Table 4.
Multivariable Regression Models Predicting Domains of Neurocognitive Impairment
| Parameters | Intelligence |
Academic |
Attention |
Memory |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| RR | 95% CI | P | OR | 95% CI | P | RR | 95% CI | P | RR | 95% CI | P | |
| CRT, Gy | ||||||||||||
| None | 1.0 | 1.0 | 1.0 | 1.0 | ||||||||
| 18 | 1.46 | 0.46 to 4.60 | .52 | 8.13 | 1.67 to 39.59 | .01 | 1.48 | 0.96 to 2.30 | .08 | 2.05 | 0.86 to 4.86 | .11 |
| 24 | 6.63 | 2.54 to 17.27 | < .001 | 8.56 | 2.08 to 35.26 | .003 | 2.15 | 1.46 to 3.18 | < .001 | 5.04 | 2.33 to 10.94 | < .001 |
| Age at diagnosis (years)* | — | — | — | — | ||||||||
| Age at diagnosis by CRT, Gy | ||||||||||||
| None | —† | —† | — | —† | ||||||||
| 18 | —† | —† | — | —† | ||||||||
| 24 | —† | —† | — | —† | ||||||||
| Time since diagnosis (per 1 year)* | — | — | — | — | ||||||||
| Time since diagnosis by CRT, Gy | ||||||||||||
| None | — | — | — | — | ||||||||
| 18 | — | — | — | — | ||||||||
| 24 | — | — | — | — | ||||||||
| Sex | ||||||||||||
| Male | 1.0 | 1.0 | — | — | ||||||||
| Female | 1.61 | 1.10 to 2.36 | .02 | 3.62 | 1.86 to 7.04 | < .001 | — | — | ||||
| Sex by CRT, Gy | ||||||||||||
| Male | ||||||||||||
| None | — | — | — | — | ||||||||
| 18 | — | — | — | — | ||||||||
| 24 | — | — | — | — | ||||||||
| Female | ||||||||||||
| None | — | — | — | — | ||||||||
| 18 | — | — | — | — | ||||||||
| 24 | — | — | — | — | ||||||||
| IV methotrexate (1 g/m2) | — | — | — | — | ||||||||
| Processing Speed |
Executive Function |
Behavior Rating |
Cognitive Rating |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| RR | 95% CI | P | RR | 95% CI | P | OR | 95% CI | P | OR | 95% CI | P |
| 1.0 | 1.0 | 1.0 | 1.0 | ||||||||
| 1.05 | 0.60 to 1.83 | .86 | 1.62 | 0.22 to 11.77 | .63 | 1.83 | 0.91 to 3.70 | .09 | 2.66 | 0.96 to 7.35 | .06 |
| 1.09 | 0.64 to 1.86 | .75 | 0.46 | 0.07 to 2.90 | .41 | 1.72 | 0.78 to 3.80 | .18 | 0.86 | 0.24 to 3.11 | .82 |
| — | — | — | — | ||||||||
| — | — | — | — | ||||||||
| — | — | — | — | ||||||||
| — | — | — | — | ||||||||
| — | — | 1.05 | 1.01 to 1.09 | .03 | — | ||||||
| — | —† | — | — | ||||||||
| — | —† | — | — | ||||||||
| — | —† | — | — | ||||||||
| — | — | — | — | ||||||||
| — | — | — | — | ||||||||
| 1.0 | — | — | 1.0 | ||||||||
| 1.47 | 0.77 to 2.81 | .24 | — | — | 2.66 | 0.96 to 7.35 | .06 | ||||
| 1.57 | 0.83 to 2.97 | .16 | — | — | 0.86 | 0.24 to 3.11 | .82 | ||||
| 1.0 | — | — | 1.0 | ||||||||
| 1.19 | 0.54 to 2.64 | .67 | — | — | 0.60 | 0.22 to 1.67 | .33 | ||||
| 3.25 | 1.68 to 6.30 | < .001 | — | — | 1.95 | 0.97 to 3.91 | .06 | ||||
| 1.03 | 1.00 to 10.6 | .03 | — | — | |||||||
NOTE. ORs were used instead of RRs for academic, behavioral rating, and cognitive rating outcomes because of lower frequency of severe impairment on these outcomes. (—) Indicates variables that were not retained in the models based on Akaike information criterion.
Abbreviations: CRT, cranial radiation therapy; IV, intravenous; OR, odds ratio; RR, relative risk.
*
Represented as a continuous variable; effect indicates increased risk with each year.
†
Significant risk based on interaction between age at diagnosis or time since diagnosis and cranial radiation dose.