Clinical and biological predictors of Alzheimer's disease in patients with amnestic mild cognitive impairment

Objective To identify predictors of the progression from pre-dementia stages of cognitive impairment in Alzheimer s disease is relevant to clinical management and to substantiate the decision of prescribing antidementia drugs Method Longitudinal study of a cohort of elderly adults with amnestic mild cognitive impairment and healthy controls carried out to estimate the risk and characterize predictors of the progression to Alzheimer s disease Results Patients with amnestic mild cognitive impairment had a higher risk to develop Alzheimer s disease during follow up (odds ratio = 4 5 CI95% [1 3 13 6] p = 0 010) At baseline older age lower scores on memory tests and presence of the APOE*4 allele predicted the progression from amnestic mild cognitive impairment to Alzheimer s disease In a sub sample of amnestic mild cognitive impairment patients those who progressed to Alzheimer s disease had lower cerebrospinal fluid concentrations of amyloid beta peptide (A beta(42) p = 0 020) and higher concentrations of total TAU (p = 0 030) and phosphorylated TAU (p = 0 010) as compared to non-converters Discussion This is the first Brazilian study to report cerebrospinal fluid biomarkers in the prediction of the conversion from MCI to Alzheimer s disease Our data are in accordance with those reported in other settings The measurement of cerebrospinal fluid total TAU phospho TAU and A beta(42) may help identify patients with mild cognitive impairment at higher risk for developing Alzheimer s disease