ArticleJournal of internal medicine2021
Prevalence and 6-month recovery of olfactory dysfunction: a multicentre study of 1363 COVID-19 patients.
Article in Journal of internal medicine, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to 2 registered trials, which are not on this map. Cited by 121 papers, 8 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Fluvoxamine to Augment Olfactory Recovery For Long COVID-19 Parosmia (FluCOP Trial)
A Single-Arm Study to Evaluate the Feasibility of CYR-064 Theophylline Nasal Spray for the Treatment of Parkinson's Disease Related Hyposmia and Anosmia
Who cites it
121 citing papers in PubMed, 8 syntheses or guidelines pooled it.
- The assessment of qualitative olfactory dysfunction in COVID-19 patients: a systematic review of tools and their content validity.Frontiers in psychology · 2023Pooled it
- Taste loss as a distinct symptom of COVID-19: a systematic review and meta-analysis.Chemical senses · 2023Pooled it
- COVID-19 disease severity to predict persistent symptoms: a systematic review and meta-analysis.Primary health care research & development · 2022Pooled it
- Long COVID, audiovestibular symptoms and persistent chemosensory dysfunction: a systematic review of the current evidence.Acta otorhinolaryngologica Italica : organo ufficiale della Societa italiana di otorinolaringologia e chirurgia cervico-facciale · 2022Pooled it
- The prevalence of sensory changes in post-COVID syndrome: A systematic review and meta-analysis.Frontiers in medicine · 2022Pooled it
- Frequency of Neurologic Manifestations in COVID-19: A Systematic Review and Meta-analysis.Neurology · 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
- Pooled it
- Cognitive assessment of patients with post-COVID olfactory dysfunction and impaired domains.Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology · 2026Article
- Unique and shared patterns of chemosensory dysfunction distinguish chronic COVID-19 and aspirin-exacerbated respiratory disease.Annals of allergy, asthma & immunology : official publication of the American College of Allergy, Asthma, & Immunology · 2026Article
- Quality of Life and Chemosensory Function in Post-COVID Patients: Adherence to Olfactory Training.The Annals of otology, rhinology, and laryngology · 2026Article
- FAK inhibition following acute olfactory epithelial inflammation promotes neurogenesis and functional recovery through stem cell CNTF.Stem cells (Dayton, Ohio) · 2026Article
- Evaluating methods for quantitative olfactory assessment: a comparative longitudinal analysis of Sniffin' Sticks and alternative tools.Chemical senses · 2026Article
- Combination antiviral and anti-inflammatory therapy mitigates persistent neurological deficits in mice post SARS-CoV-2 infection.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- Functional olfactory impairment and fatigue in post-COVID-19 syndrome including ME/CFS - a longitudinal prospective observational study.Brain, behavior, & immunity - health · 2025Article
- Prevalence and Clinical Factors Associated with Self-reported Smell and Taste Disorders in Older Adults Hospitalized with COVID-19.International archives of otorhinolaryngology · 2025Article
- Viral Etiologies and Histopathological Features of Olfactory Dysfunction: A Systematic Review.Health science reports · 2025Review
- SARS-CoV-2-induced sensory perturbations: A narrative review of clinical phenotypes, molecular pathologies, and possible interventions.Brain, behavior, & immunity - health · 2025Review
- Consensus based recommendations for the management of post-COVID long-term sequelae (Long COVID): a regional perspective.Frontiers in medicine · 2025Article
- White matter changes in recovered COVID-19 patients: insights from DTI, DKI, and NODDI metrics.Frontiers in neurology · 2025Article
61 more citing papers are in PubMed but not listed here.
Corrections and comments
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Authors and funding
13 authors.
Funding
Abstract
objectiveTo investigate prevalence and recovery of olfactory dysfunction (OD) in COVID-19 patients according to the disease severity.
methodsFrom 22 March to 3 June 2020, 2581 COVID-19 patients were identified from 18 European hospitals. Epidemiological and clinical data were extracted at baseline and within the 2-month post-infection.
resultsThe prevalence of OD was significantly higher in mild form (85.9%) compared with moderate-to-critical forms (4.5-6.9%; P = 0.001). Of the 1916 patients with OD, 1363 completed the evaluations (71.1%). A total of 328 patients (24.1%) did not subjectively recover olfaction 60 days after the onset of the dysfunction. The mean duration of self-reported OD was 21.6 ± 17.9 days. Objective olfactory evaluations identified hyposmia/anosmia in 54.7% and 36.6% of mild and moderate-to-critical forms, respectively (P = 0.001). At 60 days and 6 months, 15.3% and 4.7% of anosmic/hyposmic patients did not objectively recover olfaction, respectively. The higher baseline severity of objective olfactory evaluations was strongly predictive of persistent OD (P < 0.001).
conclusionOD is more prevalent in mild COVID-19 forms than in moderate-to-critical forms. OD disappeared in 95% of patients regarding objective olfactory evaluations at 6 months.
Indexed as
Identifiers
33403772What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.