title: CSF biomarkers predict a more malignant outcome in Alzheimer disease.
abstract: OBJECTIVE
  To investigate if patterns of CSF biomarkers (T-tau, P-tau, and Abeta42) can predict cognitive progression, outcome of cholinesterase inhibitor (ChEI) treatment, and mortality in Alzheimer disease (AD).
  
  
  METHODS
  We included outpatients with AD (n = 151) from a prospective treatment study with ChEI. At baseline, patients underwent cognitive assessments and lumbar puncture. The patients were assessed longitudinally. The 5-year survival rate was evaluated. CSF-Abeta42, T-tau, and P-tau were analyzed at baseline. K-means cluster analysis including the 3 CSF biomarkers was carried out.
  
  
  RESULTS
  Cluster 1 contained 87 patients with low levels of Abeta42 and relatively low levels of T-tau and P-tau. Cluster 2 contained 52 patients with low levels of Abeta42 and intermediate levels of T-tau and P-tau. Cluster 3 contained 12 patients with low levels of Abeta42 and very high levels of CSF T-tau and P-tau. There were no differences between the clusters regarding age, gender, years of education, baseline instrumental activities of daily living, or APOE genotype. Even though there was no difference between cluster 3 and the other clusters in disease duration or global rating, the patients in cluster 3 performed worse on cognitive tests already at baseline. Patients in cluster 3 exhibited a very poor outcome of ChEI treatment. Finally, cognition deteriorated faster over time and the mortality rate was substantially increased in cluster 3.
  
  
  CONCLUSIONS
  A subgroup of patients with Alzheimer disease with extreme levels of CSF biomarkers exhibits worse clinical outcomes over time, including faster progression of cognitive deficits, no response to ChEI treatment, and a higher mortality.
authors.affiliation: Malmö University Hospital, SE-205 02 Malmö, Sweden. asa.k.wallin@skane.se
authors.forename: A K
authors.initials: AK
authors.lastname: Wallin
authors.forename: K
authors.initials: K
authors.lastname: Blennow
authors.forename: H
authors.initials: H
authors.lastname: Zetterberg
authors.forename: E
authors.initials: E
authors.lastname: Londos
authors.forename: L
authors.initials: L
authors.lastname: Minthon
authors.forename: O
authors.initials: O
authors.lastname: Hansson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis* / Q000188:drug therapy / Q000401:mortality; D016229:Amyloid beta-Peptides / Q000134:cerebrospinal fluid*; D015415:Biomarkers / Q000134:cerebrospinal fluid; D002800:Cholinesterase Inhibitors / Q000627:therapeutic use; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009483:Neuropsychological Tests; D017063:Outcome Assessment, Health Care; D010446:Peptide Fragments / Q000134:cerebrospinal fluid*; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome; D016875:tau Proteins / Q000134:cerebrospinal fluid*
chemical_list: D016229:Amyloid beta-Peptides; D015415:Biomarkers; D002800:Cholinesterase Inhibitors; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42); D016875:tau Proteins