Longitudinal outcomes of amyloid positive versus negative amnestic mild cognitive impairments: a three-year longitudinal study.

ABSTRACT: We aimed to compare the longitudinal outcome of amnestic mild cognitive impairment (aMCI) patients with significant Pittsburgh Compound B uptake [PiB(+) aMCI] and those without [PiB(-) aMCI]. Cerebral ?-amyloid was measured in 47 patients with aMCI using PiB-positron emission tomography (PET) (31 PiB(+) aMCI and 16 PiB(-) aMCI). Clinical (N?=?47) and neuropsychological follow-up (N?=?37), and follow-up with brain magnetic resonance imaging (N?=?38) and PiB-PET (N?=?30) were performed for three years. PiB(+) aMCI had a higher risk of progression to dementia (hazard ratio?=?3.74, 95% CI?=?1.21-11.58) and faster rate of cortical thinning in the bilateral precuneus and right medial and lateral temporal cortices compared to PiB(-) aMCI. Among six PiB(-) aMCI patients who had regional PiB uptake ratio >1.5 in the posterior cingulate cortex (PCC), three (50.0%) progressed to dementia, and two of them had global PiB uptake ratio >1.5 at the follow-up PiB-PET. Our findings suggest that amyloid imaging is important for predicting the prognosis of aMCI patients, and that it is necessary to pay more attention to PiB(-) aMCI with increased regional PiB uptake in the PCC.

SUBMITTER: Ye BS 

PROVIDER: S-EPMC5883059 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature