Prediction of conversion from amnestic mild cognitive impairment to Alzheimer's disease using proton magnetic resonance spectroscopy

Abstract

Amnestic mild cognitive impairment (aMCI) has been considered to be a transitional state between healthy aging and very mild Alzheimer's disease (AD). Most patients with aMCI convert to AD over time, but some of them remain stable as aMCI. In this study, 22 patients with aMCI underwent proton magnetic resonance spectroscopy (1H-MRS) of hippocampus and posterior cingulate cortex. Ten patients converted to AD had significantly lower N-acetylaspartate (NAA) concentrations in both hippocampi when compared to 12 patients remained stable to be aMCI. The mean NAA concentration of both hippocampi equal to or lower than 7.6 mmol/l predicted conversion to AD at 1.0 sensitivity and 1.0 specificity and the area under receiver operating curve (ROC) was 1.0. Absolute quantification of 1H-MRS of hippocampus seems to be a useful marker for predicting conversion to AD from patients with aMCI .