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Tervo JP, Jacobson PT, Vilarello BJ, Saak TM, Caruana FF, Gallagher LW, Gary JB, Gudis DA, Joseph PV, Devanand D, Goldberg TE, Overdevest JB. Recovery rates of persistent post-COVID-19 olfactory dysfunction using psychophysical assessment: A longitudinal cohort study. World J Otorhinolaryngol Head Neck Surg 2024; 10:79-87. [PMID: 38855287 PMCID: PMC11156685 DOI: 10.1002/wjo2.179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 02/21/2024] [Accepted: 03/08/2024] [Indexed: 06/11/2024] Open
Abstract
Objectives Persistent olfactory dysfunction (OD) following loss of smell associated with SARS-CoV-2 infection is a major feature of long COVID. Perspectives on the prevalence of persistent OD predominantly rely on self-reported olfactory function. Few studies have tracked longitudinal rates of recovery using psychophysical assessment among patients presenting for evaluation of persistent OD beyond a window of acute recovery. Data anchored in standardized testing methods are needed to counsel patients who fail to acutely regain their sense of smell. This study aims to quantify the degree of persistent OD in post-COVID-19 patients who experience subjective and psychophysical OD. Methods We grouped participants presenting for OD evaluation into cohorts based on both subjective and psychophysical olfactory status at a baseline assessment and assessed their olfactory abilities with a visual analogue scale and the Sniffin' Sticks extended test at baseline and 1-year time points. Participants had confirmed a history of COVID-19 by lab evaluation or clinical diagnosis if lab evaluation was not available. Results Baseline olfactory evaluation was completed by 122 participants, 53 of whom completed the 1-year follow-up assessment. Among participants presenting with perceived OD, 74.5% had confirmed psychophysical OD at baseline, with 55.1% at 1-year follow-up. Participants had reliable trends in self-rated versus psychophysically tested olfactory function at both time points. The total threshold, discrimination, and identification (TDI) score improved by +3.25 points in the cohort with psychophysical OD (p = 0.0005), with this improvement largely attributable to an increase in median threshold scores (+2.75 points; p = 0.0004). Conclusions OD persists in a significant number of patients who fail to acutely recovery their sense of smell after COVID-19, with many demonstrating lingering deficits at 1-year. Improvements in threshold, but not discrimination or identification, most significantly mediate improvement of total TDI score at follow-up.
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Affiliation(s)
- Jeremy P. Tervo
- Columbia University Vagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
| | - Patricia T. Jacobson
- Department of Otolaryngology‐Head and Neck SurgeryNew York‐Presbyterian/Columbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Brandon J. Vilarello
- Columbia University Vagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
| | - Tiana M. Saak
- Columbia University Vagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
| | - Francesco F. Caruana
- Department of Otolaryngology‐Head and Neck SurgeryUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - Liam W. Gallagher
- Department of Otolaryngology‐Head and Neck SurgeryUniversity of MinnesotaMinneapolisMinnesotaUSA
| | - Joseph B. Gary
- Columbia University Vagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
| | - David A. Gudis
- Columbia University Vagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
- Department of Otolaryngology‐Head and Neck SurgeryNew York‐Presbyterian/Columbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Paule V. Joseph
- National Institute of Alcohol Abuse and Alcoholism, Section of Sensory Science and Metabolism & National Institute of Nursing ResearchBethesdaMarylandUSA
| | - D.P. Devanand
- Columbia University Vagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
- Department of PsychiatryNew York‐Presbyterian/Columbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Terry E. Goldberg
- Department of PsychiatryNew York‐Presbyterian/Columbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Jonathan B. Overdevest
- Columbia University Vagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
- Department of Otolaryngology‐Head and Neck SurgeryNew York‐Presbyterian/Columbia University Irving Medical CenterNew YorkNew YorkUSA
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Sienkiewicz-Oleszkiewicz B, Hummel T. Olfactory function in diabetes mellitus. J Clin Transl Endocrinol 2024; 36:100342. [PMID: 38585386 PMCID: PMC10997837 DOI: 10.1016/j.jcte.2024.100342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 03/18/2024] [Accepted: 03/29/2024] [Indexed: 04/09/2024] Open
Abstract
Diabetes mellitus (DM) is an increasingly common disease in both children and adults. In addition to neuronal and/or vascular disorders, it can cause chemosensory abnormalities including olfactory deterioration. The purpose of this article is to summarize current knowledge on olfactory function in DM, highlighting the impact of co-morbidities, especially obesity, thyroid dysfunction, chronic kidney disease and COVID-19 on olfactory outcomes. Research to date mostly shows that olfactory impairment is more common in people with diabetes than in the general population. In addition, the presence of concomitant diseases is a factor increasing olfactory impairment. Such a correlation was shown for type 1 diabetes, type 2 diabetes and gestational diabetes. At the same time, not only chronic diseases, but also DM in acute conditions such as COVID-19 leads to a higher prevalence of olfactory disorders during infection. Analyzing the existing literature, it is important to be aware of the limitations of published studies. These include the small number of patients studied, the lack of uniformity in the methods used to assess the sense of smell, frequently relying on rated olfactory function only, and the simultaneous analysis of patients with different types of diabetes, often without a clear indication of diabetes type. In addition, the number of available publications is small. Certainly, further research in this area is needed. From a practical point of view decreased olfactory performance may be an indicator for central neuropathy and an indication for assessing the patient's nutritional status, examining cognitive function, especially in older patients and performing additional diagnostic tests, such as checking thyroid function, because all those changes were correlated with smell deterioration.
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Affiliation(s)
- Beata Sienkiewicz-Oleszkiewicz
- Department of Clinical Pharmacology, Faculty of Pharmacy, Wroclaw Medical University, ul. Borowska 211a, 50-556 Wrocław, Poland
- Smell and Taste Clinic, Department of Otorhinolaryngology, Technical University Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Thomas Hummel
- Smell and Taste Clinic, Department of Otorhinolaryngology, Technical University Dresden, Fetscherstr. 74, 01307 Dresden, Germany
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Liu Y, Jia S, Yiu CK, Park W, Chen Z, Nan J, Huang X, Chen H, Li W, Gao Y, Song W, Yokota T, Someya T, Zhao Z, Li Y, Yu X. Intelligent wearable olfactory interface for latency-free mixed reality and fast olfactory enhancement. Nat Commun 2024; 15:4474. [PMID: 38796514 PMCID: PMC11128017 DOI: 10.1038/s41467-024-48884-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 05/14/2024] [Indexed: 05/28/2024] Open
Abstract
Olfaction feedback systems could be utilized to stimulate human emotion, increase alertness, provide clinical therapy, and establish immersive virtual environments. Currently, the reported olfaction feedback technologies still face a host of formidable challenges, including human perceivable delay in odor manipulation, unwieldy dimensions, and limited number of odor supplies. Herein, we report a general strategy to solve these problems, which associates with a wearable, high-performance olfactory interface based on miniaturized odor generators (OGs) with advanced artificial intelligence (AI) algorithms. The OGs serve as the core technology of the intelligent olfactory interface, which exhibit milestone advances in millisecond-level response time, milliwatt-scale power consumption, and the miniaturized size. Empowered by robust AI algorithms, the olfactory interface shows its great potentials in latency-free mixed reality (MR) and fast olfaction enhancement, thereby establishing a bridge between electronics and users for broad applications ranging from entertainment, to education, to medical treatment, and to human machine interfaces.
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Affiliation(s)
- Yiming Liu
- Department of Biomedical Engineering, City University of Hong Kong, Kowloong Tong, Hong Kong, China
- Department of Electrical Engineering and Information systems, The University of Tokyo, Tokyo, 113-8656, Japan
| | - Shengxin Jia
- Department of Biomedical Engineering, City University of Hong Kong, Kowloong Tong, Hong Kong, China
- Hong Kong Center for Cerebra-Cardiovascular Health Engineering, Hong Kong Science Park, New Territories, 999077, Hong Kong, China
| | - Chun Ki Yiu
- Department of Biomedical Engineering, City University of Hong Kong, Kowloong Tong, Hong Kong, China
- Hong Kong Center for Cerebra-Cardiovascular Health Engineering, Hong Kong Science Park, New Territories, 999077, Hong Kong, China
| | - Wooyoung Park
- Department of Biomedical Engineering, City University of Hong Kong, Kowloong Tong, Hong Kong, China
| | - Zhenlin Chen
- Department of Biomedical Engineering, City University of Hong Kong, Kowloong Tong, Hong Kong, China
- Hong Kong Center for Cerebra-Cardiovascular Health Engineering, Hong Kong Science Park, New Territories, 999077, Hong Kong, China
| | - Jin Nan
- Institute of Solid Mechanics, Beihang University, 100191, Beijing, China
| | - Xingcan Huang
- Department of Biomedical Engineering, City University of Hong Kong, Kowloong Tong, Hong Kong, China
| | - Hongting Chen
- Department of Electrical Engineering and Information systems, The University of Tokyo, Tokyo, 113-8656, Japan
| | - Wenyang Li
- Department of Biomedical Engineering, City University of Hong Kong, Kowloong Tong, Hong Kong, China
| | - Yuyu Gao
- Department of Biomedical Engineering, City University of Hong Kong, Kowloong Tong, Hong Kong, China
| | - Weike Song
- China Special Equipment Inspection and Research Institute, 100029, Beijing, China
| | - Tomoyuki Yokota
- Department of Electrical Engineering and Information systems, The University of Tokyo, Tokyo, 113-8656, Japan
- Institution of Engineering Innovation, The University of Tokyo, Tokyo, 113-8656, Japan
| | - Takao Someya
- Department of Electrical Engineering and Information systems, The University of Tokyo, Tokyo, 113-8656, Japan.
- RIKEN Center for Emergent Matter Science (CEMS), Saitama, 351-0198, Japan.
- Thin-film Device Laboratory, RIKEN, Saitama, 351-0198, Japan.
| | - Zhao Zhao
- China Special Equipment Inspection and Research Institute, 100029, Beijing, China.
| | - Yuhang Li
- Institute of Solid Mechanics, Beihang University, 100191, Beijing, China.
- Tianmushan Laboratory, NA, 311115, Hangzhou, China.
- Aircraft and Propulsion Laboratory, Ningbo Institute of Technology Beihang University (BUAA), 315100, Ningbo, China.
- Liaoning Academy of Materials, NA, 110167, Shenyang, China.
| | - Xinge Yu
- Department of Biomedical Engineering, City University of Hong Kong, Kowloong Tong, Hong Kong, China.
- Hong Kong Center for Cerebra-Cardiovascular Health Engineering, Hong Kong Science Park, New Territories, 999077, Hong Kong, China.
- Hong Kong Institute for Clean Energy (HKICE), City University of Hong Kong, Hong Kong, China.
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Pieniak M, Rokosz M, Nawrocka P, Reichert A, Zyzelewicz B, Mahmut MK, Oleszkiewicz A. Null cross-modal effects of olfactory training on visual, auditory or olfactory working memory in 6- to 9-year-old children. Neuropsychol Rehabil 2024:1-22. [PMID: 38762780 DOI: 10.1080/09602011.2024.2343484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 04/04/2024] [Indexed: 05/20/2024]
Abstract
Systematic exposure to odours (olfactory training, OT) is a method of smell loss treatment. Due to olfactory system projections to prefrontal brain areas, OT has been hypothesized to enhance cognitive functions, but its effects have been studied predominantly in adults. This study tested OT effects on working memory (WM), i.e., the ability to store and manipulate information for a short time, in healthy children aged 6-9 years. We expected OT to improve olfactory WM and establish cross-modal transfer to visual and auditory WM. Participants performed 12 weeks of bi-daily OT with either 4 odours (lemon, eucalyptus, rose, cloves; OT group) or odourless propylene glycol (placebo group). Pre- and post-training, participants' WM was measured utilizing odours (olfactory WM) or pictures (visual WM) and a word-span task (auditory WM). 84 children (40 girls) completed the study. The analyses revealed no changes in the WM performance following OT. The olfactory WM task was the most difficult for children, highlighting the need to include olfactory-related tasks in educational programmes to improve children's odour knowledge and memory, just as they learn about sounds and pictures. Further neuroimaging research is needed to fully understand the impact of OT on cognitive functions in children.
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Affiliation(s)
- Michal Pieniak
- Institute of Psychology, University of Wroclaw, Wroclaw, Poland
- Smell & Taste Clinic, Department of Otorhinolaryngology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Marta Rokosz
- Institute of Psychology, University of Wroclaw, Wroclaw, Poland
| | | | - Aleksandra Reichert
- Institute of Psychology, University of Wroclaw, Wroclaw, Poland
- Smell & Taste Clinic, Department of Otorhinolaryngology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | | | - Mehmet K Mahmut
- Food, Flavour and Fragrance Lab, School of Psychological Sciences, Macquarie University, Sydney, Australia
| | - Anna Oleszkiewicz
- Institute of Psychology, University of Wroclaw, Wroclaw, Poland
- Smell & Taste Clinic, Department of Otorhinolaryngology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
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5
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Poirier AC, Melin AD. Smell throughout the life course. Evol Anthropol 2024:e22030. [PMID: 38704704 DOI: 10.1002/evan.22030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 04/12/2024] [Accepted: 04/18/2024] [Indexed: 05/07/2024]
Abstract
The sense of smell is an important mediator of health and sociality at all stages of life, yet it has received limited attention in our lineage. Olfaction starts in utero and participates in the establishment of social bonds in children, and of romantic and sexual relationships after puberty. Smell further plays a key role in food assessment and danger avoidance; in modern societies, it also guides our consumer behavior. Sensory abilities typically decrease with age and can be impacted by diseases, with repercussions on health and well-being. Here, we critically review our current understanding of human olfactory communication to refute outdated notions that our sense of smell is of low importance. We provide a summary of the biology of olfaction, give a prospective overview of the importance of the sense of smell throughout the life course, and conclude with an outline of the limitations and future directions in this field.
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Affiliation(s)
- Alice C Poirier
- Department of Anthropology and Archaeology, University of Calgary, Calgary, Alberta, Canada
| | - Amanda D Melin
- Department of Anthropology and Archaeology, University of Calgary, Calgary, Alberta, Canada
- Department of Medical Genetics, University of Calgary, Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada
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6
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Merle-Nguyen L, Ando-Grard O, Bourgon C, St Albin A, Jacquelin J, Klonjkowski B, Le Poder S, Meunier N. Early corticosteroid treatment enhances recovery from SARS-CoV-2 induced loss of smell in hamster. Brain Behav Immun 2024; 118:78-89. [PMID: 38367845 DOI: 10.1016/j.bbi.2024.02.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 02/03/2024] [Accepted: 02/14/2024] [Indexed: 02/19/2024] Open
Abstract
Among the numerous long COVID symptoms, olfactory dysfunction persists in ∼10 % of patients suffering from SARS-CoV-2 induced anosmia. Among the few potential therapies, corticoid treatment has been used for its anti-inflammatory effect with mixed success in patients. In this study, we explored its impact using hamster as an animal model. SARS-CoV-2 infected hamsters lose their smell abilities and this loss is correlated with damage of the olfactory epithelium and persistent presence of innate immunity cells. We started a dexamethasone treatment 2 days post infection, when olfaction was already impacted, until 11 days post infection when it started to recover. We observed an improvement of olfactory capacities in the animals treated with corticoid compared to those treated with vehicle. This recovery was not related to differences in the remaining damage to the olfactory epithelium, which was similar in both groups. This improvement was however correlated with a reduced inflammation in the olfactory epithelium with a local increase of the mature olfactory neuron population. Surprisingly, at 11 days post infection, we observed an increased and disorganized presence of immature olfactory neurons, especially in persistent inflammatory zones of the epithelium. This unusual population of immature olfactory neurons coincided with a strong increase of olfactory epithelium proliferation in both groups. Our results indicate that persistent inflammation of the olfactory epithelium following SARS-CoV-2 infection may alter the extent and speed of regeneration of the olfactory neuron population, and that corticoid treatment is effective to limit inflammation and improve olfaction recovery following SARS-CoV-2 infection.
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Affiliation(s)
- Laetitia Merle-Nguyen
- Unité de Virologie et Immunologie Moléculaires (UR892), INRAE, Université Paris-Saclay, Jouy-en-Josas, France
| | - Ophélie Ando-Grard
- Unité de Virologie et Immunologie Moléculaires (UR892), INRAE, Université Paris-Saclay, Jouy-en-Josas, France
| | - Clara Bourgon
- Unité de Virologie et Immunologie Moléculaires (UR892), INRAE, Université Paris-Saclay, Jouy-en-Josas, France
| | - Audrey St Albin
- Unité de Virologie et Immunologie Moléculaires (UR892), INRAE, Université Paris-Saclay, Jouy-en-Josas, France
| | - Juliette Jacquelin
- Unité de Virologie et Immunologie Moléculaires (UR892), INRAE, Université Paris-Saclay, Jouy-en-Josas, France
| | - Bernard Klonjkowski
- UMR 1161 Virologie, INRAE-ENVA-ANSES, École Nationale Vétérinaire d'Alfort, Maisons-Alfort, 94704 Paris, France
| | - Sophie Le Poder
- UMR 1161 Virologie, INRAE-ENVA-ANSES, École Nationale Vétérinaire d'Alfort, Maisons-Alfort, 94704 Paris, France
| | - Nicolas Meunier
- Unité de Virologie et Immunologie Moléculaires (UR892), INRAE, Université Paris-Saclay, Jouy-en-Josas, France.
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Dekeyser A, Huart C, Hummel T, Hox V. Olfactory Loss in Rhinosinusitis: Mechanisms of Loss and Recovery. Int J Mol Sci 2024; 25:4460. [PMID: 38674045 PMCID: PMC11050448 DOI: 10.3390/ijms25084460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/12/2024] [Accepted: 04/16/2024] [Indexed: 04/28/2024] Open
Abstract
Chronic rhinosinusitis (CRS) is a highly prevalent disease and up to 83% of CRS patients suffer from olfactory dysfunction (OD). Because OD is specifically seen in those CRS patients that present with a type 2 eosinophilic inflammation, it is believed that type 2 inflammatory mediators at the level of the olfactory epithelium are involved in the development of this olfactory loss. However, due to the difficulties in obtaining tissue from the olfactory epithelium, little is known about the true mechanisms of inflammatory OD. Thanks to the COVID-19 pandemic, interest in olfaction has been growing rapidly and several studies have been focusing on disease mechanisms of OD in inflammatory conditions. In this paper, we summarize the most recent data exploring the pathophysiological mechanisms underlying OD in CRS. We also review what is known about the potential capacity of olfactory recovery of the currently available treatments in those patients.
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Affiliation(s)
- Agnès Dekeyser
- Laboratory of Pneumology, ENT (Airways) and Dermatology (Skin) (LUNS), Institute of Experimental and Clinical Research (IREC), UCLouvain, 1200 Brussels, Belgium; (A.D.); (C.H.)
| | - Caroline Huart
- Laboratory of Pneumology, ENT (Airways) and Dermatology (Skin) (LUNS), Institute of Experimental and Clinical Research (IREC), UCLouvain, 1200 Brussels, Belgium; (A.D.); (C.H.)
- Department of Otorhinolaryngology, Head and Neck Surgery, Cliniques Universitaires Saint-Luc, 1200 Brussels, Belgium
| | - Thomas Hummel
- Smell and Taste Clinic, Department of Otorhinolaryngology, University Hospital Carl Gustav Carus, TU Dresden, 01307 Dresden, Germany;
| | - Valérie Hox
- Laboratory of Pneumology, ENT (Airways) and Dermatology (Skin) (LUNS), Institute of Experimental and Clinical Research (IREC), UCLouvain, 1200 Brussels, Belgium; (A.D.); (C.H.)
- Department of Otorhinolaryngology, Head and Neck Surgery, Cliniques Universitaires Saint-Luc, 1200 Brussels, Belgium
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Maniaci A, Lavalle S, Masiello E, Lechien JR, Vaira L, Boscolo-Rizzo P, Musa M, Gagliano C, Zeppieri M. Platelet-Rich Plasma (PRP) in the Treatment of Long COVID Olfactory Disorders: A Comprehensive Review. Biomedicines 2024; 12:808. [PMID: 38672163 PMCID: PMC11048638 DOI: 10.3390/biomedicines12040808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 04/02/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024] Open
Abstract
Background: Long COVID has brought numerous challenges to healthcare, with olfactory dysfunction (OD) being a particularly distressing outcome for many patients. The persistent loss of smell significantly diminishes the affected individual's quality of life. Recent attention has been drawn to the potential of platelet-rich plasma (PRP) therapy as a treatment for OD. This comprehensive review aims to evaluate the effectiveness of PRP therapy in ameliorating OD, especially when associated with long-term COVID-19. Methods: We executed a comprehensive search of the literature, encompassing clinical trials and observational studies that utilized PRP in treating OD limited to COVID-19. We retrieved and comprehensively discussed data such as design, participant demographics, and reported outcomes, focusing on the efficacy and safety of PRP therapy for OD in COVID-19 patients. Results: Our comprehensive analysis interestingly found promising perspectives for PRP in OD following COVID-19 infection. The collective data indicate that PRP therapy contributed to a significant improvement in olfactory function after COVID-19 infection. Conclusions: The evidence amassed suggests that PRP is a promising and safe therapeutic option for OD, including cases attributable to Long COVID-19. The observed uniform enhancement of olfactory function in patients receiving PRP highlights the necessity for well-designed, controlled trials. Such studies would help to refine treatment protocols and more definitively ascertain the efficacy of PRP in a broader, more varied patient cohort.
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Affiliation(s)
- Antonino Maniaci
- Faculty of Medicine and Surgery, University of Enna “Kore”, Piazza dell’Università, 94100 Enna, EN, Italy; (A.M.)
- Research Committee of Young Otolaryngologists of International Federation of Otorhinolaryngological Societies (World Ear, Nose, and Throat Federation), 13005 Paris, France
| | - Salvatore Lavalle
- Faculty of Medicine and Surgery, University of Enna “Kore”, Piazza dell’Università, 94100 Enna, EN, Italy; (A.M.)
| | - Edoardo Masiello
- Clinical and Experimental Radiology Unit, Experimental Imaging Center, IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, MI, Italy
| | - Jerome R. Lechien
- Research Committee of Young Otolaryngologists of International Federation of Otorhinolaryngological Societies (World Ear, Nose, and Throat Federation), 13005 Paris, France
- Department of Human Anatomy and Experimental Oncology, Faculty of Medicine, UMONS Research Institute for Health Sciences and Technology, University of Mons (UMons), 7000 Mons, Belgium
| | - Luigi Vaira
- Research Committee of Young Otolaryngologists of International Federation of Otorhinolaryngological Societies (World Ear, Nose, and Throat Federation), 13005 Paris, France
- Maxillofacial Surgery Operative Unit, Department of Medicine, Surgery and Pharmacy, University of Sassari, 07100 Sassari, SS, Italy
- Biomedical Science Department, Biomedical Science Ph.D. School, University of Sassari, 07100 Sassari, SS, Italy
| | - Paolo Boscolo-Rizzo
- Department of Medical, Surgical, and Health Sciences, Section of Otolaryngology, University of Trieste, 34149 Trieste, TS, Italy
| | - Mutali Musa
- Department of Optometry, University of Benin, Benin City 300238, Nigeria
| | - Caterina Gagliano
- Faculty of Medicine and Surgery, University of Enna “Kore”, Piazza dell’Università, 94100 Enna, EN, Italy; (A.M.)
- Eye Clinic Catania, University San Marco Hospital, Viale Carlo Azeglio Ciampi, 95121 Catania, CT, Italy
| | - Marco Zeppieri
- Department of Ophthalmology, University Hospital of Udine, p.le S. Maria della Misericordia 15, 33100 Udine, UD, Italy
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9
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Genetzaki S, Nikolaidis V, Markou K, Konstantinidis I. Olfactory training with four and eight odors: comparison with clinical testing and olfactory bulb volumetrics. Eur Arch Otorhinolaryngol 2024; 281:497-502. [PMID: 37924364 PMCID: PMC10764551 DOI: 10.1007/s00405-023-08283-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 10/09/2023] [Indexed: 11/06/2023]
Abstract
PURPOSE Post-infectious olfactory dysfunction (PIOD) is one of the most common causes of olfactory impairment but has limited treatment options. Recently, olfactory training (OT) has been considered an effective treatment method; however, several questions have arisen regarding its optimal scheme. The aim of this study was to assess whether an OT scheme with 8 odors is more effective than the classic OT scheme with 4 odors by comparing psychophysical test results and olfactory bulb (OB) volumetrics. METHODS In this prospective cohort study, 72 patients with PIOD were included. The patients followed either the classic 4-odor OT scheme (COT; n = 34 patients) or an extended 8-odor scheme (EOT; n = 38 patients) for 16 weeks. All patients underwent olfactory testing with a Sniffin'Sticks battery test at 0, 8, and 16 weeks. Of the patients, 38 underwent brain magnetic resonance imaging for OB volumetric assessment before and after treatment. RESULTS The comparison of the olfactory test results did not show any significant difference between the two study groups, in agreement with the OB volumetrics. The convex OB showed better test results than the non-convex OB, with significantly better improvement after treatment regardless of OT type. The EOT group presented significantly better adherence than the COT group. CONCLUSION The number of odors did not appear to play a significant role in the effect of the OT. However, the training scheme with more than four odors showed better adherence among the patients in a long-term treatment plan. The shape of the OB may have prognostic value in clinical assessment and warrants further investigation.
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Affiliation(s)
- Sotiria Genetzaki
- 2nd ORL Academic Department, Aristotle University, Thessaloniki, Greece
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10
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Chen B, Boesen A, Olesch FT, Hummel T. A Life Without Smell: Olfactory Function in People Working in Odorless Rooms. Laryngoscope 2024; 134:382-387. [PMID: 37665094 DOI: 10.1002/lary.31015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/24/2023] [Accepted: 08/18/2023] [Indexed: 09/05/2023]
Abstract
OBJECTIVES Odorous stimulation helps to maintain or to improve olfactory function. In contrast, odor deprivation has been suggested to facilitate olfactory impairment. The aim of this study was to investigate the effects of odor deprivation in people working in an odorless environment. METHODS Fifty people working in an odorless environment for extended periods of time and 50 people not working in such environments were recruited. The participants were examined for olfactory function (using Sniffin' Sticks), nasal airflow (using peak nasal inspiratory flowmetry), self-rated olfactory function, self-rated nasal airflow, and well-being. Correlation analyses were used to explore the associations between the duration of working in odorless environment and olfaction, nasal airflow, and well-being. RESULTS The cleanroom workers exhibited slightly, but significantly reduced olfactory scores (sensitivity 7.0 ± 2.5, discrimination 11.4 ± 1.8) compared with controls (sensitivity 8.9 ± 2.5, F = 4.33, p = 0.03; discrimination 12.7 ± 1.6. F = 5.50, p = 0.001), even when controlling for age and rated nasal patency, with their self-rated olfactory function being not affected. The years of working in cleanrooms were negatively associated with olfactory function (r = 0.35, p = 0.013). No significant correlations were observed between scores of olfactory function, nasal patency, and well-being. CONCLUSION Compared with controls cleanroom workers exhibited slightly, but significantly lower olfactory scores, nasal peak flow, and well-being. Their decreased odor sensitivity was found to be associated with the number of years they had worked in the cleanroom. Overall, these results may suggest that odorous stimulation supports olfactory functioning. LEVEL OF EVIDENCE 4 Laryngoscope, 134:382-387, 2024.
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Affiliation(s)
- B Chen
- Smell & Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden, Germany
- Geriatric Neuroscience Center, The Affiliated Brain Hospital of Guangzhou Medical University, Guangzhou, China
| | - A Boesen
- Smell & Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden, Germany
| | - F T Olesch
- Smell & Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden, Germany
| | - T Hummel
- Smell & Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden, Germany
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Faria V, Joshi A, Mignot C, Thaploo D, Weise S, Hummel T. Neuroimaging the Development of Olfactory Function in a Woman With No Olfactory Bulbs. JAMA Otolaryngol Head Neck Surg 2024; 150:81-83. [PMID: 38032618 DOI: 10.1001/jamaoto.2023.3667] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
This case report describes a woman with lifelong anosmia in her 20s who presented with the acquisition of unpleasant olfactory phantoms.
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Affiliation(s)
- Vanda Faria
- Smell and Taste Clinic, Department of Otorhinolaryngology, Technical University Dresden, Dresden, Germany
- Department of Psychology, Uppsala University, Uppsala, Sweden
- Brain and Eye Pain Imaging Lab, Pain and Affective Neuroscience Center, Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Akshita Joshi
- Smell and Taste Clinic, Department of Otorhinolaryngology, Technical University Dresden, Dresden, Germany
| | - Coralie Mignot
- Smell and Taste Clinic, Department of Otorhinolaryngology, Technical University Dresden, Dresden, Germany
| | - Divesh Thaploo
- Smell and Taste Clinic, Department of Otorhinolaryngology, Technical University Dresden, Dresden, Germany
| | - Susanne Weise
- Smell and Taste Clinic, Department of Otorhinolaryngology, Technical University Dresden, Dresden, Germany
| | - Thomas Hummel
- Smell and Taste Clinic, Department of Otorhinolaryngology, Technical University Dresden, Dresden, Germany
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12
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Jeffs QL, Prather JF, Todd WD. Potential neural substrates underlying circadian and olfactory disruptions in preclinical Alzheimer's disease. Front Neurosci 2023; 17:1295998. [PMID: 38094003 PMCID: PMC10716239 DOI: 10.3389/fnins.2023.1295998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Accepted: 11/13/2023] [Indexed: 02/01/2024] Open
Abstract
Alzheimer's disease (AD) is the leading cause of dementia, with over 45 million patients worldwide, and poses significant economic and emotional burdens to both patients and caregivers, significantly raising the number of those affected. Unfortunately, much of the existing research on the disease only addresses a small subset of associated symptomologies and pathologies. In this review, we propose to target the earliest stages of the disease, when symptomology first arises. In these stages, before the onset of hallmark symptoms of AD such as cognitive impairments and memory loss, circadian and olfactory disruptions arise and are detectable. Functional similarities between circadian and olfactory systems provide a basis upon which to seek out common mechanisms in AD which may target them early on in the disease. Existing studies of interactions between these systems, while intriguing, leave open the question of the neural substrates underlying them. Potential substrates for such interactions are proposed in this review, such as indirect projections that may functionally connect the two systems and dopaminergic signaling. These substrates may have significant implications for mechanisms underlying disruptions to circadian and olfactory function in early stages of AD. In this review, we propose early detection of AD using a combination of circadian and olfactory deficits and subsequent early treatment of these deficits may provide profound benefits to both patients and caregivers. Additionally, we suggest that targeting research toward the intersection of these two systems in AD could uncover mechanisms underlying the broader set of symptoms and pathologies that currently elude researchers.
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Affiliation(s)
| | | | - William D. Todd
- Department of Zoology and Physiology, Program in Neuroscience, University of Wyoming, Laramie, WY, United States
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Dal Bò E, Natali L, Gentili C, Cecchetto C. Low odor awareness predicts reduced olfactory abilities in women with depressive symptoms, but not with anxiety symptoms. J Affect Disord 2023; 338:171-179. [PMID: 37290528 DOI: 10.1016/j.jad.2023.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 05/12/2023] [Accepted: 06/04/2023] [Indexed: 06/10/2023]
Abstract
BACKGROUND Olfactory disorders and affective symptoms are tightly related. However, the factors underlying this association are not yet understood. One candidate factor is "odor awareness": the degree of attention individuals pays to the odors. However, the association between odor awareness and olfactory abilities in individuals with affective symptoms has not been clarified yet. METHOD The present study examined whether odor awareness may moderate (a) the relation between olfactory dysfunctions and depressive and anxiety symptoms; (b) the relation between the perceptual ratings of the odors and depressive and anxiety symptoms in a sample of healthy women (n = 214). Self-report measures of depression and anxiety were collected, whereas the Sniffin' Stick test was employed to measure olfactory abilities. RESULTS Linear regression analysis revealed that individuals with higher depressive symptoms presented lower olfactory abilities and that odor awareness was a significant moderator of the association between depressive symptoms and olfactory abilities. Anxiety symptoms were not related to any of the olfactory abilities considered, and this relationship did not change according to odor awareness. The familiarity rating of the odor was significantly predicted by odor awareness. These results were confirmed by Bayesian statistics. LIMITATIONS The sample was composed only of women. CONCLUSIONS In a healthy population of women, only the presence of depressive symptoms is related to reduced olfactory performance. Odor awareness may be implicated in the development and maintenance of olfactory dysfunction; hence it could be used as a useful target for specific treatments in clinical settings.
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Affiliation(s)
- Elisa Dal Bò
- Padova Neuroscience Center (PNC), University of Padua, Via Orus 2/B, 35131 Padua, Italy; Department of General Psychology, University of Padua, Via Venezia 8, 35131 Padua, Italy.
| | - Ludovica Natali
- Department of General Psychology, University of Padua, Via Venezia 8, 35131 Padua, Italy; Centro di Ateneo Servizi Clinici Universitari Psicologici (SCUP), Via Belzoni, 84, 35121 Padua, Italy
| | - Claudio Gentili
- Padova Neuroscience Center (PNC), University of Padua, Via Orus 2/B, 35131 Padua, Italy; Department of General Psychology, University of Padua, Via Venezia 8, 35131 Padua, Italy; Centro di Ateneo Servizi Clinici Universitari Psicologici (SCUP), Via Belzoni, 84, 35121 Padua, Italy
| | - Cinzia Cecchetto
- Padova Neuroscience Center (PNC), University of Padua, Via Orus 2/B, 35131 Padua, Italy
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Pieniak M, Seidel K, Oleszkiewicz A, Gellrich J, Karpinski C, Fitze G, Schriever VA. Olfactory training effects in children after mild traumatic brain injury. Brain Inj 2023; 37:1272-1284. [PMID: 37486172 DOI: 10.1080/02699052.2023.2237889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 05/29/2023] [Accepted: 06/12/2023] [Indexed: 07/25/2023]
Abstract
OBJECTIVE Mild traumatic brain injury (mTBI) might impair the sense of smell and cognitive functioning. Repeated, systematic exposure to odors, i.e., olfactory training (OT) has been proposed for treatment of olfactory dysfunctions, including post-traumatic smell loss. Additionally, OT has been shown to mitigate cognitive deterioration in older population and enhance selected cognitive functions in adults. We aimed to investigate olfactory and cognitive effects of OT in the pediatric population after mTBI, likely to exhibit cognitive and olfactory deficits. METHODS Our study comprised 159 children after mTBI and healthy controls aged 6-16 years (M = 9.68 ± 2.78 years, 107 males), who performed 6-months-long OT with a set of 4 either high- or low-concentrated odors. Before and after OT we assessed olfactory functions, fluid intelligence, and executive functions. RESULTS OT with low-concentrated odors increased olfactory sensitivity in children after mTBI. Regardless of health status, children who underwent OT with low-concentrated odors had higher fluid intelligence scores at post-training measurement, whereas scores of children performing OT with high-concentrated odors did not change. CONCLUSION Our study suggests that OT with low-concentrated odors might accelerate rehabilitation of olfactory sensitivity in children after mTBI and support cognitive functions in the area of fluid intelligence regardless of head trauma.
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Affiliation(s)
- Michal Pieniak
- Smell & Taste Clinic, Department of Otorhinolaryngology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
- Faculty of Historical and Pedagogical Sciences, Institute of Psychology, University of Wrocław, Wroclaw, Poland
| | - Katharina Seidel
- Abteilung Neuropädiatrie, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Anna Oleszkiewicz
- Smell & Taste Clinic, Department of Otorhinolaryngology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
- Faculty of Historical and Pedagogical Sciences, Institute of Psychology, University of Wrocław, Wroclaw, Poland
| | - Janine Gellrich
- Abteilung Neuropädiatrie, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Christian Karpinski
- Klinik Und Poliklinik Für Kinderchirurgie, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Guido Fitze
- Klinik Und Poliklinik Für Kinderchirurgie, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Valentin A Schriever
- Abteilung Neuropädiatrie, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
- Center for Chronically Sick Children (Sozialpädiatrisches Zentrum, SPZ), Charité - Universitätsmedizin Berlin, Berlin, Germany
- Department of Pediatric Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany
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Athanassi A, Breton M, Chalençon L, Brunelin J, Didier A, Bath K, Mandairon N. Chronic unpredictable mild stress alters odor hedonics and adult olfactory neurogenesis in mice. Front Neurosci 2023; 17:1224941. [PMID: 37600017 PMCID: PMC10435088 DOI: 10.3389/fnins.2023.1224941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 07/17/2023] [Indexed: 08/22/2023] Open
Abstract
Experiencing chronic stress significantly increases the risk for depression. Depression is a complex disorder with varied symptoms across patients. However, feeling of sadness and decreased motivation, and diminished feeling of pleasure (anhedonia) appear to be core to most depressive pathology. Odorants are potent signals that serve a critical role in social interactions, avoiding danger, and consummatory behaviors. Diminished quality of olfactory function is associated with negative effects on quality of life leading to and aggravating the symptoms of depression. Odor hedonic value (I like or I dislike this smell) is a dominant feature of olfaction and guides approach or avoidance behavior of the odor source. The neural representation of the hedonic value of odorants is carried by the granule cells in the olfactory bulb, which functions to modulate the cortical relay of olfactory information. The granule cells of the olfactory bulb and those of the dentate gyrus are the two major populations of cells in the adult brain with continued neurogenesis into adulthood. In hippocampus, decreased neurogenesis has been linked to development or maintenance of depression symptoms. Here, we hypothesize that chronic mild stress can alter olfactory hedonics through effects on the olfactory bulb neurogenesis, contributing to the broader anhedonia phenotype in stress-associated depression. To test this, mice were subjected to chronic unpredictable mild stress and then tested on measures of depressive-like behaviors, odor hedonics, and measures of olfactory neurogenesis. Chronic unpredictable mild stress led to a selective effect on odor hedonics, diminishing attraction to pleasant but not unpleasant odorants, an effect that was accompanied by a specific decrease in adult neurogenesis and of the percentage of adult-born cells responding to pleasant odorants in the olfactory bulb.
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Affiliation(s)
- Anna Athanassi
- INSERM, U1028, CNRS UMR5292, Neuropop Team, Lyon Neuroscience Research Center, Université Claude Bernard Lyon 1, Université Jean Monnet, Bron, France
| | - Marine Breton
- INSERM, U1028, CNRS UMR5292, Neuropop Team, Lyon Neuroscience Research Center, Université Claude Bernard Lyon 1, Université Jean Monnet, Bron, France
| | - Laura Chalençon
- INSERM, U1028, CNRS UMR5292, Neuropop Team, Lyon Neuroscience Research Center, Université Claude Bernard Lyon 1, Université Jean Monnet, Bron, France
| | - Jérome Brunelin
- Centre Hospitalier Le Vinatier, Bron, France
- INSERM, U1028, CNRS UMR5292, PSYR2 Team, Lyon Neuroscience Research Center, Université Claude Bernard Lyon 1, Université Jean Monnet, Bron, France
| | - Anne Didier
- INSERM, U1028, CNRS UMR5292, Neuropop Team, Lyon Neuroscience Research Center, Université Claude Bernard Lyon 1, Université Jean Monnet, Bron, France
| | - Kevin Bath
- Division of Developmental Neuroscience, New York State Psychiatric Institute, Research Foundation for Mental Hygiene, New York, NY, United States
- Department of Psychiatry, Columbia University Medical College, New York, NY, United States
| | - Nathalie Mandairon
- INSERM, U1028, CNRS UMR5292, Neuropop Team, Lyon Neuroscience Research Center, Université Claude Bernard Lyon 1, Université Jean Monnet, Bron, France
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Woo CC, Miranda B, Sathishkumar M, Dehkordi-Vakil F, Yassa MA, Leon M. Overnight olfactory enrichment using an odorant diffuser improves memory and modifies the uncinate fasciculus in older adults. Front Neurosci 2023; 17:1200448. [PMID: 37554295 PMCID: PMC10405466 DOI: 10.3389/fnins.2023.1200448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 07/07/2023] [Indexed: 08/10/2023] Open
Abstract
OBJECTIVE Cognitive loss in older adults is a growing issue in our society, and there is a need to develop inexpensive, simple, effective in-home treatments. This study was conducted to explore the use of olfactory enrichment at night to improve cognitive ability in healthy older adults. METHODS Male and female older adults (N = 43), age 60-85, were enrolled in the study and randomly assigned to an Olfactory Enriched or Control group. Individuals in the enriched group were exposed to 7 different odorants a week, one per night, for 2 h, using an odorant diffuser. Individuals in the control group had the same experience with de minimis amounts of odorant. Neuropsychological assessments and fMRI scans were administered at the beginning of the study and after 6 months. RESULTS A statistically significant 226% improvement was observed in the enriched group compared to the control group on the Rey Auditory Verbal Learning Test and improved functioning was observed in the left uncinate fasciculus, as assessed by mean diffusivity. CONCLUSION Minimal olfactory enrichment administered at night produces improvements in both cognitive and neural functioning. Thus, olfactory enrichment may provide an effective and low-effort pathway to improved brain health.
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Affiliation(s)
- Cynthia C. Woo
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Blake Miranda
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
- Center for the Neurobiology of Learning and Memory, University of California, Irvine, Irvine, CA, United States
| | - Mithra Sathishkumar
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
- Center for the Neurobiology of Learning and Memory, University of California, Irvine, Irvine, CA, United States
| | | | - Michael A. Yassa
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
- Center for the Neurobiology of Learning and Memory, University of California, Irvine, Irvine, CA, United States
| | - Michael Leon
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
- Center for the Neurobiology of Learning and Memory, University of California, Irvine, Irvine, CA, United States
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA, United States
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Faria V, Dulheuer J, Joshi A, Wahl H, Klimova A, Haehner A, Gossrau G. Impact of a 12-week olfactory training programme in women with migraine with aura: protocol for a double-blind, randomised, placebo-controlled trial. BMJ Open 2023; 13:e071443. [PMID: 37419649 PMCID: PMC10335595 DOI: 10.1136/bmjopen-2022-071443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 06/04/2023] [Indexed: 07/09/2023] Open
Abstract
INTRODUCTION Migraine is a leading cause of disability and suffering worldwide. However, conventional pharmacological migraine preventive therapies are often challenging and accompanied by adverse effects. Recently, structured odour exposure has shown to successfully increase pain thresholds in patients with chronic back pain. Despite the importance of the olfactory system in migraine, there are no studies investigating the impact of structured odour exposure in patients with migraine. METHODS AND ANALYSIS This double-blind randomised placebo-controlled trial will be conducted at the Headache Clinic of the University Pain Center at TU Dresden, Germany and aims at investigating the impact of a 12-week structured exposure to odours in women with migraine. Fifty-four women between 18 and 55 years with migraine with aura will be recruited and randomised to training with odours and odourless training. The primary outcomes are mechanical and electrical pain thresholds. Secondary outcomes comprise olfactory threshold and the number of headache days. Other exploratory measurements are headache associated pain intensity, acute analgesic intake, symptoms of anxiety and depression, and quality of life. Additionally, this protocol assesses neuroanatomical and neurofunctional changes associated with the 12-week olfactory training. Data analysis will be executed on the basis of the general linear model considering repeated measurements. ETHICS AND DISSEMINATION Ethical approvals were obtained from the Ethics Board of the TU Dresden (Protocol No. BO-EK-353082020). Participation will only be possible after written informed consent is provided. Findings will be disseminated through peer-reviewed journals and scientific conferences. TRIAL REGISTRATION NUMBER DRKS00027399.
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Affiliation(s)
- Vanda Faria
- Department of Otorhinolaryngology, TU Dresden Faculty of Medicine Carl Gustav Carus, Dresden, Germany
- Department of Psychology, Uppsala University, Uppsala, Sweden
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Jana Dulheuer
- Department of Otorhinolaryngology, TU Dresden Faculty of Medicine Carl Gustav Carus, Dresden, Germany
| | - Akshita Joshi
- Department of Otorhinolaryngology, TU Dresden Faculty of Medicine Carl Gustav Carus, Dresden, Germany
| | - Hannes Wahl
- Intitute of Neuroradiology, TU Dresden Faculty of Medicine Carl Gustav Carus, Dresden, Germany
| | - Anna Klimova
- NCT Partner Site Dresden, Institute for Medical Informatics and Biometrics, TU Dresden Faculty of Medicine Carl Gustav Carus, Dresden, Germany
| | - Antje Haehner
- Department of Otorhinolaryngology, TU Dresden Faculty of Medicine Carl Gustav Carus, Dresden, Germany
| | - Gudrun Gossrau
- Interdisciplinary Pain Center, University Hospital, and Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany
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Hummel T, Power Guerra N, Gunder N, Hähner A, Menzel S. Olfactory Function and Olfactory Disorders. Laryngorhinootologie 2023; 102:S67-S92. [PMID: 37130532 PMCID: PMC10184680 DOI: 10.1055/a-1957-3267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The sense of smell is important. This became especially clear to patients with infection-related olfactory loss during the SARS-CoV-2 pandemic. We react, for example, to the body odors of other humans. The sense of smell warns us of danger, and it allows us to perceive flavors when eating and drinking. In essence, this means quality of life. Therefore, anosmia must be taken seriously. Although olfactory receptor neurons are characterized by regenerative capacity, anosmia is relatively common with about 5 % of anosmic people in the general population. Olfactory disorders are classified according to their causes (e. g., infections of the upper respiratory tract, traumatic brain injury, chronic rhinosinusitis, age) with the resulting different therapeutic options and prognoses. Thorough history taking is therefore important. A wide variety of tools are available for diagnosis, ranging from short screening tests and detailed multidimensional test procedures to electrophysiological and imaging methods. Thus, quantitative olfactory disorders are easily assessable and traceable. For qualitative olfactory disorders such as parosmia, however, no objectifying diagnostic procedures are currently available. Therapeutic options for olfactory disorders are limited. Nevertheless, there are effective options consisting of olfactory training as well as various additive drug therapies. The consultation and the competent discussion with the patients are of major importance.
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Affiliation(s)
- T Hummel
- Interdisziplinäres Zentrum Riechen und Schmecken, HNO Klinik, TU Dresden
| | - N Power Guerra
- Rudolf-Zenker-Institut für Experimentelle Chirurgie, Medizinische Universität Rostock, Rostock
| | - N Gunder
- Universitäts-HNO Klinik Dresden, Dresden
| | - A Hähner
- Interdisziplinäres Zentrum Riechen und Schmecken, HNO Klinik, TU Dresden
| | - S Menzel
- Interdisziplinäres Zentrum Riechen und Schmecken, HNO Klinik, TU Dresden
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Chen B, Stein A, Olesch FT, Hummel T. Odor deprivation influences human olfactory function. Physiol Behav 2023; 262:114090. [PMID: 36681230 DOI: 10.1016/j.physbeh.2023.114090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/06/2023] [Accepted: 01/13/2023] [Indexed: 01/20/2023]
Abstract
Odor deprivation leads to anatomical and neurochemical changes in the olfactory system, but its effect on human olfaction has not been systematically explored. The present randomized, controlled study aimed to investigate whether odor deprivation by different methods can affect olfactory function in humans. In the present study, sixty-one healthy participants were randomly assigned into three groups: a nasal device group (wearing an intranasal silicone air diversion system for 6-8 h daily), a mask group (wearing a filtering face piece for 6-8 h daily) and a control group (no special instructions in terms of wearing masks). Before and immediately after a 14-day study phase, all participants underwent assessments of olfactory function, nasal patency and well-being. Following the 2-week observation period, the nasal device group exhibited significantly reduced TDI scores (with especially pronounced reductions for odor threshold scores), and the mask group exhibited a minor increase in odor identification scores compared with the control group. The change in well-being scores was positively associated with changes in odor identification and TDI scores. Olfactory deprivation using an intranasal silicone air diversion device is associated with olfactory impairment (especially for odor thresholds). Highlighting the exposure-driven plasticity of the olfactory system, it may serve as a possible model of hyposmia in future studies. In addition, it may also prove useful in patients with parosmia, possibly reducing the burden of unpleasant odorous sensations.
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Affiliation(s)
- Ben Chen
- Smell & Taste Clinic, Department of Otorhinolaryngology, Dresden, TU Germany; Center for Geriatric Neuroscience, The Affiliated Brain Hospital of Guangzhou Medical University, Guangzhou, Guangdong Province, China.
| | - Anabel Stein
- Smell & Taste Clinic, Department of Otorhinolaryngology, Dresden, TU Germany
| | - Falk-Tony Olesch
- Smell & Taste Clinic, Department of Otorhinolaryngology, Dresden, TU Germany
| | - Thomas Hummel
- Smell & Taste Clinic, Department of Otorhinolaryngology, Dresden, TU Germany
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Hummel T, T. Liu D, A. Müller C, A. Stuck B, Welge-Lüssen A, Hähner A. Olfactory Dysfunction: Etiology, Diagnosis, and Treatment. DEUTSCHES ARZTEBLATT INTERNATIONAL 2023; 120:146-154. [PMID: 36647581 PMCID: PMC10198165 DOI: 10.3238/arztebl.m2022.0411] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 06/03/2022] [Accepted: 12/21/2022] [Indexed: 01/18/2023]
Abstract
BACKGROUND Disorders of the sense of smell have received greater attention because of the frequency with which they occur as a symptom of SARS-CoV-2 infection. Olfactory dysfunction can lead to profound reduction in quality of life and may arise from many different causes. METHODS A selective literature review was conducted with consideration of the current version of the guideline issued by the Association of the Scientific Medical Societies in Germany. RESULTS The cornerstones of diagnosis are the relevant medical history and psychophysical testing of olfactory function using standardized validated tests. Modern treatment strategies are oriented on the cause of the dysfunction. While treatment of the underlying inflammation takes precedence in patients with sinunasal dysosmia, olfactory training is the primary treatment option for other forms of the disorder. The prognosis is determined not only by the cause of the olfactory dysfunction and the patient's age, but also by the olfactory performance as measured at the time of diagnosis. CONCLUSION Options for the treatment of olfactory dysfunction are available but limited, depending on the cause. It is therefore important to carry out a detailed diagnostic work-up and keep the patient informed of the expected course and prognosis.
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Affiliation(s)
- Thomas Hummel
- Interdisciplinary Center for Smell and Taste, Department of Otorhinolaryngology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden
| | - David T. Liu
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Vienna General Hospital, Austria
| | - Christian A. Müller
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Vienna General Hospital, Austria
| | - Boris A. Stuck
- Department of Otorhinolaryngology, Head and Neck Surgery, Giessen and Marburg University Hospital Ltd., Marburg
| | - Antje Welge-Lüssen
- Interdisciplinary Center for Smell and Taste, Department of Otorhinolaryngology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden
| | - Antje Hähner
- Department of Otorhinolaryngology, Basel University Hospital, Switzerland
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Malekmakan L, Doostkam A, Iravani K, Roozbeh J, Sookhaklari MA, Maryam pakfetrat. Comparison between olfactory training and curcumin therapy in improving olfactory dysfunction in patients with chronic kidney disease. Heliyon 2023; 9:e14478. [PMID: 36967933 PMCID: PMC10031463 DOI: 10.1016/j.heliyon.2023.e14478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 03/01/2023] [Accepted: 03/08/2023] [Indexed: 03/14/2023] Open
Abstract
Objective Olfactory dysfunction can be seen in chronic kidney disease (CKD) patients. We aimed to investigate the effects of olfactory training and curcumin on olfactory dysfunction in CKD patients and compare their impact with a placebo. Methods We conducted a double-blind, randomized, placebo-controlled trial in CKD patients, 2021-2022. We enrolled 60 participants in our study into three groups (curcumin, training, and control). Participants were randomized into trials and control groups and assessed using the Iran-smell identification test (Iran-SIT), a questionnaire of olfactory disorders (QOD), and a self-assessment tool. P-value < 0.05 was considered statistically significant. Results We gathered 58 participants (mean age of 56.1 ± 2.5, 56.9% men). All the tests showed that curcumin improved olfactory function after the trial, though it was significant in QOD (17.5 ± 11.8 vs. 13.1 ± 9.7, p = 0.045) and self-assessment results (8.5 ± 3.1 vs. 9.5 ± 4.0, p = 0.047). Moreover, compared to baseline, training patients experienced an increase in their olfactory function in Iran-SIT (15.3 ± 4.9 vs. 18.8 ± 2.7, p = 0.001), QOD (19.0 ± 10.4 vs. 12.2 ± 9.9, p = 0.003), and self-assessment tools (6.8 ± 1.8 vs. 8.2 ± 3.1, p = 0.027). In contrast, the olfactory function was unchanged in control in all the tests (p > 0.05). Also, the improved change of Iran-SIT and QOD scores during the trial was more significant in training compared to the curcumin group (p < 0.002). Conclusion The findings of this study indicate that olfactory training, even more than curcumin, can improve olfactory function in CKD patients. This information may help manage olfactory dysfunction in the CKD population.
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22
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Watanabe K, Kokubun K, Yamakawa Y. Altered Grey Matter-Brain Healthcare Quotient: Interventions of Olfactory Training and Learning of Neuroplasticity. Life (Basel) 2023; 13:life13030667. [PMID: 36983823 PMCID: PMC10052964 DOI: 10.3390/life13030667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 02/09/2023] [Accepted: 02/24/2023] [Indexed: 03/05/2023] Open
Abstract
Recent studies revealed that grey matter (GM) changes due to various training and learning experiences, using magnetic resonance imaging. In this study, we investigate the effect of psychological characteristics and attitudes toward training and learning on GM changes. Ninety participants were recruited and distributed into three groups: an olfactory training group that underwent 40 olfactory training sessions designed for odour classification tasks, a group classified for learning of neuroplasticity and brain healthcare using a TED Talk video and 28 daily brain healthcare messages, and a control group. Further, we assessed psychological characteristics, such as curiosity and personal growth initiatives. In the olfactory training group, we conducted a questionnaire survey on olfactory training regarding their interests and sense of accomplishment. In the olfactory training group, the GM change was significantly correlated with the sense of achievement and interest in training. The learning of neuroplasticity and brain healthcare group showed a significantly smaller 2-month GM decline than did the control group. The Curiosity and Exploration Inventory-II scores were significantly correlated with GM changes in both intervention groups only. In conclusion, our result suggested that training or learning with a sense of accomplishment, interest, and curiosity would lead to greater GM changes.
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Affiliation(s)
- Keita Watanabe
- Institution of Open Innovation, Kyoto University, Kyoto 606-8501, Japan
- Correspondence:
| | - Keisuke Kokubun
- Smart-Aging Research Center, Tohoku University, Sendai 980-8575, Japan
| | - Yoshinori Yamakawa
- Institution of Open Innovation, Kyoto University, Kyoto 606-8501, Japan
- Institute of Innovative Research, Tokyo Institute of Technology, Tokyo 152-8550, Japan
- Academic and Industrial Innovation, Kobe University, Kobe 657-8501, Japan
- ImPACT Program of Council for Science, Technology, and Innovation (Cabinet Office, Government of Japan), Tokyo 100-8914, Japan
- BRAIN IMPACT General Incorporated Association, Kyoto 606-8501, Japan
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23
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von Bartheld CS, Wang L. Prevalence of Olfactory Dysfunction with the Omicron Variant of SARS-CoV-2: A Systematic Review and Meta-Analysis. Cells 2023; 12:430. [PMID: 36766771 PMCID: PMC9913864 DOI: 10.3390/cells12030430] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/19/2023] [Accepted: 01/25/2023] [Indexed: 01/31/2023] Open
Abstract
The omicron variant is thought to cause less olfactory dysfunction than previous variants of SARS-CoV-2, but the reported prevalence differs greatly between populations and studies. Our systematic review and meta-analysis provide information regarding regional differences in prevalence as well as an estimate of the global prevalence of olfactory dysfunction based on 62 studies reporting information on 626,035 patients infected with the omicron variant. Our estimate of the omicron-induced prevalence of olfactory dysfunction in populations of European ancestry is 11.7%, while it is significantly lower in all other populations, ranging between 1.9% and 4.9%. When ethnic differences and population sizes are considered, the global prevalence of omicron-induced olfactory dysfunction in adults is estimated to be 3.7%. Omicron's effect on olfaction is twofold to tenfold lower than that of the alpha or delta variants according to previous meta-analyses and our analysis of studies that directly compared the prevalence of olfactory dysfunction between omicron and previous variants. The profile of the prevalence differences between ethnicities mirrors the results of a recent genome-wide association study that connected a gene locus encoding an odorant-metabolizing enzyme, UDP glycosyltransferase, to the extent of COVID-19-related loss of smell. Our analysis is consistent with the hypothesis that this enzyme contributes to the observed population differences.
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Affiliation(s)
- Christopher S. von Bartheld
- Department of Physiology and Cell Biology, Reno School of Medicine, University of Nevada, Reno, NV 89557-0352, USA
| | - Lingchen Wang
- School of Public Health, University of Nevada, Reno, NV 89557-0275, USA
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24
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von Bartheld CS, Wang L. Prevalence of Olfactory Dysfunction with the Omicron Variant of SARS-CoV-2: A Systematic Review and Meta-analysis. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2022.12.16.22283582. [PMID: 36561176 PMCID: PMC9774228 DOI: 10.1101/2022.12.16.22283582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The omicron variant is thought to cause less olfactory dysfunction than previous variants of SARS-CoV-2, but the reported prevalence differs greatly between populations and studies. Our systematic review and meta-analysis provide information about regional differences in prevalence as well as an estimate of the global prevalence of olfactory dysfunction based on 62 studies reporting on 626,035 patients infected with the omicron variant. Our estimate of the omicron-induced prevalence of olfactory dysfunction in populations of European ancestry is 11.7%, while it is significantly lower in all other populations, ranging between 1.9% and 4.9%. When ethnic differences and population sizes are taken into account, the global prevalence of omicron-induced olfactory dysfunction in adults is estimated at 3.7%. Omicron’s effect on olfaction is twofold to tenfold lower than that of the alpha or delta variant, according to previous meta-analyses and our analysis of studies that directly compared prevalence of olfactory dysfunction between omicron and previous variants. The profile of prevalence differences between ethnicities mirrors the results of a recent genome-wide association study that implicated a gene locus encoding an odorant-metabolizing enzyme, UDP glycosyltransferase, to be linked to the extent of COVID-related loss of smell. Our analysis is consistent with the hypothesis that this enzyme contributes to the observed population differences.
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Affiliation(s)
- Christopher S. von Bartheld
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV, 89557-0352, United States
| | - Lingchen Wang
- School of Public Health, University of Nevada, Reno, Reno, NV, 89557-0275, United States
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25
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Li Z, Anne A, Hummel T. Olfactory training: effects of multisensory integration, attention towards odors and physical activity. Chem Senses 2023; 48:bjad037. [PMID: 37715960 DOI: 10.1093/chemse/bjad037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Indexed: 09/18/2023] Open
Abstract
Olfactory training (OT) has been shown to be of value in the treatment of olfactory dysfunction. The present study aimed to investigate whether the efficacy of OT could be modulated with multisensory integration, attention towards odors, odor complexity, or physical activity assessed with a questionnaire. One hundred healthy participants were recruited and divided into 4 groups. Except for controls (n = 26, mean age ± SD = 36 ± 15 years) all participants performed OT 4 times a day. In the "video" group (n = 26, age 39 ± 19 years) OT was performed while watching specific and congruent video sequences. In the "counter" group (n = 24, 38 ± 17 years) participants additionally counted the number of odors 1 day per week, and in the "training only" group no additional measures were taken in addition to OT (n = 24, 38 ± 20 years). "Single-molecule" odorants or "complex mixtures" were distributed randomly for training stimulation. Sniffin' sticks tests (odor identification, odor discrimination, and odor threshold), cognitive tests, and a series of scales were measured at both baseline and after 3 months of OT. The degree of physical activity was recorded with a questionnaire. Olfactory function improved in the video and counter groups after OT, especially for odor threshold and discrimination. Yet, odor complexity and the degree of physical activity had limited effects on olfactory improvement after OT. Both multisensory interaction and attention towards odors plus OT appeared to facilitate improvement of olfactory function in healthy individuals compared with OT alone and controls, which could provide new promising treatments for clinical applications.
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Affiliation(s)
- Zetian Li
- Smell and Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Fetscherstarsse 74, 01307 Dresden, Germany
| | - Abriat Anne
- The Smell and Taste Lab, Rue Cramer 6, 1202 Genève, Switzerland
| | - Thomas Hummel
- Smell and Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Fetscherstarsse 74, 01307 Dresden, Germany
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