Gray matter atrophy patterns of mild cognitive impairment subtypes

Zhang, Haobo; Sachdev, Perminder S.; Wen, Wei; Kochan, Nicole A.; Crawford, John D.; Brodaty, Henry; Slavin, Melissa J.; Reppermund, Simone; Draper, Brian; Zhu, Wanlin; Kang, Kristan; Trollor, Julian N.

doi:10.1016/j.jns.2011.12.011

« Previous Next »Journal of the Neurological Sciences
Volume 315, Issue 1 , Pages 26-32, 15 April 2012

Gray matter atrophy patterns of mild cognitive impairment subtypes

Haobo Zhang
- Brain and Ageing Research Program, School of Psychiatry, University of New South Wales, Sydney, Australia
Perminder S. Sachdev
- Brain and Ageing Research Program, School of Psychiatry, University of New South Wales, Sydney, Australia
- Neuropsychiatric Institute, Prince of Wales Hospital, Randwick, NSW, Australia
Wei Wen
- Brain and Ageing Research Program, School of Psychiatry, University of New South Wales, Sydney, Australia
- Academic Department for Old Age Psychiatry, Prince of Wales Hospital, Randwick, NSW, Australia
Nicole A. Kochan
- Brain and Ageing Research Program, School of Psychiatry, University of New South Wales, Sydney, Australia
- Academic Department for Old Age Psychiatry, Prince of Wales Hospital, Randwick, NSW, Australia
John D. Crawford
- Brain and Ageing Research Program, School of Psychiatry, University of New South Wales, Sydney, Australia
Henry Brodaty
- Dementia Collaborative Research Centre, School of Psychiatry, University of New South Wales, Sydney, Australia
- Department of Developmental Disability Neuropsychiatry, School of Psychiatry, University of New South Wales, Sydney, Australia
Melissa J. Slavin
- Department of Developmental Disability Neuropsychiatry, School of Psychiatry, University of New South Wales, Sydney, Australia
Simone Reppermund
- Brain and Ageing Research Program, School of Psychiatry, University of New South Wales, Sydney, Australia
Brian Draper
- Brain and Ageing Research Program, School of Psychiatry, University of New South Wales, Sydney, Australia
- Dementia Collaborative Research Centre, School of Psychiatry, University of New South Wales, Sydney, Australia
Wanlin Zhu
- Brain and Ageing Research Program, School of Psychiatry, University of New South Wales, Sydney, Australia
Kristan Kang
- Brain and Ageing Research Program, School of Psychiatry, University of New South Wales, Sydney, Australia
Julian N. Trollor
- Brain and Ageing Research Program, School of Psychiatry, University of New South Wales, Sydney, Australia
- Academic Department for Old Age Psychiatry, Prince of Wales Hospital, Randwick, NSW, Australia
- Corresponding author at: Department of Developmental Disability Neuropsychiatry, Botany St Houses, University of New South Wales, NSW 2052, Australia. Tel.: +61 2 9931 9160; fax: +61 2 9931 9154.

Received 23 June 2011; received in revised form 30 November 2011; accepted 21 December 2011. published online 27 January 2012.

Abstract

Mild cognitive impairment (MCI) is a heterogeneous neurocognitive disorder that can be classified into various subtypes. The present study aims to examine the gray matter (GM) atrophy patterns of MCI subtypes in comparison with a cognitively healthy group. Participants, including 135 MCI subjects and 120 cognitively healthy controls, were drawn from the Sydney Memory and Ageing Study. The MCI subjects were first categorized into amnestic (aMCI) and non-amnestic (naMCI) subtypes, which were then divided into single-domain (aMCI-SD and naMCI-SD) and multiple-domain subtypes (aMCI-MD and naMCI-MD). Furthermore, naMCI-SD was divided into three subgroups (language, processing speed, and executive function) according to individual cognitive impairment. Voxel-wise GM volumes were then compared between MCI subtypes and controls. The aMCI group had significantly lower GM volumes in the bilateral hippocampi and temporal cortices than the controls. This was mainly due to GM reduction of aMCI-MD but not aMCI-SD, as the latter did not show any significant GM reduction. GM reduction of naMCI and its two subdivisions was shown in widespread brain regions compared to controls. GM volumes of the multiple-domain subtypes (aMCI-MD and naMCI-MD) were lower than their single-domain counterparts (aMCI-SD and naMCI-SD) in the frontal and temporal lobes, respectively. Moreover, the language subgroup of naMCI-SD showed GM reduction in the frontal and temporal lobes compared to controls. MCI subtypes displayed specific patterns of GM atrophy that appear to be related to their various clinical presentations, which implies that underlying mechanisms of MCI subtypes are different.

Keywords: Mild cognitive impairment, Subtype, Gray matter, Magnetic resonance imaging, Voxel-based morphometry