Table 1:
Sample characteristics stratified by remote mTBI group (LOC or PTA required)
| Overall | Remote mTBI with LOC or Dazed/PTA | Sig. (p) | Effect Sizec | |||
|---|---|---|---|---|---|---|
| 0 | 1 | 2+ | ||||
| N | 134 | 86 | 31 | 17 | ||
| Age, M (SD) y | 74.1 (6.8) | 74.1 (6.4) | 73.5 (8.1) | 74.6 (6.2) | .88 | η2<0.01 |
| Sex, N (%) female | 80 (59.7) | 55 (64) | 14 (45) | 11 (65) | .17 | V=0.16 |
| Education, M (SD) y | 17.4 (2.1) | 17.4 (2.1) | 17.4 (2.1) | 17.6 (2.0) | .93 | η2<0.01 |
| Race, N (%) white | 115 (85.8) | 75 (87) | 27 (87) | 13 (76) | .32 | V=0.13 |
| Missing, N (%) | 6 (4.5) | 4 (5) | 0 (0) | 2 (12) | - | - |
| APOE, N (%) e4 carrier | 26 (19.4) | 12 (14) | 7 (23) | 7 (41) | .03 | V=0.23 |
| mTBI Characteristics | d | |||||
| Time since first mTBI, M (SD) y | 45.8 (21.5) | - | 41.5 (22.6) | 53.4 (17.7) | .07 | 0.57 |
| Time since last mTBI, M (SD) y | 37.1 (23.2) | - | 41.5 (22.6) | 29.5 (22.9) | .09 | 0.53 |
| Age at first mTBI, M (SD) y | 27.9 (22.2) | - | 31.8 (24.2) | 21.2 (16.9) | .11 | 0.48 |
| Age at last mTBI, M (SD) y | 36.6 (23.9) | - | 31.8 (24.2) | 45.2 (21.4) | .06 | 0.58 |
| ≥1 mTBI w/ LOC<30min, N (%) | 29 (21.6) | 0 (0) | 15 (48) | 14 (82) | - | - |
| PTA<24hrs only, N (%) | 19 (14.2) | 0 (0) | 16 (52) | 3 (18) | - | - |
| Aβ-PET | ||||||
| Positive, N (%) | 26 (19.4) | 16 (19) | 8 (26) | 2 (17) | .52 | V=0.11 |
| Centiloid, Mdn. (IQR) | 5.2 (−3.7, 16.9) | 4.6 (−4.3, 17.4) 7 | .5 (−4.3, 17.6) | 6.6 (0.5, 14.1) | .94a | η2<0.01 |
| Cognition (Z-scores), M (SD) | η2 | |||||
| Memory | 0.11 (0.80) | 0.08 (0.76) | 0.18 (0.79) | 0.13 (1.1) | .57b | 0.01 |
| Executive Function | 0.86 (058) | 0.91 (0.58) | 0.85 (0.52) | 0.64 (0.64) | .21b | 0.03 |
| Missing, Memory/Exec. N (%) | 15 (11.2)/7 (5.2) | 9 (10)/3 (3) | 5 (16)/3 (10) | 1 (6)/1 (6) | - | - |
a
ANCOVA with Centiloid as the dependent variable and age, sex, and APOE e4 carrier status covariates
b
ANCOVA with cognitive z-scores as the dependent variable and age, sex, education, and APOE e4 covariates
c
Effect size estimates presented either as eta squared (η2) or Cohen’s d for continuous variables and Cramer’s V for categorical variables
Abbrev: Aβ-PET – amyloid positron emission tomography, APOE – apolipoprotein E, M (SD) – mean (standard deviation) Mdn (IQR) – median (interquartile range), mTBI – mild traumatic brain injury, y – years