THU180 Evaluation Of Factors Affecting Changes In Body Mass Index In Childhood Brain Tumor Survivors

Disclosure: D. Chatila: None. L.A. DiMeglio: None. D. Runco: None. N.G. Haddad: None. Introduction Excessive weight gain in childhood brain tumor (CBT) survivors has been documented. We characterized changes in body mass index (BMI) in CBT survivors and studied possible risk factors for excessive weight gain. Objectives 1) Compare BMI z-score at CBT diagnosis to that at time of last clinical follow up, and 2) Correlate BMI and BMI z-score changes with age at diagnosis; tumor location; treatment including radiation therapy (RT), chemotherapy (CT), or both; presence of endocrinopathies. Methods Following IRB approval, we conducted a retrospective chart review of children with CBTs diagnosed between 2005 and 2017. We excluded children with craniopharyngiomas due to their known high risk of obesity. Results 311 patients (177 female) were identified (median age at diagnosis 6y [range 0-18 y], median follow-up duration 6y [range 1-15 y]. Gliomas were the most common CBT type (69%) then medulloblastomas (18%) and germinomas (6%). 77 (25%) of CBTs were suprasellar. 137 patients received RT, 167 had CT, 110 had both, 7 had only surgery. 95 (30%) of children were ultimately diagnosed with a concomitant endocrinopathy. Baseline BMI and BMI z-scores (18.6 ± 4.8; 0.45 ± 1.52) correlated with mean BMI and BMI z-scores at last follow up [22.5 ± 6.4 (r=0.15, p=0.005); 0.67 ± 1.26, (r=0.11, p=0.048)]. BMI z-scores increased significantly over time. Age at diagnosis was not correlated with change in BMI or BMI z-scores. There were no differences in BMI z-scores at last follow-up or change in BMI z-scores between patients who had suprasellar tumors vs those with other tumor locations (BMI z-scores 0.94 ± 1.53 vs 0.60 ± 1.17, p=0.06; change in BMI z-score 0.36 ± 1.95 vs 0.18 ± 1.84, p=0.47). However, patients with a suprasellar tumor location had a lower mean age at diagnosis (5.6 ± 4.2 years vs 7.2 ± 4.2 years p=0.01). There were no differences in BMI z-scores at last follow-up or change in BMI z-score by type of treatment (CT, RT, or surgery alone) nor were there differences in BMI z-scores at last follow-up or change in BMI z-score between patients who did and did not have endocrinopathies (BMI z-score 0.61 ± 1.29 vs 0.70 ± 1.25, p=0.57; change in BMI z-score 0.03 ± 1.95 vs -0.33 ± 1.817, p=0.11) although children with endocrinopathies were older at CBT diagnosis (8.1 ± 4.9 years vs 6.3 ± 4.5 years, p=0.002) and had a longer duration of follow up than patients without endocrinopathies (7.5 ± 3.4 vs 5.7± 3.0 years, p< 0.001). Conclusions In CBT survivors, BMI z-scores increased over time however this change did not correlate with age at diagnosis of CBT, tumor location, type of intervention received, or presence of endocrinopathies. Future studies are needed to evaluate additional risk factors underlying increases in BMI. Presentation: Thursday, June 15, 2023