title: Combining select neuropsychological assessment with blood-based biomarkers to detect mild Alzheimer's disease: a molecular neuropsychology approach.
abstract: BACKGROUND
  Current work has sought to establish a rapid and cost effective means of screening for Alzheimer's disease (AD) with the most recent findings showing utility of integrating blood-based biomarkers with cognitive measures.
  
  
  OBJECTIVE
  The current project sought to create a combined biomarker-cognitive profile to detect mild AD.
  
  
  METHODS
  Data was analyzed from 266 participants (129 AD cases [Early AD n = 93; Very Early AD n = 36]; 137 controls) enrolled in the Texas Alzheimer's Research and Care Consortium (TARCC). Non-fasting serum samples were collected from each participant and assayed via a multi-plex biomarker assay platform using electrochemiluminescence. Logistic Regression was utilized to detect early AD using two serum biomarkers (TNFα and IL7), demographic information (age), and one neuropsychological measure (Clock 4-point) as predictor variable. Disease severity was determined via Clinical Dementia Rating (CDR) scale global scores.
  
  
  RESULTS
  In the total sample (all levels of CDR scores), the combination of biomarkers, cognitive test score, and demographics yielded the obtained sensitivity (SN) of 0.94, specificity (SP) of 0.90, and an overall accuracy of 0.92. When examining early AD cases (i.e.m CDR = 0.5-1), the biomarker-cognitive profile yielded SN of 0.94, SP of 0.85, and an overall accuracy of 0.91. When restricted to very early AD cases (i.e., CDR = 0.5), the biomarker-cognitive profile yielded SN of 0.97 and SP of 0.72, with an overall accuracy of 0.91.
  
  
  CONCLUSIONS
  The combination of demographics, two biomarkers, and one cognitive test created a biomarker-cognitive profile that was highly accurate in detecting the presence of AD, even in the very early stages.
authors.affiliation: Department of Psychology, University of North Texas, Denton, TX, USA.
authors.forename: Melissa
authors.initials: M
authors.lastname: Edwards
authors.affiliation: Department of Psychology, South Texas Veterans Health Care System, San Antonio, TX, USA.
authors.forename: Valerie Hobson
authors.initials: VH
authors.lastname: Balldin
authors.affiliation: Department of Psychiatry, University of North Texas Health Science Center, Fort Worth, TX, USA Institute for Aging & Alzheimer's Disease Research, University of North Texas Health Science Center, Fort Worth, TX, USA.
authors.forename: James
authors.initials: J
authors.lastname: Hall
authors.affiliation: Institute for Aging & Alzheimer's Disease Research, University of North Texas Health Science Center, Fort Worth, TX, USA Department of Internal Medicine, University of North Texas Health Science Center, Fort Worth, TX, USA.
authors.forename: Sid
authors.initials: S
authors.lastname: O'Bryant
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood / Q000150:complications / Q000175:diagnosis; D015415:Biomarkers / Q000097:blood*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers
keywords: Alzheimer's disease; biomarkers; molecular; neuropsychology