Association between FDG uptake, CSF biomarkers and cognitive performance in patients with probable Alzheimer's disease.
OBJECTIVE
Brain imaging of FDG uptake and cerebrospinal fluid (CSF) concentration of amyloid-beta 1-42 (Abeta(1-42)) or tau proteins are promising biomarkers in the diagnosis of Alzheimer's disease (AD). There is still uncertainty regarding any association between decreased FDG uptake and alterations in CSF markers.


METHODS
The relationship between FDG uptake, CSF Abeta(1-42) and total tau (T-tau), as well as the Mini-Mental State Examination (MMSE) score was investigated in 34 subjects with probable AD using step-wise linear regression. FDG uptake was scaled to the pons.


RESULTS
Scaled FDG uptake was significantly reduced in the probable AD subjects compared to 17 controls bilaterally in the precuneus/posterior cingulate area, angular gyrus/inferior parietal cortex, inferior temporal/midtemporal cortex, midfrontal cortex, and left caudate. Voxel-based single-subject analysis of the probable AD subjects at p < 0.001 (uncorrected) revealed a total volume of significant hypometabolism ranging from 0 to 452 ml (median 70 ml). The total hypometabolic volume was negatively correlated with the MMSE score, but it was not correlated with the CSF measures. VOI-based step-wise linear regression revealed that scaled FDG uptake in the precuneus/posterior cingulate was negatively correlated with CSF Abeta(1-42). Scaled FDG uptake in the caudate was positively correlated with CSF T-tau.


CONCLUSIONS
The extent and local severity of the reduction in FDG uptake in probable AD subjects are associated with cognitive impairment. In addition, there appears to be a relationship between local FDG uptake and CSF biomarkers which differs between different brain regions.
Arlt
Sönke
S
Department of Psychiatry and Psychotherapy, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Brassen
Stefanie
S
Jahn
Holger
H
Wilke
Florian
F
Eichenlaub
Martin
M
Apostolova
Ivayla
I
Wenzel
Fabian
F
Thiele
Frank
F
Young
Stewart
S
Buchert
Ralph
R
D000368:Aged; D000544:Alzheimer Disease / Q000134:cerebrospinal fluid / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000523:psychology*; D001057:Apolipoproteins E / Q000235:genetics; D015415:Biomarkers / Q000134:cerebrospinal fluid; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism; D003071:Cognition; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism*; D005500:Follow-Up Studies; D005838:Genotype; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011336:Probability; D012189:Retrospective Studies; D012984:Software
D001057:Apolipoproteins E; D015415:Biomarkers; D019788:Fluorodeoxyglucose F18