Table 2.
Cerebral PiB retention level of subjects.
| NC (N = 27) | LLOD (N = 29) | LLODwoMCI (N = 15) | LLODMCI (N = 14) | |
|---|---|---|---|---|
| REGIONAL PiB RETENTION | ||||
| Frontal region | 1.20 ± 0.15 | 1.31 ± 0.34 | 1.21 ± 0.18 | 1.42 ± 0.44*a |
| Lateral parietal region | 1.08 ± 0.15 | 1.20 ± 0.32 | 1.14 ± 0.26 | 1.27 ± 0.38*a |
| PC-PRC region | 1.23 ± 0.18 | 1.36 ± 0.36 | 1.28 ± 0.29 | 1.45 ± 0.42*a |
| Lateral temporal region | 1.15 ± 0.11 | 1.26 ± 0.30 | 1.21 ± 0.17 | 1.33 ± 0.39b |
| BG | 1.32 ± 0.14 | 1.38 ± 0.24 | 1.35 ± 0.15 | 1.43 ± 0.31 |
| GLOBAL PiB RETENTION | ||||
| Mean cortical PiB retention | 1.18 ± 0.14 | 1.29 ± 0.32 | 1.21 ± 0.19 | 1.38 ± 0.41*a |
| PiB-positivity (%) | 3 (11.1) | 8 (27.6) | 2 (13.3) | 6 (42.9)*c |
Data are presented as mean ± SD or number (%). Regional and global PiB retention levels are shown as a standardized uptake value ratio (SUVR). For comparison of continuous variables, analysis of covariance test was used with age, gender, and educational level as covariates and chi-square test or Fisher's exact test was used for the comparison of categorical variable.
Significant difference compared to NC (p < 0.05).
LLODMCI subjects showed significantly higher PiB SUVR in frontal (p = 0.040), lateral parietal (p = 0.027), PC-PRC (p = 0.031) and mean cortical (p = 0.036) regions compared to NC after controlling the effect of age, gender, and educational level.
LLODMCI subjects had higher PiB SUVR in the lateral temporal region at marginal significance after controlling the effect of age, gender, and educational level (p = 0.051).
PiB-positivity rate was significantly higher in LLODMCI subjects compared to NC (p = 0.042, Fisher's exact test).
PiB, Pittsburgh Compound B; NC, Normal Controls; LLOD, Late-life Onset Depression; MCI, Mild Cognitive Impairment; LLODwoMCI, LLOD without MCI; LLODMCI, LLOD with MCI; PC-PRC, Posterior Cingulate-Precuneus; BG, Basal Ganglia; SUVR, Standardized Uptake Value Ratio.