Elevation of the Plasma Aß40/Aß42 Ratio as a Diagnostic Marker of Sporadic Early-Onset Alzheimer's Disease.
J Alzheimers Dis
; 48(4): 1043-50, 2015.
Article
em En
| MEDLINE
| ID: mdl-26444752
ABSTRACT
BACKGROUND:
Although plasma amyloid-ß (Aß) levels have been evaluated as a possible diagnostic marker of Alzheimer's disease (AD), the findings are inconsistent.OBJECTIVE:
The present study aimed to validate plasma levels of Aß40, Aß42, and the Aß40/Aß42 ratio as biomarkers of AD in subjects with early-onset AD (EOAD) without familial AD genetic mutations.METHODS:
Patients with sporadic EOAD (sEOAD) were prospectively recruited by nine neurology clinics. Plasma levels of Aß40 and Aß42 were measured using a sandwich enzyme-linked immunosorbent assay (ELISA) in 100 sEOAD (50-69 year-old) and 46 age-matched normal control subjects (50-72 year-old). Cerebrospinal fluid (CSF) was obtained from 32 sEOAD subjects and 25 controls. The integrity of the blood-brain barrier was assessed using the CSF/plasma albumin ratio.RESULTS:
The plasma levels of Aß42 were significantly lower, while the Aß40/Aß42 ratio was significantly higher in sEOAD patients than in controls. The levels of Aß40, Aß42, and the Aß40/Aß42 ratio did not differ in relation to the APOEÉ4 allele. The CSF/plasma albumin ratio was comparable between the two groups, and the plasma parameters of Aß proteins were not significantly associated. A multivariate analysis revealed that an increased Aß40/Aß42 ratio is valuable for the discrimination of sEOAD from controls (ß=0.344, p=0.000). The area under the ROC curve for the Aß40/Aß42 ratio was 0.76, and a cut-off ratio of 5.87 was suggested to have 70% sensitivity and 68% specificity.CONCLUSION:
The plasma Aß40/Aß42 ratio had moderate validity for the discrimination of sEOAD patients from age-matched controls.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fragmentos de Peptídeos
/
Peptídeos beta-Amiloides
/
Doença de Alzheimer
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Limite:
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
J Alzheimers Dis
Assunto da revista:
GERIATRIA
/
NEUROLOGIA
Ano de publicação:
2015
Tipo de documento:
Article