TABLE 1.
Descriptive statistics for participant demographics and plasma biomarkers.
| M (SD)/ n (%) | ||||
|---|---|---|---|---|
| Total sample (n = 260) | Cognitively stable (n = 219) | MCI‐DS (n = 41) | χ2 or t value | |
| Chronological age | 43.74 (9.51) | 42.14 (9.06) | 52.27 (7.10) | −7.99 ** |
| Sex, n (%) male | 144 (55.4%) | 115 (52.5%) | 29 (70.7%) | 4.64 * |
| Race | ||||
| White | 249 (95.7%) | 211 (96.3%) | 38 (92.7%) | 6.48 * |
| Black | 3 (1.2%) | 1 (0.5%) | 2 (4.9%) | |
| Asian | 3 (1.2%) | 2 (0.9%) | 1 (2.4%) | |
| Unreported | 5 (1.9%) | 5 (2.3%) | – | |
| Ethnicity | ||||
| Non‐Hispanic | 248 (95.4%) | 207 (94.5%) | 41 (100%) | 2.36 |
| Hispanic | 12 (4.6%) | 12 (5.5%) | – | |
| Down syndrome type | ||||
| Trisomy 21 | 223 (85.8%) | 189 (86.3%) | 34 (82.9%) | 2.45 |
| Mosaicism | 9 (3.5%) | 6 (2.7) | 3 (7.3%) | |
| Translocation | 18 (6.9%) | 16 (7.3%) | 2 (4.9%) | |
| Unreported | 10 (3.8%) | 8 (3.7%) | 2 (4.9%) | |
| Lifetime ID level | ||||
| Mild | 141 (54.2%) | 123 (56.2%) | 18 (43.9%) | 4.22 |
| Moderate | 97 (37.3%) | 76 (34.7%) | 21 (51.2%) | |
| Severe | 22 (8.5%) | 20 (9.1%) | 2 (4.9%) | |
| Cognitive/functional measures | ||||
| mCRT | 29.02 (9.17) | 31.17 (7.01) | 17.51 (10.75) | 7.84 ** |
| VMI | 15.79 (3.58) | 16.19 (3.43) | 13.68 (3.69) | 4.24 ** |
| Block Design (with Haxby) | 24.24 (11.14) | 25.49 (10.30) | 17.59 (13.12) | 3.65 ** |
| Vineland‐3 ABC | 47.47 (18.54) | 49.48 (18.42) | 36.73 (15.39) | 4.17 ** |
| Plasma biomarkers | ||||
| Plasma Aβ42/40 | 0.034 (0.004) | 0.034 (0.004) | 0.033 (0.005) | 1.45 |
| Plasma total tau (pg/mL) | 2.29 (0.77) | 2.21 (0.70) | 2.73 (0.97) | −3.96 ** |
| Plasma NfL (pg/mL) | 16.92 (10.72) | 15.31 (9.73) | 25.92 (11.62) | −6.09 ** |
Abbreviations: ABC, Adaptive Behavior Composite; Aβ, amyloid beta; ID, intellectual disability; mCRT, modified Cued Recall Test; MCI‐DS, mild cognitive impairment–Down syndrome; NfL, neurofilament light chain; SD, standard deviation; VMI, visual motor integration.
*
P < 0.05.
**
P < 0.01.