Cerebrospinal fluid (CSF) biomarkers improve the diagnostic accuracy for Alzheimer's disease (AD), even at the predementia stage of the disease. The ?4-allele of apolipoprotein E (ApoE ?4), female sex, and older age are well-known risk factors for AD. It is unclear how these risk factors affect the CSF biomarkers in patients with AD.The objective of this study was to investigate the associations of ApoE ?4, sex, and age with CSF biomarker levels in a unicenter sample of patients with AD that includes a high proportion of patients with early-onset AD (EOAD).The CSF levels of amyloid-? 1-42 (A?1-42) and total-tau of 117 subjects with mild to moderate AD (55 late-onset AD and 62 EOAD) were assessed. All subjects underwent ApoE genotyping, clinical evaluation, comprehensive neuropsychological assessments, and neuroimaging. Associations between CSF biomarker levels, ApoE ?4 allele frequency, age, and sex were evaluated.In the whole patient sample and in the late-onset AD subgroup ?4 homozygous subjects had significantly lower CSF A?1-42 levels compared with ?4 heterozygous subjects and ?4 noncarriers. This association was not detected in the EOAD group. Age group, sex, and severity of cognitive decline did not have a significant impact on CSF A?1-42 levels. No significant associations were found between ApoE ?4 allele frequency and CSF total-tau levels.ApoE ?4 allele is associated with a reduction of CSF A?1-42 levels. This result is consistent with the findings of several previous studies. In the subgroup of patients with EOAD this association was not replicated. Larger studies are necessary to further investigate associations between ApoE ?4 allele frequency and CSF biomarker levels in patients with EOAD.     «

Cerebrospinal fluid (CSF) biomarkers improve the diagnostic accuracy for Alzheimer's disease (AD), even at the predementia stage of the disease. The ?4-allele of apolipoprotein E (ApoE ?4), female sex, and older age are well-known risk factors for AD. It is unclear how these risk factors affect the CSF biomarkers in patients with AD.The objective of this study was to investigate the associations of ApoE ?4, sex, and age with CSF biomarker levels in a unicenter sample of patients with AD that inc...     »