Premium
P1‐154: Differences in regional cerebral glucose metabolism between PiB‐positive and ‐negative amnestic mild cognitive impairment: Results from J‐ADNI
Author(s) -
Ishii Kazunari,
Takahashi Ryuichi,
Senda Michio,
Ito Kengo,
Ishii Kenji,
Kato Takashi,
Sugishita Morihiro,
Iwatsubo Takeshi
Publication year - 2012
Publication title -
alzheimer's and dementia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.713
H-Index - 118
eISSN - 1552-5279
pISSN - 1552-5260
DOI - 10.1016/j.jalz.2012.05.432
Subject(s) - posterior cingulate , precuneus , basal forebrain , pittsburgh compound b , medicine , psychology , gyrus , cognitive impairment , alzheimer's disease , neuroimaging , cardiology , pathology , neuroscience , disease , cognition , central nervous system
pal neurofibrillary tangles can be atypical, with cases showing minimal involvement of the hippocampus (Hippocampal Sparing, or HpSp AD), and others showing neurofibrillary tangles restricted to the medial temporal lobe (Limbic predominant or LP AD). We aimed to determine the neuroanatomical correlates of these two pathologically-defined atypical variants of AD (HpSp and LP AD) and compare them to typical AD. Methods: We identified 150 cases that were demented during life, had AD pathological features at autopsy (Braak stage III, intermediatehigh probability AD) and an MRI. The earliest available MRI was utilized in all cases. Cases were assigned to one of three groups (typical AD, HpSp AD, or LPAD) based on the ratio of neurofibrillary tangle counts in association cortices to hippocampus, without reference to neuronal loss. Voxel-based morphometry was used to assess patterns of grey matter loss in each pathological group compared to a cohort of 24 clinically and pathologically normal controls (Braak stage 0-II, low probability AD). Results: Of the 150 cases, 16 (11%) were HpSp AD, 28 (19%) were LP AD, and 106 (70%) were typical AD. All three groups showed grey matter loss in lateral temporoparietal cortex, precuneus and frontal cortex compared to controls (Figure). However, only typical AD and LP AD showed medial temporal loss (Figure). On direct comparison, both LP and typical AD showed greater hippocampal loss than HpSp AD, although LP AD also showed greater hippocampal loss than typical AD. Conversely, HpSp AD showed greater loss in right posterior temporal and parietal lobe than both LP and typical AD. The majority of typical AD (93%) and LP AD (96%) subjects, although only 56% of the HpSp AD subjects, presented with an amnestic syndrome. Conclusions: Approximately one third of AD cases are associated with atypical neurofibrillary tangle distribution and patterns of atrophy. These cases represent an important and under-recognized potential confounder in clinical studies of AD.