Growth charts for children with cerebral palsy: Weight and stature percentiles by age, gender, and level of disability

Abstract

Growth charts for the general population, whether reference charts from the CDC or standards for healthy children developed by the WHO, are of limited use for children with cerebral palsy (CP), whose weight-for-age and stature-for-age often track below the 5th percentiles on such charts. In this chapter we review previous work on CP-specific growth patterns and growth charts and present new weight-for-age and stature-for-age growth charts for CP. The new charts are based on data comprising over 100,000 measurements of weight and height of children with CP who received services from the California Department of Developmental Services from 1988 to 2002. The charts are stratified by Gross Motor Function Classification System (GMFCS) level. The percentile curves in the new charts are based on methodology recommended by theWHO (the Box-Cox power-exponential distribution with four parameters was used to construct the percentile curves). The resulting curves show 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles of weight-for-age and stature-for-age separately for boys and girls and GMFCS levels I-V, with level V further separated according to presence of a feeding tube. Very low percentiles of weight (5th or 20th percentile, depending on GMFCS level), below which mortality rates are elevated, are identified in the charts. The format of the charts is similar to that of the CDC general population reference charts for children aged 2-20. The new charts confirm earlier work showing that percentiles of weight-for-age and stature-for-age in CP are substantially lower than corresponding percentiles in the general population. The charts also confirm that weight and stature in CP are strongly associated with level of gross motor functioning. Among the most severely affected children with CP (GMFCS level V), weight and stature percentiles are higher for those with feeding tubes. The chapter reviews evidence from earlier studies linking very high or very low weights in CP to other health outcomes and examines these links relative to percentiles of weight-for-age on the new GMFCS-level-specific growth charts. Practical considerations for using the new charts are discussed and cautionary notes provided. The chapter includes a brief discussion of how the information presented here might apply to other neurological disorders or medical conditions.