Open AccessEpicentral Disruption of Structural Connectivity in Alzheimer's Disease
Author(s) -
Mallio Carlo Augusto,
Schmidt Ruben,
Reus Marcel A.,
Vernieri Fabrizio,
Quintiliani Livia,
Curcio Giuseppe,
Beomonte Zobel Bruno,
Quattrocchi Carlo Cosimo,
den Heuvel Martijn P.
Publication year - 2015
Publication title -
cns neuroscience and therapeutics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.403
H-Index - 69
eISSN - 1755-5949
pISSN - 1755-5930
DOI - 10.1111/cns.12397
Subject(s) - entorhinal cortex , hippocampus , hippocampal formation , neuroscience , cognitive impairment , ring (chemistry) , disease , functional connectivity , cognition , medicine , psychology , chemistry , organic chemistry
Summary Aims Neurodegenerative changes observed in Alzheimer's disease ( AD ) have been suggested to begin at the entorhinal cortex and hippocampus and then to propagate in a stereotypical fashion. Using diffusion‐weighted imaging, we test whether disruption of structural connectivity in AD is centered on these “epicenters of disease”. Methods Fifteen healthy controls, 14 amnestic mild cognitive impairment ( aMCI ), 13 mild, and 15 moderate patients with AD were enrolled. The percentages of affected connections directly linking to the epicenter (named first ring) and to nodes with topological distance 2 from the epicenter (named second ring) were calculated. Results For the group of aMCI patients, just 5.3% of the first ring (n.s.) and 2.9% of the second ring (n.s.) connections were affected. However, for mild AD there was disruption involving 20% of the first ring ( P < 0.0001) and 10.3% of the second ring ( P < 0.0001) connections. In the moderate AD group, a stronger effect was observed, with 38.0% of the first ring ( P < 0.0001) connections and 17.9% of the second ring ( P < 0.0001) connections affected. Conclusion Our results favor an epicentral disruption of structural connectivity in aMCI and AD around entorhinal and hippocampal regions, consistent with the transneuronal spread hypothesis.