SynthesisThe American journal of the medical sciences2021
The Association of "Loss of Smell" to COVID-19: A Systematic Review and Meta-Analysis.
Synthesis in The American journal of the medical sciences, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 44 papers, 6 of them syntheses that pooled it.
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Who cites it
44 citing papers in PubMed, 6 syntheses or guidelines pooled it.
- Clinical features of COVID-19 for integration of COVID-19 into influenza surveillance: A systematic review.Journal of global health · 2022Pooled it
- Systematic review and meta-analysis of olfactory and gustatory dysfunction in COVID-19.International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases · 2022Pooled it
- The D614G Virus Mutation Enhances Anosmia in COVID-19 Patients: Evidence from a Systematic Review and Meta-analysis of Studies from South Asia.ACS chemical neuroscience · 2021Pooled it
- Is loss of smell an early predictor of COVID-19 severity: a systematic review and meta-analysis.Archives of pharmacal research · 2021Pooled it
- The Proportion of SARS-CoV-2 Infections That Are Asymptomatic : A Systematic Review.Annals of internal medicine · 2021Pooled it
- Characteristics of Viral Shedding Time in SARS-CoV-2 Infections: A Systematic Review and Meta-Analysis.Frontiers in public health · 2021Pooled it
- Effectiveness of platelet-rich plasma on post-COVID chronic olfactory dysfunction.Revista da Associacao Medica Brasileira (1992) · 2023Trial
- A quantitative metabolic signature of host response during SARS-CoV-2 infection and recovery.iScience · 2026Article
- Inflammatory Markers as Predictors of Onset and Recovery of Olfactory and Gustatory Dysfunction in COVID-19 Patients.Cureus · 2025Article
- Synthetic Cadaver Odorants and the Sulfur Gap: Linking Chemistry and Canine Olfaction in Human Remains Detection.Molecules (Basel, Switzerland) · 2025Review
- Article
- Predicting Intensive Care Unit Admission in COVID-19-Infected Pregnant Women Using Machine Learning.Journal of clinical medicine · 2024Article
- Review
- Article
- Article
- Understanding the Prevalence and Risk Factor Profile of Olfactory Impairment and Its Impact on Patient Health Indicators and Economic Outcomes in Community-Dwelling Older Asian Adults.Innovation in aging · 2024Article
- Olfactory dysfunction among patients with COVID-19.Saudi medical journal · 2023Article
- Prevalence of Self-Reported Anosmia and Ageusia in Elderly Patients Who Had Been Previously Hospitalized by SARS-CoV-2: The LONG-COVID-EXP Multicenter Study.Journal of clinical medicine · 2023Article
- Aberrant olfactory network functional connectivity in people with olfactory dysfunction following COVID-19 infection: an exploratory, observational study.EClinicalMedicine · 2023Article
- Analysis of Symptom Spectra and Associated Factors Among 536 Respondents During the COVID-19 Epidemic in China: A Cross-Sectional Study.Journal of multidisciplinary healthcare · 2023Article
Corrections and comments
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Authors and funding
6 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe presence of olfactory dysfunction or "loss of smell" has been reported as an atypical symptom in patients with coronavirus disease 2019 (COVID-19). We performed a systematic review and meta-analysis of the available literature to evaluate the prevalence of "loss of smell" in COVID-19 as well as its utility for prognosticating the disease severity.
methodsAn exhaustive search of the PubMed/Medline, Embase, Web of Science, Cochrane Library, LitCovid NIH, and WHO COVID-19 database was conducted through August 6
resultsA total of 51 studies with 11074 confirmed COVID-19 patients were included. Of these, 21 studies used a control group with 3425 patients. The symptom of "loss of smell" (OR: 14.7, CI: 8.9-24.3) was significantly higher in the COVID-19 group when compared to the control group. Seven studies comparing severe COVID-19 patients with- and without "loss of smell" demonstrated favorable prognosis for patients with "loss of smell" (OR: 0.36, CI 0.27-0.48).
conclusionsOlfactory dysfunction or "loss of smell" is a prevalent symptom in COVID-19 patients. Moreover, COVID-19 patients with "loss of smell" appear to have a milder course of the disease.
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