title: Comparisons of clinical symptoms in biomarker-confirmed Alzheimer's disease, dementia with Lewy bodies, and frontotemporal dementia patients in a local memory clinic.
abstract: BACKGROUND
  There has been no previous Chinese study that differentiated the clinical symptoms among biomarker-confirmed Alzheimer's disease (AD), dementia with Lewy bodies (DLB) and frontotemporal dementia (FTD). The objective of this study was to compare the cognitive, behavioural, and neuropsychiatric symptoms in biomarker-confirmed AD, DLB, and FTD patients.
  
  
  METHODS
  We recruited 30 patients (14 AD, 7 DLB, 9 FTD) who presented to the memory clinic at Queen Mary Hospital from 1 January 2007 to 31 December 2013. AD was diagnosed according to the National Institution of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association criteria with cerebrospinal fluid biomarkers (tau, phosphorylated tau, and amyloid β-42) fulfilling locally determined cut-off values for AD. DLB was diagnosed based on the McKeith diagnostic criteria. The behavioural variant of FTD was diagnosed based on the revised diagnostic criteria proposed by the International bvFTD Criteria Consortium, and language variant FTD was diagnosed based on the latest published criteria. In addition, patients with DLB and FTD had typical imaging features on single-photon emission computed tomography or (18) fludeoxyglucose-positron emission tomography, either with or without Pittsburgh Compound B imaging, which supported their diagnoses. Data on patient characteristics including demographics, presenting clinical features, Mini-Mental State Examination, clinical dementia ratings, and neuropsychiatry inventory scores were collected.
  
  
  RESULTS
  There were no differences in age, education level, dementia severity, and duration of symptoms before presentation among the three subgroups of patients. All patients had amnesia symptoms, which were not statistically significant. Apraxia was most common in AD. While 83% of the patients were affected by behavioural and neuropsychiatric symptoms of dementia, behavioural disinhibition and decline in executive function were most common in FTD patients. Recurrent hallucinations, fluctuation of consciousness, parkinsonism, and rapid eye movement sleep behaviour disorder were most common in DLB.
  
  
  CONCLUSIONS
  Memory impairment and apathy are not useful discriminative symptoms in diagnosing AD, DLB, and FTD. Apraxia favours AD. Hallucinations, particularly well-formed visual hallucinations, favour DLB. Overall, behavioural and neuropsychiatric symptoms of dementia symptoms are common among the three groups of dementia patients.
authors.affiliation: Divsion of Geriatrics, Department of Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong.
authors.forename: Yat Fung
authors.initials: YF
authors.lastname: Shea
authors.affiliation: Divsion of Geriatrics, Department of Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong.
authors.forename: Joyce
authors.initials: J
authors.lastname: Ha
authors.affiliation: Divsion of Geriatrics, Department of Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong.|The Alzheimer's Disease Research Network, SRT Aging, The University of Hong Kong, Hong Kong.
authors.forename: Leung-Wing
authors.initials: LW
authors.lastname: Chu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000134:cerebrospinal fluid / Q000175:diagnosis*; D016229:Amyloid beta-Peptides / Q000134:cerebrospinal fluid*; D015415:Biomarkers / Q000134:cerebrospinal fluid / Q000378:metabolism; D056344:Executive Function; D005260:Female; D057180:Frontotemporal Dementia / Q000134:cerebrospinal fluid / Q000175:diagnosis*; D006212:Hallucinations / Q000175:diagnosis; D006801:Humans; D020961:Lewy Body Disease / Q000134:cerebrospinal fluid / Q000175:diagnosis*; D008297:Male; D008609:Mental Status Schedule / Q000706:statistics & numerical data; D008875:Middle Aged; D020734:Parkinsonian Disorders / Q000175:diagnosis; D010446:Peptide Fragments / Q000134:cerebrospinal fluid*; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D015899:Tomography, Emission-Computed, Single-Photon; D016875:tau Proteins / Q000134:cerebrospinal fluid*
chemical_list: D016229:Amyloid beta-Peptides; D015415:Biomarkers; D010446:Peptide Fragments; D019275:Radiopharmaceuticals; C075222:amyloid beta-protein (1-42); D016875:tau Proteins
keywords: Alzheimer's disease; Lewy body disease; biomarker; frontotemporal dementia