Beta‐amyloid plaque accumulation comparison in down syndrome and non‐down syndrome cohorts

Background Down syndrome (DS) is characterized by earlier beta-amyloid (Aβ) plaque accumulation and an increased prevalence of Alzheimer’s disease (AD) due to trisomy 21 triplication the amyloid precursor protein (APP) gene. While age AD onset in DS, pathology progression non-DS populations follows similar trends DS cohort. This study compares rate Aβ between measured with [C-11]PiB at same site using scanning procedures. Methods Individuals least one Aβ+ scan (Global SUVR>1.40), Aβ- from our University Wisconsin were selected for this study. 12 out 58 participants Neurodegeneration Aging (NiAD) 14 246 subjects PREDICT fit criteria. All images collected on ECAT HR+ scanner 50-70 minutes injection (i.d. = 15mCi). Reconstructed PET aligned summed before being normalized into MNI-152 space converted SUVR image cerebellar grey matter as a reference region. We determined change global per year, defined average regions anterior cingulate, frontal cortex, parietal precuneus, temporal striatum, focused period when became Aβ+. Results Plotting (Fig 1) there no overlap two groups. The year becoming group was 0.058±0.026 compared 0.059±0.028 sample. groups have notably mean values, although organized box plots 2), interquartile range 0.044 tighter 0.019 non-DS. Conclusions pattern distributions. we might expect higher population additional APP gene, findings do not support hypothesis. However, considerable variability observed requiring further investigation towards understanding process.