Cerebrospinal fluid beta-amyloid 42 is reduced before the onset of sporadic dementia: a population-based study in 85-year-olds.

Abstract

Deposition of beta-amyloid (Abeta) is an early pathogenic event in Alzheimer's disease (AD). We measured Abeta42 and Abeta40 in cerebrospinal fluid (CSF) in a population-based sample of 85-year-olds, 27 demented and 35 non-demented. During the following 3 years, 7 of the 35 non-demented individuals had developed dementia, while 28 remained non-demented. Reduced CSF levels of both Abeta42 (p = 0.001) and Abeta40 (p = 0.0001) were found in patients with manifest AD and vascular dementia at the age of 85. Non-demented individuals who developed dementia during follow-up had lower levels of CSF- Abeta42 (p = 0.003), but not CSF-Abeta40 (p = 0.96), than those who remained non-demented. The odds ratio for development of dementia was 8.2 (p = 0.027) for individuals in the lower 50th percentile of CSF-Abeta42, while none of those in the highest 33rd percentile of CSF-Abeta42 developed dementia during follow-up. There were no significant differences between carriers and non-carriers of the apolipoprotein E epsilon4 allele regarding CSF-Abeta42 or CSF-Abeta40. Our study suggests that low CSF-Abeta42 is found also in an unselected population-based sample of old demented patients and provides the first evidence of a disturbance in the metabolism of Abeta, specifically involving Abeta42, before the onset of clinical symptoms in AD.

• Authors: I Skoog, P Davidsson, O Aevarsson, H Vanderstichele, E Vanmechelen, K Blennow
• Journal: Dementia and geriatric cognitive disorders (Dement Geriatr Cogn Disord) Vol. 15 Issue 3 Pg. 169-76 ( 2003) ISSN: 1420-8008 [Print] Switzerland
• PMID: 12584433 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright 2003 S. Karger AG, Basel

Chemical References

• Amyloid beta-Peptides
• Apolipoproteins E
• Peptide Fragments
• Protein Isoforms
• amyloid beta-protein (1-40)
• amyloid beta-protein (1-42)

Topics

• Aged
• Aged, 80 and over
• Alzheimer Disease (cerebrospinal fluid)
• Amyloid beta-Peptides (cerebrospinal fluid)
• Apolipoproteins E (genetics)
• Brain (pathology)
• Dementia (cerebrospinal fluid)
• Female
• Follow-Up Studies
• Humans
• Male
• Peptide Fragments (cerebrospinal fluid)
• Population Surveillance
• Protein Isoforms (genetics)
• Risk Factors
• Sampling Studies