Mild Cognitive Impairment: Same Identity for Different Entities

作者：Serra Laura; Giulietti Giovanni; Cercignani Mara; Spano Barbara; Torso Mario; Castelli Diana; Perri Roberta; Fadda Lucia; Marra Camillo; Caltagirone Carlo; Bozzali Marco^*

来源：Journal of Alzheimer's Disease, 2013, 33(4): 1157-1165.

DOI：10.3233/JAD-2012-121663

• Alzheimer%26apos
• s disease
• amnestic mild cognitive impairment
• magnetic resonance imaging
• non-amnestic mild cognitive impairment
• voxel-based morphometry

This study investigates whether different patterns of grey matter (GM) loss may account for the different neuropsychological profiles observed in patients with amnestic (a-) and non-amnestic (na-) mild cognitive impairment (MCI), and may predict patients%26apos; clinical evolution. Fifty-five consecutive individuals complaining of cognitive dysreferred to specialist dementia clinics) were screened and included in the study if they met the diagnostic criteria for MCI on a neurodegenerative basis. After an extensive neuropsychological assessment, patients were classified as suffering from a-MCI or na-MCI. Twenty-eight healthy individuals were also recruited and served as controls. All participants underwent magnetic resonance imaging at 3T, including conventional images and volumetric scans. Volumetric data were processed using voxel-based morphometry to assess between-group differences in regional GM volumes and correlations with neuropsychological performances. When compared to controls, a-MCI patients showed prominent GM volume reductions in the medial temporal lobes, while those with na-MCI showed reduced GM volumes in the orbito-frontal cortex and basal ganglia. In a-MCI patients, significant associations were found between verbal long-term memory performance and GM volumes in the hippocampus. Conversely, in na-MCI patients, associations were found between scores at tests exploring executive functions and GM volumes in the orbito-frontal cortex. At one-year follow-up, conversions were recorded exclusively toward Alzheimer%26apos;s disease (AD) in the a-MCI group, and toward non-AD dementia in the na-MCI group. This study confirms that MCI is a heterogeneous clinical identity including different neurodegenerative entities; specific patterns of regional GM loss appear to account for specific neuropsychological features and are likely to predict patients%26apos; clinical evolution.

• 出版日期2013