was non-significant in both groups of patients with COVID-19, while there was a moderate positive correlation (p=0.001, Spearman’s correlation coefficient=0.499) in control participants.ConclusionContrary to some previous reports suggesting that the presence of olfactory loss may predict milder course of disease, our study found that a vast majority of hospitalised patients with COVID-19 had prominent olfactory impairment. The absence of correlation between self-rated and objective smell evaluation in patients with COVID-19 indicates that subjective smell assessment is unreliable.

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Objective sensory testing methods reveal a higher prevalence of olfactory loss in COVID-19–positive patients compared to subjective methods: A systematic review and meta-analysis

Chemical Senses ◽

10.1093/chemse/bjaa064 ◽

2020 ◽

Author(s):

Mackenzie E Hannum ◽

Vicente A Ramirez ◽

Sarah J Lipson ◽

Riley D Herriman ◽

Aurora K Toskala ◽

...

Keyword(s):

Meta Analysis ◽

Objective Measures ◽

Subjective Measures ◽

Partial Loss ◽

Olfactory Loss ◽

Point Estimates ◽

Pooled Prevalence ◽

Wide Range ◽

Subjective Measurements ◽

Smell Loss

Abstract Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), has currently infected over 6.5 million people worldwide. In response to the pandemic, numerous studies have tried to identify causes and symptoms of the disease. Emerging evidence supports recently acquired anosmia (complete loss of smell) and hyposmia (partial loss of smell) as symptoms of COVID-19, but studies of olfactory dysfunction show a wide range of prevalence, from 5% to 98%. We undertook a search of Pubmed/Medline and Google Scholar with the keywords “COVID-19,” “smell,” and/or “olfaction.” We included any study that quantified smell loss (anosmia and hyposmia) as a symptom of COVID-19. Studies were grouped and compared based on the type of method used to measure smell loss—subjective measures such as self-reported smell loss versus objective measures using rated stimuli—to determine if prevalence differed by method type. For each study, 95% confidence intervals (CIs) were calculated from point estimates of olfactory disturbances. We identified 34 articles quantifying anosmia as a symptom of COVID-19 (6 objective, 28 subjective), collected from cases identified from January 16 to April 30, 2020. The pooled prevalence estimate of smell loss was 77% when assessed through objective measurements (95% CI of 61.4-89.2%) and 44% with subjective measurements (95% CI of 32.2-57.0%). Objective measures are a more sensitive method to identify smell loss as a result of infection with SARS-CoV-2; the use of subjective measures, while expedient during the early stages of the pandemic, underestimates the true prevalence of smell loss.

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Quality of Life in Patients With Olfactory Loss Is Better Predicted by Flavor Identification Than by Orthonasal Olfactory Function

Chemical Senses ◽

10.1093/chemse/bjz027 ◽

2019 ◽

Vol 44 (6) ◽

pp. 371-377 ◽

Cited By ~ 11

Author(s):

Anna Oleszkiewicz ◽

Dahae Park ◽

Katarzyna Resler ◽

Julia Draf ◽

Anja Schulze ◽

...

Keyword(s):

Quality Of Life ◽

Predictive Value ◽

Wide Spectrum ◽

Olfactory Function ◽

Self Report ◽

Hierarchical Regression ◽

Upper Respiratory Tract ◽

Olfactory Loss ◽

Olfactory Testing

Abstract To date, most studies on the relationship between chemosensory performance and quality of life have focused on orthonasal measures of olfactory function. In the current investigation, we examined the predictive value of orthonasal and flavor identification indices of olfactory function on a wide spectrum of health and sociopsychological factors, including quality of life, life satisfaction, overall health, and depressive symptoms. Participants were 178 ENT patients (Mage = 58 ± 1), representing various causes of olfactory loss: idiopathic smell loss (n = 51; Mage = 63 ± 2), sinunasal disease (n = 27; Mage = 56 ± 3), head trauma (n = 33; Mage = 51 ± 2), and infections of the upper respiratory tract (n = 67; Mage = 59 ± 2). They completed self-report questionnaires and underwent olfactory testing using Sniffin’ Sticks (orthonasal olfactory testing) and “Taste Powder” (intraorally applied flavors for retronasal olfactory testing, additionally inducing taste sensation). Data were analyzed with hierarchical regression models wherein the first step included subjects’ sex, age, and orthonasal olfaction score. In the second step, we included the “Taste Powder” score. Tested models revealed that the first step was not significantly predicting variables of interest; however, there was an improvement of the model’s predictive value when the “Taste Powder” score was added. Results of this study suggest that flavor identification significantly improves predictions of health and sociopsychological functioning of ENT patients with various etiologies.

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Anosmia: Differential Diagnosis, Evaluation, and Management

American Journal of Rhinology and Allergy ◽

10.2500/ajra.2017.31.4403 ◽

2017 ◽

Vol 31 (1) ◽

pp. e3-e7 ◽

Cited By ~ 13

Author(s):

George A. Scangas ◽

Benjamin S. Bleier

Keyword(s):

Differential Diagnosis ◽

Negative Impact ◽

Treatment Strategies ◽

Communication Disorders ◽

The United States ◽

Current Treatment ◽

Olfactory Dysfunction ◽

Olfactory Testing ◽

Smell Disorders

The ability to scrutinize our surroundings remains heavily dependent on the sense of smell. From the ability to detect dangerous situations such as fires to the recollection of a fond memory triggered by an odor, the advantages of an intact olfactory system cannot be overstated. Outcomes studies have highlighted the profound negative impact of anosmia and parosmia on the overall quality of life. The National Institute on Deafness and Other Communication Disorders estimates that ∼1.4% of the United States population experiences chronic olfactory dysfunction and smell loss. Efforts have focused on improving both the diagnosis of olfactory dysfunction through olfactory testing and improved reporting of treatment outcomes of olfactory training. The purpose of this article was to review the differential diagnosis, workup, and current treatment strategies of anosmia and smell disorders.

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Salivary s-IgA Response to Training in Functionally Limited Elders

Journal of Aging and Physical Activity ◽

10.1123/japa.11.4.502 ◽

2003 ◽

Vol 11 (4) ◽

pp. 502-515 ◽

Cited By ~ 2

Author(s):

Mariane M. Fahlman ◽

Amy L. Morgan ◽

Nancy McNevin ◽

Debra J. Boardley ◽

Robert Topp

Keyword(s):

Mucosal Immunity ◽

Aerobic Training ◽

Exercise Program ◽

Secretion Rate ◽

Moderate Exercise ◽

Upper Respiratory Tract ◽

Iga Response ◽

Upper Respiratory ◽

Low Functioning ◽

Positive Effect

The study investigated the effects of 16 weeks of exercise training on s-IgA in a population of low-functioning elderly. Forty-nine volunteers were randomly divided into 4 groups: strength training (ST), aerobic training (AT), a combination (CT), or control (C). ST demonstrated a significant increase in s-IgA from pre to post and a significant increase in the secretion rate from pre to mid and post. AT demonstrated a significant increase in s-IgA from pre to mid to post with no subsequent change in the secretion rate. There were no significant changes across time in CT or C, but C had consistently lower s-IgA values at post than did CT, ST, or AT, and the secretion rate was significantly higher in CT than C at mid and post. The results demonstrate that moderate exercise has a positive effect on mucosal immunity as measured by s-IgA in low-functioning elderly, suggesting a greater resistance to upper respiratory-tract infection with involvement in an exercise program.

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