Table 4.
Regression analyses for all KL-VS genotype groups from meta-analysis of Cohorts 1 and 2
| Beta estimate (STD error) | P-value | |
|---|---|---|
| I. Outcome: rDLPFC volume | ||
| Meta-analysis: Cohorts 1 and 2 | ||
| Total intracranial volume | 1.39 × 10−6 (2.51 × 10−7) | 5.62 × 10−8 |
| Age | −0.05 (0.01) | 7.29 × 10−13 |
| Sex (F) | −0.07 (0.10) | 0.52 |
| Education | −0.02 (0.02) | 0.31 |
| Center | −0.58 (0.12) | 1.61 × 10−06 |
| APOE ε4 carrier | −0.09 (0.11) | 0.40 |
| Genotype, KL-VS | 0.24 (0.09) | 0.01 |
| II. Outcome: Composite exec. Z-score | ||
| Meta-analysis: Cohorts 1 and 2 | ||
| Age | −0.03 (0.01) | 5.25 × 10−5 |
| Sex (F) | −0.13 (0.10) | 0.20 |
| Education | 0.07 (0.02) | 1.42 × 10−4 |
| Center | −0.44 (0.12) | 4.40 × 10−4 |
| APOE ε4 carrier | 0.03 (0.12) | 0.83 |
| Genotype, KL-VS | 0.21 (0.10) | 0.03 |
| III. Outcome: Composite exec. Z-score with rDLPFC volume | ||
| Meta-analysis: Cohorts 1 and 2 | ||
| rDLPFC volume | 0.11 (0.01) | 0.03 |
| Total intracranial volume | −5.22 × 10−7 (2.75 × 10−7) | 0.06 |
| Age | −0.02 (0.01) | 2.76 × 10−3 |
| Sex (F) | −0.18 (0.11) | 0.10 |
| Education | 0.07 (0.02) | 7.54 × 10−5 |
| Center | −0.36 (0.13) | 4.83 × 10−3 |
| APOE ε4 carrier | 0.03 (0.12) | 0.80 |
| Genotype, KL-VS | 0.18 (0.10) | 0.07 |
KL-VS genotype is associated with greater rDLPFC volume and enhanced executive function after accounting for several variables. The estimate and accompanying error reflect the effect (beta) of each independent variable as a predictor of rDLPFC volume or composite executive Z-score after accounting for all other variables in the model. For meta-analysis, the linear statistical model included as independent variables: age, sex, education, APOE ε4 carrier status, total intracranial volume (TIV, in I and III only), KL-VS genotype (homozygotes scored as 0, noncarriers scored as 1, and heterozygotes scored as 2) and test center. All tests were two-tailed. rDLPFC, right dorsolateral prefrontal cortex.