TABLE 6.
Associations between grey and white matter CVR and Tau with clinical and biological variables on multivariable analysis. Only associations with p ≤ 0.2 were included in the models.
| CVR Z-score | Tau Z-score | |||||
|---|---|---|---|---|---|---|
| Unstandardized | p-value | VIF | Unstandardized | p-value | VIF | |
| Grey matter | ||||||
| Age | −0.03 | 0.07 | 1.01 | - | - | - |
| SCD genotype (SS/Sβ0 vs SC/Sβ+) | −0.25 | 0.14 | 2.4 | - | - | - |
| Systolic blood pressure | - | - | - | −0.05 | 0.11 | 1.00 |
| Hematocrit a | 11.75 | 0.01 | 2.4 | - | - | - |
| White blood cells | - | - | - | −0.20 | 0.03 | 1.00 |
| Model statistics | R2 = 0.60, Adjusted R2 = 0.48 | R2 = 0.43, Adjusted R2 = 0.33 | ||||
| White matter | ||||||
| Age | −0.01 | 0.62 | 1.18 | - | - | - |
| Systolic blood pressure | - | - | - | −0.05 | 0.07 | 1.00 |
| White blood cells | 0.08 | 0.25 | 1.07 | −0.22 | 0.007 | 1.00 |
| Hydroxyurea | 0.66 | 0.15 | 1.12 | - | - | |
| Model statistics | R2 = 0.38, Adjusted R2 = 0.20 | R2 = 0.55, Adjusted R2 = 0.47 | ||||
a
Hemaglobin and hematocrit were highly colinear (VIF = 20–27).
Abbreviations: CVR, cerebrovascular reactivity; SCD, sickle cell disease; VIF, variation inflation factor.