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McLaren AMR, Kawaja MD. Olfactory Dysfunction and Alzheimer's Disease: A Review. J Alzheimers Dis 2024; 99:811-827. [PMID: 38728185 DOI: 10.3233/jad-231377] [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] [Indexed: 05/12/2024]
Abstract
Alzheimer's disease is the most common cause of dementia, and it is one of the leading causes of death globally. Identification and validation of biomarkers that herald the onset and progression of Alzheimer's disease is of paramount importance for early reliable diagnosis and effective pharmacological therapy commencement. A substantial body of evidence has emerged demonstrating that olfactory dysfunction is a preclinical symptom of neurodegenerative diseases including Alzheimer's disease. While a correlation between olfactory dysfunction and Alzheimer's disease onset and progression in humans exists, the mechanism underlying this relationship remains unknown. The aim of this article is to review the current state of knowledge regarding the range of potential factors that may contribute to the development of Alzheimer's disease-related olfactory dysfunction. This review predominantly focuses on genetic mutations associated with Alzheimer's disease including amyloid-β protein precursor, presenilin 1 and 2, and apolipoprotein E mutations, that may (in varying ways) drive the cellular events that lead to and sustain olfactory dysfunction.
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Affiliation(s)
| | - Michael D Kawaja
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, ON, Canada
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, ON, Canada
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Mi Y, Ma X, Du S, Du C, Li X, Tan H, Zhang J, Zhang Q, Shi W, Zhang G, Tian Y. Olfactory function changes and the predictive performance of the Chinese Smell Identification Test in patients with mild cognitive impairment and Alzheimer's disease. Front Aging Neurosci 2023; 15:1068708. [PMID: 36861124 PMCID: PMC9969891 DOI: 10.3389/fnagi.2023.1068708] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 01/16/2023] [Indexed: 02/16/2023] Open
Abstract
Objectives Olfactory disorder is one of the sensory features that reflects a decline in cognitive function. However, olfactory changes and the discernibility of smell testing in the aging population have yet to be fully elucidated. Therefore, this study aimed to examine the effectiveness of the Chinese Smell Identification Test (CSIT) in distinguishing individuals with cognitive decline from those with normal aging and to determine whether the patients with MCI and AD show changes in their olfactory identification abilities. Methods This cross-sectional study included eligible participants aged over 50 years between October 2019 and December 2021. The participants were divided into three groups: individuals with mild cognitive impairment (MCI), individuals with Alzheimer's disease (AD), and cognitively normal controls (NCs). All participants were assessed using neuropsychiatric scales, the Activity of Daily Living scale, and the 16-odor cognitive state test (CSIT) test. The test scores and the severity of olfactory impairment were also recorded for each participant. Results In total, 366 eligible participants were recruited, including 188 participants with MCI, 42 patients with AD, and 136 NCs. Patients with MCI achieved a mean CSIT score of 13.06 ± 2.05, while patients with AD achieved a mean score of 11.38 ± 3.25. These scores were significantly lower than those of the NC group (14.6 ± 1.57; P < 0.001). An analysis showed that 19.9% of NCs exhibited mild olfactory impairment, while 52.7% of patients with MCI and 69% of patients with AD exhibited mild to severe olfactory impairment. The CSIT score was positively correlated with the MoCA and MMSE scores. The CIST score and the severity of olfactory impairment were identified as robust indicators for MCI and AD, even after adjusting for age, gender, and level of education. Age and educational level were identified as two important confounding factors that influence cognitive function. However, no significant interactive effects were observed between these confounders and CIST scores in determining the risk of MCI. The area under the ROC curve (AUC) generated from the ROC analysis was 0.738 and 0.813 in distinguishing patients with MCI and patients with AD from NCs based on the CIST scores, respectively. The optimal cutoff for distinguishing MCI from NCs was 13, and for distinguishing AD from NCs was 11. The AUC for distinguishing AD from MCI was 0.62. Conclusions The olfactory identification function is frequently affected in patients with MCI and patients with AD. CSIT is a beneficial tool for the early screening of cognitive impairment among elderly patients with cognitive or memory issues.
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Affiliation(s)
- Yan Mi
- Department of Neurology, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China
| | - Xiaojuan Ma
- Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Clinical Medical Research Center, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China
| | - Shan Du
- Department of Neurology, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China
| | - Chengxue Du
- Department of Neurology, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China
| | - Xiaobo Li
- Department of Neurology, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China
| | - Huihui Tan
- Department of Neurology, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China
| | - Jie Zhang
- Department of Neurology, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China
| | - Qi Zhang
- Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Clinical Medical Research Center, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China
| | - Wenzhen Shi
- Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Clinical Medical Research Center, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Wenzhen Shi ✉
| | - Gejuan Zhang
- Department of Neurology, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Gejuan Zhang ✉
| | - Ye Tian
- Department of Neurology, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases, The Affiliated Hospital of Northwest University, Xi'an No.3 Hospital, Xi'an, Shaanxi, China,*Correspondence: Ye Tian ✉
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Klarendic M, Zupanic E, Zalaznik M, Georgiev D, Tomazic J, Kojovic M. Olfactory evaluation in hospitalised and self-isolated patients with COVID-19: a single-centre experience on 55 cases. Postgrad Med J 2022; 98:902-905. [PMID: 34772796 PMCID: PMC8594974 DOI: 10.1136/postgradmedj-2021-140315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 10/08/2021] [Indexed: 11/04/2022]
Abstract
BACKGROUND Smell loss is a common symptom of COVID-19 infection. Majority of the studies that evaluated olfactory impairment in COVID-19 used questionnaires (subjective smell evaluations) and did not compare the results with objective or semiobjective measures of smell. We performed smell testing in hospitalised and self-isolated patients with COVID-19 and control participants. METHODS Fifty-five COVID-19 and 44 control participants underwent smell testing, using Burghart Sniffin' Sticks 'Screening 12 Test'. Participants also rated their smelling capability on the numerical scale. Differences between groups and correlation between smell loss and time from acute onset of symptoms were tested, as well as correlation between results of smell test and subjective assessment of smell. RESULTS Hospitalised patients with COVID-19 correctly determined 6.5/12 odorants compared with 10/12 in the self-isolated and 11/12 in the control group (p<0.001). Hyposmia or anosmia were present in 87.5% of hospitalised and 29.0% of self-isolated patients (p<0.001). The correlation between subjective self-assessment and results of smell testing was non-significant in both groups of patients with COVID-19, while there was a moderate positive correlation (p=0.001, Spearman's correlation coefficient=0.499) in control participants. CONCLUSION Contrary to some previous reports suggesting that the presence of olfactory loss may predict milder course of disease, our study found that a vast majority of hospitalised patients with COVID-19 had prominent olfactory impairment. The absence of correlation between self-rated and objective smell evaluation in patients with COVID-19 indicates that subjective smell assessment is unreliable.
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Affiliation(s)
- Maja Klarendic
- Department of Neurology, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Medical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Eva Zupanic
- Department of Neurology, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Medical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Mateja Zalaznik
- Medical Faculty, University of Ljubljana, Ljubljana, Slovenia
- Department for Infectious Diseases, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Dejan Georgiev
- Department of Neurology, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Janez Tomazic
- Medical Faculty, University of Ljubljana, Ljubljana, Slovenia
- Department for Infectious Diseases, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Maja Kojovic
- Department of Neurology, University Medical Centre Ljubljana, Ljubljana, Slovenia
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4
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Yap AC, Mahendran R, Kua EH, Zhou W, Wang DY. Olfactory dysfunction is associated with mild cognitive impairment in community-dwelling older adults. Front Aging Neurosci 2022; 14:930686. [PMID: 36004001 PMCID: PMC9393534 DOI: 10.3389/fnagi.2022.930686] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 07/18/2022] [Indexed: 12/02/2022] Open
Abstract
Background Olfactory impairment is aging related and is associated with cognitive decline in older adults. However, it remains unclear if an olfactory impairment is associated with mild cognitive impairment (MCI) and the degree of impairment in the MCI subtypes. Materials and methods In a cohort of community-living older adults aged 60 years and above, 670 participants were recruited from the Community Health and Intergenerational (CHI) Study. Olfactory function was assessed using a locally developed nine-item smell test in association with neurocognitive assessments. Analysis of covariance (ANCOVA) was used to examine the association of smell identification score and clinical cognitive status while considering demographic, clinical, and neuropsychological factors with Bonferroni correction for group comparisons. Results Age-related smell detection between normal aging (NA) and MCI participants had no significant difference. The overall mean smell identification score in older adults was negatively correlated with age. The mean smell identification score of MCI participants was also not significantly different as compared with NA, but an amnestic MCI multiple domain (aMCI_MD) subgroup had significantly lower (impaired) mean smell identification scores compared with the NA and MCI single domain (amnestic and non-amnestic) group. Conclusion This study demonstrated that olfactory identification impairment is a comorbidity in older adults with amnestic MCI (aMCI) and is a potential marker associated with an early stage of a neurocognitive disorder. The smell test could act as a screening tool to help in the early detection of smell impairment for heterogeneous syndromes of MCI among community-dwelling older adults. Clinicians and researchers could benefit from utilizing the locally developed smell test to screen their patients or research participants before the initiation of an appropriate health intervention or in a clinical trial.
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Affiliation(s)
- Ai Che Yap
- Department of Food Science and Technology, National University of Singapore, Singapore, Singapore
| | - Rathi Mahendran
- Department of Psychological Medicine, Mind Science Centre, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Ee Heok Kua
- Department of Psychological Medicine, Mind Science Centre, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Psychological Medicine, National University Hospital, Singapore, Singapore
- *Correspondence: Ee Heok Kua,
| | - Weibiao Zhou
- Department of Food Science and Technology, National University of Singapore, Singapore, Singapore
- Weibiao Zhou,
| | - De Yun Wang
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- De Yun Wang,
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5
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Challakere Ramaswamy VM, Schofield PW. Olfaction and Executive Cognitive Performance: A Systematic Review. Front Psychol 2022; 13:871391. [PMID: 35615205 PMCID: PMC9125097 DOI: 10.3389/fpsyg.2022.871391] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 04/14/2022] [Indexed: 11/30/2022] Open
Abstract
Objective tests of olfaction are widely available to aid in the assessment of olfaction. Their clearest role is in the characterization of olfactory changes, either reported by or suspected in a patient. There is a rapidly growing literature concerned with the association of olfactory changes with certain neuropsychiatric conditions and the use of olfactory testing to supplement conventional assessments in clinical and research practice is evolving. Neural pathways important for olfactory processing overlap extensively with pathways important for cognitive functioning, and especially those important for executive functioning, many of which are concentrated in the frontal lobes. Previous work has identified associations between performance on certain olfactory tests (most frequently olfactory identification) and executive functioning and behavioral measures (e.g. of impulsivity). More recently, similar associations have also been identified in non-clinical samples, raising new questions as to the utility of olfactory test scores as proxy measures for non-olfactory phenomena. In this systemic review, we sought to identify studies, both clinical and non-clinical, that investigated the associations of olfaction with performance on tasks sensitive to frontal lobe functioning. Our search criteria led to the identification of 70 studies published in English. We examined in detail and tabulated the data from these studies, highlighted each study's key findings, and critically evaluated these studies. We use the results of this review to reflect on some of the current and future challenges concerning the use of olfactory testing in clinical neuropsychiatric practice and research and speculate on the potential benefits of administering phonemic fluency in combination with olfactory testing to enhance its predictive value.
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Affiliation(s)
- Vasudeva Murthy Challakere Ramaswamy
- School of Medicine and Public Health, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW, Australia
- *Correspondence: Vasudeva Murthy Challakere Ramaswamy
| | - Peter William Schofield
- School of Medicine and Public Health, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW, Australia
- Neuropsychiatry Service, Hunter New England Mental Health, New Lambton, NSW, Australia
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6
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Patel ZM, Holbrook EH, Turner JH, Adappa ND, Albers MW, Altundag A, Appenzeller S, Costanzo RM, Croy I, Davis GE, Dehgani-Mobaraki P, Doty RL, Duffy VB, Goldstein BJ, Gudis DA, Haehner A, Higgins TS, Hopkins C, Huart C, Hummel T, Jitaroon K, Kern RC, Khanwalkar AR, Kobayashi M, Kondo K, Lane AP, Lechner M, Leopold DA, Levy JM, Marmura MJ, Mclelland L, Miwa T, Moberg PJ, Mueller CA, Nigwekar SU, O'Brien EK, Paunescu TG, Pellegrino R, Philpott C, Pinto JM, Reiter ER, Roalf DR, Rowan NR, Schlosser RJ, Schwob J, Seiden AM, Smith TL, Soler ZM, Sowerby L, Tan BK, Thamboo A, Wrobel B, Yan CH. International consensus statement on allergy and rhinology: Olfaction. Int Forum Allergy Rhinol 2022; 12:327-680. [PMID: 35373533 DOI: 10.1002/alr.22929] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 01/01/2021] [Accepted: 11/19/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND The literature regarding clinical olfaction, olfactory loss, and olfactory dysfunction has expanded rapidly over the past two decades, with an exponential rise in the past year. There is substantial variability in the quality of this literature and a need to consolidate and critically review the evidence. It is with that aim that we have gathered experts from around the world to produce this International Consensus on Allergy and Rhinology: Olfaction (ICAR:O). METHODS Using previously described methodology, specific topics were developed relating to olfaction. Each topic was assigned a literature review, evidence-based review, or evidence-based review with recommendations format as dictated by available evidence and scope within the ICAR:O document. Following iterative reviews of each topic, the ICAR:O document was integrated and reviewed by all authors for final consensus. RESULTS The ICAR:O document reviews nearly 100 separate topics within the realm of olfaction, including diagnosis, epidemiology, disease burden, diagnosis, testing, etiology, treatment, and associated pathologies. CONCLUSION This critical review of the existing clinical olfaction literature provides much needed insight and clarity into the evaluation, diagnosis, and treatment of patients with olfactory dysfunction, while also clearly delineating gaps in our knowledge and evidence base that we should investigate further.
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Affiliation(s)
- Zara M Patel
- Otolaryngology, Stanford University School of Medicine, Stanford, California, USA
| | - Eric H Holbrook
- Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
| | - Justin H Turner
- Otolaryngology, Vanderbilt School of Medicine, Nashville, Tennessee, USA
| | - Nithin D Adappa
- Otolaryngology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Mark W Albers
- Neurology, Harvard Medical School, Boston, Massachusetts, USA
| | - Aytug Altundag
- Otolaryngology, Biruni University School of Medicine, İstanbul, Turkey
| | - Simone Appenzeller
- Rheumatology, School of Medical Sciences, University of Campinas, São Paulo, Brazil
| | - Richard M Costanzo
- Physiology and Biophysics and Otolaryngology, Virginia Commonwealth University School of Medicine, Richmond, Virginia, USA
| | - Ilona Croy
- Psychology and Psychosomatic Medicine, TU Dresden, Dresden, Germany
| | - Greg E Davis
- Otolaryngology, Proliance Surgeons, Seattle and Puyallup, Washington, USA
| | - Puya Dehgani-Mobaraki
- Associazione Naso Sano, Umbria Regional Registry of Volunteer Activities, Corciano, Italy
| | - Richard L Doty
- Smell and Taste Center, Otolaryngology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Valerie B Duffy
- Allied Health Sciences, University of Connecticut, Storrs, Connecticut, USA
| | | | - David A Gudis
- Otolaryngology, Columbia University Irving Medical Center, New York, USA
| | - Antje Haehner
- Smell and Taste, Otolaryngology, TU Dresden, Dresden, Germany
| | - Thomas S Higgins
- Otolaryngology, University of Louisville School of Medicine, Louisville, Kentucky, USA
| | - Claire Hopkins
- Otolaryngology, Guy's and St. Thomas' Hospitals, London Bridge Hospital, London, UK
| | - Caroline Huart
- Otorhinolaryngology, Cliniques universitaires Saint-Luc, Institute of Neuroscience, Université catholgique de Louvain, Brussels, Belgium
| | - Thomas Hummel
- Smell and Taste, Otolaryngology, TU Dresden, Dresden, Germany
| | | | - Robert C Kern
- Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Ashoke R Khanwalkar
- Otolaryngology, Stanford University School of Medicine, Stanford, California, USA
| | - Masayoshi Kobayashi
- Otorhinolaryngology-Head and Neck Surgery, Mie University Graduate School of Medicine, Mie, Japan
| | - Kenji Kondo
- Otolaryngology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - Andrew P Lane
- Otolaryngology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Matt Lechner
- Otolaryngology, Barts Health and University College London, London, UK
| | - Donald A Leopold
- Otolaryngology, University of Vermont Medical Center, Burlington, Vermont, USA
| | - Joshua M Levy
- Otolaryngology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Michael J Marmura
- Neurology Thomas Jefferson University School of Medicine, Philadelphia, Pennsylvania, USA
| | - Lisha Mclelland
- Otolaryngology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Takaki Miwa
- Otolaryngology, Kanazawa Medical University, Ishikawa, Japan
| | - Paul J Moberg
- Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | | | - Sagar U Nigwekar
- Division of Nephrology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Erin K O'Brien
- Otolaryngology, Mayo Clinic Rochester, Rochester, Minnesota, USA
| | - Teodor G Paunescu
- Division of Nephrology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | | | - Carl Philpott
- Otolaryngology, University of East Anglia, Norwich, UK
| | - Jayant M Pinto
- Otolaryngology, University of Chicago, Chicago, Illinois, USA
| | - Evan R Reiter
- Otolaryngology, Virginia Commonwealth University School of Medicine, Richmond, Virginia, USA
| | - David R Roalf
- Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Nicholas R Rowan
- Otolaryngology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Rodney J Schlosser
- Otolaryngology, Medical University of South Carolina, Mt Pleasant, South Carolina, USA
| | - James Schwob
- Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Allen M Seiden
- Otolaryngology, University of Cincinnati School of Medicine, Cincinnati, Ohio, USA
| | - Timothy L Smith
- Otolaryngology, Oregon Health and Sciences University, Portland, Oregon, USA
| | - Zachary M Soler
- Otolaryngology, Medical University of South Carolina, Mt Pleasant, South Carolina, USA
| | - Leigh Sowerby
- Otolaryngology, University of Western Ontario, London, Ontario, Canada
| | - Bruce K Tan
- Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Andrew Thamboo
- Otolaryngology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Bozena Wrobel
- Otolaryngology, Keck School of Medicine, USC, Los Angeles, California, USA
| | - Carol H Yan
- Otolaryngology, School of Medicine, UCSD, La Jolla, California, USA
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7
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Jobin B, Zahal R, Bussières EL, Frasnelli J, Boller B. Olfactory Identification in Subjective Cognitive Decline: A Meta-Analysis. J Alzheimers Dis 2021; 79:1497-1507. [PMID: 33459721 DOI: 10.3233/jad-201022] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Recently, subjective cognitive decline (SCD) has been considered to be one of the first signs of Alzheimer's disease (AD). Since this potential early marker is sensitive but not specific to AD, combining it with other markers could ensure higher accuracy when predicting which persons with SCD will convert to AD. Since olfactory dysfunction is observable in both AD and mild cognitive impairment (MCI), it is a promising marker that could help improve the early diagnosis of AD. OBJECTIVE The aim of this meta-analysis was to verify whether the presence of SCD is associated with a decrease in olfactory identification ability. METHODS We collected articles from the following databases: PsychNet, PubMed, Ebsco, and ProQuest using the keywords: "SCD", "subjective cognitive decline", "subjective cognitive impairment", "subjective memory impairment", "subjective memory decline", "cognitive complaints", "memory complaints", "cognitive concerns", "memory concerns", "olfac*" and "smell". We included articles according to the following criteria: 1) participants aged 50 and over; 2) presence of an SCD group or a conceptual equivalent; 3) presence of a healthy control group with the same age range; and 4) assessment of olfactory identification ability. RESULTS Five studies met the inclusion criteria. Small and homogeneous effects were observed for olfactory identification alteration in individuals with SCD relative to controls (g = -0.16, 95% CI [-0.46, 0.14]). CONCLUSION Despite the low number of studies included, the findings suggest that odor identification is slightly altered in SCD compared to healthy older adults. This alteration in individuals with SCD could be an early marker of AD.
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Affiliation(s)
- Benoît Jobin
- Department of Psychology, Université du Québec à Trois-Rivières, QC, Canada.,Research Centre of the Hôpital du Sacré-Cœur de Montréal, QC, Canada.,Research Centre of the Institut Universitaire de Gériatrie de Montréal, QC, Canada
| | - Rayane Zahal
- Research Centre of the Hôpital du Sacré-Cœur de Montréal, QC, Canada.,Department of Psychology, Université de Montréal, QC, Canada
| | - Eve-Line Bussières
- Department of Psychology, Université du Québec à Trois-Rivières, QC, Canada
| | - Johannes Frasnelli
- Research Centre of the Hôpital du Sacré-Cœur de Montréal, QC, Canada.,Department of Anatomy, Université du Québec à Trois-Rivières, QC, Canada
| | - Benjamin Boller
- Department of Psychology, Université du Québec à Trois-Rivières, QC, Canada.,Research Centre of the Institut Universitaire de Gériatrie de Montréal, QC, Canada
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8
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Salehpour F, Hamblin MR, DiDuro JO. Rapid Reversal of Cognitive Decline, Olfactory Dysfunction, and Quality of Life Using Multi-Modality Photobiomodulation Therapy: Case Report. PHOTOBIOMODULATION PHOTOMEDICINE AND LASER SURGERY 2020; 37:159-167. [PMID: 31050946 DOI: 10.1089/photob.2018.4569] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Objective: We present a case report of reversal of cognitive impairment, olfactory dysfunction, and quality of life measures in a patient with cognitive decline after multi-modality photobiomodulation (PBM) therapy. Background: Transcranial and intranasal PBM has been introduced as a light-based therapeutic technique in which exposure to low levels of red to near-infrared (NIR) light stimulates neuronal function, leading to beneficial neurological effects. Materials and methods: Patient received twice-daily PBM therapy at home using three different wearable light-emitting diode (LED) devices. For the first week containing a mixture of continuous wave mode red (635 nm) and NIR (810 nm) LEDs, a prototype transcranial light helmet and a body pad were used. The body pad was placed on various areas on the lower back and the helmet was worn while seated. After the first week of treatment, an intranasal LED device, 10-Hz pulsed wave mode NIR (810 nm), was initiated in the left nostril twice daily. All three devices were applied simultaneously for an irradiation time of 25 min per session. Results: The patient showed a significant improvement in the Montreal Cognitive Assessment score from 18 to 24 and in the Working Memory Questionnaire score from 53 to 10. The cognitive enhancement was accompanied by reversal of olfactory dysfunction as measured by the Alberta Smell Test and peanut butter odor detection test. Quality-of-life measures improved and caregiver stress was reduced. No adverse effects were reported. Conclusions: PBM therapy may be a promising noninvasive approach for patients with neurodegenerative diseases.
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Affiliation(s)
- Farzad Salehpour
- 1 Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,2 Department of Medical Physics, Tabriz University of Medical Sciences, Tabriz, Iran.,3 ProNeuroLIGHT LLC, Phoenix, Arizona
| | - Michael R Hamblin
- 4 Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts.,5 Department of Dermatology, Harvard Medical School, Boston, Massachusetts.,6 Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts
| | - Joseph O DiDuro
- 3 ProNeuroLIGHT LLC, Phoenix, Arizona.,7 Neuropathy Treatment Centers of America LLC, Phoenix, Arizona
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9
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MacDonald SWS, Keller CJC, Brewster PWH, Dixon RA. Contrasting olfaction, vision, and audition as predictors of cognitive change and impairment in non-demented older adults. Neuropsychology 2019; 32:450-460. [PMID: 29809033 DOI: 10.1037/neu0000439] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE This study examines the relative utility of a particular class of noninvasive functional biomarkers-sensory functions-for detecting those at risk of cognitive decline and impairment. Three central research objectives were examined including whether (a) olfactory function, vision, and audition exhibited significant longitudinal declines in nondemented older adults; (b) multiwave change for these sensory function indicators predicted risk of mild cognitive impairment (MCI); and (c) change within persons for each sensory measure shared dynamic time-varying associations with within-person change in cognitive functioning. METHOD A longitudinal sample (n = 408) from the Victoria Longitudinal Study was assembled. Three cognitive status subgroups were identified: not impaired cognitively, single-assessment MCI, and multiple-assessment MCI. RESULTS We tested independent predictive associations, contrasting change in sensory function as predictors of cognitive decline and impairment, utilizing both linear mixed models and logistic regression analysis. Olfaction and, to a lesser extent, vision were identified as the most robust predictors of cognitive status and decline; audition showed little predictive influence. CONCLUSIONS These findings underscore the potential utility of deficits in olfactory function, in particular, as an early marker of age- and pathology-related cognitive decline. Functional biomarkers may represent potential candidates for use in the early stages of a multistep screening approach for detecting those at risk of cognitive impairment, as well as for targeted intervention. (PsycINFO Database Record
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Tahmasebi R, Zehetmayer S, Stögmann E, Lehrner J. Awareness of Olfactory Dysfunction in Subjective Cognitive Decline, Mild Cognitive Decline, and Alzheimer’s Disease. CHEMOSENS PERCEPT 2019. [DOI: 10.1007/s12078-019-09267-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Bower ES, Szajer J, Murphy C. Effect of Worry Level on Recall Memory for Odors in ApoE-ε4 Carriers and Non-Carriers. J Int Neuropsychol Soc 2019; 25:546-556. [PMID: 30987686 PMCID: PMC6534430 DOI: 10.1017/s1355617719000158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Increased levels of worry, age, and presence of the apolipoprotein-E (ApoE)-ε4 allele are associated with the risk of developing cognitive declines and Alzheimer's disease (AD). Odor memory performance has been shown to vary as a function of age and ApoE genotype, and odor memory tests are sensitive to preclinical AD. Worry is known to influence verbal memory; however, its effects on odor memory are unknown. This study aimed to assess the relationships between worry, age, and ε4 status on odor memory. METHOD Worry was evaluated for young (n = 53) and older (n = 45) adults using the Penn State Worry Questionnaire. Odor memory was assessed using the California Odor Learning Test, an olfactory analogue to the California Verbal Learning Test. RESULTS A significant main effect of worry on long-delay free recall was found, such that increasing worry was associated with better recall across age and ε4 status. A significant interaction effect between ε4 status and worry on both short-and long-delay cued recall was found, such that across age, higher worry was associated with increased cued recall scores among ε4-negative adults, and decreased scores among ε4-positive adults. CONCLUSIONS Findings demonstrated that worry influences odor memory and exerts a particular effect on cued recall among ε4 carriers who are at a greater risk of developing AD. Worry is a modifiable predictor of cognitive decline and risk of dementia in aging. Future studies on the effects of treatments aimed at reducing worry (e.g., cognitive behavioral therapies for anxiety) on changes in cognitive functioning are warranted.
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Affiliation(s)
- Emily S Bower
- Department of Psychology,San Diego State University,San Diego, California 92182,USA
| | - Jacquelyn Szajer
- SDSU/UCSD Joint Doctoral Program in Clinical Psychology,San Diego, California 92120,USA
| | - Claire Murphy
- Department of Psychology,San Diego State University,San Diego, California 92182,USA
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Park SJ, Lee JE, Lee KS, Kim JS. Comparison of odor identification among amnestic and non-amnestic mild cognitive impairment, subjective cognitive decline, and early Alzheimer’s dementia. Neurol Sci 2018; 39:557-564. [DOI: 10.1007/s10072-018-3261-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 01/22/2018] [Indexed: 12/21/2022]
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Goette W, Schmitt A, Clark A. Relationship between smell identification testing and the neuropsychological assessment of dementia in community-dwelling adults. APPLIED NEUROPSYCHOLOGY-ADULT 2017; 26:201-214. [PMID: 29182360 DOI: 10.1080/23279095.2017.1392303] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The objective of this research was to investigate the relationship of the University of Pennsylvania Smell Identification Test (UPSIT) with neuropsychological tests and identify the utility of the UPSIT in detecting cognitive impairment. This research was an archival study of neuropsychological test results obtained from 70 clients (30 male/40 female) of a community-based memory clinic. The sample had an average age of 69.7 (SD = 9.7) and education of 14.6 (SD = 2.8) years. Hypotheses were tested using correlations, receiver operating characteristic (ROC) curves, and logistic regression. The UPSIT showed significant, weak to moderate correlations with neuropsychological tests. The UPSIT raw score correlated significantly with all but one cognitive ability domain. The UPSIT T-score was significantly correlated with all cognitive domains. Obtained areas under the ROC curve (AUC) for the UPSIT ranged from .60 to .87. The AUCs of the UPSIT did not differ significantly from verbal semantic fluency tests, but the Repeatable Battery for the Assessment of Neuropsychological Status Total Scale and Delayed Memory index tended to produce larger AUCs than the UPSIT. Results from step-wise logistic regressions suggest that the UPSIT raw score provides unique information beyond its relationship to age. Olfaction relates broadly to cognitive ability and may be sensitive to early symptoms of cognitive decline. Further research is needed to explore the relationships between smell identification tests and neuropsychological assessment.
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Affiliation(s)
- William Goette
- a Department of Psychology and Counseling , University of Texas at Tyler , Tyler , Texas , USA
| | - Andrew Schmitt
- a Department of Psychology and Counseling , University of Texas at Tyler , Tyler , Texas , USA
| | - Avery Clark
- a Department of Psychology and Counseling , University of Texas at Tyler , Tyler , Texas , USA
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Hu B, Geng C, Hou XY. Oligomeric amyloid-β peptide disrupts olfactory information output by impairment of local inhibitory circuits in rat olfactory bulb. Neurobiol Aging 2016; 51:113-121. [PMID: 28061384 DOI: 10.1016/j.neurobiolaging.2016.12.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 11/22/2016] [Accepted: 12/05/2016] [Indexed: 11/27/2022]
Abstract
Although early olfactory dysfunction has been found in patients with Alzheimer's disease, the underlying mechanisms remain unclear. In this study, we investigated whether and how oligomeric amyloid-β peptide (Aβ) affects the responses of mitral cells (MCs). We found that oligomeric Aβ1-42 increased spontaneous and evoked firing rates but decreased the ratio of evoked to spontaneous firings in MCs. Aβ1-42 oligomers showed no impact on the hyperactivity exerted by pharmacological blockage of GABAA receptors, suggesting an involvement of GABAergic inhibitory transmission in Aβ1 to 42-induced over-excitability. It was further determined that Aβ1-42 oligomers inhibited the frequency of spontaneous inhibitory postsynaptic currents and miniature inhibitory postsynaptic currents, as well as the amplitude of miniature inhibitory postsynaptic currents in MCs. Both recurrent and lateral inhibition of MCs, which are critical for odor discrimination, were also disrupted by Aβ1-42 oligomers. The above data indicate that Aβ impairs local inhibitory circuits and thereby leads to perturbations of olfactory information output in the olfactory bulb. This study reveals a cellular and synaptic basis of olfactory deficits associated with Alzheimer's disease.
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Affiliation(s)
- Bin Hu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Nanjing Medical University, Jiangsu, China; Jiangsu Key Laboratory of Brain Disease Bioinformation, Xuzhou Medical University, Jiangsu, China; Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Jiangsu, China
| | - Chi Geng
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Xuzhou Medical University, Jiangsu, China; Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Jiangsu, China
| | - Xiao-Yu Hou
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Nanjing Medical University, Jiangsu, China; Jiangsu Key Laboratory of Brain Disease Bioinformation, Xuzhou Medical University, Jiangsu, China; Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Jiangsu, China.
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Ward AM, Calamia M, Thiemann E, Dunlap J, Tranel D. Association between olfaction and higher cortical functions in Alzheimer's disease, mild cognitive impairment, and healthy older adults. J Clin Exp Neuropsychol 2016; 39:646-658. [PMID: 27868477 DOI: 10.1080/13803395.2016.1253667] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Neural regions important for smell are proximal and closely connected to cortical areas that have been strongly implicated in higher order functions of value-based decision making and emotional memory. The integrity of these neural regions are affected in aging and neurodegenerative conditions. Two specific predictions follow from these neuroanatomical arrangements-namely, that olfaction would be associated with value-based decision making and with emotional memory. METHOD To test these predictions, we measured these different capacities in participants with presumed varying degrees of integrity of the relevant brain structures: specifically, 13 patients with Alzheimer's disease, 8 patients with mild cognitive impairment, and 20 healthy older adults. The participants completed detailed tests of olfaction, value-based decision making, emotional memory, and general cognitive ability. RESULTS Olfactory functioning was significantly associated with emotional and nonemotional memory. The association was especially strong and consistent for memory recall with olfaction, explaining as much as 10% additional variance over and above general cognition. Olfactory functioning was not strongly or consistently associated with decision making over and above general cognition. CONCLUSION Olfaction is a strong predictor of memory recall. These findings may contribute to a better understanding of olfaction and specific cognitive domains known to be affected by aging and implicated in neurodegenerative disease.
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Affiliation(s)
- Amanda M Ward
- a Department of Psychological and Brain Sciences , University of Iowa , Iowa City , IA , USA
| | - Matthew Calamia
- b Department of Psychology , Louisiana State University , Baton Rouge , LA , USA
| | - Erin Thiemann
- a Department of Psychological and Brain Sciences , University of Iowa , Iowa City , IA , USA
| | - Jamie Dunlap
- a Department of Psychological and Brain Sciences , University of Iowa , Iowa City , IA , USA
| | - Daniel Tranel
- a Department of Psychological and Brain Sciences , University of Iowa , Iowa City , IA , USA.,c Department of Neurology , University of Iowa Carver College of Medicine , Iowa City , IA , USA
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Xu ZP, Yang SL, Zhao S, Zheng CH, Li HH, Zhang Y, Huang RX, Li MZ, Gao Y, Zhang SJ, Zhan PY, Zhang LF, Deng L, Wei S, Liu YC, Ye JW, Ren HJ, Li N, Kong CX, Wang X, Fang L, Zhou QZ, Jiang HW, Li JR, Wang Q, Ke D, Liu GP, Wang JZ. Biomarkers for Early Diagnostic of Mild Cognitive Impairment in Type-2 Diabetes Patients: A Multicentre, Retrospective, Nested Case-Control Study. EBioMedicine 2016; 5:105-13. [PMID: 27077117 PMCID: PMC4816853 DOI: 10.1016/j.ebiom.2016.02.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 02/05/2016] [Accepted: 02/05/2016] [Indexed: 12/12/2022] Open
Abstract
Background Both type 2 diabetes mellitus (T2DM) and Alzheimer's disease (AD) are common age-associated disorders and T2DM patients show an increased risk to suffer from AD, however, there is currently no marker to identify who in T2DM populations will develop AD. Since glycogen synthase kinase-3β (GSK-3β) activity, ApoE genotypes and olfactory function are involved in both T2DM and AD pathogenesis, we investigate whether alterations of these factors can identify cognitive impairment in T2DM patients. Methods The cognitive ability was evaluated using Minimum Mental State Examination (MMSE) and Clinical Dementia Rating (CDR), and the mild cognitive impairment (MCI) was diagnosed by Petersen's criteria. GSK-3β activity in platelet, ApoE genotypes in leucocytes and the olfactory function were detected by Western/dot blotting, the amplification refractory mutation system (ARMS) PCR and the Connecticut Chemosensory Clinical Research Center (CCCRC) test, respectively. The odds ratio (OR) and 95% confidence intervals (95% CI) of the biomarkers for MCI diagnosis were calculated by logistic regression. The diagnostic capability of the biomarkers was evaluated by receiver operating characteristics (ROC) analyses. Findings We recruited 694 T2DM patients from Jan. 2012 to May. 2015 in 5 hospitals (Wuhan), and 646 of them met the inclusion criteria and were included in this study. 345 patients in 2 hospitals were assigned to the training set, and 301 patients in another 3 hospitals assigned to the validation set. Patients in each set were randomly divided into two groups: T2DM without MCI (termed T2DM-nMCI) or with MCI (termed T2DM-MCI). There were no significant differences for sex, T2DM years, hypertension, hyperlipidemia, coronary disease, complications, insulin treatment, HbA1c, ApoE ε2, ApoE ε3, tGSK3β and pS9GSK3β between the two groups. Compared with the T2DM-nMCI group, T2DM-MCI group showed lower MMSE score with older age, ApoE ε4 allele, higher olfactory score and higher rGSK-3β (ratio of total GSK-3β to Ser9-phosphorylated GSK-3β) in the training set and the validation set. The OR values of age, ApoE ε4 gene, olfactory score and rGSK-3β were 1.09, 2.09, 1.51, 10.08 in the training set, and 1.06, 2.67, 1.47, 7.19 in the validation set, respectively. The diagnostic accuracy of age, ApoE ε4 gene, olfactory score and rGSK-3β were 0.76, 0.72, 0.66, 0.79 in the training set, and 0.70, 0.68, 0.73, 0.79 in the validation set, respectively. These four combined biomarkers had the area under the curve (AUC) of 82% and 86%, diagnostic accuracy of 83% and 81% in the training set and the validation set, respectively. Interpretation Aging, activation of peripheral circulating GSK-3β, expression of ApoE ε4 and increase of olfactory score are diagnostic for the mild cognitive impairment in T2DM patients, and combination of these biomarkers can improve the diagnostic accuracy. ApoE ε4 gene, platelet GSK-3β activation, olfactory dysfunction and aging are non-invasive, affordable and accessible biomarkers for diagnosing mild cognitive impairment in type 2 diabetes mellitus patients, and the combination of these non-invasive, affordable and accessible biomarkers can improve the accuracy of the diagnosis.
Epidemiological studies show that type 2 diabetes mellitus is an independent risk factor of Alzheimer disease, and a large proportion of diabetic patients will develop Alzheimer disease, but no early diagnostic tool to identify them. We find that ApoE ε4 gene, platelet GSK-3β activation, olfactory dysfunction and aging are early markers for dementia in type 2 diabetes patients, and combination of these non-invasive markers can improve the diagnostic accuracy. These findings shed light on the early identification in type 2 diabetes population who will develop Alzheimer disease and thus enable early intervention to this currently incurable neurodegenerative disorder.
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Key Words
- AD, Alzheimer's disease
- ARMS, amplification refractory mutation system
- AUC, the area under the curve
- Alzheimer's disease
- ApoE gene
- ApoE, apolipoprotein E
- CCCRC, Connecticut Chemosensory Clinical Research Center
- CDR, clinical dementia rating
- CI, confidence intervals
- GSK-3β, glycogen synthase kinase-3β
- Glycogen synthase kinase-3β
- HbA1c, hemoglobin A1c
- MCI, mild cognitive impairment
- MMSE, minimum mental state examination
- Mild cognitive impairment
- OR, odds ratio
- Olfactory score
- ROC, receiver operating characteristics
- T2DM, type 2 diabetes mellitus
- Type 2 diabetes mellitus
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Affiliation(s)
- Zhi-Peng Xu
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; Department of Neurology, Wuhan General Hospital of Guangzhou Command, Wuhan 430070, China
| | - Su-Lian Yang
- School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Shi Zhao
- Department of Endocrinology, The Central Hospital of Wuhan, Wuhan 430014, China
| | - Cheng-Hong Zheng
- Department of Endocrinology, Wuhan Hospital of Traditional Chinese Medicine, Wuhan 430014, China
| | - Hong-Hua Li
- Department of Neurology, Wuhan General Hospital of Guangzhou Command, Wuhan 430070, China
| | - Yao Zhang
- Li-Yuan Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430077, China
| | - Rong-Xi Huang
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Meng-Zhu Li
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yuan Gao
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Shu-Juan Zhang
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Pei-Yan Zhan
- Department of Neurology, The Central Hospital of Wuhan, Wuhan 430014, China
| | - Li-Fang Zhang
- Department of Endocrinology, Wuhan Hospital of Traditional Chinese Medicine, Wuhan 430014, China
| | - Lin Deng
- Department of Endocrinology, The Central Hospital of Wuhan, Wuhan 430014, China
| | - Sheng Wei
- School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yan-Chao Liu
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Jing-Wang Ye
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Hu-Jun Ren
- Department of Endocrinology, Wuhan General Hospital of Guangzhou Command, Wuhan 430070, China
| | - Na Li
- Department of Endocrinology, The Central Hospital of Wuhan, Wuhan 430014, China
| | - Cai-Xia Kong
- Department of Endocrinology, The First Hospital of Wuhan, Wuhan 430022, China
| | - Xin Wang
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Lin Fang
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Qiu-Zhi Zhou
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Hong-Wei Jiang
- School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Jing-Rong Li
- Health Service Center of Jianghan District, Wuhan 430014, China
| | - Qun Wang
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226000, China
| | - Dan Ke
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226000, China
| | - Gong-Ping Liu
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226000, China
| | - Jian-Zhi Wang
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226000, China
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Abstract
Alzheimer's disease (AD) is a common neurodegenerative disorder with the earliest clinical symptom of olfactory dysfunction, which is a potential clinical marker for AD severity and progression. However, many questions remain unanswered. This article reviews relevant research on olfactory dysfunction in AD and evaluates the predictive value of olfactory dysfunction for the epidemiological, pathophysiological, and clinical features of AD, as well as for the conversion of cognitive impairment to AD. We summarize problems of existing studies and provide a useful reference for further studies in AD olfactory dysfunction and for clinical applications of olfactory testing.
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Affiliation(s)
- Yong-Ming Zou
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, People's Republic of China
| | - Da Lu
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, People's Republic of China
| | - Li-Ping Liu
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, People's Republic of China
| | - Hui-Hong Zhang
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, People's Republic of China
| | - Yu-Ying Zhou
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, People's Republic of China
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Dong J, Yang J, Tranah G, Franceschini N, Parimi N, Alkorta-Aranburu G, Xu Z, Alonso A, Cummings SR, Fornage M, Huang X, Kritchevsky S, Liu Y, London S, Niu L, Wilson RS, De Jager PL, Yu L, Singleton AB, Harris T, Mosley TH, Pinto JM, Bennett DA, Chen H. Genome-wide Meta-analysis on the Sense of Smell Among US Older Adults. Medicine (Baltimore) 2015; 94:e1892. [PMID: 26632684 PMCID: PMC5058953 DOI: 10.1097/md.0000000000001892] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 09/04/2015] [Accepted: 09/29/2015] [Indexed: 11/25/2022] Open
Abstract
Olfactory dysfunction is common among older adults and affects their safety, nutrition, quality of life, and mortality. More importantly, the decreased sense of smell is an early symptom of neurodegenerative diseases such as Parkinson disease (PD) and Alzheimer disease. However, the genetic determinants for the sense of smell have been poorly investigated. We here performed the first genome-wide meta-analysis on the sense of smell among 6252 US older adults of European descent from the Atherosclerosis Risk in Communities (ARIC) study, the Health, Aging, and Body Composition (Health ABC) study, and the Religious Orders Study and the Rush Memory and Aging Project (ROS/MAP). Genome-wide association study analysis was performed first by individual cohorts and then meta-analyzed using fixed-effect models with inverse variance weights. Although no SNPs reached genome-wide statistical significance, we identified 13 loci with suggestive evidence for an association with the sense of smell (Pmeta < 1 × 10). Of these, 2 SNPs at chromosome 17q21.31 (rs199443 in NSF, P = 3.02 × 10; and rs2732614 in KIAA1267-LRRC37A, P = 6.65 × 10) exhibited cis effects on the expression of microtubule-associated protein tau (MAPT, 17q21.31) in 447 frontal-cortex samples obtained postmortem and profiled by RNA-seq (P < 1 × 10). Gene-based and pathway-enrichment analyses further implicated MAPT in regulating the sense of smell in older adults. Similar results were obtained after excluding participants who reported a physician-diagnosed PD or use of PD medications. In conclusion, we provide preliminary evidence that the MAPT locus may play a role in regulating the sense of smell in older adults and therefore offer a potential genetic link between poor sense of smell and major neurodegenerative diseases.
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Affiliation(s)
- Jing Dong
- From the Epidemiology Branch (JD, ZX, SL, HC) and Biostatistics Branch (LN), National Institute of Environmental Health Sciences, Research Triangle Park, NC; Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL (JY, RSW, LY, DAB); California Pacific Medical Center Research Institute, San Francisco, CA (GT, NP, SC); Department of Epidemiology, University of North Carolina Gillings School of Global Public Health, Chapel Hill, NC (NF); Department of Human Genetics, University of Chicago, Chicago, IL (GA-A); Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN (AA); Institute of Molecular Medicine and Human Genetics Center, University of Texas Health Science Center at Houston, Houston, TX (MF); Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA (XH); Sticht Center on Aging (SK) and Division of Public Health Sciences (YL), Wake Forest School of Medicine, Winston-Salem, NC; Program in Translational Neuro Psychiatric Genomics, Departments of Neurology and Psychiatry, Institute for the Neurosciences, Brigham and Women's Hospital; Harvard Medical School; Program in Medical and Population Genetics, Broad Institute, Boston, MA (PLD); Laboratory of Neurogenetics (ABS) and Laboratory of Epidemiology, Demography, and Biometry (TH), National Institute on Aging, Bethesda, MD; Division of Geriatrics, Department of Medicine, University of Mississippi Medical Center, Jackson, MS (THM); Section of Otolaryngology-Head and Neck Surgery, Department of Surgery, The University of Chicago Medicine and Biological Sciences, Chicago, IL (JMP); Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA (JY, LY, DAB); and Departments of Neurological Sciences and Behavioral Sciences, Rush University Medical Center, Chicago, IL, USA (RSW)
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Abstract
PURPOSE OF REVIEW To provide an update of the recent studies on the olfactory function in Alzheimer's disease, with a focus on the olfactory identification function. RECENT FINDINGS The studies reviewed here confirm previous reports on the poor olfactory function in Alzheimer's disease compared to health normal controls and also as a marker for conversion from mild cognitive impairment to Alzheimer's disease. Olfactory identification function has been associated with severity of illness, non-cognitive neuropsychiatric symptoms, and structural and functional MRI measures. There is a possible interaction of apolipoprotein E genotype with olfactory performance in Alzheimer's disease patients and those at risk for Alzheimer's disease. Usefulness of smell identification function in differentiating Alzheimer's disease patients from other types of dementia needs to be established. SUMMARY The need for simple, inexpensive and non-invasive procedures for aiding in the diagnosis and understanding of Alzheimer's disease has led to theories and procedures examining the role of olfactory functions in Alzheimer's disease. Although there is increasing evidence for olfactory dysfunction in general and impaired odour identification in particular in Alzheimer's disease, additional larger and methodologically sound research is needed for testing its clinical utility in day-to-day clinical practice for early, accurate and differential diagnosis of Alzheimer's disease.
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Vyhnalek M, Magerova H, Andel R, Nikolai T, Kadlecova A, Laczo J, Hort J. Olfactory identification in amnestic and non-amnestic mild cognitive impairment and its neuropsychological correlates. J Neurol Sci 2015; 349:179-84. [DOI: 10.1016/j.jns.2015.01.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 01/07/2015] [Accepted: 01/08/2015] [Indexed: 01/16/2023]
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Caravaglios G, Muscoso EG, Di Maria G, Costanzo E. Patients with mild cognitive impairment have an abnormal upper-alpha event-related desynchronization/synchronization (ERD/ERS) during a task of temporal attention. J Neural Transm (Vienna) 2014; 122:441-53. [PMID: 24947877 DOI: 10.1007/s00702-014-1262-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 06/11/2014] [Indexed: 10/25/2022]
Abstract
There are several evidences indicating that an impairment in attention-executive functions is present in prodromal Alzheimer's disease and predict future global cognitive decline. In particular, the issue of temporal orienting of attention in patients with mild cognitive impairment (MCI) due to Alzheimer's disease has been overlooked. The present research aimed to explore whether subtle deficits of cortical activation are present in these patients early in the course of the disease. We studied the upper-alpha event-related synchronization/desynchronization phenomenon during a paradigm of temporal orientation of attention. MCI patients (n = 27) and healthy elderly controls (n = 15) performed a task in which periodically omitted tones had to be predicted and their virtual onset time had to be marked by pressing a button. Single-trial responses were measured, respectively, before and after the motor response. Then, upper-alpha responses were compared to upper-alpha power during eyes-closed resting state. The time course of the task was characterized by two different behavioral conditions: (1) a pre-event epoch, in which the subject awaited the virtual onset of the omitted tone, (2) a post-event epoch (after button pressing), in which the subject was in a post-motor response condition. The principal findings are: (1) during the waiting epoch, only healthy elderly had an upper-alpha ERD at the level of both temporal and posterior brain regions; (2) during the post-motor epoch, the aMCI patients had a weaker upper-alpha ERS on prefrontal regions; (3) only healthy elderly showed a laterality effect: (a) during the waiting epoch, the upper-alpha ERD was greater at the level of the right posterior-temporal lead; during the post-motor epoch, the upper alpha ERS was greater on the left prefrontal lead. The relevance of these findings is that the weaker upper-alpha response observed in aMCI patients is evident even if the accuracy of the behavioral performance (i.e., button pressing) is still spared. This abnormal upper-alpha response might represent an early biomarker of the attention-executive network impairment in MCI due to Alzheimer's disease.
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Affiliation(s)
- Giuseppe Caravaglios
- Azienda Ospedaliera Cannizzaro, U.O.C. di Neurologia, Via Messina, 829, 95126, Catania, Italy,
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23
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Denzer MY, Gailer S, Kern DW, Schumm LP, Thuerauf N, Kornhuber J, Buettner A, Beauchamp J. Quantitative Validation of the n-Butanol Sniffin' Sticks Threshold Pens. CHEMOSENS PERCEPT 2014; 7:91-101. [PMID: 24883171 PMCID: PMC4037591 DOI: 10.1007/s12078-014-9168-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 04/01/2014] [Indexed: 11/30/2022]
Abstract
Odorant pens are used by medical practitioners and researchers to assess olfactory dysfunction. Despite their routine use, there are currently no data on the gas-phase odorant concentrations released from the pen tips or whether these concentrations scale linearly with the aqueous-phase concentrations inside the pens. The commercially available Sniffin' Sticks odor threshold test containing n-butanol was chosen for evaluation. The gas-phase concentration of n-butanol at the tip of each pen was measured directly in a new set of pens via proton-transfer-reaction mass spectrometry (PTR-MS). Measurements were additionally made on the same pens after 6 months and two older pen sets, namely a 3-year-old (used) and 4-year-old (new) set. Furthermore, application-related tests were made to determine the performance of the pens during routine use and under stress. These data demonstrate that the gas-phase n-butanol concentrations of the threshold pens are linear over the entire set, both for brand-new pens and 6 months later; this reflects the expected performance that was previously only assumed. Furthermore, the application-simulation tests demonstrated a good performance of the pens when used according to their intended protocol. Measurements of the older pen sets suggest that storage conditions are more critical than usage for pen stability. The present findings confirm that the n-butanol odorant pens are an appropriate tool for threshold testing, provided they are stored and handled correctly. Figureᅟ
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Affiliation(s)
- Melanie Y. Denzer
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestraße 9, 91054 Erlangen, Germany
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Stefan Gailer
- Department of Sensory Analytics, Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Strasse 35, 85354 Freising, Germany
| | - David W. Kern
- Department of Comparative Human Development, and The Institute for Mind and Biology, The University of Chicago, 940 E 57th St., Chicago, IL USA
| | - L. Philip Schumm
- Department of Health Studies, The University of Chicago, 5841 South Maryland Ave., MC2007, Chicago, IL USA
| | - Norbert Thuerauf
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Andrea Buettner
- Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestraße 9, 91054 Erlangen, Germany
- Department of Sensory Analytics, Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Strasse 35, 85354 Freising, Germany
| | - Jonathan Beauchamp
- Department of Sensory Analytics, Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Strasse 35, 85354 Freising, Germany
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Olfactory Dysfunction in the Elderly: Basic Circuitry and Alterations with Normal Aging and Alzheimer's Disease. CURRENT GERIATRICS REPORTS 2014; 3:91-100. [PMID: 25045620 DOI: 10.1007/s13670-014-0080-y] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Preclinical detection of Alzheimer disease is critical to determining at-risk individuals in order to improve patient and caregiver planning for their futures and to identify individuals likely to benefit from treatment as advances in therapeutics develop over time. Identification of olfactory dysfunction at the preclinical and early stages of the disease is a potentially useful method to accomplish these goals. We first review basic olfactory circuitry. We then evaluate the evidence of pathophysiological change in the olfactory processing pathways during aging and Alzheimer disease in both human and animal models. We also review olfactory behavioral studies during these processes in both types of models. In doing so, we suggest hypotheses about the localization and mechanisms of olfactory dysfunction and identify important avenues for future work.
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25
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Attems J, Walker L, Jellinger KA. Olfactory bulb involvement in neurodegenerative diseases. Acta Neuropathol 2014; 127:459-75. [PMID: 24554308 DOI: 10.1007/s00401-014-1261-7] [Citation(s) in RCA: 224] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 02/11/2014] [Accepted: 02/11/2014] [Indexed: 12/24/2022]
Abstract
Olfactory dysfunction is a common and early symptom of many neurodegenerative diseases, particularly of Parkinson's disease and other synucleinopathies, Alzheimer's disease (AD), and mild cognitive impairment heralding its progression to dementia. The neuropathologic changes of olfactory dysfunction in neurodegenerative diseases may involve the olfactory epithelium, olfactory bulb/tract, primary olfactory cortices, and their secondary targets. Olfactory dysfunction is related to deposition of pathological proteins, α-synuclein, hyperphosphorylated tau protein, and neurofilament protein in these areas, featured by neurofibrillary tangles, Lewy bodies and neurites inducing a complex cascade of molecular processes including oxidative damage, neuroinflammation, and cytosolic disruption of cellular processes leading to cell death. Damage to cholinergic, serotonergic, and noradrenergic systems is likely involved, since such damage is most marked in those diseases with severe anosmia. Recent studies of olfactory dysfunction have focused its potential as an early biomarker for the diagnosis of neurodegenerative disorders and their disease progression. Here, we summarize the current knowledge on neuropathological and pathophysiological changes of the olfactory system in the most frequent neurodegenerative diseases, in particular AD and synucleinopathies. We also present neuropathological findings in the olfactory bulb and tract in a large autopsy cohort (n = 536, 57.8 % female, mean age 81.3 years). The severity of olfactory bulb HPτ, Aβ, and αSyn pathology correlated and increased significantly (P < 0.001) with increasing neuritic Braak stages, Thal Aβ phases, and cerebral Lewy body pathology, respectively. Hence, further studies are warranted to investigate the potential role of olfactory biopsies (possibly restricted to the olfactory epithelium) in the diagnostic process of neurodegenerative diseases in particular in clinical drug trials to identify subjects showing early, preclinical stages of neurodegeneration and to stratify clinically impaired cohorts according to the underlying cerebral neuropathology.
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Affiliation(s)
- Johannes Attems
- Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne, UK
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26
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Seligman SC, Kamath V, Giovannetti T, Arnold SE, Moberg PJ. Olfaction and apathy in Alzheimer's disease, mild cognitive impairment, and healthy older adults. Aging Ment Health 2013; 17:564-70. [PMID: 23398350 PMCID: PMC3664659 DOI: 10.1080/13607863.2013.768208] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVES Apathy is a prevalent neuropsychiatric manifestation in individuals with Alzheimer's disease (AD) that is associated with decreased social functioning and increased caregiver burden. Olfactory deficits are also commonly observed in AD, and prior work has indicated a link between increased apathy and olfactory dysfunction in individuals with Parkinson's disease. Here, we examined odor identification performance in patients with probable AD (n = 172), individuals with mild cognitive impairment (MCI; n = 112), and neurologically and psychiatrically healthy older adults (n = 132) and its relation to apathy, depression, and overall psychopathology. METHOD Participants were administered the Sniffin' Sticks odor identification test and measures assessing severity of apathy, depression, and overall neuropsychiatric symptomatology. RESULTS Consistent with previous research, AD and MCI patients were significantly worse at identifying odors than healthy older adults. Additionally, a sex by diagnosis interaction was observed. AD patients had significantly higher levels of apathy relative to MCI and control participants. Of note, across the entire sample odor identification deficits were correlated with level of apathy at the level of p < 0.01, but not with depression or neuropsychiatric symptom severity, when controlling for Mini-Mental State Examination (MMSE) score. CONCLUSION Collectively, these data suggest that olfactory disturbance and apathy in AD may result from the progression of disease pathology in shared neural substrates.
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Affiliation(s)
- Sarah C. Seligman
- Department of Psychology, Temple University, Philadelphia, PA, USA,Manuscript Submission Correspondence to: Sarah Seligman, Department of Psychology, Temple University, 1701 N. 13th Street, 6th Floor Weiss Hall, Philadelphia, PA 19122. Telephone: 914.450.2065.
| | - Vidyulata Kamath
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA,Smell and Taste Center, Department of Otorhinolaryngology: Head & Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA,Data Correspondence to: Vidya Kamath, Ph.D., Neuropsychiatry Section, Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, 3400 Spruce Street, 10th Floor – Gates Building, Philadelphia, PA 19104. Telephone: 215.839.9193. Fax: 215.662.7903.
| | | | - Steven E. Arnold
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA,Smell and Taste Center, Department of Otorhinolaryngology: Head & Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA,Alzheimer’s Disease Core Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA,Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Paul J. Moberg
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA,Smell and Taste Center, Department of Otorhinolaryngology: Head & Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA,Alzheimer’s Disease Core Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA,Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
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27
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Knaapila A, Tuorila H. Experiences of environmental odors among self-reported hyperosmics: a pilot study. J Health Psychol 2013; 19:897-906. [PMID: 23520356 DOI: 10.1177/1359105313481080] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We investigated everyday odor experiences in 55 people (14-75 years old) who rated their sense of smell as far better than average. Compared to 55 gender- and age-matched controls, the self-reported hyperosmics scored higher on the Affective Impact of Odor Scale, rated negative consequences and unpleasant memories due to odors as more likely, rated environmental odors as more annoying, reported increased sensitivity to specific odors more frequently, paid more attention to odors, and agreed more strongly that their sense of smell has caused inconvenience to them. Based on these data, subjective hyperosmia is associated with primarily negative odor-related experiences.
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Affiliation(s)
- Antti Knaapila
- University of Helsinki, Finland University of Turku, Finland
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28
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Sohrabi HR, Bates KA, Weinborn MG, Johnston ANB, Bahramian A, Taddei K, Laws SM, Rodrigues M, Morici M, Howard M, Martins G, Mackay-Sim A, Gandy SE, Martins RN. Olfactory discrimination predicts cognitive decline among community-dwelling older adults. Transl Psychiatry 2012; 2:e118. [PMID: 22832962 PMCID: PMC3365262 DOI: 10.1038/tp.2012.43] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The presence of olfactory dysfunction in individuals at higher risk of Alzheimer's disease has significant diagnostic and screening implications for preventive and ameliorative drug trials. Olfactory threshold, discrimination and identification can be reliably recorded in the early stages of neurodegenerative diseases. The current study has examined the ability of various olfactory functions in predicting cognitive decline in a community-dwelling sample. A group of 308 participants, aged 46-86 years old, were recruited for this study. After 3 years of follow-up, participants were divided into cognitively declined and non-declined groups based on their performance on a neuropsychological battery. Assessment of olfactory functions using the Sniffin' Sticks battery indicated that, contrary to previous findings, olfactory discrimination, but not olfactory identification, significantly predicted subsequent cognitive decline (odds ratio = 0.869; P<0.05; 95% confidence interval = 0.764-0.988). The current study findings confirm previously reported associations between olfactory and cognitive functions, and indicate that impairment in olfactory discrimination can predict future cognitive decline. These findings further our current understanding of the association between cognition and olfaction, and support olfactory assessment in screening those at higher risk of dementia.
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Affiliation(s)
- H R Sohrabi
- The School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia,The McCusker Alzheimer's Research Foundation, Hollywood Private Hospital, Nedlands, WA, Australia,The Centre of Excellence for Alzheimer's Disease Research and Care, Edith Cowan University, Joondalup, WA, Australia
| | - K A Bates
- The McCusker Alzheimer's Research Foundation, Hollywood Private Hospital, Nedlands, WA, Australia,The Centre of Excellence for Alzheimer's Disease Research and Care, Edith Cowan University, Joondalup, WA, Australia,The School of Animal Biology, University of Western Australia, Crawley, WA, Australia
| | - M G Weinborn
- The School of Psychology, University of Western Australia, Crawley, WA, Australia
| | - A N B Johnston
- Eskitis Institute for Cell and Molecular Therapies, Griffith University, Nathan, Queensland, Australia
| | - A Bahramian
- The McCusker Alzheimer's Research Foundation, Hollywood Private Hospital, Nedlands, WA, Australia
| | - K Taddei
- The School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia,The McCusker Alzheimer's Research Foundation, Hollywood Private Hospital, Nedlands, WA, Australia,The Centre of Excellence for Alzheimer's Disease Research and Care, Edith Cowan University, Joondalup, WA, Australia
| | - S M Laws
- The School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia,The McCusker Alzheimer's Research Foundation, Hollywood Private Hospital, Nedlands, WA, Australia,The Centre of Excellence for Alzheimer's Disease Research and Care, Edith Cowan University, Joondalup, WA, Australia
| | - M Rodrigues
- The School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia,The McCusker Alzheimer's Research Foundation, Hollywood Private Hospital, Nedlands, WA, Australia
| | - M Morici
- The School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia
| | - M Howard
- The School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia
| | - G Martins
- The School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia,The McCusker Alzheimer's Research Foundation, Hollywood Private Hospital, Nedlands, WA, Australia
| | - A Mackay-Sim
- Eskitis Institute for Cell and Molecular Therapies, Griffith University, Nathan, Queensland, Australia
| | - S E Gandy
- Mount Sinai School of Medicine, New York, NY, USA
| | - R N Martins
- The School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia,The McCusker Alzheimer's Research Foundation, Hollywood Private Hospital, Nedlands, WA, Australia,The Centre of Excellence for Alzheimer's Disease Research and Care, Edith Cowan University, Joondalup, WA, Australia,The School of Psychiatry and Clinical Neuroscience, University of Western Australia, Crawley, WA, Australia,The School of Medical Sciences, Edith Cowan University, 270 Joondalup Dr, Joondalup, WA 6027, Australia. E-mail:
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Walla P, Duregger C, Deecke L, Dal-Bianco P. Dysfunctional Incidental Olfaction in Mild Cognitive Impairment (MCI): An Electroencephalography (EEG) Study. Brain Sci 2011; 1:3-15. [PMID: 24962612 PMCID: PMC4061781 DOI: 10.3390/brainsci1010003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 09/27/2011] [Accepted: 10/18/2011] [Indexed: 10/31/2022] Open
Abstract
Our study provides evidence that Mild Cognitive Impairment (MCI) is associated with olfactory dysfunction on both conscious and non-conscious levels. MCI patients and age-matched controls underwent a face processing task during which sympathy decisions had to be made via button presses. Incidentally, some of the faces were associated with a simultaneously presented odour. Although attention was paid to faces, brain activities were analysed with respect to odour versus no-odour conditions. Behavioural differences were found related to overall face recognition performance, but these were not statistically significant. However, odour-related neurophysiology differed between both groups. Normal controls demonstrated brain activity differences between odour and no-odour conditions that resemble difference activity patterns in healthy young participants as described in a previous magnetoencephalography (MEG) study [1]. They showed odour-related activity patterns between about 160 ms and 320 ms after stimulus onset and between about 640 ms and 720 ms. On the other hand, the patient group did not show any such difference activities. Based on previous research we interpret the early odour-related brain activity pattern in controls as being associated with subliminal olfaction and the later activity pattern with conscious olfaction. None of these were found in MCI patients, although it has to be emphasised that our sample size was rather small. We confirm previous findings about olfactory related dysfunction in patients with MCI and conclude from our findings that even subliminal odour-related information processing is impaired.
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Affiliation(s)
- Peter Walla
- School of Psychology, Faculty of Science and Information Technology, University of Newcastle, Callaghan 2308 NSW, Australia.
| | - Cornelia Duregger
- School of Psychology, Faculty of Science and Information Technology, University of Newcastle, Callaghan 2308 NSW, Australia.
| | - Lüder Deecke
- Department of Clinical Neurology, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
| | - Peter Dal-Bianco
- Department of Clinical Neurology, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
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Abstract
AbstractResearch results indicate systemic odor identification deficits in patients with Alzheimer’s disease (AD). The aims of this study were: 1) to compare the ability to identify different odors and to compare cognitive status among patients with AD, patients with vascular dementia (VaD) and a comparison group of elderly persons; 2) to test the efficiency of olfactory and neuropsychological measures to classify patients and 3) to relate the odor identification ability with cognitive functioning for each group, respectively. The participants were 15 patients with AD, 11 patients with VaD and 30 non-demented elderly persons, age range 58 to 90. To assess olfactory function, we used the Scandinavian Odor-Identification Test. To assess cognitive functions, we used the Dementia Rating Scale-2, the Clock Drawing Test, the Boston Naming Test and the Category Fluency Test. The ANOVA showed that patients with AD correctly identifed significantly fewer odors presented to them compared to patients with VaD and control group. Patients with AD achieved significantly lower scores on all neuropsychological measures compared to the control group and differ in the DRS-2 total score, initiation/perseveration, constructive and naming abilities comparing to patients with VaD. Discriminant analysis showed that category fluency and olfactory identification were the best predictors of AD. Significant correlations were found between the olfactory and initiation/perseveration, memory and animal naming abilities for patients with AD. Differences among patients with AD, VaD and elderly persons exist in their abilities to identify odors. The findings suggest that olfactory functional testing in combination with memory testing are important.
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