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

Neurocognitive Changes in Patients with Post-COVID Depression

Background: Depression and cognitive impairment are recognized complications of COVID-19. This study aimed to assess cognitive performance in clinically diagnosed post-COVID depression (PCD, n = 25) patients using neuropsychological testing. Methods: The study involved 71 post-COVID patients with matched control groups: recovered COVID-19 individuals without complications (n = 18) and individuals without prior COVID-19 history (n = 19). A post-COVID depression group (PCD, n = 25) was identified based on psychiatric diagnosis, and a comparison group (noPCD, n = 46) included participants with neurological COVID-19 complications, excluding clinical depression. Results: The PCD patients showed gender-dependent significant cognitive impairment in the MoCA, Word Memory Test (WMT), Stroop task (SCWT), and Trail Making Test (TMT) compared to the controls and noPCD patients. Men with PCD showed worse performances on the SCWT, in MoCA attention score, and on the WMT (immediate and delayed word recall), while women with PCD showed a decline in MoCA total score, an increased processing time with less errors on the TMT, and worse immediate recall. No differences between groups in Sniffin's stick test were found. Conclusions: COVID-related direct (post-COVID symptoms) and depression-mediated (depression itself, male sex, and severity of COVID-19) predictors of decline in memory and information processing speed were identified. Our findings may help to personalize the treatment of depression, taking a patient's gender and severity of previous COVID-19 disease into account.

Diagnostic accuracy of the screenings Sniffin' Sticks Test (SST-12) in COVID-19 induced olfactory disorders

Objective olfactory function can be assessed using validated olfactory tests like the Sniffin' Sticks Test (SST). However, their extensive nature makes them less suitable for clinical practice. To address this, shorter olfactory tests like the screenings Sniffin' Sticks Test (SST-12) can be used for screening purposes and reduce testing time. The SST-12 serves as a diagnostic tool for screening olfaction in cases unrelated to COVID-19. However, these screening tests are uncertain regarding their accuracy in detecting olfactory dysfunction in patients with COVID-19 as the plausible cause. We aim to determine the diagnostic accuracy of the SST-12 in adults with post-COVID-19 olfactory dysfunction. We performed a diagnostic accuracy study with data from 113 consecutive COVID-19 diagnosed patients who experienced objectified smell loss ever since. At approximately 6 months after their diagnosis, all participants underwent the SST (reference standard), part of the SST was the SST-12 (index test). Diagnostic accuracy of the SST-12 is measured as negative predictive value (NPV), positive predictive value (PPV), sensitivity, and specificity. The SST-12 detected smell loss in 85 patients among 91 patients with smell loss and ruled out smell loss in 15 patients among the 22 patients without smell loss based on the reference standard. Making sensitivity 93.4% (CI 0.87-0.97), and specificity 68.2% (CI 0.48-0.85). Out of the 92 patients with a positive test result on SST-12, 85 patients had indeed smell loss (PPV 92.4% CI 0.86-0.97), and out of the 21 patients with a negative test result, 15 patients had no smell loss regarding the reference standard (NPV 71.4% CI 0.50-0.88). The findings suggest that the SST-12 holds promise as a useful tool for identifying individuals with smell loss, also in individuals with COVID-19 as cause, but it is important to have a good understanding of the interpretation of the results of the SST-12 when considering its implementation in clinical practice.

Persistent post-COVID-19 dysosmia: Practices survey of members of the French National Union of Otorhinolaryngology-Head and Neck Surgery Specialists. CROSS analysis

INTRODUCTION

Persistent dysosmia more than 3 months after SARS-CoV-2 disease (COVID-19) is considered as long-COVID olfactory disease (LCOD). The primary objective of this study was to evaluate the diagnostic and therapeutic management of LCOD in the daily clinical practice of members of the National Union of Otorhinolaryngology-Head and Neck Surgery Specialists (Syndicat national des médecins spécialisés en ORL et chirurgie cervico-faciale) (SNORL). The secondary objective was to identify factors influencing management within the descriptive survey data.

MATERIALS AND METHODS

A questionnaire was designed (GoogleForm®) and e-mailed to all 715 SNORL members in January 2022.

RESULTS

The response rate was 7.4% (n=53/715). In total, 94.3% of respondents (n=50) had managed LCOD cases, and 56% (n=28) used psychophysical olfactory tests. Specific olfactory medical therapy involved local corticosteroid nasal sprays in 49.1% of cases (n=26) and oral corticosteroids in 32.1% (n=17). Olfactory self-training was prescribed by 81.1% of respondents, with associated speech pathologist therapy in 15.1% (n=8) of cases. No predictive factors for specific management were identified.

CONCLUSION

Olfactometry is currently under-applied. Consistent with guidelines, non-drug therapy (olfactory training) is the first-line treatment for LCOD.

A quick test to objectify smell and taste dysfunction at home: a proof of concept for the validation of the chemosensory perception test

Recent studies have shown the efficacy of a home test for the self-evaluation of olfactory and gustatory functions in quarantined coronavirus disease-2019 (COVID-19) patients. However, testing was often limited to COVID-19 participants, and the accuracy of home test kits was rarely compared to standardized testing. This study aims at providing proof of concept for the validation of the new Chemosensory Perception Test (CPT) developed to remotely assess orthonasal olfactory, retronasal olfactory, and gustatory functions in various populations using common North American household items. In the 2 experiments, a total of 121 participants irrespective of having olfactory and/or gustatory complaints from various causes (COVID-19, sinunasal, post-viral, idiopathic) were tested first, with one or many of the following tests: (i) a brief chemosensory questionnaire, (ii) an olfactory test-Sniffin' Sticks Test (SST) or University of Pennsylvania Smell Identification Test (UPSIT), and/or (iii) a gustatory test-Brief Waterless Empirical Taste Test (B-WETT). We then applied the CPT which yielded 3 different subscores, namely orthonasal, retronasal, and gustatory CPT scores. The orthonasal CPT score was significantly correlated with SST (ρ = 0.837, P < 0.001) and UPSIT (ρ = 0.364, P < 0.001) scores, and exhibited an excellent accuracy to identify olfactory dysfunction (OD) as compared to SST (area under the curve [AUC]: 0.923 [95% confidence interval {CI}, 0.822-1.000], P < 0.001). The retronasal CPT score but not the gustatory CPT score allowed to distinguish between participants with or without subjective gustatory complaint (AUC: 0.818 [95% CI, 0.726-0.909], P < 0.001). The CPT has the ability to identify OD and to quantify subjective gustatory complaints.

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

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

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.

Long-Lasting Olfactory Dysfunction in Hospital Workers Due to COVID-19: Prevalence, Clinical Characteristics, and Most Affected Odorants

Hospital workers have increased exposure risk of healthcare-associated infections due to the frontline nature of their work. Olfactory dysfunction is highly prevalent. The objectives for this investigation are to study the prevalence of long-lasting olfactory dysfunction associated with COVID-19 infection in hospital workers during the first pandemic wave, to identify clinical characteristics and associated symptomatology, and to analyze how many patients with COVID-19 infection had developed olfactory dysfunction during infection and maintained a reduced olfactory function for approximately 10 weeks after diagnosis. Between June and July of 2020, a cross-sectional study was carried out at the Hospital Central de la Cruz Roja San José and Santa Adela in Madrid, Spain. One hundred sixty-four participants were included, of which 110 were patient-facing healthcare staff and 54 were non-patient-facing healthcare staff. Participants were split into three groups, according to COVID-19 diagnosis and presence of COVID-19 related olfactory symptomatology. Participants were asked to complete a structured online questionnaire along with Sniffin' Stick Olfactory Test measurements. In this study, 88 participants were confirmed for COVID-19 infection, 59 of those participants also reported olfactory symptomatology. The prevalence of COVID-19 infection was 11.35%, and the prevalence for olfactory dysfunction was 67.05%. Olfactory dysfunction associated with COVID-19 infection leads to long-lasting olfactory loss. Objective assessment with Sniffin' Stick Olfactory Test points to odor identification as the most affected process. Lemon, liquorice, solvent, and rose are the odors that are worst recognized. Mint, banana, solvent, garlic, coffee, and pineapple, although they are identified, are perceived with less intensity. The findings of this study confirmed a high prevalence of SARS-CoV-2 infection among the hospital workers.

Olfactory Dysfunction in COVID-19 Patients Who Do Not Report Olfactory Symptoms: A Pilot Study with Some Suggestions for Dentists

BACKGROUND

Smell and taste dysfunction are frequently reported by SARS-CoV-2 positive patients. The degree of olfactory and gustatory dysfunction varies from a very mild reduction to their complete loss. Several studies have been performed to determine their prevalence in COVID-19 patients, mostly using subjective measurement methods. The literature lacks long-term studies regarding duration and recovery.

METHODS

We assessed olfactory performance, using the Sniffin' Sticks olfactory test, in a group of patients who had not reported olfactory dysfunction, around 131 days after their COVID-19 diagnosis.

RESULTS

11 out of 20 subjects showed no olfactory reduction (65%), while 9 subjects showed reduced TDI score (45%). A total of 13 subjects (65%) scored above the cutoff point for Threshold, 16 subjects (80%) scored above the cutoff point for discrimination and 13 subjects (65%) scored above the cutoff point for identification.

CONCLUSION

Objective measurement methods of olfactory performance show a higher prevalence of olfactory reduction compared to patients' self-reported questionnaires. Olfactory dysfunction can last even months after its onset and because of its high prevalence, it could be a screening symptom for suspect COVID-19 cases.