Table 2.
Linear regression models for the association between CBF and cognitive functioning.
| Group | Cognitive domain | Model | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | ||
| Age and sex | Model 1 + education | Model 1 + ethnicity | Model 1 + hyper-tension | Model 1 + diabetes | Model 1 + smoking | Model 1 + WMH volume | Model 1 + hippo-campal volume | Full model (all variables) | ||
| All | Global cognition | 0.18** | 0.18*** | 0.07 | 0.15** | 0.16** | 0.15** | 0.17** | 0.16** | 0.06 |
| (n = 452) | Memory | 0.15*** | 0.14** | 0.11* | 0.14** | 0.14** | 0.12* | 0.15* | 0.14** | 0.06 |
| Executive func/attention | 0.17*** | 0.16** | 0.09* | 0.15* | 0.15** | 0.18*** | 0.18*** | 0.16** | 0.11* | |
| Language | 0.14** | 0.13* | 0.03 | 0.12* | 0.13** | 0.10 | 0.13** | 0.13** | −0.02 | |
| European | Global cognition | 0.12 | 0.11 | n.a. | 0.11 | 0.11 | 0.13 | 0.12 | 0.11 | 0.14 |
| (n = 215) | Memory | 0.13* | 0.12* | n.a. | 0.13* | 0.13* | 0.13* | 0.14* | 0.13* | 0.14* |
| Executive fun /attention | 0.18** | 0.18** | n.a. | 0.18** | 0.18** | 0.19** | 0.17* | 0.18** | 0.18** | |
| Language | 0.01 | 0.00 | n.a. | 0.01 | 0.01 | 0.01 | −0.01 | 0.00 | −0.02 | |
| South Asian | Global cognition | 0.04 | 0.06 | n.a. | 0.03 | 0.04 | −0.01 | 0.04 | 0.04 | 0.00 |
| (n = 151) | Memory | 0.07 | 0.07 | n.a. | 0.05 | 0.07 | −0.06 | 0.08 | 0.07 | −0.05 |
| Executive func/attention | −0.01 | −0.04 | n.a. | −0.03 | −0.01 | 0.02 | 0.05 | −0.01 | −0.01 | |
| Language | −0.00 | 0.01 | n.a. | −0.01 | −0.00 | −0.04 | −0.02 | 0.01 | −0.07 | |
| African Caribbean | Global cognition | 0.04 | 0.04 | n.a. | 0.01 | 0.01 | 0.04 | −0.06 | 0.05 | −0.11 |
| (n = 87) | Memory | 0.05 | 0.02 | n.a. | 0.04 | 0.02 | −0.02 | −0.01 | 0.04 | −0.15 |
| Executive func/attention | 0.04 | −0.01 | n.a. | 0.02 | 0.04 | 0.10 | 0.02 | 0.05 | 0.05 | |
| Language | −0.10 | 0.10 | n.a. | 0.08 | 0.07 | 0.03 | 0.10 | 0.10 | 0.02 | |
Executive func, executive functioning; WMH, white matter hyperintensities; n.a., not applicable.
p < 0.05,
p < 0.01,
p < 0.001.
Results are presented as standardized beta [stß] to allow comparison of effect sizes. We used linear regression analyses with cerebral blood flow (CBF) as independent variable and cognitive domains as dependent variable. Cognition is expressed as (composite) z-score. Model 1: Univariate regression analysis, adjusted for age and sex; Model 2–8: All analyses are adjusted for age and sex + named variable; Model 9: We entered all variables (age, sex, education, ethnicity, vascular risk factors and MRI measures) simultaneously in one model (Enter method). Results were subsequently stratified for ethnicity.