Cerebrospinal fluid markers in dementia with lewy bodies compared with Alzheimer disease.
BACKGROUND
Most patients with dementia with Lewy bodies (DLB) exhibit diffuse plaque-only pathology with rare neocortical neurofibrillary tangles (NFTs), as opposed to the widespread cortical neurofibrillary-tau involvement in Alzheimer disease (AD). Another pathological difference is the astrocytic and microglial inflammatory responses, including release of interleukins (ILs), around the neuritic plaques and NFTs in AD brains that are absent or much lower in DLB. We analyzed cerebrospinal fluid (CSF) markers that reflect the pathological differences between AD and DLB.


OBJECTIVE
To determine CSF concentrations of tau, beta-amyloid, IL-1beta, and IL-6 as potential diagnostic clues to distinguish between AD and DLB.


METHODS
We measured total tau, beta-amyloid1-42, IL-1beta, and IL-6 levels in CSF samples of 33 patients with probable AD without parkinsonism, 25 patients with all the core features of DLB, and 46 age-matched controls.


RESULTS
Patients with AD had significantly higher levels of tau protein than patients with DLB and controls (P<.001). The most efficient cutoff value provided 76% specificity to distinguish AD and DLB cases. Patients with AD and DLB had lower, but not significantly so, beta-amyloid levels than controls. The combination of tau and beta-amyloid levels provided the best sensitivity (84%) and specificity (79%) to differentiate AD vs controls but was worse than tau values alone in discriminating between AD and DLB. Beta-amyloid levels had the best correlation with disease progression in both AD and DLB (P =.01). There were no significant differences in IL-1beta levels among patients with AD, patients with DLB, and controls. Patients with AD and DLB showed slightly, but not significantly, higher IL-6 levels than controls.


CONCLUSIONS
The tau levels in CSF may contribute to the clinical distinction between AD and DLB. Beta-amyloid CSF levels are similar in both dementia disorders and reflect disease progression better than tau levels. Interleukin CSF concentrations do not distinguish between AD and DLB.
Gómez-Tortosa
Estrella
E
Department of Neurology, Fundación Jiménez Díaz, the Brain Bank for Neurological Research, Complutense University, Madrid, Spain. egomez@fjd.es
Gonzalo
Isabel
I
Fanjul
Samira
S
Sainz
Maria José
MJ
Cantarero
Susana
S
Cemillán
Carlos
C
Yébenes
Justo García
JG
del Ser
Teodoro
T
D000368:Aged; D000544:Alzheimer Disease / Q000134:cerebrospinal fluid* / Q000276:immunology / Q000473:pathology; D016229:Amyloid beta-Peptides / Q000134:cerebrospinal fluid; D001253:Astrocytes / Q000276:immunology / Q000378:metabolism; D003072:Cognition Disorders / Q000175:diagnosis; D003463:Cues; D005260:Female; D006801:Humans; D007375:Interleukin-1 / Q000134:cerebrospinal fluid / Q000276:immunology; D015850:Interleukin-6 / Q000134:cerebrospinal fluid / Q000276:immunology; D020961:Lewy Body Disease / Q000134:cerebrospinal fluid* / Q000276:immunology / Q000473:pathology; D008297:Male; D017628:Microglia / Q000276:immunology / Q000378:metabolism; D016874:Neurofibrillary Tangles / Q000473:pathology; D009483:Neuropsychological Tests; D016875:tau Proteins / Q000134:cerebrospinal fluid
D016229:Amyloid beta-Peptides; D007375:Interleukin-1; D015850:Interleukin-6; D016875:tau Proteins