TABLE 1.
Down syndrome and sibling control participant demographics by age, sex, cognitive status, and Aβ status. Hypometabolism on FDG defined as having FDG SUVR lower than the mean SUVR from the Aβ– group by 1.5 standard deviations
| Sibling controls | All participants | Aβ– | Striatal Aβ+ | Global Aβ+ | |
|---|---|---|---|---|---|
| N | 14 | 90 | 65 | 25 | 16 |
| Age (mean [SD]) years | 46.6 (13.4) | 38.0 (8.3) | 35.1 (5.81) | 48.3 (5.87) | 50.4 (4.24) |
| Sex (M/F) | 1/13 | 45/45 | 33/32 | 12/13 | 9/7 |
| MCI‐DS/AD consensus | 0 | 10 | 2 | 8 | 7 |
| Hypometabolism on FDG | 0 | 12 | 2 | 10 | 10 |
| Episodic memory Z‐score | NA | 0.00 (1.89) | 0.57 (1.45) | –1.38 (2.11) | –2.15 (2.20) |
| Overall cognition Z‐score | NA | 0.00 (5.32) | 1.57 (4.25) | –4.09 (5.67) | –5.46 (6.01) |
Abbreviations: Aβ, amyloid beta; FDG, fluorodeoxyglucose; MCI‐DS, mild cognitive impairment‐Down syndrome; SD, standard deviation; SUVR, standardized uptake value ratio.