Bacon Daniel R, Onuorah Princess, Murr Alexander, Wiesen Christopher A, Oakes Jonathan, Thorp Brian D, Zanation Adam M, Ebert Charles S, Wohl David, Senior Brent A, Kimple Adam J
Department of Otolaryngology/Head & Neck Surgery, University of North Carolina Chapel Hill, Chapel Hill, NC.
Odum Institute - University of North Carolina at Chapel Hill, Chapel Hill, NC.
Rhinol Online. 2021;4(4):131-139. doi: 10.4193/rhinol/21.034. Epub 2021 Aug 13.
Evidence regarding prevalence of COVID-19 related Olfactory dysfunction (OD) among ambulatory patients is highly variable due to heterogeneity in study population and measurement methods. Relatively few studies have longitudinally investigated OD in ambulatory patients with objective methods.
We performed a longitudinal study to investigate OD among COVID-19 ambulatory patients compared to symptomatic controls who test negative. Out of 81 patients enrolled, 45 COVID-19 positive patients and an age- and sex-matched symptomatic control group completed the BSIT and a questionnaire about smell, taste and nasal symptoms. These were repeated at 1 month for all COVID-19 positive patients, and again at 3 months for those who exhibited persistent OD. Analysis was performed by mixed-effects linear and logistic regression.
46.7% of COVID-19 patients compared to 3.8% of symptomatic controls exhibited OD at 1-week post diagnosis (p<0.001). At 1 month, 16.7%, (6 of 36), of COVID-19 patients had persistent OD. Mean improvement in BSIT score in COVID-19 patients between 1-week BSIT and 1 month follow-up was 2.0 (95% CI 1.00 - 3.00, p<0.001). OD did not correlate with nasal congestion (r= -0.25, 95% CI, -0.52 to 0.06, p=0.12).
Ambulatory COVID-19 patients exhibited OD significantly more frequently than symptomatic controls. Most patients regained normal olfaction by 1 month. The BSIT is a simple validated and objective test to investigate the prevalence of OD in ambulatory patients. OD did not correlate with nasal congestion which suggests a congestion-independent mechanism of OD.
由于研究人群和测量方法的异质性，关于门诊患者中与新冠病毒相关嗅觉功能障碍（OD）患病率的证据差异很大。相对较少的研究采用客观方法对门诊患者的OD进行纵向调查。
我们进行了一项纵向研究，以调查新冠病毒门诊患者与检测呈阴性的有症状对照者之间的OD情况。在纳入的81名患者中，45名新冠病毒阳性患者和一个年龄及性别匹配的有症状对照组完成了嗅觉脑干诱发电位测试（BSIT）以及一份关于嗅觉、味觉和鼻部症状的问卷。所有新冠病毒阳性患者在1个月时重复进行这些测试，对于表现出持续性OD的患者，在3个月时再次重复测试。通过混合效应线性和逻辑回归进行分析。
与3.8%的有症状对照者相比，46.7%的新冠病毒患者在诊断后1周出现OD（p<0.001）。在1个月时，16.7%（36例中的6例）的新冠病毒患者存在持续性OD。新冠病毒患者在1周BSIT和1个月随访之间，BSIT评分的平均改善为2.0（95%可信区间1.00 - 3.00，p<0.001）。OD与鼻塞无关（r = -0.25，95%可信区间，-0.52至0.06，p = 0.12）。
新冠病毒门诊患者出现OD的频率明显高于有症状对照者。大多数患者在1个月时恢复了正常嗅觉。BSIT是一种简单、经过验证的客观测试，可用于调查门诊患者中OD的患病率。OD与鼻塞无关，这表明存在一种与鼻塞无关的OD机制。
