Orji Foster Tochukwu, Akpeh James O, Okolugbo Nekwu E
Department of Otolaryngology, University of Nigeria Nsukka, Enugu, Nigeria.
University of Nigeria Teaching Hospital, Enugu, Nigeria.
Indian J Otolaryngol Head Neck Surg. 2023 Dec;75(4):4179-4189. doi: 10.1007/s12070-023-04005-8. Epub 2023 Jul 3.
Recently acquired olfactory dysfunction (OD) has emerged as one of hallmark manifestations of the novel Corona virus disease (COVID-19), but the evolution of its spontaneous recovery has remained inconclusive, with reports of persistence of OD beyond six months of onset. We undertook this systematic review and meta-analysis with a view to generating a pooled recovery rate of COVID-19 associated olfactory dysfunctions and attempt to examine the predictors of olfactory recovery. Systematic review and meta-analysis. A systematic search of Scopus, Google Scholar, and PubMed data bases, comprising all longitudinal studies reporting the trajectory of COVID-19 related OD was carried out. The pooled recovery rate was estimated with random-effects model, and the potential heterogeneity of the subgroup sources was analyzed using meta-regression test. After the PRISMA selection process 28 studies from 16 countries were included, with a total of 5,175 OD patients, among 11,948 COVID-19 cases. The estimated global pooled recovery rate of OD was 82.7% (95% CI, 77.46%-88.04%), with a pooled median duration of OD of 11.6 days. Only 2 out of 28 studies had recovery data beyond a period of 2 months. But no significant difference was found in the recovery rate regarding the length of follow up ( = 0.840). Studies that conducted objective olfactory assessments showed significant higher recovery rate than those with subjective assessments ( = 0.001). Although ten studies (36%) reported > 90% recovery, nine studies (32%) documented persistence of OD in > 25% of their patients. Five out of 6 studies showed that hyposmia tended to show complete recovery than anosmia. Age, co-morbidities, and intra-nasal treatments had no effects. Test of homogeneity between subgroups using the Cochran's Q test was not significant (Q = 0.69, = 0.40). Our meta-analysis revealed high rate of early and medium term recovery of COVID-19 related OD. However, it also showed disturbing rates of persistence of OD. Anosmia tended to be predictive of residual OD than hyposmia. Age, co-morbidities, intra-nasal corticosteroid and decongestants, had no effects on OD recovery.
近期获得性嗅觉功能障碍（OD）已成为新型冠状病毒病（COVID-19）的标志性表现之一，但其自发恢复的演变情况尚无定论，有报告称发病六个月后嗅觉功能障碍仍持续存在。我们进行了这项系统评价和荟萃分析，旨在得出COVID-19相关嗅觉功能障碍的综合恢复率，并尝试研究嗅觉恢复的预测因素。系统评价和荟萃分析。对Scopus、谷歌学术和PubMed数据库进行了系统检索，纳入所有报告COVID-19相关嗅觉功能障碍病程的纵向研究。采用随机效应模型估计综合恢复率，并使用荟萃回归检验分析亚组来源的潜在异质性。经过PRISMA筛选过程，纳入了来自16个国家的28项研究，在11948例COVID-19病例中共有5175例嗅觉功能障碍患者。估计嗅觉功能障碍的全球综合恢复率为82.7%（95%CI，77.46%-88.04%），嗅觉功能障碍的综合中位持续时间为11.6天。28项研究中只有2项有超过2个月的恢复数据。但随访时间长短对恢复率没有显著差异（P = 0.840）。进行客观嗅觉评估的研究显示恢复率显著高于主观评估的研究（P = 0.001）。尽管有10项研究（36%）报告恢复率>90%，但有9项研究（32%）记录了超过25%的患者嗅觉功能障碍持续存在。6项研究中有5项表明，嗅觉减退比嗅觉丧失更倾向于完全恢复。年龄、合并症和鼻内治疗没有影响。使用 Cochr an's Q检验对亚组间的同质性检验不显著（Q = 0.69，P = 0.40）。我们的荟萃分析显示，COVID-19相关嗅觉功能障碍的早期和中期恢复率较高。然而，它也显示出令人不安的嗅觉功能障碍持续率。与嗅觉减退相比，嗅觉丧失更倾向于预测残留的嗅觉功能障碍。年龄、合并症、鼻内皮质类固醇和减充血剂对嗅觉功能障碍的恢复没有影响。
