The pediatric growth curve as a cancer research tool

Comparison of birth weight corrected for gestational age and birth weight alone in prediction of development of childhood leukemia and central nervous system tumors

INTRODUCTION

High birth weight (HBW) is an established risk factor for childhood acute lymphoblastic leukemia (ALL). The purpose of this study was to evaluate if birth weight (BW) corrected-for-gestational age is a better predictor than BW alone for occurrence of ALL and other malignancies in children.

MATERIALS AND METHODS

Birth certificate data of 2,254 children with cancer who were younger than 5 years old at diagnosis and registered at Texas Cancer Registry during 1995-2003 were compared to 11,734 age-matched controls. Multivariable logistic regression was used to compare models with BW corrected-for-gestational age and BW alone.

RESULTS

Compared to children who were appropriate for gestational age (AGA), children who were large for gestational age (LGA) at birth had a 1.66 times (95% CI 1.32-2.10) higher odds of ALL. Similarly, children with a BW > or =4,000 g had a 1.5 times (95% CI 1.18-1.89) higher odds for ALL, compared to children who weighed >2,500 and <4,000 g at birth. Using model diagnostics, the model containing BW corrected-for-gestational age was a better predictor than the model with BW alone [Akaike's Information Criterion (AIC) 4,646 vs. 4,658, respectively]. Odds ratios (OR) were similar for LGA children who were <4,000 g and LGA children who were > or =4,000 g (OR = 1.5, 95% CI 0.97-2.5 and OR = 1.67, 95% CI 1.29-2.16, respectively). BW was not an independent risk factor for acute myeloid leukemia or brain tumors.

CONCLUSION

BW corrected-for-gestational age is a better predictor than BW alone of risk for ALL. Future studies using BW variable should incorporate gestational age in their analyses.