Department of Otorhinolaryngology, Head and Neck Surgery, Vienna General Hospital, Medical University of Vienna, 1090, Vienna, Austria.
Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany.
Eur Arch Otorhinolaryngol. 2022 Jan;279(1):257-265. doi: 10.1007/s00405-021-06826-1. Epub 2021 May 13.
Olfactory dysfunction (OD) constitutes a major symptom in Coronavirus Disease 2019 (COVID-19). Yet, most data on smell loss rely on the evaluation of orthonasal olfactory performance. Therefore, we aimed to assess retronasal olfactory function (ROF) over a period of several weeks in proven and suspected COVID-19 patients.
One hundred and one subjects with suspected or laboratory-proven COVID-19 participated in this study. In patients with OD no longer than 4 weeks after initial symptom onset, ROF was measured with the 7-item Candy Smell Test ten times over 7 weeks.
Olfactory function was decreased in the investigated patients and remained decreased over the course of 7 weeks. One-way repeated-measures ANOVA revealed no significant difference of ROF between different measurement time points. However, self-assessment of smell and flavour improved significantly (p = 0.013 and p = 0.043), but did not show complete recovery.
The current investigation revealed significant improvements in subjective smell and flavour perception over the course of 7 weeks in proven and suspected COVID-19 patients suffering from acute OD. However, objectively measured ROF based on a screening test revealed no improvements within the same time period.
嗅觉功能障碍（OD）是 2019 年冠状病毒病（COVID-19）的主要症状之一。然而，大多数关于嗅觉丧失的数据依赖于对鼻前嗅觉性能的评估。因此，我们旨在评估确诊和疑似 COVID-19 患者在数周内的逆行嗅觉功能（ROF）。
101 名疑似或实验室确诊 COVID-19 的患者参与了这项研究。在最初症状出现后 OD 持续时间不超过 4 周的患者中，使用 7 项糖果嗅觉测试（Candy Smell Test）在 7 周内进行 10 次 ROF 测量。
调查患者的嗅觉功能下降，并且在 7 周的过程中持续下降。单因素重复测量方差分析显示，ROF 在不同测量时间点之间无显著差异。然而，嗅觉和味觉的自我评估显著改善（p=0.013 和 p=0.043），但并未完全恢复。
本研究显示，在确诊和疑似 COVID-19 患者中，急性 OD 患者在 7 周的时间内主观嗅觉和味觉感知显著改善。然而，在同一时期内，基于筛选测试的客观测量 ROF 没有改善。
