A brief version of the questionnaire of olfactory disorders in patients with chronic rhinosinusitis

Reliability and validity of the Arabic version of the brief version of the Questionnaire of Olfactory Disorders

Background

An accessible self-assessment questionnaire is needed to evaluate quality of life in olfactory dysfunction. The need to address this gap led to the development of the brief version of the Questionnaire of Olfactory Disorders (brief QOD), which holds particular value in the context of telemedicine.

Objectives

The aim of this study is to examine the reliability and validity of the Arabic brief QOD.

Methods

This study included 307 patients suffering from olfactory dysfunction as well as a control group filled a questionnaire including demographic information, the olfaction Visual Analog Scale (VAS), the Sino-nasal Outcome Test 22 (SNOT-22) questionnaire, and the Arabic version of the brief QOD. The Arabic brief QOD's reliability was assessed using Cronbach's α to measure internal consistency. To evaluate test-retest reliability, the intraclass correlation coefficient (ICC) was employed. The discriminative ability: score differences between the two groups were analyzed. The validity Arabic brief QOD was evaluated by comparing it to the olfaction VAS.

Results

The Cronbach's α coefficients were 0.757 for Questionnaire of Olfactory Disorders-Parosmia (QOD-P), 0.832 Questionnaire of Olfactory Disorders-quality of life (QOD-QoL), and 0.817 Questionnaire of Olfactory Disorders-visual analog scale (QOD-VAS). The reliability of the overall brief QOD was 0.93. The ICC exceeded the acceptable threshold of 0.7, indicating strong test-retest reliability. The highest correlation was observed between the SNOT-22 and QOD total scores (r = 0.552 and p < .001) as well as between SNOT-22 and QOD VAS (r = 0.512 and p < .001).

Conclusion

Excellent validity and reliability have been shown for the Arabic brief QOD as a self-assessment tool assessing quality of life among olfactory dysfunction patients.

Level of evidence

NA.

The olfactory diary: Tracking awareness and consciousness of the sense of smell throughout the day

Objectives

The aim of the present study was to follow the daily course of patients with olfactory dysfunction and healthy controls and to assess (i) how many times a day, (ii) at which time, and (iii) in which aspect of daily life participants are conscious about their sense of smell.

Methods

In this longitudinal study, 49 patients with smell loss and 30 healthy participants were enrolled. Olfactory function was assessed using the Sniffin' Sticks. All participants received paper diaries designed for a 14-day period, featuring 12 rows representing 12 daily hours and six columns for various daily life aspects. They were instructed to mark their awareness of smell by indicating the relevant row and column in the diary. Following the return of the diaries, a second olfactory test was conducted within the patient group.

Results

On average, patients were consciously aware of their sense of smell around 8 times daily, while healthy participants noted it about 6.5 times a day. Both groups primarily focused on their sense of smell during activities related to "eating," followed by considerations in "social life" and "personal hygiene." Interestingly, distinct patterns emerged: patients peaked in awareness at 8 a.m. and 7 p.m., whereas healthy individuals showed peaks at 6 a.m., 12 p.m., and 7 p.m. Despite regular diary use, we observed no improvement in patients' olfactory function or related quality of life.

Conclusion

The olfactory diary is a valuable tool unveiling individual smell awareness patterns in patients with smell loss, aiding in counseling and patient management.

Level of Evidence

4.

Validation and reliability of the Italian version of the Self-reported Mini Olfactory Questionnaire (Self-MOQ)

Objective

Olfactory dysfunction (OD) represents a frequent complaint in general population and especially in patients with chronic sinonasal diseases. The aim of this study was the cross-cultural adaptation and validation of the Self-reported Mini Olfactory Questionnaire (Self-MOQ) into Italian.

Methods

One hundred fifty patients affected by chronic sinonasal diseases and reporting hyposmia were enrolled. Other 150 normosmic subjects without inflammatory or neoplastic sinonasal disorders were used as a control group. The Short-form 36 (SF-36) questionnaire was used for clinical validity.

Results

Cronbach's alpha coefficient was 0.825. The test-retest reliability was excellent. The good correlation between the Self-MOQ and the Visual Analogue Scale scores (p < 0.05) demonstrated the construct validity of the questionnaire. The Self-MOQ was able to distinguish between subjects with or without OD (p < 0.05). Higher Self-MOQ score was found in case of nasal obstruction and posterior rhinorrhoea (p < 0.05). Self-MOQ showed significant correlation with SF-36 general health, SF-36 role functioning/physical, and SF-36 pain (p < 0.05).

Conclusions

The Italian version of the Self-MOQ showed good internal consistency, test-retest reliability, construct, and clinical validity.

Impact of post-COVID-19 olfactory disorders on quality of life, hedonic experiences and psychiatric dimensions in general population

BACKGROUND AND OBJECTIVE

Olfactory disorders in COVID-19 impact quality of life and may lead to psychological impairments. Prevalence ranges from 8 to 85%, persisting in about 30% of cases. This study aimed to evaluate the 6-month post-COVID-19 impact on quality of life, hedonic experiences, anxiety and depression due to olfactory disorders. Additionally, it sought to compare psychophysical tests and self-perceived olfactory evaluations.

METHODS

A prospective, longitudinal study was conducted over baseline (T0) and 6 months (T1) on individuals with persistent olfactory disorders post-COVID-19 for more than 6 weeks. Psychophysical tests employed the Sniffin' Sticks Test® (TDI score), and self-perceived olfactory evaluation used a Visual Analogue Scale. Quality of life was assessed with an Olfactive Disorder Questionnaire and the French version of the Quality of Life and Diet Questionnaire. Hedonic experiences were gauged using the Snaith-Hamilton Pleasure Scale, while anxiety and depression dimensions were measured by The State-Trait Anxiety Inventory, The Post Traumatic Stress Checklist Scale, and Hamilton Rating Scale for Depression. Participants were classified into the "normosmic group" (NG) and the "olfactory disorders group" (ODG) at T0 and T1 based on the TDI score.

RESULTS

Were included 56 participants (58.93% women, 41.07% men) with a mean age of 39.04 years and a mean duration of post-COVID-19 olfactory disorders of 5.32 months. At T1, ODG had a significantly lower quality of life and hedonic experiences than NG. No significant differences in anxiety and depression dimensions were observed between groups. At T0, psychophysical tests and self-perceived olfactory evaluations were significantly correlated with quality of life and hedonic experiences in both groups. At T1, self-perceived olfactory evaluation in NG correlated significantly with quality of life, hedonic experiences, anxiety and depression dimensions, whereas ODG only correlated with hedonic experiences.

CONCLUSION

Individuals with persistent post-COVID-19 olfactory disorders after six months demonstrated compromised quality of life and hedonic experiences. Self-perceived olfactory evaluation played a more significant role in influencing quality of life and the dimension of anxiety and depression than the psychophysical presence of olfactory disorders. These findings emphasize the importance of considering patients' perceptions to comprehensively assess the impact of olfactory disorders on their well-being.

TRIAL REGISTRATION

ClinicalTrials.gov number (ID: NCT04799977).

Validity and Reliability of the French Short Version of the Questionnaire of Olfactory Disorders-Negative Statements (sQOD-NS)

OBJECTIVE

To develop a French Short Version of the Questionnaire of Olfactory Disorders-Negative Statements (Fr-sQOD) to assess the quality of life impairments of patients with olfactory dysfunction (OD).

METHODS

Patients with OD and controls were enrolled from 2 academic centers. Individuals completed the Fr-sQOD, an OD visual analog scale severity, and the French version of the sinonasal outcome tool-22 (SNOT-22). Cronbach α was used to measure the internal consistency of Fr-sQOD. The reliability and the external validity of Fr-sQOD were assessed through a test-retest approach and by correlating Fr-sQOD with SNOT-22 scores, respectively. The external validity was assessed by correlation analysis between Fr-sQOD and the result of an assessment of the severity of OD on a visual analog scale.

RESULTS

Eighty patients completed the evaluations. The internal consistency was adequate (Cronbach α .96), and the test-retest reliability was high in the entire cohort (rs = 0.877, P < .001). The correlation between Fr-sQOD total scores and the severity of OD was moderate but significant (rs = -0.431; P = .001) supporting an acceptable external validity. Patients with OD had a significantly higher score of Fr-sQOD than healthy individuals (P < .001), indicating a high internal validity.

CONCLUSION

The Fr-sQOD is a reliable and valid self-administered tool in the evaluation of the impact of OD on quality of life of French-speaking patients.

Validation of a questionnaire assessing smell loss in an international aspirin-exacerbated respiratory disease population

Background: Olfactory dysfunction (OD) and smell loss affects aspects of patients' everyday life and lowers their quality of life. OD questionnaires are considered one of the core-outcome measures in chronic rhinosinusitis, but many existing smell loss questionnaires contained pandemic-prohibitive questions on social gatherings or restaurant visits, were too culture specific or gender specific, or were overly long and cumbersome. Objective: We aimed to develop a new brief questionnaire to assess the impact and consequences of smell loss and its burden on daily life. This study validates this new, short, multicultural, dichotomized questionnaire in an international population that has aspirin-exacerbated disease (AERD). Methods: The Consequences of Smell Loss (COSL) questionnaire was developed and content validity was assessed by experts and patients at Brigham and Women's Hospital. The questionnaire, along with other validated quality-of-life surveys, was answered by 853 patients with AERD. We evaluated the factor structure, reliability, validity, and discriminative ability of the COSL questionnaire. Results: The final version of the COSL questionnaire consisted of 13 items divided into three subdomains (emotional distress, food and safety, and physical health) through factor analysis. The Cronbach α for internal consistency was 0.82. Convergent and discriminant validity with the 22-item Sinonasal Outcome Test (SNOT-22), Healthy Days Core Module-4, Patient Health Questionnaire-4, and a specific question on taste and smell were high (p < 0.0001 for all). The COSL questionnaire score was associated with SNOT-22 categories (p < 0.001) and was categorized as follows: normal, 0-1 points; very few consequences, 2-3 points; few, 4 points; moderate, 5-6 points; and severe, 7-13 points. Conclusion: The COSL questionnaire is a new, brief, valid, reliable tool that can effectively screen for a high burden of OD in patients with AERD and has the potential to be used in other patient populations with OD as well.

Validation and cross-cultural adaptation of the Arabic version of the self-reported mini olfactory questionnaire (Self-MOQ)

Background

A simple self-assessment screening questionnaire for olfactory dysfunction is direly needed in Rhinology practice, and this questionnaire should be accessible to affected individuals. The self-reported mini olfactory questionnaire (Self-MOQ), constructed to fill this gap, could be an important tool, especially in the era of telemedicine.

Objectives

The aim of this study was to assess the validity and reliability of the Arabic version of the self-reported mini olfactory questionnaire (Self-MOQ) in patients with olfactory dysfunction.

Methodology

This cross-sectional study included all adult patients who visited a rhinology clinic between January and June 2023 with a complaint of olfactory dysfunction and a control group. The participants completed a questionnaire that included items on demographics, risk factors of olfactory dysfunction, the olfaction VAS, SNOT-22, and Arabic Self-MOQ. The Self-MOQ was forward- and back-translated by qualified professional translators familiar with American English and Arabic.The reliability of the Arabic Self-MOQ was evaluated using Cronbach's α. The test-retest reliability was assessed by estimating the intraclass correlation coefficient (ICC) for the total Arabic Self-MOQ score and the individual items. The discriminative ability was examined by comparing the scores of the case and control groups. The construct validity was assessed by comparing the Arabic Self-MOQ to the olfaction VAS.

Results

The study sample included 307 respondents (196 cases and 111 controls; 34 undertook the retest). The Cronbach's α coefficients were 0.92 (total Self-MOQ) and considered excellent. The ICC for the total Self-MOQ score was 0.87 (95% CI: 0.757, 0.933; p < .001), which indicated good test-retest reliability. Strong correlations were observed between the Self-MOQ items and VAS scores (r = 0.732, p < .001), (r = 0.689, p < .001).

Conclusion

The current investigation showed the Arabic version of the Self-MOQ to be a reliable tool for olfactory dysfunction screening.

Clinical factors influencing olfactory performance in patients with persistent COVID-19 smell loss longer than 1 year

Objectives

Factors affecting persistence of COVID-19-related olfactory dysfunction (OD) remain partially unknown. We aim to evaluate the clinical factors which could influence olfactory performance in patients with persistent COVID-19-related smell loss.

Methods

A retrospective analysis of 100 patients with persistent COVID-19-related OD was performed between October 2020 and December 2022 at a single-center long-COVID smell clinic. All subjects underwent smell assessment using Sniffin' Sticks (S'S) extended test, nasal endoscopy, nasal airflow evaluation (peak nasal inspiratory flow [PNIF]), allergy test (skin prick test [SPT]) for common aeroallergens, MRI of the head and patient-reported outcome measures (PROMs-VAS, SF-36, Short QOD-NS, SNOT-22). Based on S'S score, subjects were divided into normosmics (TDI ≥ 30.75) and dysosmics (TDI < 30.75).

Results

The median age was 42 years and the median length of patient-reported OD was 1.4 years. 20 patients (20.0%) were normosmic at the time of S'S assessment. Dysosmic patients were found to have significantly lower scores at the SF-36 health domains for energy/fatigue (p = .0004) and emotional wellbeing (p = .04) when compared to normosmics. A moderate correlation (r = .45-.59) between S'S scores and some PROMs was also demonstrated. At the multivariate analysis higher PNIF scores positively influenced odor threshold (p = .001) while positivity to SPT negatively influenced odor identification (p = .04).

Conclusions

Impairment of nasal airflow and sensitivity to aeroallergens can negatively affect olfactory performance in COVID-19-related OD. Long-COVID smell loss deeply affects QoL although recovery of olfaction can bring it back to a normal range.

Level of Evidence

IV.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

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

Background

Olfactory and gustatory dysfunctions are frequently reported symptoms among COVID-19 patients. However, several reports suggested that there might be significant variation in the prevalence and clinical picture of chemosensory dysfunction in COVID-19 patients among different population.

Objective

To study the prevalence of chemosensory dysfunction, recovery time and its impact on quality of life (QoL) among COVID-19 patients in Saudi population.

Methods

This multi-centre observational study was conducted at three COVID-19 centres in Saudi Arabia. Epidemiological and clinical data were extracted at baseline and within the 2-month post-infection. Olfactory and gustatory dysfunctions were assessed via valid taste and smell questionnaire, electronically collected via online survey. Short version of questionnaire of Olfactory disorders-negative statements (sQOD-NS) was used to assess the impact on QoL.

Result

Total 1734 patients [926 males and 808 females, the mean age of patients was 37.7±11.6 years] with laboratory confirmed COVID-19 were recruited for this study. Chemosensory dysfunction was reported in 56.5% cases. olfactory and gustatory dysfunctions were significantly high in females (66.2%) and age group younger than or equal to 40 years (62.2%). Among patients with olfactory dysfunction and gustatory dysfunction, recovery rate was 757 (77.2%) and 702 (71.6%). Furthermore, the recovery time was within 8 days of onset of symptoms in 53.6% and 61.3% of olfactory dysfunction and gustatory dysfunction cases, respectively. Overall mean QoL score indicated Olfactory and gustatory dysfunction has significant impact on QoL [11.3±6.2 (P value<0.001)]. female as compared to males (12.8±7). Females had significant impact on QoL (11.4±6.6) as compared to males [12.8±7 (P value<0.001)].

Conclusion

Chemosensory dysfunction among Saudi population was comparable to the European data and significantly higher than Asian supporting the fact that these symptoms vary as per ethnicity. Olfactory and gustatory dysfunction significantly impaired QoL and could present as an early symptom of COVID-19. Recovery rate of these symptoms can serve as a good prognostic data for patient's counselling. Further long-term follow-up studies would lead to better understanding of prognosis and clinical outcomes.

[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 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.

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

Background

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.

Material

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.

Results

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.

Conclusions

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.

Level of Evidence

NA.

Transient Anosmia and Dysgeusia in COVID-19 Disease: A Cross Sectional Study

Objective

This study aims to explore the prevalence of anosmia and dysgeusia and their impact on COVID-19 patients.

Methods

This is a cross-sectional study. Patients diagnosed with COVID-19 between 1st October 2020 and 30th June 2021 were randomly selected from a national COVID-19 registry. COVID-19 cases were diagnosed using molecular testing method which measured the viral E gene. The Anosmia Reporting Tool, and a brief version of the questionnaire on olfactory disorders were used to measure the outcomes via telephone interviews. Data were analysed using SPSS 27 statistics software.

Results

A total of 405 COVID-19 adults were included in this study, 220 (54.3%) were males and 185 (45.8%) were females. The mean±SD age of participants was 38.2 ± 11.3 years. Alterations in the sense of smell and taste were reported by 206 (50.9%), and 195 (48.1%) of the patients, respectively. Sex and nationality of participants were significantly associated with anosmia and dysgeusia (p < 0.001) and (p-value=0.001) respectively. Among patients who experienced anosmia and dysgeusia, alterations in eating habits (64.2%), impact on mental wellbeing (38.9%), concerns that the alterations were permanent (35.4%), and physical implications and difficulty performing activities of daily living (34%) were reported.

Conclusion

Anosmia and dysgeusia are prevalent symptoms of COVID-19 disease, especially among females. Although transient, anosmia and dysgeusia had considerable impact on patient's life. Neuropsychological implications of COVID-19 in acute infection phase and prognosis of anosmia and dysgeusia in COVID-19 are areas for further exploration.

Evaluation of children and adults with post-COVID-19 persistent smell, taste and trigeminal chemosensory disorders: A hospital based study

BACKGROUND

Smell disorders are the most frequent persistent coronavirus disease 2019 (COVID-19) complications.

AIM

To describe the patterns and characteristics of persistent smell and taste disorders in Egyptian patients.

METHODS

Assessment was done to 185 patients (adults = 150, age: 31.41 ± 8.63 years; children = 35; age: 15.66 ± 1.63 years). Otolaryngology and neuropsychiatric evaluations were done. Measurements included: A clinical questionnaire (for smell and taste); sniffin' odor, taste and flavor identification tests and the Questionnaire of Olfactory Disorders-Negative Statements (sQOD-NS).

RESULTS

Duration of disorders was 11.53 ± 3.97 ms (6-24 ms). Parosmia (n = 119; 64.32%) was developed months after anosmia (3.05 ± 1.87 ms). Objective testing showed anosmia in all, ageusia and flavor loss in 20% (n = 37) and loss of nasal and oral trigeminal sensations in 18% (n = 33) and 20% (n = 37), respectively. Patients had low scoring of sQOD-NS (11.41 ± 3.66). There were no specific differences in other demographics and clinical variables which could distinguish post-COVID-19 smell and taste disorders in children from adults.

CONCLUSION

The course of small and taste disorders are supportive of the nasal and oral neuronal compromises. Post-COVID-19 taste and trigeminal disorders were less frequent compared to smell disorders. Post-COVID-19 flavor disorders were solely dependent on taste and not smell disorders. There were no demographics, clinical variables at onset or specific profile of these disorders in children compared to adults.

Omega-3 Fatty Acid Supplementation for the Treatment of Persistent COVID-Related Olfactory Dysfunction

OBJECTIVE

To evaluate the efficacy of omega-3 fatty acid (O3FA) supplementation in the treatment of COVID-related olfactory dysfunction (OD).

METHODS

Patients with laboratory-confirmed or clinically-suspected COVID-19 infection and new-onset OD from August 2020 to November 2021 were prospectively recruited. Patients with quantitative OD, defined as a brief smell identification test (BSIT) score of 9 or less, were eligible for study inclusion. The experimental group received 2 g of O3FA supplementation, while the control group received an identical placebo to be taken daily for 6 weeks. The primary outcome was a change in BSIT score between the initial and 6-week follow-up tests.

RESULTS

One hundred and seventeen patients were included in the analysis, including 57 patients in the O3FA group and 60 in the placebo group. O3FA group patients demonstrated a mean BSIT improvement of 1.12 ± 1.99 compared to 0.68 ± 1.86 in the placebo group (p = 0.221). Seventy-seven patients, 42 within the O3FA group and 35 in the placebo group, completed a follow-up BSIT survey at an average of 717.8 days from study onset. At long-term follow-up, there was an average BSIT score improvement of 1.72 within the O3FA group compared to 1.76 within the placebo group (p = 0.948).

CONCLUSION

Among patients with persistent COVID-related OD, our study showed no clear evidence of relative short-term or long-term olfactory recovery among patients receiving high doses of O3FA supplementation.

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

Objective

To evaluate the reliability and validity of the Italian brief-QOD (Brief-IT-QOD).

Methods

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 (CRSwNP) patients before and after biologic therapy), and cut-off value determination (ROC curve analysis of Brief-IT-QOD sensitivity and specificity).

Results

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.

Conclusions

Brief-IT-QOD is reliable, valid, responsive to changes in QoL, and recommended for clinical practice and outcome research.

Olfactory Disorders Questionnaire: Scaling severity of quality-of-life impact

BACKGROUND

The Olfactory Disorders Questionnaire (ODQ) is widely used for patients suffering from olfactory disorders to depict the impact on quality of life. The aim of this study was to scale and produce reference values for patients ODQ score according to Becks Depression Inventory (BDI) severity.

METHODS

In this prospective study, a cross-sectional anonymous survey was created, which combined EQ-5D-5L, BDI and ODQ. Correlation was calculated between the three questionnaires. Receiver operator characteristic curves were created to produce cut-off values for ODQ scores based on three BDI categories (mild, borderline clinical and moderate-to-severe depression).

RESULTS

Of the 578 who responded to the survey, 445 completed all sections and were included in the study. Majority were female (n = 327,73.5%), median age group 55-70 years (n = 193,43.4%). There was a strong correlation between BDI score and total ODQ score. There was a clear gradient in total ODQ score for each BDI classification; those with mild depression had the lowest mean ODQ score (101.8, range 39-168), those with moderate-to-severe depression had the highest (138.24, range 74-177). Due to overlapping of confidence intervals we were unable to grade the ODQ score.

CONCLUSION

The study was unable to generate reference values for the ODQ due to lower numbers of patients with borderline clinical to extreme depression. However, we were able to appreciate the general trend, that the higher the ODQ score, the higher the risk of depression. These findings should guide clinical practice to ensure appropriate care and support is provided for those with olfactory dysfunction.

Neurological manifestations in SARS-CoV-2 infection: A single-center cross-sectional study in Malaysia

Background

Neurological involvement associated with SARS-CoV-2 infection has been reported from different regions of the world. However, data from South East Asia are scarce. We described the neurological manifestations and their associated factors among the hospitalized COVID-19 patients from an academic tertiary hospital in Malaysia.

Methods

A cross-sectional observational study of hospitalized COVID-19 patients was conducted. The neurological manifestations were divided into the self-reported central nervous system (CNS) symptoms, stroke associated symptoms, symptoms of encephalitis or encephalopathy and specific neurological complications. Multiple logistic regression was performed using demographic and clinical variables to determine the factors associated with outcome.

Results

Of 156 hospitalized COVID-19 patients with mean age of 55.88 ± 6.11 (SD) years, 23.7% developed neurological complications, which included stroke, encephalitis and encephalopathy. Patients with neurological complications were more likely to have diabetes mellitus (p = 0.033), symptoms of stroke [limb weakness (p < 0.001), slurred speech (p < 0.001)]; and encephalitis or encephalopathy [confusion (p < 0.001), forgetfulness (p = 0.006) and seizure (p = 0.019)]. Unvaccinated patients had a 4.25-fold increased risk of having neurological complications (adjusted OR = 4.25; 95% CI: 1.02, 17.71, p = 0.047). Anosmia and dysgeusia were less associated with neurological complications (adjusted OR = 0.22; 95% CI: 0.05, 0.96, p = 0.044). The odds of neurological complications were increased by 18% in patients with leukocytosis (adjusted OR = 1.18, 95% CI: 1.003, p = 0.0460).

Conclusions

Stroke, encephalitis and encephalopathy were the common neurological complications from our study. Diabetes mellitus, presence of symptoms of stroke, symptoms of encephalitis or encephalopathy, leukocytosis, and being unvaccinated against COVID-19 were the associated risk factors of developing neurological complications.

Cross-Cultural Validation of the Short Version of the Questionnaire of Olfactory Disorders-Negative Statements into Italian: Towards Personalized Patient Care

Given the high burden of olfactory dysfunction worldwide, recently increased due to the COVID-19 pandemic, it is mandatory to adopt a specific questionnaire to assess the impact of olfactory impairment on quality of life, to be used in clinical practice. The aim of this study is to adapt and validate the short version of the Questionnaire of Olfactory Disorders-Negative Statements (svQOD-NS) for Italian. In the pilot phase, the Italian version of the questionnaire (ITA-svQOD-NS) was produced following recommended guidelines. It was then given to 50 healthy subjects and 50 patients (affected by either nasal polyposis or septal deviation), and results were compared to those of other widely used questionnaires. Test-retest reliability was assessed on a sample of 25 patients. All 50 patients repeated the questionnaires at one and nine months after surgery. The internal consistency of ITA-svQOD-NS measured with Cronbach α was excellent (α = 0.92). The intraclass correlation coefficient for test-retest reliability was also optimal (0.93; 95%CI: 0.90-0.96). Concurrent validity tested with the Pearson coefficient was significant with all other tests administered; also, concerning responsiveness, statistically significant differences were obtained between pre- and post-operative conditions. ITA-svQOD-NS showed high internal consistency, test-retest reliability, and significant correlation with all most-used clinical questionnaires; thus, it can be efficiently applied to assess olfaction-related QoL in the Italian population.

Validity and reliability of the Malay Short Version of the Questionnaire of Olfactory Disorders-Negative Statements (sQOD-NS)

Background

Olfaction plays an enormous role in every aspect of life including health, emotions, social life, and safety. This is why olfactory dysfunction will leave a great impact on a person’s life. During the recent pandemic hit of coronavirus 2019 (COVID-19), much importance was given to olfaction and its sequelae post-COVID-19. There is various questionnaire being used for determining olfactory disorders worldwide. In Malaysia, Malay language is widely conversed among the local population hence an assessment tool for an olfactory specific quality of life is necessary.

Method

This is a cross-sectional study performed in the Otorhinolaryngology clinic in a tertiary hospital. The short Questionnaire of Olfactory Disorders-Negative Statements (sQOD-NS) is a validated questionnaire that is a simple and easy tool to assess the impact of olfactory dysfunction in daily life. The original version of the short Questionnaire of Olfactory Disorders-Negative Statements (sQOD-NS) questionnaire was translated into the Malay language. A forward-backwards translation, validity, and reliability study was done on this questionnaire. A Malay version of sQOD-NS was responded to by a total of 70 participants including 35 patients of normosia and 35 patients with smell dysfunction and repeated after 2 weeks via phone call response. The discriminant validity, internal consistency, and test re-test reliability were assessed.

Results

The pilot study revealed that participants who were normosmic had a higher mean score than smell dysfunction. A Student t test shows mean 20.5 ± 1.22 in normosmic group and 6.06 ± 2.41 in hyposmic group which are significant with p value of < 0.01. The coefficient of correlation (r) between test and retest scores was 0.77 (P < 0.001).

Conclusion

The Malay translation of sQOD-NS is a validated questionnaire that can be used both in clinical practice and in academics.

The incidence and impact of anosmia on daily life after COVID-19 infection: A cross-sectional study in a tertiary center in Saudi Arabia

OBJECTIVES

To investigate the impact of olfactory dysfunction's (OD) on patients with coronavirus disease-19 (COVID-19) and evaluate the risk factors associated with it.

METHODS

This cross-sectional study analyzed patients who tested positive for COVID-19 over a period of 4 months (May-July 2020) and experienced OD and mild illness. Selected patients were given 2 scales Olfactory Disorders Negative Statement (QOD-NS) and Sino-nasal Outcome Test (SNOT-22).

RESULTS

A total of 256 patients were enrolled, out of which 196 had anosmia after COVID-19 infection. More than 75% of the participants were aged between 20-40 years and 64.3% were women. The mean score of the patients was 25.13 (SD 19.6) on the SNOT-22, while it was 4.9 (SD 4.85) on the QOD-NS. There was no association between anosmia and other comorbidities and factors (age, smoking history, allergic rhinitis history, asthma, and so on). Only 39% of patients who had anosmia after COVID-19 recovered in less than 4 months.

CONCLUSION

Olfactory dysfunction is a common symptom of COVID-19 infection and it can take more than 4 months to recover. Nevertheless, this cohort reports a moderate impact on their quality of life due to anosmia.

Impact of Hedonics and Magnitude Upon Validated Psychophysical Olfactory Tests and Olfactory-Specific Quality of Life

Introduction

Patients often describe the olfactory loss as either the inability to detect unpleasant odors (eg, smoke or spoiled food) or noticeable impairment in enjoying pleasant odors (eg, food and fragrances). This complex relationship between the hedonics of various odors, their perceived magnitude in odor strength, and the impact on patient quality of life is not well understood.

Methods

Sixty-five subjects underwent testing with the Henkin olfaction test which assesses hedonics and magnitude for odors traditionally deemed unpleasant (pyridine/dead fish and thiophene/gasoline) and pleasant (amyl acetate/banana and nitrobenzene/almond). Subjects also completed Smell Identification Test-40 (SIT-40), Sniffin’ Sticks (Sniffin’ Sticks), and Snap & Sniffin’ Sticks (Snap) Olfactory Tests, as well as the 17-item Questionnaire for Olfactory Disorders Negative Statements (QODNS) and olfactory symptom visual analog scale (VAS). Spearman's rank correlations were conducted between various olfactory domains, QODNS and VAS.

Results

Mean age was 52.1 years (range: 28-86), with 63.1% females. Magnitude estimation was greatest for pyridine. Most people rated thiophene (75.4%) and pyridine (92.3%) as “unpleasant.” Although most people rated amyl acetate (47.7%) and nitrobenzene (56.9%) as “pleasant,” many rated amyl acetate (52.3%) and nitrobenzene (43.1%) as “neutral” or “unpleasant” scents. Hedonics for unpleasant odors correlated with each other ( rs = 0.60), but not with hedonics for pleasant odors. Hedonics for unpleasant odors also correlated with magnitude estimation and other psychophysical tests. These findings were not seen for hedonics of pleasant odors.

Conclusions

The use of unpleasant odors in Henkin testing showed unique relationship patterns with patient-reported outcome measures and validated olfactory tests, which may provide utility in characterizing olfactory dysfunction. The incorporation of more unpleasant odors in current psychophysical olfactory testing may provide enhanced information regarding the patient impact of olfactory dysfunction.

Olfactory dysfunction in COVID-19, new insights from a cohort of 353 patients: The ANOSVID study

Olfactory disorders (OD) pathogenesis, underlying conditions, and prognostic in coronavirus disease 2019 (COVID-19) remain partially described. ANOSVID is a retrospective study in Nord Franche-Comté Hospital (France) that included COVID-19 patients from March 1 2020 to May 31 2020. The aim was to compare COVID-19 patients with OD (OD group) and patients without OD (no-OD group). A second analysis compared patients with anosmia (high OD group) and patients with hyposmia or no OD (low or no-OD group). The OD group presented less cardiovascular and other respiratory diseases compared to the no-OD group (odds ratio [OR] = 0.536 [0.293-0.981], p = 0.041 and OR = 0.222 [0.056-0.874], p = 0.037 respectively). Moreover, history of malignancy was less present in the high OD group compared with the low or no-OD group (OR = 0.170 [0.064-0.455], p < 0.001). The main associated symptoms (OR > 5) with OD were loss of taste (OR = 24.059 [13.474-42.959], p = 0.000) and cacosmia (OR = 5.821 [2.246-15.085], p < 0.001). Most of all ORs decreased in the second analysis, especially for general, digestive, and ENT symptoms. Only two ORs increased: headache (OR = 2.697 [1.746-4.167], p < 0.001) and facial pain (OR = 2.901 [1.441-5.842], p = 0.002). The high OD group had a higher creatinine clearance CKD than the low or no-OD group (89.0 ± 21.1 vs. 81.0 ± 20.5, p = 0.040). No significant difference was found concerning the virological, radiological, and severity criteria. OD patients seem to have less comorbidity, especially better cardiovascular and renal function. Associated symptoms with OD were mostly neurological symptoms. We did not find a significant relationship between OD and less severity in COVID-19 possibly due to methodological bias.

Could melatonin have a potential adjuvant role in the treatment of the lasting anosmia associated with COVID-19? A review

INTRODUCTION

Anosmia, the loss of the sense of smell, is usually associated with rhinopathies and has been reported as a common symptom of COVID-19. There is no specific drug to treat this condition, although some evidence suggests that melatonin could promote the recovery of olfactory sensory neurons.

METHODS

We set out to perform a narrative review to synthesize the current evidence in this area in respect of our hypothesis that melatonin may be linked with anosmia and play a part in oxidative stress and the regulation of inflammation. The main electronic databases (MEDLINE/PubMed, Embase, and Cochrane) were searched.

RESULTS

The search produced 26 articles related to our hypothesis. Some studies examined issues related to melatonin's effects and its use as adjuvant therapy for COVID-19. Despite some studies suggesting that melatonin may have potential in the treatment of COVID-19, to the best of our knowledge, there have been no trials that have used it to treat anosmia associated with the disease. Few articles identified proposed that melatonin might have an effect on olfactory cells.

DISCUSSION

Further experimental and clinical research on the role of circadian melatonin in the olfactory system is warranted. This will provide evidence of the use of melatonin in the management of anosmia. A number of identified studies suggest that the imbalanced release of melatonin by the pineal gland associated with sleep disturbance may play a role in anosmia, although the specific pathway is not yet entirely clear. This may be a base for further research into the potential role of melatonin as adjuvant treatment of anosmia.

Asthma and Cacosmia Could Be Predictive Factors of Olfactory Dysfunction Persistence 9 Months after SARS-CoV-2 Infection: The ANOSVID Study

Background. Long-term evolution data of olfactory disorders (OD) in COVID-19 are limited. Method. ANOSVID is a retrospective study in Nord Franche-Comté Hospital (France) that included COVID-19 patients from the first wave. The aim was to describe OD evolution, especially in patients with persistent OD (p-OD group) in comparison with patients with resolved OD (r-OD group). Results. Among 354 COVID-19 patients, 229 reported OD were included. Eighty-five percent of patients (n = 195) recovered from their OD within 90 days. However, 9.5 months (in average) after symptoms onset, OD were persisting in 93 patients (40.6%) and resolved in 136 patients (59.4%). In the p-OD group (n = 93), the mean age was 51.4 years (19-98) ± 20.2, and 65 patients (69.9%) were female; the three main comorbidities in the p-OD group were: asthma (20.4%, n = 19), allergic rhinitis (19.4%, n = 18), and arterial hypertension (16.1%, n = 15). Eleven patients (12%) presented anosmia, and 82 patients (88%) presented hyposmia. Asthma was more described in p-OD group than r-OD group (19 (20.4%) versus 10 (7.4%), p = 0.006). Cacosmia was more described in p-OD group than r-OD group (27 (29.0%) versus 18 (13.2%), p = 0.005). There was no significant difference between the two groups concerning other comorbidities and symptoms, clinical, biological, and imaging findings, and outcome or about the impact of OD on the quality of life of the patients between the p-OD group and r-OD group. sQOD-NS brief version score was 10.7 ± 5.89 and 12.0 ± 6.03, respectively (p = 0.137). Conclusion. Forty-one percent of patients with OD reported OD persistence 9.5 months after COVID-19 (hyposmia in 88% of cases). Asthma and cacosmia could be predictive factors of OD persistence.

Predictive significance of the questionnaire of olfactory disorders-negative statements for olfactory loss in patients with chronic rhinosinusitis

Objectives

The questionnaire of olfactory disorder-negative statements (QOD-NS) is a valid and reliable instrument for assessing the olfactory-specific quality of life. This study aimed to explore the association between the QOD-NS and objective olfactory metrics (including objective olfactory cleft assessment) and then evaluate the predictive significance of the QOD-NS for olfactory loss in Chinese patients with chronic rhinosinusitis (CRS).

Methods

A total of 70 patients with CRS were enrolled in the study. Olfaction was assessed with Sniffin’ Sticks. The olfactory cleft was assessed by the sinus CT scan and nasal endoscopy (the Lund–Mackay olfactory cleft scale, LM-OC and olfactory cleft endoscopy scale, OCES). The QOD-NS and its short version were utilized to assess the patient-reported olfaction. The predictors associated with olfactory loss were analyzed by the logistic regression analysis. The optimal cutoff points of the predictors were determined by the receiver-operating characteristic curves and the Youden index.

Results

The TDI score in patients with CRS significantly correlated with the QOD-NS (r = − 0.755, P < 0.001), OCES (r = − 0.520, P < 0.001), LM-OC (r = − 0.615, P < 0.001). After adjusting for patient demographics and comorbidities, QOD-NS was significantly associated with olfactory dysfunction [odds ratio (OR) = 1.243; P = 0.001] and anosmia in patients with CRS (OR = 1.838; P = 0.006). Furthermore, the QOD-NS significantly correlated with the LM-OC (r = 0.610, P < 0.001), and the OCES (r = 0.464, P < 0.001) in patients with CRS. The QOD-NS had the highest predictive value for olfactory dysfunction (optimal cutoff = 10.5; Youden index = 0.635; area under the curve = 0.861) and anosmia (optimal cutoff = 20.5; Youden index = 0.790; area under the curve = 0.928) in patients with CRS.

Conclusion

The QOD-NS showed high validity and correlated well with objective olfactory metrics and olfactory cleft assessment in patients with CRS. The QOD-NS was a reliable predictor for olfactory dysfunction and anosmia in patients with CRS, which may aid in the fast screening of olfactory loss in the clinic.

Olfactory Training in Post-COVID-19 Persistent Olfactory Disorders: Value Normalization for Threshold but Not Identification

(1) Background: Persistent post-viral olfactory disorders (PPVOD) are estimated at 30% of patients one year after COVID-19 infection. No treatment is, to date, significantly effective on PPVOD with the exception of olfactory training (OT). The main objective of this work was to evaluate OT efficiency on post-COVID-19 PPVOD. (2) Methods: Consecutive patients consulting to the ENT department with post-COVID-19 PPVOD were included after completing clinical examination, the complete Sniffin’ Stick Test (TDI), the short version of the Questionnaire of olfactory disorders and the SF-36. Patients were trained to practice a self-olfactory training with a dedicated olfactory training kit twice a day for 6 months before returning to undergo the same assessments. (3) Results: Forty-three patients were included and performed 3.5 months of OT in average. We observed a significant TDI score improvement, increasing from 24.7 (±8.9) before the OT to 30.9 (±9.8) (p < 0.001). Based on normative data, a significant increase in the number of normosmic participants was observed only for the threshold values (p < 0.001). Specific and general olfaction-related quality of life improved after the OT. (4) Conclusions: Olfactory function appeared to improve only in peripheral aspects of post-COVID-19 PPVOD after OT. Future controlled studies must be performed to confirm the OT role and justify new therapeutic strategies that may focus on the central aspects of post-COVID-19 PPVOD.

Effect of early olfactory training on olfactory recovery after nasal endoscopy in patients with chronic rhinosinusitis and olfactory impairment

OBJECTIVE

To analyze the effect of early comprehensive olfactory rehabilitation training on olfactory recovery after nasal endoscopy in patients with chronic rhinosinusitis and olfactory impairment.

METHODS

A retrospective study was conducted on 67 patients with chronic rhinosinusitis combined with olfactory impairment in our hospital from July 2018 to August 2020. Patients were divided into control group and observation group according to the time of implementing comprehensive olfactory rehabilitation training. The control group received non-early comprehensive olfactory rehabilitation training at 2 weeks after nasal endoscopy, and the observation group received early comprehensive olfactory rehabilitation training at 1 week after nasal endoscopy. The minimum detection/recognition threshold, olfactory threshold, olfactory function and quality of life were compared between the two groups.

RESULTS

After 3 months of training, T&T olfactory test scores in the observation group were significantly lower than those in the control group (P<0.05). The minimum detection scores in the observation group were lower than those in the control group after 1, 2 and 3 months of training, and the recognition scores in the observation group were higher than those in the control group (P<0.05). The scores of olfactory threshold, odor discrimination, and odor identification of the observation group after 1, 2 and 3 months of training were higher than those of the control group (P<0.05). After 3 months of training, the self-description scores of quality-of-life questionnaires in the observation group were higher than those in the control group, and visual analogue scale (VAS) scores in the observation group were lower than those in the control group (P<0.05).

CONCLUSION

Early comprehensive olfactory training can improve the olfactory threshold and odor discrimination of patients with chronic rhinosinusitis combined with olfactory impairment after nasal endoscopy, improve the quality of life, and have a positive effect on olfactory recovery.

Olfactory Dysfunction in Patients With Coronavirus Disease 2019: A Review

The coronavirus disease 2019 (COVID-19) pandemic is wreaking havoc on public-health and economic systems worldwide. Among the several neurological symptoms of patients with COVID-19 reported in clinical practice, olfactory dysfunction (OD) is the most common. OD occurs as the earliest or the only clinical manifestation in some patients. Increasing research attention has focused on OD, which is listed as one of the main diagnostic symptoms of severe acute respiratory syndrome-coronavirus-2 infection. Multiple clinical and basic-science studies on COVID-19-induced OD are underway to clarify the underlying mechanism of action. In this review, we summarize the clinical characteristics, mechanisms, evaluation methods, prognosis, and treatment options of COVID-19-induced OD. In this way, we hope to improve the understanding of COVID-19-induced OD to aid early identification and precise intervention.

Reliability and validity of a brief version of the Questionnaire of Olfactory Disorders (brief QOD) in patients with olfactory dysfunction

BACKGROUND

The aim of this study was to determine the reliability and validity of the brief version of Questionnaire of Olfactory Disorders (brief QOD).

METHODS

A total of 372 patients participated in this study. Olfactory function was examined using the Sniffin' Sticks test. The brief version of QOD, including 4 items concerning parosmia (QOD-P), 7 items concerning quality of life (QOD-QOL), and 3 visual analog scales to rate disease burden, awareness of the disorder and issues related to professional life (QOD-VAS), was used to assess subjective information on olfactory dysfunction. We evaluated the split-half reliability, internal consistency and validity of the brief QOD.

RESULTS

The split-half reliability was 0.60 (QOD-P), 0.87 (QOD-QOL), and 0.66 (QOD-VAS), respectively. The Cronbach's α coefficient was 0.63 (QOD-P), 0.87 (QOD-QOL), and 0.71 (QOD-VAS), respectively. Olfactory function was found to be associated with QOD-P, QOD-QOL and QOD-VAS.

CONCLUSIONS

The brief QOD is a suitable scale for the assessment of subjective severity of olfactory dysfunction for purposes such as treatment counseling, disability assessment, treatment control, and research in patients with olfactory disorder.

Clinical Features of Parosmia Associated With COVID-19 Infection

Objective

To characterize the clinical features, risk factors, symptom time‐course, and quality of life implications for parosmia among coronavirus disease (COVID)‐related olfactory dysfunction patients.

Methods

Individuals with olfactory dysfunction associated with laboratory‐confirmed or clinically suspected COVID‐19 infection were recruited from otolaryngology and primary care practices over a period from August 2020 to March 2021. Participants completed olfactory dysfunction and quality of life surveys.

Results

A total of 148 (64.1%) of 231 respondents reported parosmia at some point. Parosmia developed within 1 week of any COVID‐19 symptom onset in 25.4% of respondents, but more than 1 month after symptom onset in 43.4% of respondents. Parosmia was associated with significantly better quantitative olfactory scores on Brief Smell Identification Test (8.7 vs. 7.5, P = .006), but demonstrated worse quality of life scores, including modified brief Questionnaire of Olfactory Dysfunction—Negative Statements and Sino‐Nasal Outcome Test‐22 scores (12.1 vs. 8.5, P < .001; 26.2 vs. 23.2, P = .113). Participants who developed parosmia at any point were significantly younger and less likely to have history of chronic sinusitis than those who did not develop parosmia (40.2 vs. 44.9 years, P = .007; 7.2% vs. 0.7%, P = .006).

Conclusion

COVID‐19‐associated olfactory dysfunction is frequently linked with development of parosmia, which often presents either at onset of smell loss or in a delayed fashion. Despite better quantitative olfactory scores, respondents with parosmia report decreased quality of life. A majority of respondents with persistent parosmia have sought treatment.

Level of Evidence

3 Laryngoscope, 132:633–639, 2022

What about using sniffin' sticks 12 items test to screen post-COVID-19 olfactory disorders?

Background

Post-COVID-19 Olfactory impairment has a negative impact on quality of life. The Sniffin Sticks test 12 items (SST-12) can be used in quick olfactory disorders screening. Its evaluation in a post-covid-19 situation was the main objective of this work.

Methods

All patient impaired with a post-COVID olfactory loss were included while consulting to the ENT department. The clinical examination included an olfaction recovery self-assessment (VAS), a nasofibroscopy, a quality of life (QoL) assessment, the complete Sniffin’ Sticks Test (SST), and the SST-12.

Results

Among the 54 patients included, 92% (n = 50) were correctly screened as olfactory impaired by SST-12. We report excellent correlations between SST-12 and SST (rho ₍₅₂₎ = 0.98, p < 0.001), QoL(rho₍₅₂₎ = 0.33 p = 0.016), or VAS (rho₍₅₂₎ = 0.49, p < 0.001) assessments.

Conclusions

SST-12 is a quick and reliable tool to screen large-scale population of post-COVID-19 olfactory impaired patients and could be used in a general daily clinical practice.

Psychometric properties of the brief version of the questionnaire of olfactory disorders in patients with chronic rhinosinusitis

BACKGROUND

The Questionnaire of Olfactory Disorders-Negative Statements (QOD-NS) is a 17-item instrument measuring olfactory-specific quality of life (QOL). However, in clinical research patients can be overwhelmed with multiple questionnaires. We recently developed the 7-item brief QOD-NS (B-QOD). Our objective was to evaluate the psychometric properties of the B-QOD in both the development (D) sample, and in a separate replication (R) sample.

METHODS

Testing on D (n = 203) and R (n = 281) samples included initial exploratory factor analysis (EFA), followed by internal reliability, information loss, and confirmatory factor analysis (CFA). Finally, incremental predictive utility analysis (IPUA) was performed by correlating the B-QOD with the 22-item Sino-Nasal Outcome Test (SNOT-22) survey.

RESULTS

EFAs of both D and R demonstrated an underlying single-factor structure (eigenvalue = 4.17 and 3.57, respectively) with comparable loading factors (R > 0.30 for both). B-QOD also had good internal reliability in both D and R (Cronbach's alpha = 0.88 and 0.83, respectively). Also, there is minimal information loss with B-QOD compared to QOD-NS in both D and R (R = 0.98 and 0.96, respectively). CFA indicates that the B-QOD single-factor model has good overall fit as measured by the Comparative Fit Index (CFI) and the Standardized Root Mean Squared Residuals (SRMSR) in the D and R samples (CFI = 0.99 and 0.97; SRMSR = 0.035 and 0.053). IPUA shows that the QOD-NS offers no additional predictive benefit of SNOT-22 scores when compared with B-QOD.

CONCLUSION

The 7-item B-QOD captures a structurally coherent and reliable single dimension, with minimal information loss and excellent external predictive utility when compared to the QOD-NS.

Persistent olfactory complaints after COVID-19: a new interpretation of the psychophysical olfactory scores

Background: Sudden olfactory loss is a major symptom of SARS-CoV-2 infection and has a negative impact on daily life quality. Almost 80% of disorders regress spontaneously. No precise characterization of the medium- and long-term olfactory symptoms has been carried out yet, apart from self-assessments. The main objective of this work was to characterize persistent smell disorders in this population. Methodology: Consecutive patients consulting to the ENT department with post-Covid19 olfactory loss were included. The clinical examination included an analog scale for the self-assessment of olfactory recovery), a nasofibroscopy, the Sniffin’ Stick Test and the short version of the Questionnaire of olfactory disorders. Results: Among the 34 patients included, based on the Sniffin’ Sticks Test, 29.4% (n=10) could be classified as normosmic, 55.9% (n=19) as hyposmic and 14.7% (n=5) as functional anosmic). Only olfactory identification impairment was significantly correlated with olfactory complaint and daily anxiety and annoyance related to lack of olfaction recovery. This identification disorder seemed to worsen over time. Conclusions: It is crucial to assess odor identification disorders in case of persistent olfactory complaints after COVID-19. It is fundamental to target this disorder, as it does not improve spontaneously and negatively impact quality of life.

Olfactory and Gustatory Dysfunction in COVID-19 Patients: A Tertiary Care Institute Experience in India

COVID-19 epidemic has varied spectrum of symptoms. With this study we aim to evaluate prevalence of Olfactory and Gustatory dysfunction in COVID-19 patients. To assess Olfactory and Gustatory dysfunction in COVID-19 Patients in Indian Population. Settings and Design: Prospective observational study. RT-PCR proven COVID-19 patients were enrolled in the study. Detailed history and olfactory function and Taste function were evaluated. Patient with symptoms of olfactory dysfunction were subjected to fill (sQOD-NS questionnaire). Re-evaluation was done weekly till the time of discharge. Analysis was done with Wilcoxon test with help of SPSS software. A total of 152 patients (Male-78, Female-74) completed the study after weekly evaluation. Olfactory and Gustatory dysfunction was seen in 28 (18.41%) and 20 (13.15%). Mean duration of symptoms was 2.4444 ± 0.352 days. Olfactory dysfunction was the first presenting symptom in 11 out of 152 patients (7.23%). Mean QD-NOS score in patients with Anosmia and Hyposmia (28 patients) was 11.4 ± 2.01 and 13.61 ± 2.82 at 1st evaluation, 20.3 ± 1.49 and 20.33 ± 1.57 at 7th day and 21 in both subgroups at 14th day follow up. Dysgeusia was noticed in 20/152 patients (13.15%). Recovery in olfactory dysfunction and Dysgeusia was complete in all patients. Olfactory and gustatory dysfunctions are significant part of clinical spectrum of COVID-19 disease In Indian Population.

Translation and validation of the short version of the Questionnaire of Olfactory Disorders-Negative Statements to Spanish

INTRODUCTION

There are more than 400 million of native Spanish speakers around the world, being the second most spoken language in regard to the number of native speakers. For this reason, a valid questionnaire to access the olfaction of our patients is necessary.

MATERIAL AND METHODS

Validation and cross-cultural adaptation of the svQOD-NS questionnaire to the Spanish language. Internal consistency of svQOD-NS measured with Cronbach α.

RESULTS

40 patients met the inclusion criteria. 41 ± 153 (range 21-82), and 32 (80%) were female. 20 patients (57,1%) were male and 15 (42,9%) were female. There was a normal distribution among patients included according to the Shapiro-Wilk test (p = 0.175). Internal consistency of svQOD-NS measured with Cronbach α was 0.861. The intraclass correlation coefficient was 0.849 (confidence interval [CI] 95%: 0.766-0.911).

CONCLUSION

The Spanish Language is the second most spoken language with regard to the number of native speakers and the svQOD-NS translation represents a valid option for the Spanish-speaking medical community, from which a large number of patients can benefit.

Study of Clinical and Biological Characteristics of Moroccan Covid-19 Patients With and Without Olfactory and/or Gustatory Dysfunction

Background

The epidemic of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), causing coronavirus disease 2019 (COVID-19), presents a significant and urgent threat to global health. This alarming viral infection, declared as pandemic by the WHO in February 2020, has resulted millions of infected patients and thousands of deaths around the world. In Morocco, despite the efforts made by the authorities, the SARS-CoV-2 continues to spread and constitutes a burden of morbidity and mortality. The objective of this study is to describe clinical characteristics of COVID-19 Moroccan patients and to establish the relationship between specific clinical symptoms, namely ageusia and/or anosmia, with these characteristics.

Methods

We performed a descriptive, non-interventional cross-sectional study analyzing data from 108 patients admitted to the VINCI clinic, Casablanca (Morocco). The database includes 39 parameters including epidemiological characteristics, anthropometric measurements and biological analyzes.

Results

The average of age of the patients was 43.80 ± 15.75 years with a sex ratio of 1:1. The mean body mass index of the patients was 25.54 ± 4.63 Kg/m². The majority of patients had, at least, one comorbidity and among 75% symptomatic patients, about 50% had, at least, three symptoms namely, fever (40.7%), cough (39.8%), myalgia (28.7%), and anosmia and/or ageusia (20.4%). From biological analyzes, we noticed lymphopenia and an elevated protein C reactive and lactate dehydrogenases levels in 24.1, 36.1, and 35.2% of patients, respectively. A disturbance in liver function markers was observed in 15.7% of cases. For the other hemostasis parameters, high levels of prothrombin and platelets were reported in 14.6 and 14.8% of patients, respectively. Comparisons related to the presence of anosmia and/or ageusia did not show any difference for demographic and anthropometric characteristics, while a possibility of a significant difference was revealed for certain biological parameters, particularly the levels of lymphocytes, D-dimer and troponin.

Conclusion

This study provides significant findings that will be used not only to supplement previous studies carried out in Morocco in order to resume the epidemiological situation in comparison with other countries, but also to improve the quality of the diagnosis of COVID-19 patients by identifying all the symptoms of the disease and better understanding its clinical outcomes.

Evaluation of Olfactory Acuity in Patients with Coronavirus Disease 2019 (COVID-19)

Aim and Objectives

To describe the prevalence and characteristics of olfactory dysfunction (OD) in patients with laboratory-confirmed COVID-19 infection.

Materials and Methods

This monocentric study was performed at Chest Diseases Hospital during the COVID-19 pandemic and all patients testing positive for COVID-19 over a 5-month period (April to August 2020) were recruited. Detailed history was elicited from subjects and all patients were inquired about olfactory dysfunction (OD). Patients with olfactory dysfunction were asked to complete olfactory questionnaires based on the short version of the Questionnaire of Olfactory Disorders-Negative Statements (sQOD-NS).

Results

655 patients with mild to moderate COVID-19 infection were included in the study. The prevalence rate of olfactory dysfunction was 18.47% (n = 121) with contribution of 11.60% (n = 76) and 6.87% (n = 45) from anosmia and hyposmia respectively, thereby suggesting olfactory dysfunction to be a significant clinical feature in COVID-19 patients. Males were significantly more affected by olfactory dysfunctions than females. Anosmic patients had significantly reduced sQOD-NS results as compared to hyposmic patients (significant at P < 0.05). The mean duration of OD was 7.7 days (± 4.3) and >90% patients in our study showed resolution within 14 days.

Conclusion

The early recognition of olfactory dysfunction should help to screen, identify and thereby quickly isolate mildly symptomatic COVID-19 patients from the general population and the existence of these dysfunctions may well be a prognostic factor in the course of the disease.

Olfactory disorders in coronavirus disease 2019 patients: a systematic literature review

OBJECTIVE

Recent scientific literature has widely described a possible major role of smell dysfunction as a specific symptom of coronavirus disease 2019. This systematic review may provide a more holistic approach to current knowledge of the disease.

METHODS

A systematic review was completed using Embase, PubMed and Web of Science databases that considered original articles focused on olfactory evaluation in coronavirus disease 2019 patients, published between March and May 2020, in English language.

RESULTS

From the 483 research papers initially identified, 32 original studies were selected, comprising a total of 17 306 subjects with a laboratory confirmed diagnosis of coronavirus disease 2019. Individual study sample sizes ranged from 6 to 6452 patients. This comprehensive analysis confirmed that olfactory disorders represent an important clinical feature in coronavirus disease 2019, with a prevalence of 11-100 per cent in included patients, although there was heterogeneity in terms of assessment tools and population selection criteria.

CONCLUSION

The results indicate that an accurate clinical evaluation should be carried out using structured questionnaires and tests with olfactory substances.

Symptomatology in head and neck district in coronavirus disease (COVID-19): A possible neuroinvasive action of SARS-CoV-2

OBJECTIVE

The aim of this manuscript is to investigate transversally Ear Nose Throat (ENT) symptoms COVID-19 infection correlated and to study the neurotropism and neuroinvasiveness of the virus in the head-neck district through the investigation of the sense of smell, taste, tearing, salivation and hearing.

METHODS

A total of 50 patients with laboratory-confirmed COVID-19 infection were included in our study. For each patient we evaluated the short version of the Questionnaire of Olfactory Disorders-Negative Statements (sQOD-NS), the Summated Xerostomia Inventory-Dutch Version (SXI-DV), The Standardized Patient Evaluation of Eye Dryness (SPEED), Schirmer test I, the Hearing Handicap Inventory For Adults (HHIA) and the Tinnitus Handicap Inventory (THI). All the tests we carried out were performed during the active phase of the symptomatology from COVID-19 (Condition A) and 15 after SARS-COV-2 RT-PCR test negative (Condition B).

RESULTS

A total of 46 patients (92%) had olfactory dysfunction related to the infection. The 70% of patients reported gustatory disorders. Cough, fever, headache and asthenia were the most prevalent symptoms. There was a statistically significant difference (p < 0,001) in sQOD-NS, SXI-DV, SPEED, Schirmer test, HHIA and THI between Condition A and Condition B.

CONCLUSIONS

In our population there was an alteration of the sense of taste, of the sense of smell, dry eyes and of the oral cavity and an auditory discomfort, symptoms probably linked to the neurotropism of the virus. Furthermore, anosmia, dysgeusia and xerostomia are early symptoms of COVID-19, which can be exploited for an early quarantine and a limitation of viral contagion.

Clinical and Radiological Evaluations of COVID-19 Patients With Anosmia: Preliminary Report

OBJECTIVES/HYPOTHESIS

To investigate clinical and radiological features of olfactory clefts of patients with mild coronavirus disease 2019 (COVID-19).

STUDY DESIGN

Prospective non controlled study.

METHODS

Sixteen COVID-19 patients were recruited. The epidemiological and clinical data were extracted. Nasal complaints were assessed through the 22-item Sino-Nasal Outcome Test. Patients underwent psychophysical olfactory testing, olfactory cleft examination, and computed tomography (CT) scans.

RESULTS

Sixteen anosmic patients were included. The mean Sniffin' Sticks score was 4.6 ± 1.7. The majority of patients had no endoscopical abnormality, with a mean olfactory cleft endoscopy score of 0.6 ± 0.9. The olfactory clefts were opacified in three patients on the CT scan. The mean radiological olfactory cleft score was 0.7 ± 0.8. There were no significant correlations between clinical, radiological, and psychophysical olfactory testing.

CONCLUSIONS

The olfactory cleft of anosmic COVID-19 patients is free regarding endoscopic examination and imaging. The anosmia etiology is not related to edema of the olfactory cleft.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:2526-2531, 2020.

Patterns of smell recovery in 751 patients affected by the COVID-19 outbreak

BACKGROUND AND PURPOSE

Post-viral olfactory dysfunction is well established and has been shown to be a key symptom of COVID-19 with more than 66% of European and US patients reporting some degree of loss of smell. Persistent olfactory dysfunction appears to be commonplace and will drive the demand for general practitioner, otolaryngology or neurology consultation in the next few months - evidence regarding recovery will be essential in counselling our patients.

METHODS

This was a prospective survey-based data collection and telemedicine follow-up.

RESULTS

In total, 751 patients completed the study, of whom 477 were females and 274 males. The mean age of the patients was 41 ± 13 years (range 18-60). There were 621 patients (83%) who subjectively reported a total loss of smell and 130 (17%) a partial loss. After a mean follow-up of 47 ± 7 days (range 30-71) from the first consultation, 277 (37%) patients still reported a persistent subjective loss of smell, 107 (14%) reported partial recovery and 367 (49%) reported complete recovery. The mean duration of the olfactory dysfunction was 10 ± 6 days (range 3-31) in those patients who completely recovered and 12 ± 8 days (range 7-35) in those patients who partially recovered.

CONCLUSIONS

According to our results, at this relatively early point in the pandemic, subjective patterns of recovery of olfactory dysfunction in COVID-19 patients are valuable for our patients, for hypothesis generation and for treatment development.

A structural equation model to examine the clinical features of mild-to-moderate COVID-19: A multicenter Italian study

The purpose of this study was to evaluate the clinical features of mild-to-moderate coronavirus disease 2019 (COVID-19) in a sample of Italian patients and to investigate the occurrence of smell and taste disorders. Infected individuals with suspected (clinical diagnosis) or laboratory-confirmed COVID-19 infection were recruited. Patients completed a survey-based questionnaire with the aim of assessing their epidemiological and clinical characteristics, general otorhinolaryngological symptoms, and smell and taste disorders. A total of 294 patients with mild-to-moderate COVID-19 completed the survey (147 females). The most prevalent general symptoms included fever, myalgia, cough, and headache. A total of 70.4% and 59.2% of patients reported smell and taste disorders, respectively. A significant association between the two above-mentioned disorders was found (rs: 0.412; P < .001). Smell disorders occurred before the other symptoms in 11.6% of patients and was not significantly associated with nasal obstruction or rhinorrhea. Interestingly, our statistical analysis did not show any significant difference, either for general symptoms or otorhinolaryngological features, between the clinical diagnosis group and the laboratory-confirmed diagnosis (polymerase chain reaction) group. The structural equation model confirmed significant standardized paths (P < .05) between general symptoms, comorbidities, and general otorhinolaryngological complaints in the absence of a significant correlation between these elements and smell and taste alterations. The prevalence of smell and taste disorders in mild-to-moderate Italian COVID-19 patients is significant both in suspected and laboratory-confirmed cases and reveals a strong correlation between these clinical signs regardless of the presence of general or otorhinolaryngological symptoms, such as nasal obstruction or rhinorrhea.

Olfactory and gustatory dysfunctions as a clinical presentation of mild-to-moderate forms of the coronavirus disease (COVID-19): a multicenter European study

OBJECTIVE

To investigate the occurrence of olfactory and gustatory dysfunctions in patients with laboratory-confirmed COVID-19 infection.

METHODS

Patients with laboratory-confirmed COVID-19 infection were recruited from 12 European hospitals. The following epidemiological and clinical outcomes have been studied: age, sex, ethnicity, comorbidities, and general and otolaryngological symptoms. Patients completed olfactory and gustatory questionnaires based on the smell and taste component of the National Health and Nutrition Examination Survey, and the short version of the Questionnaire of Olfactory Disorders-Negative Statements (sQOD-NS).

RESULTS

A total of 417 mild-to-moderate COVID-19 patients completed the study (263 females). The most prevalent general symptoms consisted of cough, myalgia, and loss of appetite. Face pain and nasal obstruction were the most disease-related otolaryngological symptoms. 85.6% and 88.0% of patients reported olfactory and gustatory dysfunctions, respectively. There was a significant association between both disorders (p < 0.001). Olfactory dysfunction (OD) appeared before the other symptoms in 11.8% of cases. The sQO-NS scores were significantly lower in patients with anosmia compared with normosmic or hyposmic individuals (p = 0.001). Among the 18.2% of patients without nasal obstruction or rhinorrhea, 79.7% were hyposmic or anosmic. The early olfactory recovery rate was 44.0%. Females were significantly more affected by olfactory and gustatory dysfunctions than males (p = 0.001).

CONCLUSION

Olfactory and gustatory disorders are prevalent symptoms in European COVID-19 patients, who may not have nasal symptoms. The sudden anosmia or ageusia need to be recognized by the international scientific community as important symptoms of the COVID-19 infection.