Alpha-lipoic acid does not improve olfactory training results in olfactory loss due to COVID-19: a double-blind randomized trial

Abstract Objectives Olfactory loss is a recognized long-term dysfunction after Coronavirus Disease 2019 (COVID-19) infection. This investigation aimed to assess the effect of alpha-lipoic acid as an adjuvant treatment of olfactory training on the improvement of smell loss in post-COVID-19 patients. Methods This randomized controlled trial included 128 adult outpatients who had persistent smell loss for more than 3-months after COVID-19 infection. The participants were randomly allocated into two groups: the intervention treatment group, which received alpha-lipoic acid associated to olfactory training, and comparison treatment group, which received placebo pills associated to olfactory training. The participants were followed-up for 12-weeks. Olfactory dysfunction was assessed in terms of Visual Analog Scale (VAS), and the Connecticut Chemosensory Clinical Research Center (CCCRC) test for the Brazilian population. Results A total of 100 participants completed the follow-up period and were analyzed in this study. Both groups have improved CCCRC score (p= 0.000), olfactory threshold (p= 0.000), identification score (p= 0.000) and VAS score (p= 0.000) after 12-weeks follow-up. No significant differences were determined between the intervention and comparison treatment groups in CCCRC score (p= 0.63), olfactory threshold (p= 0.50), identification score (p= 0.96) and VAS score (p= 0.97). In all these criteria, comparison treatment group went slightly worse. At the endpoint of the study, the frequency of anosmia reduced to 2% in the intervention treatment group and to 7.8% in the comparison treatment group. Also, 16.8% of the intervention group' subjects, and 15.7% of comparison treatment group's patients reached normosmia. Conclusions Overall, there was a strongly significant difference in olfactory function between baseline and endpoint for both groups. However, based on the lack of significant difference between the intervention treatment and the comparison treatment groups in terms of olfactory changes, our study appoints that the alpha-lipoic acid is not better than olfactory training alone to treat olfactory loss after COVID-19. Level of evidence Level 2.

Olfactory Performance among Hospital Residents

Abstract Introduction Smell plays an important role in the maintenance of health and quality of life of the general population. Health workers with olfactory impairment may not be able to help diagnose certain diseases, and subsequently increase the risk of hazardous events and mortality among those affected. 'Odor learning' requires repeated experiences with different smells to develop a discriminatory ability, and this is a process that takes years. Because of that, physicians of certain medical specialities have better odor detection than others. Objective To study the olfactory performance and associated factors of otorhinolaryngology residents compared with residents of different medical specialities in a representative sample of a tertiary hospital. Methods The University of Pennsylvania Smell Identification Test (UPSIT) was used to compare olfactory performance. Clinical and epidemiological data were collected among 42 hospital residents. Results Otorhinolaryngology residents presented an average UPSITscore of 35.0, and the other residents, a score of 32.8 (p = 0.02) Of all the residents, 40.5% showed some grade of olfactory impairment. Half of the females students in the first year of residency showed olfactory dysfunction. The multivariate analyses found age (p = 0.03; 95% confidence interval for β = 0.33) to be an independent predictor of the UPSIT score. Conclusion The present study demonstrated that otorhinolaryngology residents have greater olfactory capacity compared with other residents. Future studies should explore the relevant factors of olfactory impairment and its impact on quality of life in this population.

Diagnóstico en la patología del olfato: revisión de la literatura / Diagnosis in smell pathology: literature review

La patología del olfato es una afección común en la población, principalmente en adultos mayores, que puede alterar de manera significativa la calidad de vida del paciente, pudiendo ser la manifestación inicial de enfermedades neurológicas como la enfermedad de Parkinson. A pesar de su relevancia, el sentido del olfato continúa siendo poco estudiado en clínica, no obstante la existencia de métodos simples validados para su evaluación. En este articulo realizamos una revisión y análisis de la literatura actual sobre el estudio clínico del olfato, con el objetivo de establecer las herramientas diagnósticas disponibles en la práctica clínica para su estudio.

Olfactory diseases are common to find in the population, mainly in older people, and it can affect significantly life quality. It can also be the first manifestation of neurological diseases, such as Parkinson disease. Despite its relevance, the sense of smell is still not studied although there are simple and validated methods available in the clinical practice. In this article, we make a review and analysis of the actual literature related to smell studies, so that we can establish available diagnosis tools in the clinical practice.

Olfactory Identification Test Using Familiar Distracters for Koreans

OBJECTIVES: Odors used in an odor identification test should be familiar to the subject, but there are some unfamiliar distracters in Korean version of Sniffin' stick (KVSS) II identification test. In this study, we used the results of the original version of KVSS II identification to modify the KVSS II identification test. METHODS: Eighty-three participants took an original version of KVSS II identification test and a visual analogue scale of subjective odor function. KVSS II identification which has 16 items was performed to choose one out of four odors items. And visual analogue scale was checked from 0 to 10 points of their subjective olfactory function. Two weeks later they took the modified version of KVSS II identification test. Hyposmic or anosmic patients were excluded. RESULTS: The mean score of the original version of KVSS II identification and modified version of KVSS II identification were 11.3 and 12.5, respectively (P<0.05). The KVSS II identification test and subjective olfactory function were positively correlated (r=0.247, P<0.05), as were the modified KVSS II identification test and subjective olfactory function (r=0.329, P<0.05). CONCLUSION: After modification of distracters, KVSS II identification test appears to be suited for assessment of olfactory function.

Applying a new version of the Brazilian-Portuguese UPSIT smell test in Brazil / Aplicando uma nova versão brasileira do UPSIT no Brasil

Standardized olfactory tests are now available to quantitatively assess disorders of olfaction. A Brazilian-Portuguese version of the University of Pennsylvania Smell Identification Test (UPSIT) is currently being developed specifically for the Brazilian population. The most recent Brazilian-Portuguese version of the UPSIT (UPSIT-Br2) was administered to 88 Brazilian subjects who had no history of neurological or otorhinolaryngological disease. UPSIT-Br2 scores decreased with age, were lower in men than in women, and were lower in subjects with lower income. The degree to which the poorer performance of subjects with lower socio-economic status reflects lack of familiarity with test items is not known. Although this version of the UPSIT provides a sensitive and useful test of smell function for the Brazilian population, a revision of some test items is needed to achieve comparable norms to those found using the North American UPSIT in the United States.

Testes padronizados já estão disponíveis para testagem do olfato e uma versão em Português esta sendo desenvolvida para o University of Pennsylvania Smell Identification Test (UPSIT), especificamente para a população brasileira. A versão mais recente deste teste (chamada UPSIT-Br2) foi aplicada a 88 sujeitos brasileiros que não tinham história de qualquer problema neurológico ou otorrinolaringológico. Compatível com dados prévios da literatura, a performance no UPSIT-Br2 decaiu com a idade e foi inferior no genero masculino. Os resultados foram mais baixos em participantes de menor nível sócio-econômico e a relação deste achado com a falta de familiaridade para com os itens do teste não é conhecida. Apesar desta versão do UPSIT poder ser útil para o teste da função olfativa da população brasileira, a revisão de alguns itens se faz necessária para alcançar valores comparáveis aos dados normativos norte-americanos.