title: Biomarkers Differentiating Dementia with Lewy Bodies from Other Dementias: A Meta-Analysis.
abstract: BACKGROUND
  Several nuclear imaging and cerebrospinal fluid (CSF) biomarkers are under investigation, aimed at facilitating the differential diagnosis of dementias.
  
  
  OBJECTIVE
  To quantitatively synthesize data on test performance in differentiating dementia with Lewy bodies (DLB) from other dementias.
  
  
  METHODS
  We searched PubMed (January 2000- March 2015) for English-language publications that assessed a selected set of five imaging and three CSF biomarkers for this purpose. We meta-analyzed measures of agreement between biomarker results and clinical diagnosis.
  
  
  RESULTS
  Forty-five publications were eligible. The majority of evidence was based on studies that enrolled representative disease populations. For differentiating between DLB and Alzheimer's disease (AD) or other dementias, metaiodobenzylguanidine scintigraphy and dopamine transporter (DAT) single photon emission computed tomography (SPECT) showed, respectively, excellent (summary kappa = 0.85; 95% confidence interval [95% CI], 0.74-0.96) and good (summary kappa = 0.71; 95% CI, 0.43-0.99) agreement. Metaiodobenzylguanidine scintigraphy appeared superior to fluorodeoxyglucose- positron emission tomography (summary kappa = 0.53; 95% CI, 0.36-0.69) and cerebral blood flow SPECT (summary kappa = 0.40; 95% CI, 0.33-0.47). For differentiating DLB from AD, CSF t-tau levels (summary kappa = 0.68; 95% CI, 0.55-0.82) performed comparably to metaiodobenzylguanidine scintigraphy and DAT SPECT. Sparse direct comparative evidence failed to corroborate these indirect comparisons.
  
  
  CONCLUSIONS
  Metaiodobenzylguanidine scintigraphy and DAT SPECT are highly concordant with clinical diagnosis in differentiating DLB from other dementias. However, given the limitations in the study design, the applicability of these results to real-world differential diagnosis remains unclear. Prospective studies targeting patients with atypical presentations that adopt gold standard tests would reliably estimate the true test performance of these promising biomarkers.
authors.affiliation: Section of General Internal Medicine, Department of Emergency and General Internal Medicine, Fujita Health University School of Medicine, Toyoake, Aichi, Japan.
authors.forename: Aki
authors.initials: A
authors.lastname: Mishima
authors.affiliation: Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Nihashi
authors.affiliation: Department of Radiology, Toyota Memorial Hospital, Toyota, Aichi, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Ando
authors.affiliation: Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Kawai
authors.affiliation: Department of Radiology, Clinical and Experimental Neuroimaging, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kato
authors.affiliation: Department of Radiology, Clinical and Experimental Neuroimaging, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan.
authors.forename: Kengo
authors.initials: K
authors.lastname: Ito
authors.affiliation: Section of General Internal Medicine, Department of Emergency and General Internal Medicine, Fujita Health University School of Medicine, Toyoake, Aichi, Japan.|Center for Clinical Evidence Synthesis, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA.
authors.forename: Teruhiko
authors.initials: T
authors.lastname: Terasawa
mesh_terms: D015415:Biomarkers / Q000378:metabolism*; D003704:Dementia / Q000378:metabolism* / Q000473:pathology*; D003937:Diagnosis, Differential; D006801:Humans; D016631:Lewy Bodies / Q000000981:diagnostic imaging / Q000473:pathology; D039781:PubMed / Q000706:statistics & numerical data; D011877:Radionuclide Imaging; D012189:Retrospective Studies
chemical_list: D015415:Biomarkers
keywords: Alzheimer’s disease; dementia; dementia with Lewy bodies; diagnosis; meta-analysis