Dataset Information

Longitudinal changes in amyloid positron emission tomography and volumetric magnetic resonance imaging in the nondemented Down syndrome population.

ABSTRACT: Down syndrome (DS) arises from a triplication of chromosome 21, causing overproduction of the amyloid precursor protein and predisposes individuals to early Alzheimer's disease (AD).Fifty-two nondemented adults with DS underwent two cycles of carbon 11-labeled Pittsburgh compound B ([11C]PiB) and T1 weighted magnetic resonance imaging (MRI) scans 3.0 ± 0.6 years apart. Standard uptake value ratio (SUVR) images (50-70 minutes; cerebellar gray matter [GM]) and GM volumes were analyzed in standardized space (Montreal Neurological Institute space).85% of PiB(-) subjects remained PiB(-), whereas 15% converted to PiB(+), predominantly in the striatum. None reverted from PiB(+) to PiB(-). Increases in SUVR were distributed globally, but there were no decreases in GM volume. The PiB positivity groups differed in the percent rate of change in SUVR [PiB(-): 0.5%/year, PiB converters: 4.9%/year, and PiB(+): 3.7%/year], but not in GM volume.Despite the characteristic striatum-first pattern, the global rate of amyloid accumulation differs by pre-existing amyloid burden and precedes atrophy or dementia in the DS population, similar to general AD progression.

SUBMITTER: Lao PJ

PROVIDER: S-EPMC5454131 | biostudies-other | 2017

REPOSITORIES: biostudies-other

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Longitudinal changes in amyloid positron emission tomography and volumetric magnetic resonance imaging in the nondemented Down syndrome population.

Lao Patrick J PJ Handen Ben L BL Betthauser Tobey J TJ Mihaila Iulia I Hartley Sigan L SL Cohen Annie D AD Tudorascu Dana L DL Bulova Peter D PD Lopresti Brian J BJ Tumuluru Rameshwari V RV Murali Dhanabalan D Mathis Chester A CA Barnhart Todd E TE Stone Charles K CK Price Julie C JC Devenny Darlynne A DA Mailick Marsha R MR Klunk William E WE Johnson Sterling C SC Christian Bradley T BT

Alzheimer's & dementia (Amsterdam, Netherlands) 20170523

<h4>Introduction</h4>Down syndrome (DS) arises from a triplication of chromosome 21, causing overproduction of the amyloid precursor protein and predisposes individuals to early Alzheimer's disease (AD).<h4>Methods</h4>Fifty-two nondemented adults with DS underwent two cycles of carbon 11-labeled Pittsburgh compound B ([<sup>11</sup>C]PiB) and T1 weighted magnetic resonance imaging (MRI) scans 3.0 ± 0.6 years apart. Standard uptake value ratio (SUVR) images (50-70 minutes; cerebellar gray matter ...[more]

PMID: 28603769

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Dataset Information

Longitudinal changes in amyloid positron emission tomography and volumetric magnetic resonance imaging in the nondemented Down syndrome population.

Publications

Longitudinal changes in amyloid positron emission tomography and volumetric magnetic resonance imaging in the nondemented Down syndrome population.

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