Florbetapir PET, FDG PET, and MRI in Down syndrome individuals with and without Alzheimer's dementia

Alzheimers Dement. 2015 Aug;11(8):994-1004. doi: 10.1016/j.jalz.2015.01.006. Epub 2015 Apr 4.


Introduction: Down syndrome (DS) is associated with amyloid b (Ab) deposition.

Methods: We characterized imaging measurements of regional fibrillar Ab burden, cerebral metabolic rate for glucose (rCMRgl), gray matter volumes (rGMVs), and age associations in 5 DS with dementia (DS/AD1), 12 DS without dementia (DS/AD2), and 9 normal controls (NCs).

Results: There were significant group differences in mean standard uptake value ratios (SUVRs) for florbetapir with DS/AD1 having the highest, followed by DS/AD2, followed by NC. For [18F]-fluorodeoxyglucose positron emission tomography, posterior cingulate rCMRgl in DS/AD1 was significantly reduced compared with DS/AD2 and NC. For volumetric magnetic resonance imaging (vMRI), hippocampal volumes were significantly reduced for the DS/AD1 compared with DS/AD2 and NC. Age-related SUVR increases and rCMRgl reductions were greater in DS participants than in NCs.

Discussion: DS is associated with fibrillar Ab, rCMRgl, and rGMV alterations in the dementia stage and before the presence of clinical decline. This study provides a foundation for the studies needed to inform treatment and prevention in DS.

Keywords: Alzheimer's disease; Dementia; Down syndrome; FDG-PET; Florbetapir; Imaging; PET.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Alzheimer Disease / complications
  • Aniline Compounds / metabolism*
  • Brain / diagnostic imaging*
  • Brain / pathology*
  • Down Syndrome / complications
  • Down Syndrome / pathology*
  • Emergency Services, Psychiatric
  • Ethylene Glycols / metabolism*
  • Female
  • Fluorodeoxyglucose F18 / metabolism*
  • Humans
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Neuropsychological Tests
  • Positron-Emission Tomography*


  • Aniline Compounds
  • Ethylene Glycols
  • Fluorodeoxyglucose F18
  • florbetapir