Tau-proteins as gender-specific state markers in amnestic mild cognitive impairment.

BACKGROUND/AIMS: Our purpose was to assess whether cerebrospinal fluid (CSF) markers of Alzheimer's disease (AD) reflect trait or state of disease in patients with AD and amnestic mild cognitive impairment (aMCI). METHODS: Analysis of CSF levels of A-ß-(1, 42), total tau and phospho-tau-181 (t-tau and p-tau-181), cognitive scaling with the cognitive part of the Alzheimer's Disease Assessment Scale and detailed neuropsychological testing including the California Verbal Learning Test (CVLT) and the Visual Reproduction Test from the Wechsler Memory Scale (WMS). RESULTS: We assessed healthy elderly controls, patients with aMCI (Petersen criteria; n = 62; age 67.9 ± 7.6 years; MMSE score = 28.0 ± 1.6; mean ± standard deviation) and patients with AD (DSM-IV and NINCDS-ADRDA criteria; n = 106; age = 71.8 ± 7.5 years; MMSE score ≥20, 23.7 ± 2.4) from an outpatient memory clinic. In the aMCI subjects, but not in the controls or patients with AD, the CVLT and the WMS scores correlated with the levels of t-tau and p-tau-181. More specifically, the CSF levels of p-tau-181 and t-tau correlated with the CVLT score in females and WMS score in males. CONCLUSIONS: Neurochemical markers of AD are gender-specific state markers in aMCI. This forms the basis for future preventive studies aiming at delaying manifest AD.