title: Peri-gestational risk factors for pediatric brain tumors in Neurofibromatosis Type 1.
abstract: Individuals with Neurofibromatosis Type 1 (NF1) are strongly predisposed to developing pediatric brain tumors (PBTs), especially optic pathway gliomas (OPGs). Although developmental factors have been implicated in the origins of PBTs in both human and animal studies, associations between early-life factors and PBTs have not been evaluated in individuals with NF1. Our objective was to evaluate associations between peri-gestational characteristics and PBTs in this population.
  
  
  
  We conducted a cross-sectional study, ascertaining questionnaire and medical record data for 606 individuals<18years old who enrolled in the NF1 Patient Registry Initiative (NPRI) from 6/9/2011-6/29/2015. One hundred eighty-four individuals had reported PBT diagnoses, including 65 who were identified with OPG diagnoses. Cox proportional hazards regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between PBT and OPG diagnoses and peri-gestational characteristics (prematurity, birth weight, parental age, plurality, family history of NF1, assisted reproductive technology, maternal vitamin supplementation, and parental smoking).
  
  
  
  We observed no significant associations between any of the assessed characteristics and PBTs overall or OPGs with the exception of birth weight. After controlling for potential confounding variables, we observed a significant positive association between birth weight quartile and OPGs with a HR of 3.32 (95% CI 1.39-7.94) for the fourth (≥3915.5g) compared to the first (≤3020g) quartile (p for trend=0.001).
  
  
  
  Consistent with results for PBTs in the general population, these results suggest that higher birth weights increase OPG risk in individuals with NF1.
authors.affiliation: Brown School, Washington University, St. Louis, MO 63130, United States. Electronic address: kijohnson@wustl.edu.
authors.forename: Kimberly J
authors.initials: KJ
authors.lastname: Johnson
authors.affiliation: Brown School, Washington University, St. Louis, MO 63130, United States.
authors.forename: Nancy L
authors.initials: NL
authors.lastname: Zoellner
authors.affiliation: Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, United States.
authors.forename: David H
authors.initials: DH
authors.lastname: Gutmann
mesh_terms: D000293:Adolescent; D001724:Birth Weight / Q000235:genetics*; D001932:Brain Neoplasms / Q000209:etiology*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009456:Neurofibromatosis 1 / Q000150:complications*; D020339:Optic Nerve Glioma / Q000209:etiology*; D012307:Risk Factors
keywords: Birth weight; Brain neoplasms; Glioma; Neurofibromatosis 1