Association of alcohol use with olfactory function among older adults.

BACKGROUND/PURPOSE: Olfactory dysfunction (OD) has been recognized as an early biomarker for neurodegenerative diseases. Identifying behaviors that increase the risk of OD is crucial for early recognition of neurogenerative diseases. Alcohol consumption can potentially impact olfaction through its neurotoxic effects. This study aims to examine the relationship between alcohol consumption and OD, using data from the National Social Life, Health, and Aging Project (NSHAP). METHODS: This cross-sectional study was conducted on data for 2757 adults from Round 1 of NSHAP. OD was defined as correctly identifying 0-3 odors in the 5-item Sniffin' Sticks test while normal olfactory function was defined as correctly identifying 4-5 odors. Multivariable logistic regression was utilized to examine the association between alcohol consumption and OD, controlling for age, race, and comorbidities. Analyses were weighted to account for the sampling design. RESULTS: OD was present in 23.1 % of adults. The average age among those with OD was 71.2 ± 7.8 years, compared to 66.9 ± 7.2 years in those with normal olfaction. In terms of alcohol consumption, 31.1 % of adults with OD were light-to-moderate drinkers and 7.7 % were heavy drinkers, compared to 35.6 % light-to-moderate and 7.7 % heavy drinkers in the normal olfaction group. After adjusting for age, gender, race, and education, neither light-to-moderate drinking (aOR: 0.99; 95 % CI: 0.76-1.29) nor heavy drinking (aOR: 1.24; 95 % CI: 0.83-1.85) were significantly associated with OD. CONCLUSION: Alcohol consumption was not associated with OD after controlling for covariates. While this study provides insight into the relationship between alcohol consumption and OD, further research is needed due to conflicting results in previous studies.

Intranasal insulin for COVID-19-related smell loss.

BACKGROUND: Quantitative (hyposmia and anosmia) and qualitative (phantosmia and parosmia) olfactory disorders are common consequences of COVID-19 infection found in more than 38% of patients even months after resolution of acute disease. SARS-CoV-2 has tropism for angiotensin-converting enzyme 2 (ACE2) in the respiratory system, suggesting that it is the mechanism of damage to the olfactory neuroepithelium and of involvement at the central nervous system. The olfactory bulb is the organ with the highest insulin uptake in the central nervous system. Insulin increases the production of Growth Factors (GF); therefore, in this study, the administration of intranasal insulin is proposed as a viable treatment for olfactory disturbances. The aim of this study was to obtain improvement in olfaction after 4 weeks of intranasal insulin administration in a group of patients presenting chronic olfactory disturbances secondary to COVID-19 infection, quantified using the Threshold, Discrimination, and Identification (TDI) score based on the Sniffin Sticks®. METHODS: Experimental, longitudinal, prolective and prospective study of patients with a previous diagnosis of COVID-19 in the last 3-18 months and who persisted with anosmia or hyposmia. The sample size was calculated with "satulator". The intervention was performed from January to May 2022. Throughout four appointments, a baseline olfactory measurement was obtained using the TDI score based on the Sniffin Sticks® test. In the first three appointments, Gelfoam® cottonoids soaked in 40 IU of NPH insulin were placed on the nasal roof of each nostril for 15 min. Descriptive statistics, student's paired t test and a multiple linear regression were utilized to ascertain statistical significance of the outcome on the TDI score obtained on the fourth and final appointment. RESULTS: 27 patients were included in the study. Table 1 summarizes the sample characteristics. The results exhibit that 93% of the sample had an improvement. The initial mean TDI score was 67% (63-71) compared to the final mean of 83% (80-86, p < 0.01). TDI subsection analysis is shown in Table 2. There was no significant difference in pre-intervention and post-intervention glucose measurements after the intranasal insulin administration. CONCLUSIONS: The administration of intranasal insulin has promising results, pointing towards an alternative of treatment for chronic olfactory disturbances secondary to neuroepithelial damage caused by upper respiratory tract infections. Furthermore, this is the first study to use a three-point assessment of olfaction in post-COVID-19 patients, while using the Sniffin Sticks® TDI score adapted to Latin Spanish.

Efficacy of Normalising Serum Zinc Level for Patients with Olfactory Dysfunction and Zinc Deficiency.

INTRODUCTION: Zinc deficiency may worsen the severity of olfactory dysfunction; however, the relationship between serum zinc levels and therapeutic effects on olfactory dysfunction remains uncertain. This study investigated the relationship between normalising serum zinc levels and the therapeutic effects on olfactory dysfunction. METHODS: Forty-two patients diagnosed with post-infectious, post-traumatic, and idiopathic olfactory dysfunction, with serum zinc levels <70 µg/dL, were included in the study. All patients were treated with mecobalamin, tokishakuyakusan, and polaprezinc. The patients were divided into 2 groups: the zinc-normalised (≥70 µg/dL) and zinc-deficient (<70 µg/dL) groups, based on their post-treatment serum zinc levels. Olfactory test results were compared in each of the 2 groups. RESULTS: The patients were treated for a median of 133 days. The zinc-normalised group had significantly better results in all olfactory tests (detection/recognition thresholds of the T&T olfactometer, odour identification test (Open Essence), Visual Analogue Scale for olfactory dysfunction, and self-administered odour questionnaire). In contrast, only the self-administered odour questionnaire showed a significant improvement in the zinc-deficient group, with no significant differences observed in the other olfactory tests. When comparing the changes in the olfactory test scores between the 2 groups, significant differences were observed in the detection/recognition thresholds of the T&T olfactometer test and Open Essence results. CONCLUSION: These findings suggest that patients with olfactory dysfunction may have difficulty improving their olfactory function if they also have zinc deficiency. Furthermore, normalisation of zinc deficiency may contribute to the improvement of olfactory dysfunction with general treatment.

Olfaction in nasal polyp patients after Reboot surgery: an endotype-based prospective study.

PURPOSE: To report biomarkers present in the olfactory mucosa in chronic rhinosinusitis with nasal polyps (CRSwNP) in comparison with nasal polyps and to nasal mucosal tissues from control patients. To evaluate the kinetics of smell over 6 months in patients who underwent Reboot surgery. METHODS: Cohort study from May 2021 to May 2022. We collected samples of olfactory mucosa and nasal polyps from 16 CRSwNP patients and inferior turbinate samples from 20 control subjects. The study was not randomized for surgical and/or medical treatment. Samples were analyzed by Luminex and Unicap 100 to measure biomarkers of inflammation (IL1-ß, IL4, IL5, IL6, IL17, CCL3, CCL4, G-CSF, SE-IgE, total IgE and ECP). 12 of the CRSwNP patients underwent Extended Sniffin'tests at timepoints 1-4 days pre-surgery, and 1, 3 and 6 months after Reboot surgery. RESULTS: Type-2 markers were significantly elevated in OM and polyp tissue in CRSwNP (n = 16) vs. controls (n = 20), P < 0.05. TDI scores improved already 1 month (P < 0.05) after surgery and remained stable for 6 months. Type-2 inflammation in nasal polyps was associated with decreased sense of smell and taste before surgery, but improved after surgery (P = 0.048). Type-3 inflammation was present in the olfactory mucosa and was associated with a better sense of smell before surgery, but a smaller improvement of smell afterward. CONCLUSIONS: Type-2 inflammation is present in the olfactory mucosa in CRSwNP patients and is associated with smell loss. Reboot surgery, aiming to completely remove inflamed sinus mucosa, significantly improves the smell in this group of patients.

Relationship between the severity of olfactory dysfunction and serum zinc levels.

PURPOSE: Although the association between zinc deficiency and olfactory dysfunction is inconclusive, zinc deficiency causes apoptosis of the olfactory ensheathing cells which is involved in olfactory nerve turnover and axon regeneration, thereby suggesting a possible relationship. We investigated the relationship between serum zinc levels and olfactory function in patients with olfactory dysfunction. METHODS: Ninety patients who had been diagnosed with post-infectious, posttraumatic, drug-induced, neurological and idiopathic olfactory dysfunction were included. Patients were divided into zinc normal group and zinc deficiency groups according to three reference values for serum zinc levels (60, 65, 70 µg/dL). The results of olfactory tests and patient backgrounds were used to compare the differences between the two groups. RESULTS: There were significantly worse detection and recognition thresholds in the T&T olfactometer and Open Essence (odor identification test) results in the zinc deficiency group (< 60 µg/dL). In addition, significant correlations between olfactory tests (detection/recognition thresholds in the T&T olfactometer and Open Essence results) and serum zinc levels < 65 µg/dL were observed. The zinc deficiency group < 70 µg/dL with idiopathic olfactory dysfunction had significantly worse olfactory tests (detection/recognition thresholds in the T&T olfactometer and Open Essence). In addition, there was a significant correlation between the detection/recognition thresholds in the T&T olfactometer and serum zinc levels in idiopathic olfactory dysfunction. CONCLUSIONS: Our findings suggest that zinc deficiency may exacerbate the severity of olfactory dysfunction. Furthermore, idiopathic olfactory dysfunction may be partly caused by zinc deficiency.

Self-awareness of olfactory dysfunction in elderly individuals without neurodegenerative diseases.

PURPOSE: The decrease in smell in the elderly population is frequent and considered a natural process. However, sometimes it can be associated with the decline of cognitive functions, and it is considered a warning for the early stage of neurodegenerative diseases and social impairment. OBJECTIVE: To assess the prevalence of olfactory dysfunction in previous healthy elderly that attended a tertiary hospital in Brazil as escorts and the clinical alterations associated in this population. METHODS: Subjects 60 years or over attending the University Hospital of Campinas were evaluated. Each participant answered a questionnaire, followed by an otorhinolaryngological exam with flexible nasal endoscopy and the Connecticut smell test produced by the Connecticut Chemosensory Clinical Research Center (CCCRC). Elderly people with nasosinusal diseases or with a history of nasal surgery were excluded. RESULTS: Of the total of 103 participants, 16 (15.5%) reported olfactory complaints and 68 (66%) presented impairment in the olfactory test. It was observed that older individuals showed more changes in olfactory function (p = 0.001). Gender, education, lifestyle, comorbidities, medications in use and exposure to pollutants did not influence the impairment olfactory function of this population. CONCLUSIONS: There is a significant prevalence of olfactory dysfunction in the elderly population evaluated. Most of these elderlies also present an inability to identify odours, not having awareness of this olfactory impairment.

[Detection of disorders of the chemical senses-assessment of state of health by those affected]. / Erfassung von Störungen der chemischen Sinne ­ Einschätzung des Gesundheitszustands durch Betroffene.

Although hundreds of thousands of people seek medical help every year because of smell and taste disorders, the burden on patients is often underestimated by health care professionals. Numerous studies have demonstrated the impact of disorders of the chemical senses on quality of life. In clinical practice, the Questionnaire of Olfactory Disorders (QOD) has proven to be a good measure of the impact of olfactory loss on everyday life. Patient-reported outcome measures (PROMs) should therefore be used more frequently for better recording and assessing the needs of patients. In addition to education and treatment by specialized clinics, the provision and optimization of information platforms, support groups, and organizations should be promoted in Germany.

Hyposmia in COVID-19: Temporal Recovery of Smell: A Preliminary Study.

Background and Objectives: Hypo/anosmia is a characteristic symptom of COVID-19 infection. The aim of this study is to investigate the time of smell recovery and to identify a possible order of perception recovery of different odors in COVID-19 patients. Materials and Methods: A prospective observational study was conducted on not hospitalized COVID-19 patients, selected according to eligible criteria. The study was approved by the Ethical Committee. A questionnaire formulated by our team was submitted to patients in order to know the duration of the hypo/anosmia and hypo/ageusia and the order of odor recovery: vanillin (mixed olfactory/gustatory substances), phenyl ethyl alcohol (rosewater) (pure olfactory substances), eucalyptol (mixed olfactory/trigeminal substances), and eugenol (mixed olfactory/trigeminal/gustatory substances). Results: 181 patients were included. Hypo/ageusia and hypo/anosmia lasted on average 10.25 (±8.26) and 12.8 (±8.80) days, respectively. The most frequent odor recovery sequence was: (1) phenyl ethyl alcohol; (2) eucalyptol; (3) vanillin; and (4) eugenol. In COVID-19 patients, hypo/anosmia occurs more often in women and at a young age. Conclusions: This preliminary investigation highlighted novel data: there is a chronological order in perception recovery of different olfactory substances and, therefore, in the restoration of the various sensitive nerve pathways involved in the sense of smell.

Measured and self-reported olfactory function in voluntary Norwegian adults.

PURPOSE: The lack of epidemiological data on the proportion of olfactory dysfunction (OD) using comprehensive olfactory assessment in healthy adults in Scandinavia motivated to the present study which aimed to explore the proportion of OD in voluntary healthy Norwegian adults, assessed by Sniffin' Sticks, and its correlation to self-reported olfactory function. Furthermore, sociodemographic and clinical factors associated with olfactory function were analysed. METHODS: The sample included 405 Norwegian participants, aged 18-78 years, 273 women and 132 men, who underwent olfactory testing with extensive Sniffin' Sticks test, allergy testing, clinical examination with nasal endoscopy and completed a self-administered questionnaire, including self-evaluation of olfactory function on a 100 mm Visual Analogue Scale. RESULTS: We found that 37% had OD, of which 1.2% had anosmia assessed with extensive Sniffin' Sticks test. The proportion of hyposmia and anosmia increased with age. Men and participants with low education had poorer olfactory function scores. Allergy, smoking status, general health and endoscopic findings were not associated with measured olfactory function. We found no correlation between self-reported and measured olfactory function. CONCLUSIONS: This study has identified that a large proportion of our sample of voluntary healthy Norwegian adults have OD, considerably more common in older adults and somewhat more common in men and individuals with low education. The lack of correlation between self-reported and measured olfactory function highlights the importance of using validated tests for a reliable olfactory evaluation.

Olfactory training with Aromastics: olfactory and cognitive effects.

PURPOSE: The olfactory system can be successfully rehabilitated with regular, intermittent stimulation during multiple daily exposures to selected sets of odors, i.e., olfactory training (OT). OT has been repeatedly shown to be an effective tool of olfactory performance enhancement. Recent advancements in studies on OT suggest that its beneficial effects exceed olfaction and extend to specific cognitive tasks. So far, studies on OT provided compelling evidence for its effectiveness, but there is still a need to search for an optimal OT protocol. The present study examined whether increased frequency of OT leads to better outcomes in both olfactory and cognitive domains. METHOD: Fifty-five subjects (28 females; Mage = 58.2 ± 11.3 years; 26 patients with impaired olfaction) were randomly assigned to a standard (twice a day) or intense (four times a day) OT. Olfactory and cognitive measurements were taken before and after OT. RESULTS: OT performed twice a day was more effective in supporting olfactory rehabilitation and interventions targeted to verbal semantic fluency than OT performed four times a day, even more so in subjects with lower baseline scores. CONCLUSIONS: OT is effective in supporting olfactory rehabilitation and interventions targeted to verbal semantic fluency. However, it may be prone to a ceiling effect, being efficient in subjects presenting with lower baseline olfactory performance and lower verbal semantic fluency.

Reboot surgery for chronic rhinosinusitis with nasal polyposis: recurrence and smell kinetics.

OBJECTIVE: To evaluate the time for recovery of the sense of smell in patients with CRSwNP who underwent Reboot surgery compared to patients undergoing ESS in a long-term follow-up study. METHODS: Data were collected retrospectively from 168 patients with severe uncontrolled CRSwNP, who underwent revision surgery, either as Extended Endoscopic Sinus Surgery (Reboot, 140 patients) or as regular Endoscopic Sinus Surgery (ESS, 28 patients) between January 1, 2014, and December 31, 2015, aiming to compare the outcome of surgeries after 2 years of follow-up. Sense of smell was scored as judged by the patient using scores 0 to 3 reflecting a percentage estimate of remaining smell. RESULTS: Smell improved similarly in the Reboot and ESS groups over the first 9 months, which was maintained over 24 months in the Reboot, but not the ESS group (p = 0.007 after 18 months, p = 0.001 after 24 months). Furthermore, polyp recurrence rates were significantly lower in the Reboot group. CONCLUSION: Reboot surgery significantly improved olfactory function and significantly reduced nasal polyp recurrence rates over 2 years post-operatively. Therefore, Reboot should be considered for patients with uncontrolled severe CRSwNP, specifically when ESS failed, to offer long-term smell and a polyp-free status. LEVEL OF EVIDENCE: 3b.

Association between chemosensory dysfunctions and inflammatory biomarkers in patients with SARS-CoV-2 infection: a systematic review and meta-analysis.

BACKGROUND: There is evidence that chemosensory dysfunctions, including smell and taste disorders, are common findings in patients with SARS-CoV-2 infection. However, the underlying biological mechanisms and the role of inflammatory markers are still poorly understood. AIM: To investigate the inflammatory biomarkers levels in patients with COVID-19 presenting chemosensory dysfunctions. METHODS: This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. A systematic literature search was performed from January 1, 2020, to May 12, 2022. Observational studies that provided data on hematological, biochemical, infection-related indices and cellular immunity, and coagulation function in patients with COVID-19 experiencing smell and/or taste disorders were considered eligible. Effect sizes were reported as standardized mean difference (SMD) with 95% confidence intervals (CI). A negative effect size indicated that the inflammatory biomarker levels were lower among patients with chemosensory dysfunctions. RESULTS: Eleven studies were included. Patients with chemosensory disturbances had lower levels of leukocytes (SMD - 0.18, 95% CI - 0.35 to - 0.01, p = 0.04), lactate dehydrogenase (SMD - 0.45, 95% CI - 0.82 to - 0.09, p = 0.01), IL-6 (SMD - 0.25, 95% CI - 0.44 to - 0.06, p < 0.01), and C-reactive protein (SMD - 0.33, 95% CI - 0.58 to - 0.08, p < 0.01) than patients without chemosensory disturbances. CONCLUSION: Patients with SARS-CoV-2 infection who have olfactory and gustatory disorders have a lower inflammatory response than patients who do not have chemosensory alterations. The presence of these symptoms may indicate a more favorable clinical course for COVID-19.

Transient modifications of the olfactory bulb on MR follow-up of COVID-19 patients with related olfactory dysfunction.

BACKGROUND: Olfactory dysfunction (OD) has been reported with a high prevalence on mild to moderate COVID-19 patients. Previous reports suggest that volume and signal intensity of olfactory bulbs (OB) have been reported as abnormal on acute phase of COVID-19 anosmia, but a prospective MRI and clinical follow-up study of COVID-19 patients presenting with OD was missing, aiming at understanding the modification of OB during patients'follow-up. METHODS: A prospective multicenter study was conducted including 11 COVID-19 patients with OD. Patients underwent MRI and psychophysical olfactory assessments at baseline and 6-month post-COVID-19. T2 FLAIR-Signal intensity ratio (SIR) was measured between the average signal of the OB and the average signal of white matter. OB volumes and obstruction of olfactory clefts (OC) were evaluated at both evaluation times. RESULTS: The psychophysical evaluations demonstrated a 6-month recovery in 10/11 patients (90.9%). The mean values of OB-SIR significantly decreased from baseline (1.66±0.24) to 6-month follow-up (1.35±0.27), reporting a mean variation of -17.82±15.20 % (p<0.001). The mean values of OB volumes significantly decreased from baseline (49.22±10.46 mm3) to 6-month follow-up (43.70±9.88 mm3), (p=0.006). CONCLUSION: Patients with demonstrated anosmia reported abnormalities in OB imaging that may be objectively evaluated with the measurement of SIR and OB volumes. SIR and OB volumes significantly normalized when patient recovered smell. This supports the underlying mechanism of a transient inflammation of the OB as a cause of Olfactory Dysfunction in COVID-19 patients.

[Olfactory rehabilitation via retronasal olfaction using a tracheoesophageal voice prosthesis after total laryngectomy. German version]. / Olfaktorische Rehabilitation durch retronasales Riechen über die tracheoösophageale Fistel nach totaler Laryngektomie.

BACKGROUND: Despite the variety of existing methods for olfactory rehabilitation after total laryngectomy, olfactory disability remains one of the main factors limiting quality of life for laryngectomees. OBJECTIVE: Considering the need for a socially acceptable rehabilitation method that is suitable for everyday use, this study sought to elucidate whether retronasal olfaction during phonation through a tracheoesophageal voice prosthesis is possible. MATERIALS AND METHODS: The odor identification of 22 laryngectomees was assessed using the Sniffin' Sticks test battery (12 odors), while performing an established method of olfactory rehabilitation-"polite yawning"-or while transnasal expiration or phonation through the tracheoesophageal fistula (TF). To facilitate the latter, a novel Expiratory Nasal Airflow M­Maneuver (ENAMM) was developed. RESULTS: All 21 non-anosmic laryngectomees included in the study were able to identify odors retronasally. While only 6 of 22 patients (27.3%) could perform the nasal expiration through the TF, all patients could easily perform phonation using ENAMM after proper instruction. The odor identification scores with the ENAMM technique did not statistically differ from ones with "polite yawning" (5.4 ± 3.1 vs. 6.4 ± 3.2, p = 0.279). The ENAMM was easy to learn and showed a tendency of increasing olfactory scores over time, possibly due to a learning effect. CONCLUSIONS: Study results show that retronasal olfaction using a voice prosthesis after total laryngectomy is possible and suggest the potential of ENAMM as a method of olfactory rehabilitation for laryngectomy patients.

Clinical Features of Olfactory Dysfunction in COVID-19 Patients.

BACKGROUND: The aim of this study was to evaluate the subjective and objective olfactory function in coronavirus disease 2019 (COVID-19) patients and the effect of olfactory training. METHODS: A prospective cohort study was performed in 53 patients who recovered from COVID-19 and visited our tertiary hospital. Subjective olfactory function was evaluated using the 11-point Likert scale (0-10) and the Korean version of the Questionnaire of Olfactory Disorders (QOD). Objective olfactory function was evaluated using Cross-Cultural Smell Identification Test (CC-SIT). Confirmed patients were followed up after 2 months of olfactory training. RESULTS: The median, interquartile range (Q1-Q3) score of subjective olfactory function significantly deteriorated in patients with olfactory dysfunction (OD) than in those without OD, even after 3 months of onset (11-point Likert scale, 8, 6-9 vs. 10, 10-10; short version of QOD-negative statements, 19, 16-21 vs. 21, 21-21; QOD-visual analogue scale, 7, 1-13 vs. 0, 0-0; all P < 0.001). However, the objective olfactory function was not significantly different between the two groups (median, interquartile range; 11, 9-11 vs. 11, 9-11, P = 0.887). The percentage of patients with objective hyposmia (CC-SIT ≤ 10) was also not significantly different (47.4% vs. 40%, P = 0.762). OD in COVID-19 was normalized after 2 months of olfactory training in 70% of patients even after 3 months of olfactory impairment. CONCLUSION: Although subjective olfactory function is significantly decreased in the OD group, the objective olfactory function was not significantly different. Moreover, olfactory training is effective in COVID-19 patients with OD.

Validation of Olfactory Questionnaire in Koreans: an Alternative for Conventional Psychophysical Olfactory Tests.

BACKGROUND: The patients with coronavirus disease 2019 (COVID-19), a worldwide pandemic infection, frequently complain of olfactory disorders. However, psychophysical olfactory tests performed by an examiner are very difficult in these highly infectious patients. This study aimed to develop and validate a questionnaire for olfactory function that can be readily used to evaluate olfactory loss. METHODS: Fourteen smell-related questions were created based on smells familiar to Koreans. Among them, questions with a κ value of 0.6 or higher were finally selected through a test-retest reliability analysis. The correlations between the scores of the olfactory questionnaire and those of olfactory function tests (Butanol Threshold Test [BTT] and Cross Cultural Smell Identification Test [CCSIT]) were analyzed. To evaluate the predictive ability of the questionnaire and elicit cutoff values, receiver operating characteristic (ROC) curves were generated. RESULTS: Out of the 14 questions in the questionnaire, 11 (κ > 0.6) were selected for the olfactory questionnaire. We analyzed 2,273 subjects, and there was a significant correlation between the total score of the olfactory questionnaire and the BTT (r = 0.643, P < 0.001) or CCSIT (r = 0.615, P < 0.001) scores. ROC curves for the olfactory questionnaire, BTT, and CCSIT all demonstrated high predictive power to discriminate anosmia and severe hyposmia from normosmia. Regarding mild to moderate hyposmia, however, ROC curve for the olfactory questionnaire alone showed high predictive power of discrimination from normosmia. Based on the results of ROC curves among the subclasses, we suggest the classification of the total score of the questionnaire as 0-4, 5-17, 18-27, 28-41, and 42-44, for anosmia, severe hyposmia, moderate hyposmia, mild hyposmia, and normosmia, respectively. CONCLUSION: The total scores of the questionnaires correlated with the BTT and CCSIT scores. The symptom questionnaire for olfactory dysfunction may be useful as an alternative tool for olfactory function testing, when unavailable.

Objective evaluation of odor loss in COVID-19 and other suspected cases.

INTRODUCTION: COVID-19 is a pandemic disease known with one of the symptoms is sudden onset anosmia. This symptom sometimes may be the only sign of the disease, therefore it must be research widely. OBJECTIVE: We aim to evaluate odor dysfunction in COVID-19 patients objectively and safely without any risk of transmitting the disease. METHODS: The odor threshold test was performed on 105 patients hospitalized at the XXXX Training and Research Hospital on the COVID-19 pandemic service before any treatment began. Odor threshold was tested using a modification of the Connecticut Chemosensory Clinical Research Center olfactory function test. COVID-19 signs and symptoms, PCR test results, thorax computed tomography (CT) findings, and length of hospital stay were recorded. Odor tests were scored between 0-8, 0-1 anosmia, 2-3 severely hyposmia, 4 moderate hyposmia, 5 mild hyposmia, 6 and above normosmia. RESULTS: Forty-one (39%) of the 105 patients were diagnosed with COVID-19 after the PCR results. Patients with an odor threshold score < 5 were classified as "Smell-Impaired Group", patients with an odor threshold score ≥ 5 were placed in "Smell Intact Group". The incidence of female patients in smell-impaired group was significantly higher (p ˂ 0.05). The proportion of patients who were PCR-positive for COVID-19 in smell-impaired group was significantly higher (p ˂ 0.05) than in smell intact group. Among patients with an odor threshold score from 0 to 1 (anosmic; n = 15), 12 (80%) demonstrated PCR positivity (p < 0.0001). CONCLUSION: Anosmia can be predictive for coronavirus disease. Odor threshold test can be helpful for diagnosis.

Isolated olfactory cleft involvement in SARS-CoV-2 infection: prevalence and clinical correlates.

PURPOSE: Smell alterations are a symptom of COVID-19 and have been associated with olfactory cleft mucosal thickening (OCMT). Although their pathogenesis is unclear, evidences link them to viral neuroinvasive potential. This study aims at estimating the prevalence of OCMT in CT scans of COVID-19 patients and investigating its clinical correlates. METHODS: In a single-institution retrospective cross-sectional study, we included all patients hospitalized for COVID-19 undergoing head CT scan for any reason. Exclusion criteria were history of recent head trauma or chronic rhinosinusitis; opacification > 2 mm in any sinonasal space other than the olfactory cleft; CT performed during/after invasive ventilation or feeding via nasogastric tube. We recorded the prevalence of OCMT and related it to age, sex, need for invasive ventilation during hospital stay, outcome, length of hospital stay, diffusion of lung SARS-CoV-19 lesions and outcome. RESULTS: 63 eligible patients were identified (39 male, 24 female; median age 77.82 ± 17.77 years). OCMT was identified in 16 patients (25.4%; 95% CI 15.3-37.9%). Patients with OCMT had longer hospital stays (median 16 ± 4 vs. 9 ± 14.5 days, p = .009, Mann-Whitney U test) and required invasive ventilation more frequently than patients without mucosal thickening (OR 4.89, 95% CI 0.96-24.89, p = .063, Fisher's test). No other difference was observed. CONCLUSION: OCMT affects nearly one in four patients hospitalized for COVID-19. It is associated with a worse disease course irrespective of age, sex and diffusion of lung lesions, although with no direct effect on survival.

Virus load and incidence of olfactory, gustatory, respiratory, gastrointestinal disorders in COVID-19 patients: A retrospective cohort study.

OBJECTIVES: This study investigated the relationship between viral load and the incidence of olfactory and gustatory dysfunction (OD and GD), the incidence of respiratory and gastrointestinal symptoms and the recovery of OD and GD in COVID-19 patients. DESIGN: A retrospective cohort study. SETTING AND PARTICIPANTS: This study was conducted on 599 outpatients' cases in Golestan province between February and June 2020. MAIN OUTCOME MEASURES: The incidence, severity (complete or partial) and recovery time of OD and GD and their associations with cycle threshold (CT) values of SARS-CoV-2 polymerase chain reaction were assessed. RESULTS: The mean age of patients was 38.27 ± 13.62 years. The incidence of general symptoms included myalgia 70.1%, headache 51.8%, fever 47.7% and dyspnoea 21.4%. 41.9% of patients had gastrointestinal symptoms, including abdominal pain 26.5%, diarrhoea 25.2%, nausea 20.5% and vomiting 12.9%. 12.2% of patients had comorbidity. The trimester recovery rates of OD and GD were 93.94% and 94.74% respectively. The mean recovery time of OD and GD was 14.56 ± 13.37 and 13.8 ± 3.77 days respectively. The mean CT value in all patients was 27.45 ± 4.55. There were significant associations between the mean of CT value with headache (p = 0.04), GD (p = 0.002) and OD (p = 0.001). CONCLUSIONS: The finding of this study indicates a possible association between viral load with incidence of OD and GD in COVID-19 patient's cases and assures the recovery of OD/GD in these patients.

Barriers to effective health care for patients who have smell or taste disorders.

OBJECTIVES: Smell/taste disturbances are a common but underrated, under-researched and under treated sensory loss and an independent risk factor for reduced longevity. This study aimed to characterise the experience of patients with these disorders in seeking help. DESIGN: The study was designed by patients together with clinicians through a dedicated workshop and conducted as a cross-sectional survey to capture experiences in public and private healthcare settings internationally. SETTING: Primary, secondary and tertiary care. PARTICIPANTS: Any members of the public self-reporting a smell/taste disorder were invited to participate. MAIN OUTCOME MEASURES: The survey captured information including experience of getting consultations and referrals to medical professionals, treatments offered, costs incurred and related problems with mental health. RESULTS: Of 673 participants; 510 female, 160 male, three not stated, self-reported aetiology included sinonasal disease (24%), idiopathic (24%) and post-viral olfactory dysfunction (22%); true gustatory disorders were typically rare. Failure of medical professionals to recognise the problem was a key concern - 64%, 76% and 47% of GPs, ENT specialists and Neurologists acknowledged, respectively. Other issues included repeated ineffective treatments, difficulties getting referrals to secondary/tertiary care, mental health problems (60%) and a mean personal cost of £421 to seeking advice and treatment. Whilst the participants were self-selecting, however, they do represent those who are seeking help and intervention for their disorders. CONCLUSION: There is an unmet need for these patients in accessing health care including a clear need to improve education of and engagement with the medical profession in Otorhinolaryngology, General Practice and other specialties, in order to remove the current barriers they face.