Feasibility and Barriers of an Olfactory Training Intervention

Olfactory dysfunction is a common issue in late-life and can be an early indicator for neurodegenerative diseases. Further, olfactory interventions not only improve olfaction but have shown promise for the delay and treatment of dementia. This study aimed to better understand the feasibility and barriers of implementing an olfactory intervention. Participants (N=23) between the ages of 52-86 (mean=71) years were recruited from the community. A demographic questionnaire showed participants were all non-smokers and identified as women (70%), men (26%), and transgender (4%). The majority were married (61%), while some were separated or divorced (17%), widowed (13%), or single (9%). Four focus groups, guided by both structured and open-ended questions, were conducted and audio-recorded with 3-7 unique participants per group. Data were transcribed, thematically analyzed, and independently coded, which resulted in three overarching themes: (1) cognitive, genetic, and environmental factors of smell, (2) methods to reduce barriers and increase the feasibility of an intervention, and (3) flexibility with technology use. Findings suggest that implementing an olfactory intervention is feasible and of interest to older populations especially when provided with detailed training protocols that have flexibility in the amount of technology used within the study. Barriers included sensitivity to smells, allergies, and dexterity issues. Reducing these barriers will facilitate implementation and decrease the likelihood of attrition. Consulting the target population provides insights into barriers, participant interest, and can assist with the development of training and intervention programs.

The Effect of Olfactory Training on Olfaction, Cognition, and Brain Function in Patients with Mild Cognitive Impairment

Background: The olfactory system is affected very early in Alzheimer’s disease and olfactory loss can already be observed in patients with mild cognitive impairment (MCI), an early stage of AD. Objective: The aim of this randomized, prospective, controlled, blinded study was to evaluate whether olfactory training (OT) may have an effect on olfactory function, cognitive impairment, and brain activation in MCI patients after a 4-month period of frequent short-term exposure to various odors. Methods: A total of 38 MCI outpatients were randomly assigned to OT or a control training condition, which were performed twice a day for 4 months. Olfactory testing, comprehensive neuropsychological assessment, and magnetic resonance imaging were performed before and after training. Results: The results suggested that OT exhibited no significant effect on olfaction and cognitive function. However, OT exhibited a positive effect on frontal lobe activation (left middle frontal gyrus and orbital-frontal cortex) but exhibited no effect on grey matter volume. Moreover, the change of olfactory scores was positively associated with the change of frontal activation. Conclusion: OT was found to have a limited effect on olfaction and cognition in patients with MCI compared to a non-OT condition but increased their functional response to odors in frontal area.

Olfactory Training and Visual Stimulation Assisted by a Web-Application for Patients With Persistent Olfactory Dysfunction After SARS-CoV-2 Infection

IntroductionWe aimed to quantify the benefit of olfactory training and visual stimulation assisted by a dedicated web application for patients who experienced olfactory dysfunction for ≥1 month after Sars-Cov-2 infection and compared it with published cohorts of spontaneous recoveries.Materials and MethodsWe performed a prospective observational study. Participants performed olfactory training and visual stimulation assisted by a dedicated web-application. Improvement was defined as a 2-point increase on a 10-point, self-assessed olfactory visual analogue scale.ResultsIn total, 1155 patients were assessable. Improvement was observed in patients who trained 4 weeks and 4 to 8 weeks with high concentration oils in 63.0% (58/92) and 72.9% (137/188) respectively, whereas in historical cohorts, a spontaneous improvement was observed in 7% to 27% without training respectively (p<.001). The benefit was observed regardless of the duration of the olfactory dysfunction. No or mild toxicity was reported by 86.6% (662/764) of patients. Severe toxicity leading to stop training was reported in 0.5% of patients.ConclusionsOlfactory training and visual stimulation assisted by a dedicated web application seems to accelerate olfactive improvement in persistent olfactory dysfunction following SARS-CoV-2 infection, especially after 30 days of olfactory training. Maximal duration of training appeared to be 8 weeks.

Sequelae of COVID 19 in taste and smell: a brief literature review

Viruses are a living being that is not formed by cellular structure. Viruses can be transmitted by direct contact with infected individuals or indirectly from contaminated surfaces. Defined as a new variety of coronaviruses, COVID 19 made the World Health Organization (WHO) declare in early 2020 a crisis in global public health. Considering the high transmissibility of this virus, it was necessary to adopt measures to prevent transmission and infection. Symptoms caused by COVID-19 are usually fever, dry cough, shortness of breath (dyspnea), tiredness (fatigue), sore throat, headache, and diarrhea. Other symptoms, to a lesser extent are anosmia (loss of smell), hyposmia (decreased smell) and ageusia (loss of sense of taste). The objective of this was to review the last two years on the sequelae of COVID 19 in taste and smell. A brief literature review was conducted in scientific articles on the sequelae of COVID 19 in taste and smell, between 2020 and 2021, in Portuguese, in the Google Scholar search database. Women and young people are the most affected by the sequelae of taste and smell caused by COVID-19. there are no specific and scientifically proven treatments to the various dysfunctions, but the most indicated is the practice of olfactory training. Studies related to dysfunctions are limited, mainly, in Brazil and when they are analyzed as sequelae. The continuity of scientific research is indispensable, because only this process will be able to elucidate the doubts that still exist and generate appropriate treatments for people who developed COVID-19.

Treatment and Prognosis of COVID-19 Associated Olfactory and Gustatory Dysfunctions

Olfactory and gustatory dysfunctions are important initial symptoms of coronavirus disease 2019 (COVID-19). However, the treatment modality for these conditions has yet to be clearly established. Therefore, most physicians have been administering empirical treatments for COVID-19-associated olfactory dysfunction, including topical or systemic steroid supplementation and olfactory training. In this literature review, we summarize the clinical course and effects of various treatments currently being conducted in patients with COVID-19-associated olfactory and gustatory dysfunctions.

Management and rehabilitation of patients with persistent olfactory disorders (hypo- and anosmia) (literature review)

We present a review of the literature and our own data on the management and rehabilitation of impairment or persis‑tent loss of the olfactory function – hypo‑ and anosmia. Approaches for restoring impaired olfactory function can be divided into olfactory training, pharmacological and physiotherapy. Smell training is carried out according to a number of protocols that differ mainly in the used arsenal of smells, as well as in the frequency of their presentation. Pharma‑cologically, it is proposed to use steroids used both topically (intranasally) and systemically; there is no common view on the effectiveness of this approach. Physiotherapy involve electrical stimulation of the olfactory filaments in the area of their exit into the nasal cavity (lateral masses of the ethmoid bone). In our opinion the most rational approach is the use of training methods using different smells.