The Efficacy of Olfactory Training as a Treatment for Olfactory Disorders Caused by Coronavirus Disease-2019: A Systematic Review and Meta-Analysis

Hwang, Se Hwan; Kim, Sun Won; Basurrah, Mohammed Abdullah; Kim, Do Hyun

doi:10.1177/19458924221150977

Cited by 17 publications

(5 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although some randomized control trials have demonstrated short-term benefits of using topical or oral corticosteroids, large-scale trials investigating their efficacy are yet to be conducted 48 . olfactory training have been shown to symptomatically improve olfactory dysfunction in both the acute and chronic phases 49 .…”

Section: Discussionmentioning

confidence: 99%

Olfactory and gustatory dysfunction, evaluation and the impact on quality of life among COVID-19 patients: a multi-centre study

AlEnazi,

Alharbi,

Althomaly

et al. 2023

Annals of Medicine &Amp; Surgery

View full text Add to dashboard Cite

Background: Olfactory and gustatory dysfunctions are frequently reported symptoms among COVID-19 patients. However, several reports suggested that there might be significant variation in the prevalence and clinical picture of chemosensory dysfunction in COVID-19 patients among different population. Objective: To study the prevalence of chemosensory dysfunction, recovery time and its impact on quality of life (QoL) among COVID-19 patients in Saudi population. Methods: This multi-center observational study was conducted at three COVID-19 centers in Saudi Arabia. Epidemiological and clinical data were extracted at baseline and within the 2-month post-infection. Olfactory and gustatory dysfunctions were assessed via valid taste and smell questionnaire, electronically collected via online survey. Short version of questionnaire of Olfactory disorders–negative statements (sQOD-NS) was used to assess the impact on QoL. Result: Total 1734 patients [926 males and 808 females, the mean age of patients was 37.7±11.6 y.] with laboratory confirmed COVID-19 were recruited for this study. Chemosensory dysfunction was reported in 56.5% cases. olfactory and gustatory dysfunctions were significantly high in females (66.2%) and age group≤ 40 years (62.2%). Among patients with olfactory dysfunction and gustatory dysfunction, recovery rate was 757 (77.2%) & 702 (71.6%) .Furthermore, the recovery time was within 8 days of onset of symptoms in 53.6% and 61.3% of olfactory dysfunction and gustatory dysfunction cases, respectively. Overall mean QoL score indicated OGD has significant impact on QoL [11.3±6.2 (P-value<0.001)]. female as compared to males (12.8±7). Females had significant impact on QoL (11.4±6.6) as compared to males [12.8±7 (P-value<0.001)]. Conclusion: chemosensory dysfunction among Saudi population was comparable to the European data and significantly higher than Asian supporting the fact that these symptoms vary as per ethnicity. Olfactory and gustatory dysfunction significantly impaired QoL and could present as an early symptom of COVID-19. Recovery rate of these symptoms can serve as a good prognostic data for patient’s counseling. Further long-term follow-up studies would lead to better understanding of prognosis and clinical outcomes.

show abstract

Section: Discussionmentioning

confidence: 99%

Olfactory and gustatory dysfunction, evaluation and the impact on quality of life among COVID-19 patients: a multi-centre study

AlEnazi,

Alharbi,

Althomaly

et al. 2023

Annals of Medicine &Amp; Surgery

View full text Add to dashboard Cite

show abstract

“…Management of post-COVID-19 OD relies primarily on consistent olfactory training (OT), with several studies confirming the efficacy of OT for post-viral OD [49,50]. Given that an improvement in olfactory abilities into the normosmic range (i.e., the transient OD group in this study) appears to dampen the magnitude of BMI change, it is therefore important to support patients in adhering to olfactory training in an effort to restore the sense of smell and alleviate the effects of OD on BMI.…”

Section: Discussionmentioning

confidence: 99%

BMI Increases in Individuals with COVID-19-Associated Olfactory Dysfunction

Vilarello,

Jacobson,

Tervo

et al. 2023

Nutrients

View full text Add to dashboard Cite

(1) Background: Reports suggest COVID-19-associated olfactory dysfunction (OD) may result in alterations in dietary behaviors and perceived weight change, but few studies using psychophysical evaluation of post-COVID-19-associated chemosensory dysfunction and body mass index (BMI) exist. The purpose of this study is to assess the impact of both quantitative and qualitative features of COVID-19-associated OD on BMI; (2) Methods: Recruitment of thirty-one participants with self-reported OD in the form of quantitative loss with and without qualitative features. Surveys with questions specific to qualitative olfactory function, Sniffin’ Sticks tests, and BMI measures were completed at two visits, one year apart. Group differences were assessed with Wilcoxon signed-rank tests and the Holm–Bonferroni method; (3) Results: Individuals with persistent quantitative OD (n = 15) and self-reported parosmia (n = 19) showed statistically significant increases in BMI after 1 year (p = 0.004, adjusted α = 0.0125; p = 0.011, adjusted α = 0.0167). Controls with transient quantitative OD (n = 16) and participants without self-reported parosmia (n = 12) showed no statistically significant changes in BMI over the same time period (p = 0.079, adjusted α = 0.05; p = 0.028, adjusted α = 0.025); (4) Conclusions: This study shows an association between COVID-19-associated OD and BMI, suggesting olfaction may play a role in altering dietary habits and nutrition in this population. Larger study cohorts are needed to further evaluate this relationship.

show abstract

“…A recent study found that individuals with a full training compliance reported a better improvement of the sense of smell [133]. Several systematic reviews and meta-analyses have shown that OT is effective during both the acute phase of the infection and post-COVID-19 [134,135]. Steroids, systemic or intranasal, are also recommended in the context of sinonasal OD, having a good level of evidence [40,50].…”

Section: Neuroepithelial Mechanism Of Anosmia In Long Covid Patientsmentioning

confidence: 99%

The Molecular Basis of Olfactory Dysfunction in COVID-19 and Long COVID

Anastassopoulou,

Davaris,

Ferous

et al. 2024

Lifestyle Genomics

View full text Add to dashboard Cite

Olfactory dysfunction (OD) is not uncommon following viral infection. Herein, we explore the interplay of host genetics with viral correlates in coronavirus disease 2019 (COVID-19)- and long COVID-related OD, and its diagnosis and treatment that remain challenging. Two genes associated with olfaction, UGT2A1 and UGT2A2, appear to be involved in COVID-19-related anosmia, a hallmark symptom of acute infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), particularly in the early stages of the pandemic. SARS-CoV-2 infects olfactory support cells, sustentacular and Bowman gland cells, that surround olfactory sensory neurons (OSNs) in the olfactory epithelium (OE) where the initial step of odor detection takes place. Anosmia primarily arises from the infection of support cells of the OE, followed by the deciliation and disruption of OE integrity, typically without OSN infection. Through the projected axons of OSNs, the virus could theoretically reach the olfactory bulb and brain, but current evidence points against this route. Intriguingly, SARS-CoV-2 infection of support cells leads to profound alterations in the nuclear architecture of OSNs, leading to the downregulation of odorant receptor-related genes, e.g., of Adcy3. Viral factors associated with the development of OD include spike protein aminoacidic changes, e.g., D614G, the first substitution that was selected early during SARS-CoV-2 evolution. More recent variants of the Omicron family are less likely to cause OD compared to Delta or Alpha, although OD has been associated with a milder disease course. OD is one of the most prevalent post-acute neurologic symptoms of SARS-CoV-2 infection. The tens of millions of people worldwide who have lingering problems with OD wait eagerly for effective new treatments that will restore their sense of smell which adds value to their quality of life.

show abstract

The Efficacy of Olfactory Training as a Treatment for Olfactory Disorders Caused by Coronavirus Disease-2019: A Systematic Review and Meta-Analysis

Cited by 17 publications

References 31 publications

Olfactory and gustatory dysfunction, evaluation and the impact on quality of life among COVID-19 patients: a multi-centre study

Olfactory and gustatory dysfunction, evaluation and the impact on quality of life among COVID-19 patients: a multi-centre study

BMI Increases in Individuals with COVID-19-Associated Olfactory Dysfunction

The Molecular Basis of Olfactory Dysfunction in COVID-19 and Long COVID

Contact Info

Product

Resources

About