Questionnaire Of Olfactory Disorders Research Articles

Determining the minimal clinically important difference for the questionnaire of olfactory disorders in people with cystic fibrosis and factors associated with improvement after highly effective modulator therapy.

Olfactory dysfunction (OD) is common among people with cystic fibrosis (PwCF). The Questionnaire of Olfactory Disorders (QOD) is a validated instrument that evaluates olfactory-specific quality-of-life. The QOD minimal clinically important difference (MCID) and factors associated with olfactory improvement after elexacaftor/tezacaftor/ivacaftor have not been determined for PwCF. Prospective observational data were pooled from three studies that enrolled adult PwCF with chronic rhinosinusitis (CRS). QOD scores and disease characteristics were assessed. To evaluate internal consistency and calculate the QOD MCID, Cronbach's alpha and four distribution-based methods were employed. For participants who enrolled prior to elexacaftor/tezacaftor/ivacaftor, QOD scores were obtained at baseline and after elexacaftor/tezacaftor/ivacaftor initiation. Multivariable regression was used to identify factors associated with QOD improvement. Of 129 PwCF included, 65 had QOD scores before and 3-6 months after starting elexacaftor/tezacaftor/ivacaftor. Mean baseline QOD score was 6.5±7.9. Mean Cronbach's alpha was ≥0.85. The MCID estimates were as follows: Cohen's effect size=1.6, standard error of measurement=2.5, ½ baseline standard deviation=4.0, and minimal detectable change=6.9. Mean MCID was 3.7. Of those with pre/post elexacaftor/tezacaftor/ivacaftor QOD scores, the mean change in QOD was -1.3±5.4. After elexacaftor/tezacaftor/ivacaftor, QOD improvement surpassed the MCID in 22% of participants (14/65). Worse baseline QOD scores and nasal polyps were associated with improved QOD scores after elexacaftor/tezacaftor/ivacaftor (both p<0.04). The QOD MCID in PwCF was estimated to be 3.7. Elexacaftor/tezacaftor/ivacaftor led to qualitative but not clinically meaningful improvements in QOD score for most PwCF; PwCF with worse baseline QOD scores and nasal polyps improved in a clinically significant manner.

Olfactory loss in people with cystic fibrosis: Community perceptions and impact.

Olfactory dysfunction (OD) is prevalent in people with cystic fibrosis (PwCF) and can negatively impact quality-of-life (QOL). This study evaluated perceptions of OD, investigated how OD impacts QOL, and assessed willingness to participate in OD research among the CF community. A 21-question survey was distributed through the CF Foundation's Community Voice program in 2023. The survey included questions on olfaction and interest in research. The Brief Questionnaire of Olfactory Disorders (BQOD), a validated person-reported outcome measure to assess QOL, was included. Seventy-six responses were received. Overall, 91% (69/76) reported olfactory problems. Mean BQOD score was 5.0 (standard deviation=4.8), indicating olfactory QOL impairment was present. Ninety-five percent (72/76) reported research on OD is worthwhile and were willing to participate in research. Among PwCF, OD and olfactory-specific QOL impairments are prevalent. There is strong interest and willingness to participate in OD research among the CF community.

Olfaction-associated quality of life: Polish adaptation and validation of a Questionnaire of Olfactory Disorders (QOD-PL) in patients with chronic rhinosinusitis.

The focus on health-related quality of life (HRQOL) in medical research is becoming more and more intensive, with attention being paid to the patient's subjective feelings and assessment of one's health status. Smell disorders can significantly impact human life. The Questionnaire of Olfactory Disorders (QOD) is a self-monitoring questionnaire that provides subjective information about olfactory disorders. This study aimed to check the reliability and validation of the Polish version of QOD (QOD-PL) for use in patients with olfactory impairment in Poland. A total of 158 patients (76 females, mean age (Mage) 45.97 ±16.37 years), suffering from chronic rhinosinusitis (CRS), whose olfactory function was measured using the Sniffin' Sticks test (SST), were studied. All patients completed 3 validated questionnaires: Importance of Olfaction (IO), Sino-Nasal Outcome Test-22 (SNOT-22) and QOD-PL. Internal consistency and test-retest reliability of the entire QOD-PL scale were good (Cronbach's α = 0.88). The convergent validity of the QOD-PL and its subscales correlated with IO and SNOT-22. The life quality statements in the QOD-PL (QOD-PL-LQ) score, its negative statements, and the mean score for VAS scales were significantly and positively correlated with all symptoms measured with SNOT-22 and none of the IO scales. The QOD-PL is a reliable, valid and important tool for assessing HRQOL in patients with olfactory disorders. However, it is important to note that not all of its subscales can be considered and interpreted separately.

Detection of disorders of the chemical senses-assessment of state of health by those affected

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 agood 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.

Italian version of the Brief Questionnaire of Olfactory Disorders (Brief-IT-QOD).

To evaluate the reliability and validity of the Italian version of the Brief Questionnaire of Olfactory Disorders (Brief-IT-QOD). The study consisted of six phases: item generation, reliability analysis (112 dysosmic patients for internal consistency analysis and 61 for test-retest reliability analysis), normative data generation (303 normosmic subjects), validity analysis (comparison of Brief-IT-QOD scores of healthy and dysosmic subjects and scores correlation with psychophysical olfactory testing TDI and SNOT-22 scores), responsiveness analysis (10 dysosmic chronic rhinosinusitis with nasal polyps patients before and after biologic therapy), and cut-off value determination (ROC curve analysis of Brief-IT-QOD sensitivity and specificity). All subjects completed the Brief-IT-QOD. Internal consistency (α > 0.70) and test-retest reliability (ICC > 0.7) were acceptable and satisfactory for both questionnaire subscales. A significant difference between dysosmic and control subjects was found in both subscales (p < 0.05). Significant correlations between subscales scores and TDI and SNOT-22 scores were observed. Brief-IT-QOD scores before treatment were significantly higher than after biological therapy. Brief-IT-QOD is reliable, valid, responsive to changes in QoL, and recommended for clinical practice and outcome research.

Reliability and validity of the Polish version of the Questionnaire of Olfactory Disorders.

The comprehensive counseling of patients with olfactory dysfunctions requires accurate diagnosis. The recommendations include subjective assessment. The Questionnaire of Olfactory Disorders (QOD) is a disease-specific questionnaire for the subjective evaluation of olfactory dysfunctions. The study included 54 patients with olfactory dysfunctions, who were recruited to the study group (SG). The other 47 patients without the history of olfactory dysfunction and nasal cavity pathology were voluntarily allocated to the control group (CG). The protocol of the study was introduced to each patient and included: olfactory testing with Sniffin' Stick test, fulfillment of the Polish version of World Health Organization Quality of Life brief questionnaire and completing of the Polish version of the QOD. All participants (101) were invited for refilling the QOD questionnaire after 2 weeks for the test-retest statistics. The Polish QOD statements were significantly correlated and met the requirement by having test-retest correlation larger than 0.7. We found that internal consistency of the test measured by Cronbach's alpha coefficient was very high. The mean scores of the QOD test in normosmic SG patients were compared with corresponding scores in normosmic CG patients using U Mann-Whitney test. The analysis revealed statistically significant differences on mean QOD scores for each domains except QOD-S between both groups. The Polish version of the QOD demonstrated high rate of the validity and the reliability. This instrument may be widely used in research projects and clinical practice concerning olfactory disorders in Polish patients. NA.

Comparison between olfactory training and curcumin therapy in improving olfactory dysfunction in patients with chronic kidney disease

ObjectiveOlfactory dysfunction can be seen in chronic kidney disease (CKD) patients. We aimed to investigate the effects of olfactory training and curcumin on olfactory dysfunction in CKD patients and compare their impact with a placebo. MethodsWe conducted a double-blind, randomized, placebo-controlled trial in CKD patients, 2021–2022. We enrolled 60 participants in our study into three groups (curcumin, training, and control). Participants were randomized into trials and control groups and assessed using the Iran-smell identification test (Iran-SIT), a questionnaire of olfactory disorders (QOD), and a self-assessment tool. P-value < 0.05 was considered statistically significant. ResultsWe gathered 58 participants (mean age of 56.1 ± 2.5, 56.9% men). All the tests showed that curcumin improved olfactory function after the trial, though it was significant in QOD (17.5 ± 11.8 vs. 13.1 ± 9.7, p = 0.045) and self-assessment results (8.5 ± 3.1 vs. 9.5 ± 4.0, p = 0.047). Moreover, compared to baseline, training patients experienced an increase in their olfactory function in Iran-SIT (15.3 ± 4.9 vs. 18.8 ± 2.7, p = 0.001), QOD (19.0 ± 10.4 vs. 12.2 ± 9.9, p = 0.003), and self-assessment tools (6.8 ± 1.8 vs. 8.2 ± 3.1, p = 0.027). In contrast, the olfactory function was unchanged in control in all the tests (p > 0.05). Also, the improved change of Iran-SIT and QOD scores during the trial was more significant in training compared to the curcumin group (p < 0.002). ConclusionThe findings of this study indicate that olfactory training, even more than curcumin, can improve olfactory function in CKD patients. This information may help manage olfactory dysfunction in the CKD population.

The Correlation between the Results of the Sniffin' Sticks Test, Demographic Data, and Questionnaire of Olfactory Disorders in a Hungarian Population after a SARS-CoV-2 Infection.

After a severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, smell disorders frequently occur, significantly affecting patients' quality of life (QoL). 110 patients with persistent olfactory disorder after coronavirus infection were enrolled. These patients underwent chemosensory testing using the Sniffin' Sticks test, and completed the Questionnaire of Olfactory Disorders (QOD). 30% of the patients reported anosmia, and 70% reported hyposmia. Upon comparing subjective and chemosensory testing categories, good category matching was observed in 75.3% (i.e., anosmia based on both methods in 10 and hyposmia in 48 cases). Statistical analysis using the Chi-square test revealed a significant result (p = 0.001 *). Between the TDI (i.e., Threshold, Discrimination, Identification) results of the three subjective report groups (i.e., hyposmia, anosmia, and parosmia), no significant differences were observed. When the TDI and QOD results were compared, no consistent significant correlations were found in most TDI and QOD outcomes. Between the TDI and Scale 2 results, a significant, although slight correlation was observed by the Spearman's (rho = 0.213, p = 0.027 *) and Pearson's (rho = 0.201, p = 0.037 *) tests. The nonsignificant correlation between objective and subjective methods suggests that these results should be interpreted independently. Moreover, adequate management is essential even in mild cases.

Impact of COVID-19 versus chronic rhinosinusitis/rhinitis associated olfactory dysfunction on health utility and quality of life.

BackgroundOlfactory dysfunction (OD) is associated with both post‐viral and inflammatory etiologies such as COVID‐19 and chronic rhinosinusitis/rhinitis (CRS/R) respectively, to result in reduced quality of life (QoL). However, the former typically induces a sudden‐onset OD while the latter has a gradual presentation. This study aims to establish and compare health utility values (HUVs) and olfactory‐specific QoL measurements between patients with COVID‐19 and CRS/R related OD.MethodsThis prospective study surveyed COVID‐19 and CRS/R patients with self‐reported OD using HUV assessments (EuroQol‐visual analog scale [EQ‐VAS], EuroQol‐5 dimension [EQ‐5D], time trade‐off [TTO]) and olfactory and sinonasal QoL measures (questionnaire of olfactory disorders –negative and positive statements [QOD‐NS + PS] and sino‐nasal outcome test [SNOT‐22]). A subgroup of subjects completed objective olfactory testing. Intergroup mean scores were compared using Mann–Whitney U tests.ResultsOne hundred eleven subjects were enrolled: mean age ± SD (43.0 ± 15.4 years), 55.9% female. CRS/R was associated with lower HUVs as measured by EQ‐VAS (CRS/R: 0.67 ± 0.18 vs. COVID‐19: 0.74 ± 0.19, p = .03) and worse SNOT‐22 scores in both overall (CRS/R: 49.03 ± 21.04 vs. COVID‐19: 27.58 ± 18.45, p < .001) and subgroup analysis of objectively confirmed OD subjects (CRS/R: 52.40 ± 22.78 vs. COVID‐19: 29.84 ± 21.10, p = .01). On the other hand, COVID‐19 has greater burden on olfactory‐specific QoL (QOD‐NS + PS, COVID‐19: 23.19 ± 13.73 vs. CRS/R: 17.25 ± 11.38, p = .04). Both groups demonstrated a similar decrease in health using the EQ‐5D assessment.ConclusionCRS/R associated OD has a more severe impact on general health and sinonasal specific QoL outcomes, while COVID‐19 associated OD has a greater burden on olfactory‐specific QoL.Level of evidenceLevel 2c.

Impact of COVID-19-Mediated Olfactory Loss on Quality of Life

Introduction: COVID-19 can be associated with a variety of longer-lasting impairments that can have a significant impact on patients’ quality of life (QoL). While this is well described in the literature for limitations in lung capacity or permanent headaches, there is little research on the impact of olfactory dysfunction in the context of COVID-19 on patients’ QoL. Methods: In 65 patients with a history of COVID-19, the present olfactory ability was assessed using the Sniffin’ Sticks test. In addition, olfactory QoL was assessed by the Questionnaire of Olfactory Disorders. Self-assessment was performed with visual analogue scales. The data were compared with the results obtained in healthy individuals and in patients with hyposmia due to other viral infections. Results: The QoL of COVID-19 patients was significantly lower compared to the healthy control group. Even recovered subjects whose olfaction had already returned to the normal range still had a reduced QoL. The severity of the olfactory impairment correlated with the reduction in QoL. However, the olfactory QoL of COVID-19 patients was not worse than that of patients’ olfactory loss due to other viral infections. Patients with parosmia had reduced QoL and rated their situation worse than patients without parosmia. Conclusion: QoL appears to be impaired in patients with long-lasting COVID-19 olfactory disorders several months after overcoming acute symptoms, even if olfaction has normalized. However, the impairment is not more pronounced than in patients with other postviral olfactory disorders of the same duration.

Olfactory dysfunction in cystic fibrosis: Impact of CFTR modulator therapy

BackgroundElexacaftor-tezacaftor-ivacaftor (ETI) improves pulmonary health and chronic rhinosinusitis (CRS) for people with cystic fibrosis (PwCF), however its impact on olfaction has not been investigated. Olfactory dysfunction impairs quality-of-life (QOL). This study evaluated the impact of ETI on multiple olfactory metrics. MethodsAdult PwCF/CRS with CF transmembrane conductance regulator genotype F508del/F508del or F508del/minimal function who clinically initiated ETI participated in a prospective, observational study. Endpoints included changes after 6 months of ETI in quantitative olfactory function (Smell Identification Test, SIT), olfactory QOL (Questionnaire of Olfactory Disorders, QOD) and percent olfactory cleft opacification (%OCO), representing superior nasal cavity inflammation where afferent olfactory neurons are concentrated. Results30 PwCF/CRS met inclusion criteria; 25 completed the study. Mean ETI adherence was 93%. At baseline, participants were hyposmic (mean SIT 31.3), had significant %OCO (mean 65.6%), yet reported non-impaired olfactory QOL (mean QOD 6.1). At follow-up, mean SIT worsened mildly (p=0.009), mean %OCO remained stable (p=0.46), and mean QOD improved modestly (p=0.008). No outcomes were impacted by prior modulator use, genotype, nasal polyps, or CF-related diabetes. Prior sinus surgery was associated with QOD improvement (p=0.04). Increased (worse) baseline QOD scores and %OCO were associated with greater improvements (p<0.003), but not SIT (p=0.44). ConclusionsETI was not associated with improvement in quantitative olfaction or olfactory cleft opacification after 6 months. PwCF/CRS have hyposmia but do not report impairment in olfactory QOL. Further study to investigate mechanisms explaining olfactory dysfunction and whether olfaction improves with greater duration of ETI or in younger age groups is warranted.

Association of Quality of Life Measures and Otolaryngologic Care in Cystic Fibrosis Patients.

Appropriate management of chronic rhinosinusitis (CRS) among patients with cystic fibrosis (CF) is important in improving quality of life. Otolaryngologists play a critical role in reducing CRS symptom burden. This study seeks to evaluate the role of patient-reported quality-of-life measures in guiding interventions for CF-related sinus disease. We performed a prospective, cross-sectional study of 105 patients presenting to a CF-accredited clinic between July and September 2018. Demographic data and sinus surgery history were collected, in addition to Sino-Nasal Outcome Test (SNOT-22) and Questionnaire of Olfactory Disorders (QOD-NS) scores. Statistical analysis was conducted using correlation and non-parametric Mann-Whitney U tests. Baseline well-care visits accounted for 71.4% of all clinical evaluations. Prior otolaryngology intervention was noted in 69 (66%) patients, where the majority of these patients (63/69; 91%) underwent endoscopic sinus surgery (ESS). Patients with a history of otolaryngology intervention had an average SNOT-22 score of 33.2 (SD = 20.6) compared to 24.9 (SD = 18.5) for patients without prior intervention (P = .048). The average QOD-NS score was 5.5 (SD = 6.4) among patients referred to otolaryngologists and 3.1 (SD = 5.7) for non-referred patients (P = .012). SNOT-22 and QOD-NS scores were modestly correlated (R of .43). CF patients with symptoms resulting in worse quality-of-life assessments were more likely to have established coordinated care with an otolaryngologist. Further validation of the utility of SNOT-22 and QOD-NS questionnaires as care coordination metrics is necessary in the CF population.

Association between olfactory function and quality of life in patients with olfactory disorders: a multicenter study in over 760 participants.

This cross-sectional, multi-centric study aimed to investigate the differences in quality of life among patients with olfactory dysfunction (OD) of different origin, and to identify factors associated with olfactory-related quality of life (QOL). Seven hundred sixty-three adults were recruited from 8 Smell & Taste clinics in Germany, Switzerland, and Austria. Olfactory-related QOL was assessed by the Questionnaire of Olfactory Disorders (QOD). Olfactory function was assessed with the "Sniffin' Sticks" test; self-assessment was performed with visual analog scales. Patients with post-infectious and post-traumatic OD showed poorer olfactory-related QOL than patients with sinonasal and idiopathic OD. The olfactory-related QOL was positively associated with the "Sniffin' Sticks" test score, self-assessed olfactory function, disease duration, and age, with younger olfactory dysfunction patients showing lower QOL. Female patients presented with poorer olfactory-related QOL. In addition, the results showed that self-assessment of olfactory function explained more of the variance in olfactory-related QOL than olfactory function evaluated by the Sniffin’ Sticks test. In addition to the psychophysical testing results, several factors such as disease cause, disease duration, sex, or self- assessed olfactory dysfunction should be taken into account when assessing the individual severity of the smell loss.

Clinical Features of Olfactory Dysfunction in COVID-19 Patients.

BackgroundThe 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.MethodsA 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.ResultsThe 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.ConclusionAlthough 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.

Self-perceived Taste and Flavor Perception: Associations With Quality of Life in Patients With Olfactory Loss.

To evaluate associations between self-perceived chemosensory functions of smell, taste, and flavor perception with olfactory-specific quality of life (QoL) in patients with olfactory dysfunction (OD) and whether these associations would be influenced by other factors, such as duration or etiology of smell loss. Retrospective cohort study. Tertiary care, academic center. Olfactory-specific QoL was measured with the Questionnaire of Olfactory Disorders (QOD). The QOD measures the impact of OD on QoL (QOD-negative statements) and the ability of patients to cope with smell loss (QOD-positive statements). Orthonasal olfactory function, patients' demographics, self-perceived chemosensory perception, and duration and etiology of OD were retrospectively collected in a cohort of patients with quantitative OD. Correlations and multivariable linear regression models were computed to determine possible associations with the outcome measure of QOD-negative and QOD-positive statement scores. A total of 133 patients with OD were included. Analysis revealed a positive correlation between self-perceived taste and flavor perception with QOD-negative statement scores, while self-perceived smell showed no significant correlation. Similarly, longer duration of smell loss and higher age were also correlated with higher QOD-positive statement scores. Multivariable regression models confirmed that self-perceived taste was independently associated with the QOD-negative statement score, while age and duration of OD were independently associated with the QOD-positive statement score. These findings suggest that the impact of diminished flavor perception during eating and drinking has a stronger impact on the QoL of patients with OD as compared with decreased orthonasal olfaction.

Essential Oil Olfactory Test: Comparison of Affordable Rapid Olfaction Measurement Array (AROMA) to Sniffin' Sticks 12.

ObjectivesTo further demonstrate the validity of Affordable Rapid Olfaction Measurement Array (AROMA), an essential oil−based smell test, and compare it to the Sniffin’ Sticks 12 Test (SST12).Study DesignProspective cross-sectional study.SettingAcademic medical center.MethodsFifty healthy individuals without sinonasal disease were recruited to the study. AROMA has been previously validated against the University of Pennsylvania Smell Identification Test. The current study tests 2 additional higher concentrations to increase the ability to detect olfactory reserve. Healthy participants completed AROMA, SST12, Sino-Nasal Outcome Test (SNOT-22), and Questionnaire of Olfactory Disorders (QoD). Spearman correlations were used to evaluate AROMA, SST, SNOT-22, and QoD.ResultsAROMA demonstrated strong test-retest reliability (r = 0.757, P < .01). AROMA showed a moderate correlation to SST12 (ρ = 0.412, P < .01). Age and SNOT-22 were significantly correlated (P < .05) with AROMA (ρ = −0.547, −0.331, respectively), and age was weakly correlated with SST (ρ = −0.377, P < .01). Median percent correct scores were as follows: SST12 identification, 92%; AROMA detection, 90%; and AROMA identification, 81%. Median correct odor identification of AROMA concentrations at 1×, 2×, 4×, and 8× were 64%, 75%, 92%, and 92%, respectively.ConclusionAROMA has a moderate correlation with SST12. AROMA is more strongly correlated than SST12 to age and SNOT-22. AROMA’s stronger correlation with subjective olfactory status, low cost, and adaptability may help remove barriers to routine olfactory testing in the clinic.

Olfactory and Gustatory Dysfunction as an Early Identifier of COVID-19 in Adults and Children: An International Multicenter Study.

ObjectiveTo evaluate the prevalence and characteristics of olfactory or gustatory dysfunction in coronavirus disease 2019 (COVID-19) patients.Study DesignMulticenter case series.SettingFive tertiary care hospitals (3 in China, 1 in France, 1 in Germany).Subjects and MethodsIn total, 394 polymerase chain reaction (PCR)–confirmed COVID-19-positive patients were screened, and those with olfactory or gustatory dysfunction were included. Data including demographics, COVID-19 severity, patient outcome, and the incidence and degree of olfactory and/or gustatory dysfunction were collected and analyzed. The Questionnaire of Olfactory Disorders (QOD) and visual analog scale (VAS) were used to quantify olfactory and gustatory dysfunction, respectively. All subjects at 1 hospital (Shanghai) without subjective olfactory complaints underwent objective testing.ResultsOf 394 screened subjects, 161 (41%) reported olfactory and/or gustatory dysfunction and were included. Incidence of olfactory and/or gustatory disorders in Chinese (n = 239), German (n = 39), and French (n = 116) cohorts was 32%, 69%, and 49%, respectively. The median age of included subjects was 39 years, 92 of 161 (57%) were male, and 10 of 161 (6%) were children. Of included subjects, 10% had only olfactory or gustatory symptoms, and 19% had olfactory and/or gustatory complaints prior to any other COVID-19 symptom. Of subjects with objective olfactory testing, 10 of 90 demonstrated abnormal chemosensory function despite reporting normal subjective olfaction. Forty-three percent (44/102) of subjects with follow-up showed symptomatic improvement in olfaction or gustation.ConclusionsOlfactory and/or gustatory disorders may represent early or isolated symptoms of severe acute respiratory syndrome coronavirus 2 infection. They may serve as a useful additional screening criterion, particularly for the identification of patients in the early stages of infection.

Reliability and validity of the Turkish version of the questionnaire of olfactory disorders

Reliability and validity of the Turkish version of the questionnaire of olfactory disorders

Trend of Olfactory and Gustatory Dysfunction in COVID-19 Patients in a Quarantine Facility.

BackgroundOlfactory and gustatory dysfunction has been reported as characteristic symptoms of coronavirus disease 2019 (COVID-19). This study evaluated olfactory and gustatory dysfunction in mild COVID-19 patients using validated assessment methods.MethodsA prospective surveillance study was conducted for mild COVID-19 patients who were isolated at the Gyeonggi International Living and Treatment Support Center (LTSC), Korea. Olfactory function was assessed using the Korean version of the Questionnaire of Olfactory Disorders (QOD) and Cross-Cultural Smell Identification Test (CC-SIT). Gustatory function was assessed using an 11-point Likert scale and 6-n-propylthiouracil, phenylthiocarbamide, and control strips. All patients underwent nasal and oral cavity endoscopic examination.ResultsOf the 62 patients at the LTSC, 15 patients (24.2%) complained of olfactory or gustatory dysfunction on admission. Four of 10 patients who underwent functional evaluation did not have general symptoms and 2 were asymptomatic. The mean short version of QOD-negative statements and QOD-visual analogue scale scores were 13 ± 6 and 4.7 ± 3.6, respectively. The mean CC-SIT score was 8 ± 2. No patients showed anatomical abnormalities associated with olfactory dysfunction on endoscopic examination. The mean Likert scale score for function was 8 ± 2, and there were no abnormal lesions in the oral cavity of any patient.ConclusionsThe prevalence of olfactory and gustatory dysfunction was 24.2% in mild COVID-19 patients. All patients had hyposmia due to sensorineural olfactory dysfunction, which was confirmed using validated olfactory and gustatory evaluation methods and endoscopic examination. Olfactory and gustatory dysfunction may be characteristic indicators of mild COVID-19.

Olfactory and Gustatory Dysfunction in Mild COVID-19

Background: Olfactory and gustatory dysfunction have been reported as characteristic symptoms of coronavirus disease 2019 (COVID-19). This study evaluated olfactory and gustatory dysfunction in mild COVID-19 patients using validated assessment methods. Methods: A prospective surveillance study was conducted for mild COVID-19 patients who were isolated at the Gyeonggi International Living and Treatment Support Center (LTSC), Korea. Olfactory function was assessed using the Korean version of the Questionnaire of Olfactory Disorders (QOD) and Cross-Cultural Smell Identification Test (CC-SIT). Gustatory function was assessed using an 11-point Likert scale and 6-n-propylthiouracil, phenylthiocarbamide, and control strips. All patients underwent nasal and oral cavity endoscopic examination. Findings: Of the 62 patients at the LTSC, 15 patients (24.2%) complained of olfactory or gustatory deterioration on admission. Four of 10 patients who underwent functional evaluation did not have general symptoms and 2 patients were asymptomatic. The mean sQOD-NS and QOD-VAS scores were 13 ± 6 and 4.7 ± 3.6, respectively. The mean CC-SIT score was 8 ± 2. No patients showed anatomical abnormalities associated with olfactory dysfunction on endoscopic examination. The mean Likert scale score for function was 8 ± 2, and there were no abnormal lesions in the oral cavity of any patient. Interpretation: The prevalence of olfactory and gustatory dysfunction was 24.2% in mild COVID-19 patients. All patients had hyposmia due to sensorineural olfactory deterioration, which was confirmed using validated olfactory and gustatory evaluation methods and endoscopic examination. Olfactory and gustatory dysfunction may be characteristic indicators of mild COVID-19. Funding Statement: No funding. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: This study protocol was approved by the Institutional Review Board of the Korea University Ansan Hospital (2020AS0122).