Evaluation of Olfactory Dysfunction Among COVID-19 Patients in Baghdad, Iraq.

Background SARS­CoV­2 (COVID-19) causes olfactory dysfunction which is characterized by anosmia or hyposmia. Characterization of olfactory dysfunction has added value to the diagnosis and prognosis of the disease. Nevertheless, scarce information exists about COVID-19 patients suffering from olfactory dysfunction in Iraq. This study aimed to identify olfactory dysfunction (anosmia or hyposmia) in Iraqi COVID-19 patients and examine their response to smell exercise at Baghdad Medical City Complex, Baghdad, Iraq. Methodology This case series prospective study involving 300 patients (160 males and 140 females) with COVID-19 infection was conducted from June 1, 2020, to October 1, 2021. We recorded signs and symptoms of COVID-19 among patients by examining olfactory dysfunction, n-butanol olfaction test, and smell test exercise. Results Anosmia and hyposmia were found in 69.3% and 30.7% of the patients, respectively; of these, 65.7% were of sudden onset. The association between olfactory dysfunction and smoking was not significant. The most frequent signs and symptoms of COVID-19 were fatigue, fever, loss of taste, myalgia, headache, sore throat, cough, depressed appetite, dyspnea, nausea, abdominal pain, and diarrhea. The highest frequencies of occurrence of anosmia (30.7%) and hyposmia (13.3%) were in the age group of 31-40 years. The majority (47.7%) of patients with olfactory dysfunction recovered within one month of COVID-19 onset. The rest of the patients recovered within one month to 16 months. The most commonly encountered ear, nose, and throat symptoms were nasal obstruction, rhinorrhea, and facial/ear pain. The percentages of patients with anosmia and hyposmia recovering with smell exercise were significant at 64.7% and 25.3%, respectively. Conclusions The prognosis of olfactory dysfunction in COVID-19 patients was good as most cases recovered within a short period with concomitant smell exercise. Olfactory dysfunction in the majority of COVID-19 patients was self-limiting in young age groups, albeit in association with the non-severity of the disease. Being an important public health issue, examining olfactory dysfunction aspects should be considered in the diagnosis, prognosis, and treatment protocols of COVID-19 patients. In-depth exploration is needed to examine olfactory and gustatory dysfunction in patients suffering from severe COVID-19.

Valid olfactory impairment tests can help identify mild cognitive impairment: an updated meta-analysis.

Background: Olfactory testing is emerging as a potentially effective screening method for identifying mild cognitive impairment in the elderly population. Objective: Olfactory impairment is comorbid with mild cognitive impairment (MCI) in older adults but is not well-documented in subdomains of either olfactory or subtypes of cognitive impairments in older adults. This meta-analysis was aimed at synthesizing the differentiated relationships with updated studies. Methods: A systematic search was conducted in seven databases from their availability to April 2023. A total of 38 publications were included, including 3,828 MCI patients and 8,160 healthy older adults. Two investigators independently performed the literature review, quality assessment, and data extraction. The meta-analyses were conducted with Stata to estimate the average effects and causes of the heterogeneity. Results: Compared to normal adults, MCI patients had severe impairments in olfactory function and severe deficits in specific domains of odor identification and discrimination. Olfactory impairment was more severe in patients with amnestic mild cognitive impairment than in patients with non-amnestic MCI. Diverse test instruments of olfactory function caused large heterogeneity in effect sizes. Conclusion: Valid olfactory tests can be complementary tools for accurate screening of MCI in older adults.

Disparity of smell tests in Alzheimer's disease and other neurodegenerative disorders: a systematic review and meta-analysis.

Background: There are discrepancies of olfactory impairment between Alzheimer's disease (AD) and other neurodegenerative disorders. Olfactory deficits may be a potential marker for early and differential diagnosis of AD. We aimed to assess olfactory functions in patients with AD and other neurodegenerative disorders, to further evaluate the smell tests using subgroup analysis, and to explore moderating factors affecting olfactory performance. Methods: Cross-sectional studies relating to olfactory assessment for both AD and other neurodegenerative disorders published before 27 July 2022 in English, were searched on PubMed, Embase and Cochrane. After literature screening and quality assessment, meta-analyses were conducted using stata14.0 software. Results: Forty-two articles involving 12 smell tests that evaluated 2,569 AD patients were included. It was revealed that smell tests could distinguish AD from mild cognitive impairment (MCI), Lewy body disease (LBD), depression, and vascular dementia (VaD), but not from diseases such as frontotemporal dementia (FTD). Our finding indicated that in discriminating AD from MCI, the University of Pennsylvania Smell Identification Test (UPSIT) was most frequently used (95%CI: -1.12 to -0.89), while the Brief Smell Identification Test (B-SIT), was the most widely used method in AD vs. LBD group. Further subgroup analyses indicated that the methods of smell test used contributed to the heterogeneity in olfactory threshold and discrimination scores in group AD vs. MCI. While the moderating variables including age, MMSE scores, education years in AD vs. LBD, were account for heterogeneity across studies. Conclusion: Our finding suggests smell tests have potential value in early differential diagnosis of AD. UPSIT and its simplified variant, B-SIT, are widely used methods in the analyses. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php? RecordID = 357970 (PROSPERO, registration number CRD42022357970).

The 8-item NHANES pocket smell test®: Normative data.

This study provides normative data useful for interpreting scores from the Pocket Smell Test® (PST®), a brief "scratch & sniff" neuropsychological olfactory screening test comprised of 8 items from the 40-item University of Pennsylvania Smell Identification Test (UPSIT®). We combined 3,485 PST® scores from the 2013 to 2014 National Health and Nutrition Survey (NHANES) of persons 40 years of age and older with equivalent PST® items extracted from an UPSIT® database of 3,900 persons ranging in age from 5 to 99 years. Decade-related age- and gender-adjusted percentile normative data were established across the entire age spectrum. Cut-points for defining clinically useful categories of anosmia, probable microsmia, and normosmia were determined using receiver operating characteristic (ROC) curve analyses. An age-related decline in test scores was evident for both sexes after the age of 40 years, with women outperforming men. Based on the ROC analyses, subjects scoring 3 or less (AUC = 0.81) defines anosmia. Regardless of sex, a score of 7 or 8 on the N-PST® signifies normal function (AUC of 0.71). Probable microsmia is classified as scores extending from 3 to 6. These data provide an accurate means for interpreting PST® scores within a number of clinical and applied settings.

Low to moderate genetic influences on the rapid smell test SCENTinel™.

SCENTinel™ - a rapid, inexpensive smell test that measures odor detection, intensity, identification, and pleasantness - was developed for population-wide screening of smell function. SCENTinel™ was previously found to screen for multiple types of smell disorders. However, the effect of genetic variability on SCENTinel™ test performance is unknown, which could affect the test's validity. This study assessed performance of SCENTinel™ in a large group of individuals with a normal sense of smell to determine the test-retest reliability and the heritability of SCENTinel™ test performance. One thousand participants (36 [IQR 26-52] years old, 72% female, 80% white) completed a SCENTinel™ test at the 2021 and 2022 Twins Days Festivals in Twinsburg, OH, and 118 of those completed a SCENTinel™ test on each of the festival's two days. Participants comprised 55% percent monozygotic twins, 13% dizygotic twins, 0.4% triplets, and 36% singletons. We found that 97% of participants passed the SCENTinel™ test. Test-retest reliability ranged from 0.57 to 0.71 for SCENTinel™ subtests. Broad-sense heritability, based on 246 monozygotic and 62 dizygotic twin dyads, was low for odor intensity (r=0.03) and moderate for odor pleasantness (r=0.4). Together, this study suggests that SCENTinel™ is a reliable smell test with only moderate heritability effects, which further supports its utility for population-wide screening for smell function.

On the relationship between neurocognitive measures and olfactory dysfunction in COVID-19 patients with and without anosmia.

One of the predominant symptoms of the COVID-19 virus is the complete (anosmia) or partial (hyposmia) loss of smell. Anosmia may be a critical neurocognitive symptom because there is an empirically demonstrated association of anosmia with neurodegenerative diseases like Parkinson's disease, Alzheimer's disease, etc. The present study assessed the neurocognitive disorder patterns in recovered COVID-19 patients who either self-reported anosmia or its absence. Of the 60 adult participants (n = 32 males, n = 28 females; Mage = 20.78 years, range = 18-31 years), 15 reported COVID-19 induced anosmia, 15 reported COVID-19 without anosmia, and 30 reported not having contracted COVID-19. The participants were first administered a 10-item smell test, and analysis of variance revealed significantly better scores for the control group than the other two groups. Further, there was no significant difference in smell scores between the patients who self-reported anosmia or denied it. This statistical pattern was consistent across all neuropsychological tests: short- and long-term verbal memory, digit span, Trail Making, and a self-report 46-item neurocognitive scale. Regardless of the self-report of anosmia or denial, all thirty COVID-19 patients scored significantly poorer than the control group on all of the tests and neurocognitive scale. In summary, the self-report of anosmia appears to be unreliable, and the COVID-19 patients who were found to be anosmic on the initial objective smell test demonstrated poorer neuropsychological performance than controls.

Proof-of-concept: SCENTinel 1.1 rapidly discriminates COVID-19-related olfactory disorders.

It is estimated that 20%-67% of those with COVID-19 develop olfactory disorders, depending on the SARS-CoV-2 variant. However, there is an absence of quick, population-wide olfactory tests to screen for olfactory disorders. The purpose of this study was to provide a proof-of-concept that SCENTinel 1.1, a rapid, inexpensive, population-wide olfactory test, can discriminate between anosmia (total smell loss), hyposmia (reduced sense of smell), parosmia (distorted odor perception), and phantosmia (odor sensation without a source). Participants were mailed a SCENTinel 1.1 test, which measures odor detection, intensity, identification, and pleasantness, using one of 4 possible odors. Those who completed the test (N = 287) were divided into groups based on their self-reported olfactory function: quantitative olfactory disorder only (anosmia or hyposmia, N = 135), qualitative olfactory disorder only (parosmia and/or phantosmia; N = 86), and normosmia (normal sense of smell; N = 66). SCENTinel 1.1 accurately discriminates quantitative olfactory disorders, qualitative olfactory disorders, and normosmia groups. When olfactory disorders were assessed individually, SCENTinel 1.1 discriminates between hyposmia, parosmia, and anosmia. Participants with parosmia rated common odors less pleasant than those without parosmia. We provide proof-of-concept that SCENTinel 1.1, a rapid smell test, can discriminate quantitative and qualitative olfactory disorders, and is the only direct test to rapidly discriminate parosmia.

Unmasking the 'Asymptomatic' COVID-19: A Nose Question.

The new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has high infectivity, often masked by asymptomatic carriers, which allows it to spread rapidly and become a pandemic. Attempts to slow the pandemic at this stage depend on the ability to unmask asymptomatic carriers. The rapid diagnosis of active coronavirus disease 2019 (COVID-19) infection is one of the cornerstones of pandemic control, as the nasal cavity is the main gateway for SARS-CoV-2 entry and altered sense of smell is a feature of the current virus. In the present study, we therefore tested the olfactory threshold coupled with heart-lung parameters in subjects undergoing traditional molecular testing, resulting in a significantly different score between asymptomatic subjects and healthy controls. In total, 82% of asymptomatic positives showed olfactory impairment; of these, 46% had severe hyposmia and 7% had anosmia, while in the control 9% had severe hyposmia and 0% had anosmia, respectively, which agrees with heart rate, breathing rate, and blood pressure parameter variations. The olfactory test coupled with physiological parameters may help to identify asymptomatic people. In conclusion, our results suggest that most asymptomatic individuals could be unmasked by mass olfactory rapid threshold screening and then referred to traditional slower diagnostic tests.

Analysis of Prevalence and Predictive Factors of Long-Lasting Olfactory and Gustatory Dysfunction in COVID-19 Patients.

BACKGROUND: Although smell and taste disorders are highly prevalent symptoms of COVID-19 infection, the predictive factors leading to long-lasting chemosensory dysfunction are still poorly understood. METHODS: 102 out of 421 (24.2%) mildly symptomatic COVID-19 patients completed a second questionnaire about the evolution of their symptoms one year after the infection using visual analog scales (VAS). A subgroup of 69 patients also underwent psychophysical evaluation of olfactory function through UPSIT. RESULTS: The prevalence of chemosensory dysfunction decreased from 82.4% to 45.1% after 12 months, with 46.1% of patients reporting a complete recovery. Patients older than 40 years (OR = 0.20; 95% CI: [0.07, 0.56]) and with a duration of loss of smell longer than four weeks saw a lower odds ratio for recovery (OR = 0.27; 95% CI: [0.10, 0.76]). In addition, 28 patients (35.9%) reported suffering from parosmia, which was associated with moderate to severe taste dysfunction at the baseline (OR = 7.80; 95% CI: [1.70, 35.8]). Among the 69 subjects who underwent the UPSIT, 57 (82.6%) presented some degree of smell dysfunction, showing a moderate correlation with self-reported VAS (r = -0.36, p = 0.0027). CONCLUSION: A clinically relevant number of subjects reported persistent chemosensory dysfunction and parosmia one year after COVID-19 infection, with a moderate correlation with psychophysical olfactory tests.

Olfactory dysfunction is common in classical infratentorial superficial siderosis of the central nervous system.

BACKGROUND: Established features of classical infratentorial superficial siderosis (iSS) include hearing loss, impaired balance, myelopathy and, less commonly, cognitive compromise. Olfactory function may be affected but dedicated studies are lacking. This study aimed to assess the prevalence of olfactory dysfunction in iSS and correlate it with auditory and cognitive functions. METHODS: Ten participants with iSS completed the University of Pennsylvania Smell Identification Test (UPSIT). The scores were compared with population norms; regression analysis was performed to evaluate associations between the scores and hearing thresholds (3-frequency average, 3FA) or the number of cognitive domains impaired. Imaging was reviewed for haemosiderin distribution and to exclude other causes of olfactory and hearing dysfunction. RESULTS: Eight of ten participants were male; the mean (standard deviation, SD) age was 52.5 (14.5) years. Olfactory hypofunction was identified in all participants and in six (60%) was moderate or completely absent. The mean UPSIT score of 25.5 (7.8) was significantly worse than population norms (difference in means - 10.0; 95% CI - 15.6 to - 4.4). Linear regression identified an association between UPSIT and hearing thresholds (R = 0.75; p = 0.013). The score decreases by 0.157 units (95% CI - 0.31 to - 0.002; p = 0.048) per unit increase in 3FA, after adjusting for hearing loss risk factors. There was no statistically significant association between UPSIT and cognitive function (R = 0.383; p = 0.397). CONCLUSION: We report a high prevalence of olfactory dysfunction in iSS, the severity of which correlated with hearing loss. Olfaction appears to be a core feature of the iSS clinical syndrome that should be assessed routinely.

Association Between Satisfaction with Nasal Appearance and Olfactory Function in Patients Undergoing Septorhinoplasty Surgery.

BACKGROUND: Any surgery has some complications, and septorhinoplasty is not an exception. The aim of this study was to highlight the relationship between satisfaction with nasal appearance and olfactory function in patients undergoing septorhinoplasty. METHODS: This is a cohort study. In this study, 384 patients aged 18 to 45 years who referred to the Ear, Nose and Throat department at Rasoul Akram hospital and private clinics in 2019 underwent septorhinoplasty. All patients were tested by the Persian Smell Identification Test (PSIT) or Rapid Smell Test (RST) before surgery. They were also reassessed one and three months after surgery. Those patients with dissatisfaction with olfactory function after surgery were also followed up for three months and assessed by PSIT or RST to determine their olfactory dysfunction. RESULTS: One month after surgery, 73.5% of patients who were not satisfied with their nasal appearance also complained about the olfactory sense. In addition, 1.5% of patients who were satisfied with their nasal appearance also complained about the olfactory sense. There was a significant difference regarding complaints of the olfactory sense between patients satisfied with their nasal appearance and those not satisfied with their appearance (P<0.05). Three months after surgery, 78.9% patients who were not pleased with their nasal appearance also had an olfactory complaint. Besides, 0.9% of patients who were pleased with their nasal shape also had an olfactory complaint. There was a significant difference regarding olfactory complaints between patients who were pleased with their nasal shape and those who were not (P<0.05). CONCLUSION: One and three months after septorhinoplasty, most patients who are satisfied with their nasal appearance have no complaints about their olfactory sense, and most patients who are not satisfied with their nasal appearance complain about the olfactory sense. An appropriate outcome of septorhinoplasty with regard to improving olfactory functional status is accompanied by patients' satisfaction level of achieving good nasal appearance.

Proportion of New Onset of Anosmia and Its Diagnostic Significance in COVID-19.

OBJECTIVE: This study aimed to know the proportion of new-onset of anosmia and to find its diagnostic significance in coronavirus disease 2019 (COVID-19) patients attending the hospital. Study design and duration: The Indian smell test in COVID-19 by AIIMS Raipur (ISCA-R) was developed for evaluating olfaction in the Indian population. The olfactory function was assessed using the corona scale on anosmia AIIMS Raipur (COSANAr). RESULTS: Out of 256 patients, 171 were males and 85 were females. In the majority of the patients, 75 (29.29%), the COSANAr score "0" was higher on the day of admission compared to the score "3" on the day of discharge with 61 (23.82%) patients. There was no improvement in 134 (52.34%) patients with loss of smell at the time of discharge. CONCLUSION: This study is a step forward in identifying anosmia by ISCA-R at the early stages of the COVID phase. The COSANAr is affordable for the Indian population. It is noticed that most of the patients have mild hyposmia at the time of discharge and anosmia at the admission time.

The 8-Odorant Barcelona Olfactory Test (BOT-8): Validation of a New Test in the Spanish Population During the COVID-19 Pandemic.

BACKGROUND AND OBJECTIVE: Most smell tests are difficult to implement in daily clinical practice owing to their long duration. The aim of the present study was to develop and validate a short, easy-to-perform, and reusable smell test to be implemented during the COVID-19 pandemic. METHODS: The study population comprised 120 healthy adults and 195 patients with self-reported olfactory dysfunction (OD). The 8-Odorant Barcelona Olfactory Test (BOT-8) was used for detection, memory/recognition, and forced-choice identification. In addition, a rose threshold test was performed, and a visual analog scale was applied. The Smell Diskettes Olfaction Test (SDOT) was used for correlation in healthy volunteers, and the University of Pennsylvania Smell Identification Test (UPSIT) was used for patients with OD to establish cut-offs for anosmia and hyposmia. In order to take account of the COVID-19 pandemic, disposable cotton swabs with odorants were compared with the original test. RESULTS: In healthy persons, the mean (SD) BOT-8 score was 100% for detection, 94.5% (1.07) for memory/recognition, and 89.6% (0.86) for identification. In patients with OD, the equivalent values were 86% (32.8), 73.2% (37.9), and 77.1% (34.2), respectively. BOT-8 demonstrated good test-retest reliability, with agreement of 96.7% and a quadratic k of 0.84 (P<.001). A strong correlation was observed between BOT-8 and SDOT (r=0.67, P<.001) and UPSIT (r=0.86, P<.001). Agreement was excellent for disposable cotton swabs, with a k of 0.79 compared with the original test. The cut-off point for anosmia was ≤3 (area under the curve, 0.83; sensitivity, 0.673; specificity, 0.993). CONCLUSION: BOT-8 offers an efficient and fast method for assessment of smell threshold, detection, memory, and identification in daily clinical practice. Disposable cotton swabs with odorants proved to be useful and safe during the COVID-19 pandemic.

Proof-of-concept: SCENTinel 1.1 rapidly discriminates COVID-19 related olfactory disorders.

It is estimated that 20-67% of those with COVID-19 develop olfactory disorders, depending on the SARS-CoV-2 variant. However, there is an absence of quick, population-wide olfactory tests to screen for olfactory disorders. The purpose of this study was to provide a proof-of-concept that SCENTinel 1.1, a rapid, inexpensive, population-wide olfactory test, can discriminate between anosmia (total smell loss), hyposmia (reduced sense of smell), parosmia (distorted odor perception), and phantosmia (odor sensation without a source). Participants were mailed a SCENTinel 1.1 test, which measures odor detection, intensity, identification, and pleasantness, using one of four possible odors. Those who completed the test (N = 381) were divided into groups based on their self-reported olfactory function: quantitative olfactory disorder (anosmia or hyposmia, N = 135), qualitative olfactory disorder (parosmia and/or phantosmia; N = 86), and normosmia (normal sense of smell; N = 66). SCENTinel 1.1 accurately discriminates quantitative olfactory disorders, qualitative olfactory disorders, and normosmia groups. When olfactory disorders were assessed individually, SCENTinel 1.1 discriminates between hyposmia, parosmia and anosmia. Participants with parosmia rated common odors less pleasant than those without parosmia. We provide proof-of-concept that SCENTinel 1.1, a rapid smell test, can discriminate quantitative and qualitative olfactory disorders, and is the only direct test to rapidly discriminate parosmia.

Validation of Iranian Smell Identification Test for screening of mild cognitive impairment and Alzheimer's disease.

BACKGROUND: According to the World Alzheimer Report 2019, an estimated 50 million people worldwide are living with dementia. The smell test is a method for early detection of Alzheimer's disease (AD) as an inexpensive, simple, and noninvasive screening tool. This study aimed to evaluate the accuracy of the Iran Smell Identification Test (Iran-SIT) in discriminating patients with AD, with mild cognitive impairment (MCI), and the healthy subjects. METHODS: In this study, 42 patients with AD, 33 with MCI, and 32 healthy controls were recruited from the referral Memory Clinic of Tehran University of Medical Sciences. The olfactory function was examined with six odors through Iran-SIT. RESULTS: We found a significant difference among the olfactory function in subjects with normal cognitive status, that of those with MCI and those with AD (p < 0.001). The cutoff point for the diagnosis of AD was (sensitivity and specificity were, respectively, 85.7 and 90.8%), and (Sensitivity and specificity were, respectively, 93.9 and 100%) for MCI. CONCLUSION: These results suggest that Iran-SIT is a valid biomarker and practical screening tool, with simple, inexpensive, and readily available for use in combination with neuropsychological tools and neuroimaging for early detection of AD.

Screening for Olfactory Dysfunction in COVID-19 Patients Using Quick Smell Identification Test.

OBJECTIVE: To determine the prevalence of OD in the confirmed case with COVID-19 among our population using quick smell identification test (Q-SIT) as screening tool. METHODS: Cross- sectional study carried out in Qatif area-Saudi Arabia among adult hospitalized patient with confirm COVID-19 during the period between May and July, 2020. All adults confirmed COVID-19 patients were interviewed for history of current disease and associated symptoms as well as performing Q-SIT. Participants who had history of olfactory dysfunction, and critical cases required ICU admission were excluded. RESULTS: The prevalence of OD among COVID-19 cases was (16.3%) in our population using Q-SIT compared to (27.4%) for self-reported symptom. Females were having higher prevalence in compare to males (30.5% and 11.1%) respectively; which was statistically significant (P < 0.001). The patients reported higher prevalence of ageusia (31.9%) with significant association with OD (P < 0.001). Q-SIT showed high positive and negative predictive value in detecting OD among patients with COVID-19 (84% and 93% respectively). CONCLUSION: Q-SIT is a useful, validated and easy to apply tool for screening OD among patients with COVID-19. Some patients presented solely with this symptom which can occurs unnoticed in COVID-19 patients, and there for required objective test for detection.

The 8-Odorant Barcelona Olfactory Test(BOT-8): Validation of a New Test in the Spanish Population During the COVID-19 Pandemic

Background: Most smell tests are difficult to implement in daily clinical practice owing to their long duration. The aim of the present study was to develop and validate a short, easy-to-perform, and reusable smell test to be implemented during the COVID-19 pandemic. Methods: The study population comprised 120 healthy adults and 195 patients with self-reported olfactory dysfunction (OD). The 8-Odorant Barcelona Olfactory Test (BOT-8) was used for detection, memory/recognition, and forced-choice identification. In addition, a rose threshold test was performed, and a visual analog scale was applied. The Smell Diskettes Olfaction Test (SDOT) was used for correlation in healthy volunteers, and the University of Pennsylvania Smell Identification Test (UPSIT) was used for patients with OD to establish cut-offs for anosmia and hyposmia. In order to take account of the COVID-19 pandemic, disposable cotton swabs with odorants were compared with the original test. Results: In healthy persons, the mean (SD) BOT-8 score was 100% for detection, 94.5% (1.07) for memory/recognition, and 89.6% (0.86) for identification. In patients with OD, the equivalent values were 86% (32.8), 73.2% (37.9), and 77.1% (34.2), respectively. BOT-8 demonstrated good test-retest reliability, with agreement of 96.7% and a quadratic k of 0.84 (P<.001). A strong correlation was observed between BOT-8 and SDOT (r=0.67, P<.001) and UPSIT (r=0.86, P<.001). Agreement was excellent for disposable cotton swabs, with a k of 0.79 compared with the original test. The cut-off point for anosmia was ≤3 (area under the curve, 0.83; sensitivity, 0.673; specificity, 0.993). Conclusions: BOT-8 offers an efficient and fast method for assessment of smell threshold, detection, memory, and identification in daily clinical practice. Disposable cotton swabs with odorants proved to be useful and safe during the COVID-19 pandemic (AU)

Introducción: Las olfatometrías son difíciles de implementar en la práctica clínica diaria por su larga duración. El objetivo del presente estudio fue desarrollar y validar una prueba simple, fácil y reutilizable para ser utilizada durante la pandemia de COVID-19. Métodos: Se incluyeron 120 voluntarios sanos ≥18 años y 195 pacientes con disfunción olfatoria (DO) autoreportada. Se utilizó el Barcelona Olfactory Test (BOT-8) con 8 odorantes para la detección, memoria/reconocimiento e identificación. Además, se hizo una prueba de umbral de rosa (alcohol feniletílico) de 6 diluciones, escala visual analógica (EVA). Se compararon los resultados con una prueba validada Smell Diskettes Olfaction Test (SDOT), para definir puntos de corte de hiposmia y anosmia se comparó en pacientes con DO con UPSITTM. Considerando la pandemia de COVID-19, se compararon hisopos de algodón desechables con los odorantes respecto a la prueba original. Resultados: BOT-8 se tarda entre 3 y 7 minutos en realizar. En población sana, la media de detección fue del 100%, memoria 94,5% (DE=1,07) e identificación 89,6% (DE=0,86). En pacientes con DO fue de 86% (DE=32,8), 73,2% (DE=37,9) y 77,1% (DE=34,2), respectivamente. BOT-8 demostró buena fiabilidad test-retest con 96,7% de concordancia observada y una kappa cuadrática de 0,84 (p<0,001). Presentó una fuerte correlación con SDOT (r=0,673, p <0,001) en población sana y con UPSITTM en pacientes con DO (r=0,86, p<0,001). Los hisopos de algodón desechables mostraron una excelente concordancia (kappa de 0,79) en comparación con la prueba original. El punto de corte para anosmia fue ≤ 3 (AUC=0,83, Se= 0,673, Sp=0,993) y de hiposmia ≤ 6 (AUC=0,451, Se= 0,088, Sp= 0,814). Conclusiones: BOT-8 ofrece un método eficiente y rápido para ser utilizado en la práctica clínica diaria para evaluar el sentido del olfato mediante la detección, memoria, identificación y umbral (AU)

Residual olfactory dysfunction in coronavirus disease 2019 patients after long term recovery.

INTRODUCTION: Hyposmia is among the most common symptoms of COVID-19 patients. Previous research has mainly described this issue at the disease's early stages. Because olfactory impairment can indicate neurological degeneration, we investigated the possibility of permanent olfactory damage by assessing hyposmia during the late recovery stage of COVID-19 patients. METHODS: Ninety-five patients were assessed with the Brief Smell Identification Test for Chinese (B-SITC) and Hyposmia Rating Scale (HRS) after 16 weeks from disease onset. Five weeks later, 41 patients were retested with B-SITC. RESULTS: At the first visit, hyposmia was identified in 26/82 (31.7%) and 22/95 (23.2%) of participants by HRS (HRS score ≤22) and B-SITC (B-SITC score <8), respectively. The rates of hyposmia in patients who performed B-SITC after 14-15 weeks, 16-17 weeks, and ≥18 weeks from disease onset were 7/25 (28%), 8/35 (23%) and 7/35 (20%), respectively, which demonstrated a trend of olfaction improvement as recovery time prolonging. Hyposmia percentages decreased from the first visit (34.1%) to the second visit (24.4%) for the 41 patients who completed 2 visits. B-SITC scores of the first-visit hyposmia participants increased significantly at the second visit (5.29 ± 2.02 to 8.29 ± 2.40; n = 14, P = 0.001). Severe cases tended to recover less than common cases. CONCLUSIONS: Hyposmia was present in up to one-third of COVID-19 patients after about 3 months from disease onset. Notable recovery of olfactory function was observed at a next 5-weeks follow-up. Clinical severity had little influence on olfactory impairment and recovery.

Diagnosis of Anosmia and Hyposmia: A Systematic Review.

BACKGROUND: Anosmia and hyposmia have many etiologies, including trauma, chronic sinusitis, neoplasms, and respiratory viral infections such as rhinovirus and SARS-CoV-2. We aimed to systematically review the literature on the diagnostic evaluation of anosmia/hyposmia. METHODS: PubMed, EMBASE, and Cochrane databases were searched for articles published since January 1990 using terms combined with Medical Subject Headings (MeSH). We included articles evaluating diagnostic modalities for anosmia, written in the English language, used original data, and had two or more patients. RESULTS: A total of 2065 unique titles were returned upon the initial search. Of these, 226 abstracts were examined, yielding 27 full-text articles meeting inclusion criteria (Level of evidence ranging from 1 to 4; most level 2). The studies included a total of 13,577 patients. The most utilized diagnostic tools were orthonasal smell tests (such as the Sniffin' Sticks and the UPSIT, along with validated abridged smell tests). Though various imaging modalities (including MRI and CT) were frequently mentioned in the workup of olfactory dysfunction, routine imaging was not used to primarily diagnose smell loss. CONCLUSION: The literature includes several studies on validity and reliability for various smell tests in diagnosing anosmia. Along with a thorough history and physical, validated orthonasal smell tests should be part of the workup of the patient with suspected olfactory dysfunction. The most widely studied modality was MRI, but criteria for the timing and sequence of imaging modalities was heterogenous.