Assessment and correction of skinfold thickness equations in estimating body fat in children with cerebral palsy.

AIM: To assess the accuracy of skinfold equations in estimating percentage body fat in children with cerebral palsy (CP), compared with assessment of body fat from dual energy X-ray absorptiometry (DXA). METHOD: Data were collected from 71 participants (30 females, 41 males) with CP (Gross Motor Function Classification System [GMFCS] levels I-V) between the ages of 8 and 18 years. Estimated percentage body fat was computed using established (Slaughter) equations based on the triceps and subscapular skinfolds. A linear model was fitted to assess the use of a simple correction to these equations for children with CP. RESULTS: Slaughter's equations consistently underestimated percentage body fat (mean difference compared with DXA percentage body fat -9.6/100 [SD 6.2]; 95% confidence interval [CI] -11.0 to -8.1). New equations were developed in which a correction factor was added to the existing equations based on sex, race, GMFCS level, size, and pubertal status. These corrected equations for children with CP agree better with DXA (mean difference 0.2/100 [SD=4.8]; 95% CI -1.0 to 1.3) than existing equations. INTERPRETATION: A simple correction factor to commonly used equations substantially improves the ability to estimate percentage body fat from two skinfold measures in children with CP.

Puberty, statural growth, and growth hormone release in children with cerebral palsy.

OBJECTIVE: Children with cerebral palsy (CP) are smaller than normally growing children.. The association between the growth hormone (GH) axis and growth in children with CP during puberty is unknown. We compared growth and markers of the GH axis in pre-pubertal and pubertal children with moderate to severe CP and without CP over a three-year period. STUDY DESIGN: Twenty children with CP, ages 6-18, Gross Motor Function Classification System levels III-V, were compared to a group of sixty-three normally growing children of similar age. Anthropometry, Tanner stage, bone age, and laboratory analyses were performed every six months for three years. Laboratory values included spontaneous overnight GH release, fasting IGF-1 and IGFBP-3. Repeated measures models were used to evaluate interactions among Tanner stage and group (children with CP vs. reference children), taking into account gender, age, and nutritional status. RESULTS: Children with CP grew more slowly than those without CP at all Tanner stages (p<0.01). Patterns of IGF-1 and GH secretion in children with CP were similar to those of the reference group; however, the concentrations of IGF-1 (p<0.01) and GH (p<0.01) were lower in girls with CP, with a similar trend for boys (p=0.10 and 0.14, respectively). CONCLUSIONS: Diminished circulating IGF-1 and GH concentrations may explain the differences in growth between the two groups.

Intensity, perception, and descriptive characteristics of chronic pain in children with cerebral palsy.

OBJECTIVES: Children with cerebral palsy (CP) experience bodily pain, leading to functional impairment and decreased quality of life. The purpose of this study is to characterize subjective descriptors of chronic pain in children with CP. METHODS: One hundred fifty-seven children were invited to participate in a quantitative pilot survey. Parents were mailed the Varni-Thompson Pediatric Pain Questionnaire, designed to assess three dimensions of pain: sensory (physical aspects), affective (emotional response), and evaluative (the combined intensity of the emotional and physical responses). Parents assessed their child's pain using non-verbal and verbal cues. RESULTS: Fifty-two families responded (33% return rate). Thirty-eight children ages 6-8 years with CP and Gross Motor Function Classification System (GMFCS) levels I-V were included. Ninety percent of families reported that their child was experiencing some pain at the time of the survey. At the time of assessment the children's pain was mild. Their pain, at its worst, was in the distressing range. The two largest GMFCS groups of children, levels I and IV, were compared in both severity and intensity of pain experienced. Increasing intensity of pain was reported in children in the level IV group compared to children classified as level I. Pain severity in all dimensions was reported as increasing in Level IV children compared to Level I. DISCUSSION: Children with CP experience frequent pain, which increases with worsening impairment. Descriptive qualifiers of pain help to elucidate the etiology of various types of pain which would lead to the development of more effective approaches to pain management and treatment.

Bodily pain and health-related quality of life in children with cerebral palsy.

Pain frequency and its association with participation, function, and health-related quality of life were evaluated in a sample of 198 children (58% male; mean age 10 years 7 months, SD 3 years 11 months; range 5 to 18 years) with moderate to severe cerebral palsy (CP). Gross Motor Functional Classification System (GMFCS) levels were III to V (23% level III, 23% level IV, 31% level V without a gastrostomy tube, and 23% were level V with a gastrostomy tube). Assessment was carried out using the parent-report Child Health Questionnaire (CHQ) and questions assessing health, medical utilization, and medication use. Pain frequency ranged from 'none' to 'every day'. Eleven percent of parents reported pain almost every day (z score=-0.38, p<0.001). Pain was related to severity of motor impairment and the presence of a gastrostomy; parents of the most severely affected children reported the highest pain frequency (p=0.05). Pain was correlated with school days missed (p=0.03) and days in bed (p=0.01). Children taking gastrointestinal medications were reported to have greater pain frequency (p<0.001). The Parental Impact--Emotional subscale of the CHQ was correlated with reported pain (r=0.38, p<0.001). Pain was frequent in children with moderate or severe CP. Pain was more prevalent with more severe impairment and was associated with educational and social consequences.

Secondary sexual characteristics in children with cerebral palsy and moderate to severe motor impairment: a cross-sectional survey.

OBJECTIVES: To compare the development of secondary sexual characteristics in children with cerebral palsy (CP) of moderate to severe motor impairment to children in the general population and to relate their sexual maturation to a measure of their body fat. METHODS: A multicenter, cross-sectional survey of 207 children who were 3 to 18 years of age and had CP of moderate to severe motor impairment (Gross Motor Functional Classification System [GMFCS] levels 3, 4, and 5) was conducted at 6 geographic sites; attempts were made to identify all eligible children through multiple methods and enroll them in the study. Trained research assistants performed anthropometric measurements, including subscapular skinfold thickness, determined GMFCS level, and assessed sexual maturation by Tanner stage. Secondary sexual characteristics were compared with the general population of children using cross-sectional surveys of the American Academy of Pediatrics Pediatric Research in Office Settings network and of the National Center for Health Statistics National Health and Nutrition Examination Survey (NHANES) III. Girls were classified as having begun puberty when they were at Tanner stage 2 or greater for pubic hair and breast development and to have completed puberty when they were at Tanner stage 4 or greater for pubic hair and breast development. Boys were classified as having begun puberty when they were at Tanner stage 2 or greater for pubic hair and genital development and to have completed puberty when they were at Tanner stage 4 or greater for pubic hair and genital development. RESULTS: The mean age (standard deviation) of subjects was 9.6 (4.6) years. Of the 207 subjects, 71% were white, 21% were black, and 8% were of other races; 59% were boys, and 41% were girls. Girls with CP (n = 84) entered puberty earlier than did boys with CP (n = 123). In contrast, girls with CP tended to complete puberty later than did boys with CP. Black boys and girls with CP (n = 43) entered puberty earlier than did white boys and girls with CP (n = 147). No difference between races was found in completion of puberty. Only for white children with CP were there a sufficient number of subjects for comparisons of sexual maturation to race-matched children in the general population, using data from the American Academy of Pediatrics Pediatric Research in Office Settings network and the NHANES III study. White girls with CP initiated pubic hair development (Tanner stage 2 or greater) earlier than in the general population, but the age of onset of breast development was similar to the general population, although the age distribution was different. A greater proportion of white girls with CP had early onset of breast development (Tanner stage 2 or greater), and a greater proportion had delayed onset of breast development than in the general population. White girls with CP completed breast development later than in the general population but not pubic hair development. For white boys ages 8 to 18 years with CP (n = 75), pubic hair and genital development both began earlier than in the general population, but genital development was completed later. The estimated median age of menarche for white girls with CP was 14.0 years, which was 1.3 years later (95% confidence interval: 0.7-2.3) than for the general population (estimated median age: 12.8 years; NHANES III). Relationships between sexual maturation and nutritional state, as assessed by subscapular skinfold thickness z score, were determined separately in white boys and in white girls with CP, between the ages of 8 and 18 years. For white girls with CP, more advanced sexual maturation was associated with more body fat, adjusting for age and GMFCS level (Spearman partial correlation: 0.41). In contrast, for white boys with CP, the opposite relationship pertained: more advanced sexual maturation was associated with less body fat (-0.29). CONCLUSIONS: The pattern of sexual maturation in children with CP of moderate to severe motor impairment differs from that of children in the general population. Puberty begins earlier but ends later in white children with CP, compared with white children in the general population. In addition, menarche occurs later in white girls with CP. More advanced sexual maturation was associated with more body fat in girls but less body fat in boys.