Subject(s)
Ethanolamines/urine , Hypophosphatasia/diagnosis , Adolescent , Adult , Child , Child, Preschool , Humans , Hypophosphatasia/urine , Infant , Infant, Newborn , Reference Values , Retrospective Studies , Young AdultABSTRACT
BACKGROUND: Children with growth retardation or short stature generally present with lower strength than children of the same chronological age. The aim of the study was to establish if strength was dependent on variables related to stature in a population of healthy children and to propose practical predictive models for the muscle functions tested. A secondary aim was to test for any learning effects concerning strength measured at two successive visits by children. METHODS: Hand grip, elbow flexion and extension, and knee flexion and extension were measured by fixed dynamometry in 96 healthy subjects (47 girls and 49 boys, aged from 5 to 17 years). RESULTS: For the present paediatric population, muscle strength was highly dependent on height. Predictive models are proposed for the muscle functions tested. No learning effect between the first and the second visit was detected for any of the muscle functions tested. CONCLUSIONS: This work shows that strength measurements using fixed dynamometry are reliable in children when using appropriate standardization of operating procedures. It underlines the particular relationship between body stature and muscle strength. Predictive equations may help with assessing the neuromuscular involvement in children suffering from various disorders, particularly those affecting their stature.
Subject(s)
Adolescent Development , Body Height , Child Development , Muscle Development , Muscle Strength , Muscle, Skeletal/physiology , Adolescent , Age Factors , Child , Child, Preschool , Female , Functional Laterality , Hand Strength , Humans , Learning , Male , Muscle Strength Dynamometer , Muscle, Skeletal/growth & development , Physical Examination , Predictive Value of Tests , Reference Values , Reproducibility of Results , TorqueABSTRACT
BACKGROUND AND OBJECTIVE: Most of the cardiovascular risk factors strongly associated with obesity and overweight vary with age and gender. However, few reference values are available for healthy European children. Our objective was to establish pediatric reference ranges for waist circumference, systolic and diastolic blood pressures, fasting lipid levels (total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides), glucose, and insulin. METHODS: A representative sample of 1976 healthy French individuals (1004 female participants and 972 male participants) aged 7 to 20 years was used to obtain age- and gender-specific normal ranges for each of the above-listed cardiovascular risk factors, based on the Royston and Wright method. RESULTS: Mean waist circumference increased with age in both genders and was slightly higher in males than in females. Whereas systolic blood pressure increased gradually with age, with the increase being steeper in males than in females, no gender effect was found for diastolic blood pressure, which was therefore modeled after pooling males and females. Total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglyceride values varied little with age and gender. Glucose and insulin levels revealed pubertal peaks, which were sharper in females than in males, reflecting the normal insulin resistance during puberty. CONCLUSIONS: These ranges can be used as references for European children to monitor cardiovascular risk factors and to plan interventions and education programs.
Subject(s)
Cardiovascular Diseases/etiology , Nutritional Status , Obesity/complications , Patient Education as Topic/methods , Risk Assessment/methods , Adolescent , Blood Glucose/metabolism , Blood Pressure , Body Mass Index , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/prevention & control , Child , Female , France/epidemiology , Humans , Incidence , Insulin/blood , Lipids/blood , Male , Obesity/blood , Obesity/epidemiology , Reference Values , Retrospective Studies , Risk Factors , Young AdultABSTRACT
BACKGROUND: A reference model for converting serum growth factor and bone metabolism markers into an SD score (SDS) is required for clinical practice. We aimed to establish reference values of serum insulin-like growth factor-1 (IGF-1) and IGF binding protein 3 (IGFBP-3) concentrations and bone metabolism markers in French children, to generate a model for converting values into SDS for age, sex, and pubertal stage. METHODS: We carried out a cross-sectional study of 1119 healthy white children ages 6-20 years. We assessed concentrations of serum IGF-1, IGFBP-3, carboxyterminal telopeptide α1 chain of type I collagen (CrossLaps), and bone alkaline phosphatase concentrations and height, weight, and pubertal stage, and used semiparametric regression to develop a model. RESULTS: A single regression model to calculate the SDSs with an online calculator was provided. A positive relationship was found between SDS for serum IGF-1 and IGFBP-3, IGF/IGFBP-3 mol/L ratio, and anthropometric parameters (P < 0.0001), with slightly greater effects observed for height than for body mass index (BMI). There was a negative relationship between serum CrossLaps concentration and BMI, and a positive relationship between serum CrossLaps concentration and height. A comparison of serum IGF-1 reference databases for children showed marked variation as a function of age and pubertal group; smooth changes with age and puberty were observed only in our model. CONCLUSIONS: This new model for the assessment of SDS reference values specific for age, sex, and pubertal stage may help to increase the diagnostic power of these parameters for the assessment of growth and bone metabolism disorders. This study also provides information about the physiological role of height and BMI for the interpretation of these parameters.
