VBM anticipates the rate of progression of Alzheimer disease

Abstract

Objective: To determine whether regional atrophy or neuropsychological factors can predict the rate of decline in patients with mild Alzheimer disease (AD). Background: Despite important implications for planning the care and treatment strategy, few prognostic factors of severe AD progression are known. Methods: Twenty-three patients with mild AD were followed up every 6 months over the course of 3 years. At baseline, patients with AD and 18 controls underwent a neuropsychological battery and a brain MRI. At the end of the 3 years, patients with AD were dichotomized into slow decliners (SLD) or fast decliners (FD) groups on the basis of their decline in Mini-Mental State Examination score over time. We compared baseline cognitive performance and imaging data using voxel-based morphometry (VBM). Results: SLD and FD groups did not differ in age, gender, level of education, mean estimated duration of illness, and standard neuropsychological data at inclusion, except for the Attentional Battery of the Cambridge Neuropsychological Tests Automated Battery (speed processing in shifting condition). VBM comparison between SLD and FD groups demonstrated more gray matter tissue loss in the FD group in the medial occipitoparietal areas, especially in the precuneus, the lingual gyrus, the cuneus, and the surrounding cortex of the parieto-occipital sulcus bilaterally. Conclusion: Voxel-based morphometry analysis demonstrated that patients who will have a faster decline at 3 years already had a more extensive cortical atrophy than SLD patients, especially in the medial occipitoparietal areas, which was not yet detected by clinical and neuropsychological assessment.