OUTC-03. IMPACT OF TREATMENT EXPOSURES AND SOCIOECONOMIC STATUS ON NEUROCOGNITIVE PERFORMANCE IN CHILDREN WITH BRAIN TUMORS

PURPOSE: To investigate the impact of treatment exposures and socioeconomic status on neurocognitive performance in children with brain tumors. METHODS: Eligible patients included those diagnosed with a brain tumor at <22 years of age with ≥ 1 neurocognitive assessment. Neurocognitive impairment was defined as performance 1.5 standard deviations below the normative mean using age standardized measures of intellectual function. Neurocognitive outcomes included Wechsler indices of full-scale intelligent quotient (IQ), working memory (WM), and processing speed (PS). Neurocognitive decline was defined as a negative slope. Logistic regression identified variables associated with neurocognitive impairment. Longitudinal data was analyzed using linear mixed models. RESULTS: Eligible patients (n=152) had a mean neurocognitive follow-up of 50.2 months and median age at diagnosis of 9.6 years. PS was most frequently impaired in patients (37.5%) followed by IQ (20.6%) and WM (16.5%). Patients with public insurance had eight-fold increased odds of impaired IQ compared to those with private insurance (Odds Ratio [OR]: 7.59, p<0.001). Patients treated with CSI had eight-fold increased odds of impaired IQ (OR: 7.86, p=0.003) and almost six-fold increased odds of impaired WM (OR: 5.66, p=0.028) compared to those treated without RT. After accounting for age, change in IQ was associated with chemotherapy use (slope: -0.45 points/year with chemotherapy vs. 0.71 points/year without chemotherapy, p=0.012). Patients treated with both chemotherapy and RT demonstrated the greatest decline whereas those treated without either demonstrated no decline in any of the neurocognitive measures. CONCLUSION: After treatment for pediatric brain tumors, public insurance, an indicator of low socioeconomic status, was associated with impairment in IQ with a large effect size similar to that of CSI. Chemotherapy was associated with decline in IQ with a small effect size. Combined chemotherapy and RT had additive effects on neurocognitive decline in IQ, WM, and PS.