Anosmia is very common in the Lewy body variant of Alzheimer's disease

Olichney, J. M.; Murphy, C.; Hofstetter, C. R.; Foster, K.; Hansen, L. A.; Thal, L. J.; Katzman, R.
October 2005
Journal of Neurology, Neurosurgery & Psychiatry;Oct2005, Vol. 76 Issue 10, p1342
Academic Journal
journal article
Background: Olfactory abnormalities are reported in Alzheimer's disease and Parkinson's disease. Anosmia appears to be common in dementia with Lewy bodies but not in pure Alzheimer's disease.Objective: To determine whether anosmia improves discrimination between the Lewy body variant (LBV) of Alzheimer's disease and "pure" Alzheimer's disease.Methods: 106 cases of necropsy confirmed pure Alzheimer's disease (n = 89) or LBV (n = 17) were reviewed. All had received butanol odour threshold testing. Anosmia was defined as a score < or = 1.0 on a 0-9 point scale. Logistic regression analysis was used to model potential predictors (for example, parkinsonism, smoking, hallucinations) of neuropathological diagnosis and anosmia.Results: LBV cases had an increased prevalence of anosmia (65%) compared with Alzheimer's disease (23%; odds ratio (OR) = 6.3, p = 0.00045), or normal elderly people (6.7%). Within the dementia cases, the negative predictive value (92%) and specificity (78%) of anosmia were both good; sensitivity for detecting LBV was 65%, but the positive predictive value (PPV) was only 35%. Logistic regression models showed anosmia (OR = 5.4, p = 0.005) and visual hallucinations (OR = 7.3, p = 0.007) were strong independent predictors of Lewy body pathology. When anosmia was added as a core feature to consensus diagnostic criteria for probable Lewy body dementia, five additional cases of LBV were detected (29% increased sensitivity), but with four additional false positives (1% increased discrimination, 4% decreased specificity, 33% decreased PPV).Conclusions: Anosmia is very common in LBV. Adding anosmia as a core feature improved sensitivity for detecting LBV, but did not improve discrimination between Alzheimer's disease and LBV owing to a concomitant increase in false positives.


Related Articles

  • Diagnosis of Alzheimer's disease patients with rapid cognitive decline in clinical practice: Interest of the Deco questionnaire. CARCAILLON, L.; BERRUT, G.; SELLAL, F.; DARTIGUES, J. F.; GILLETTE, S.; PERE, J. J.; BOURDEIX, I. // Journal of Nutrition, Health & Aging;May2011, Vol. 15 Issue 5, p361 

    Background: Patients with Alzheimer's disease (AD) who deteriorate rapidly are likely to have a poorer prognosis. There is a clear need for a clinical assessment fool to defect, such a decline in newly diagnosed patients. Objective: To identify die predictive factors of rapid cognitive decline...

  • New tests to detect early Alzheimer disease.  // Clinical Advisor;Feb2014, Vol. 17 Issue 2, p36 

    The article discusses the use of the Self-Administered Gerocognitive Examination (SAGE) and brain neuroimaging and neuropsychological measures as the useful additions to the arsenal of testing Alzheimer disease.

  • Study Finds Method to Predict Alzheimer's Within 2 Years of Screening.  // Journal of Gerontological Nursing;Feb2014, Vol. 40 Issue 2, p5 

    The article discusses research done on a method for predicting Alzheimer's disease within two years of screening. It references the study "A Method to Predict Alzheimer's Disease Within Two Years of Screening" published in the December 2, 2013 issue of the "Journal of Alzheimer's Disease."...

  • COMPUTERIZED NEUROPSYCHOLOGICAL ASSESSMENTS. Woo, Ellen // Primary Psychiatry;Oct2008 Expert Review Supplement, Vol. 15 Issue Suppl. 6, p14 

    The article examines the application of computerized assessment in the diagnosis of mild cognitive impairment and Alzheimer's disease (AD). It investigates the role of the neuropsychologist in the diagnosis of cognition with the availability of computerized assessments. Identified are the...

  • 尿液 AD7c⁃NTP 表达变化对痴呆诊断价值的探讨. 王艳; 李攀; 陈 嫄; 张惠红; 胡静仪; 陈佳庚; 周玉颖 // Chinese Journal of Contemporary Neurology & Neurosurgery;Aug2015, Vol. 15 Issue 8, p649 

    Objective To investigate the value of Alzheimer ⁃ associated neuronal thread protein (AD7c ⁃ NTP) level in urine for diagnosing dementia. Methods Mini ⁃ Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) were applied to evaluate cognitive function of all...

  • Dementia AND DSM-5: Changes, Cost, and Confusion. Siberski, James // For the Record (Great Valley Publishing Company, Inc.);1/14/2013, Vol. 25 Issue 1, p22 

    The article discusses the how the release of Diagnostic and Statistical Manual of Mental Disorders - 5 (DSM–5) would affect dementia care. It states that DSM-5 includes dementia under “Neurocognitive Disorders” therefore physicians will need to learn the differences between...

  • Ilımlı Kognitif Bozukluk ve Alzheimer Hastalarında MRG ile Hipokampus lm. Öncel, Çağatay; Özdemir, Bülent; Erdoğan, Çağdaş; Kıroğlu, Yılmaz; Şahiner, Türker // Turkish Journal of Neurology / Turk Noroloji Dergisi;ara2011, Vol. 17 Issue 4, p181 

    Objective: In this study, we aimed to compare the hippocampal volumes of patients diagnosed as Alzheimer's disease (AD) and mild cognitive impairment (MCI) and of healthy objects. We also tried to demonstrate whether there was a possible correlation between the cognitive tests and the...

  • Low sensitivity in clinical diagnoses of dementia with Lewy bodies. Nelson, Peter T.; Jicha, Gregory A.; Kryscio, Richard J.; Abner, Erin L.; Schmitt, Frederick A.; Cooper, Gregory; Xu, Li O.; Smith, Charles D.; Markesbery, William R. // Journal of Neurology;Mar2010, Vol. 257 Issue 3, p359 

    The success of future neurodegenerative disease (ND) therapies depends partly on accurate antemortem diagnoses. Relatively few prior studies have been performed on large, multicenter-derived datasets to test the accuracy of final clinical ND diagnoses in relation to definitive neuropathological...

  • On visual hallucinations and cortical networks: a trans-diagnostic review. Carter, Rowena; ffytche, Dominic // Journal of Neurology;Jul2015, Vol. 262 Issue 7, p1780 

    Our current clinical approach to visual hallucinations is largely derived from work carried out by Georges de Morsier in the 1930s. Now, almost a century after his influential papers, we have the research tools to further explore the ideas he put forward. In this review, we address de Morsier's...

  • Brief Memory and Executive Test: evaluation of a new screening test for cognitive impairment due to small vessel disease. Brookes, Rebecca L.; Hannesdottir, Kristin; Lawrence, Robert; Morris, Robin G.; Markus, Hugh S. // Age & Ageing;Mar2012, Vol. 41 Issue 2, p212 

    Background: cerebral small vessel disease (SVD) is the most common cause of vascular cognitive impairment (VCI). Despite this, there is a paucity of rapid simple screening tools to identify cognitive impairment in SVD and differentiate it from other common dementia types.Objective: to validate a...


Read the Article


Sign out of this library

Other Topics