Is prepubertal growth adversely affected by sport?

PURPOSE: To study the effect of genetic factors, birth weight, early childhood growth, sport, hours of training, and pubertal status on the stature and body mass index (BMI) of children aged 9-13 participating in sports at a competitive level. METHODS: A total of 184 children (96 girls, 88 boys), competing in swimming, tennis, team handball, and gymnastics, were investigated, assessing their height, weight, pubertal development, and BMI. Of these, 137 (76 girls, 61 boys) returned a questionnaire, which enabled us to determine height and BMI at age 2-4, birth weight, and parental heights. RESULTS: Significant differences in standard deviation scores (SDS) for actual height and for height at age 2-4 were found in both sexes between the four sports. In girls, BMI SDS was significantly different between the four sports, whereas no difference was found in boys. Each sport investigated separately showed no change in height SDS and BMI SDS between ages 2-4 and 9-13. A regression analysis showed that target height, height at age 2-4, and pubertal status had a significant impact on actual height. Interestingly, the type of sport and hours of training per week had no effect on height SDS. In boys, BMI at age 2-4 and pubertal status had a significant effect on actual BMI, whereas in girls, only BMI at age 2-4 was significant. CONCLUSIONS: The results suggest that prepubertal growth is not adversely affected by sport at a competitive level and that constitutional factors are of importance for choice of sport in children.     

Ultrasound of the appendix in children: is the child too obese?

The negative influence of obesity on the detection rate of the appendix for US in adults has been reported. It has been assumed that obesity is a limiting factor in the detection of the appendix with US in children as well, but this has not yet been proven. The aim of our study was to evaluate whether nutritional condition (defined by the body mass index-for-age percentiles: BMI-FAP) influences the detection of the appendix in children on US. One hundred twenty-six children (65 girls and 61 boys) with a mean age of 11.4 years with clinically suspected acute appendicitis underwent ultrasound on a commercially available high-end machine (HDI 5000, ATL, Bothell, Wash.). The BMI was calculated, and children were divided in three weight groups in accordance with the BMI-FAP, and were correlated with US findings. Evaluation of the three weight groups in accordance with the BMI-FAP demonstrated significant differences (p=0.04) in the detection of the appendix. There was no statistical significance for the BMI, weight, height, and age solely for the detection of the appendix. In children there is a correlation between the nutritional condition as defined by the BMI-FAP and the detection of the appendix. Electronic Publication     

Immunological changes in response to exercise: influence of age, puberty, and gender

PURPOSE: This study tested the hypothesis that exercise-induced perturbation and recovery of the immune system would vary with age, puberty, and gender in healthy children and adolescents. METHODS: Twelve-year-old girls (YG; N = 14) and boys (YB; N = 20), and 14-yr-old girls (OG; N = 11) and boys (OB; N = 13) cycled for 60 min at 70% VO2max. Blood was collected before, at 30 and 60 min of exercise, and at 30 and 60 min of recovery to measure total leukocytes, leukocyte and lymphocyte subsets, and cytokines. Age and pubertal (Tanner stage) effects within genders and gender effects within age and pubertal groups were determined. RESULTS: Exercise-induced increases in lymphocytes, CD3-CD16+CD56+ counts, and IL-6 were approximately 83, 90, and 390% greater in OG versus YG (P < 0.05). Recovery leukocytosis and neutrophilia were approximately 56 and 35% greater in OB versus YB (P < 0.05). Pubertal stage did not have a statistically significant influence on responses in girls, but the lowest pubertal stage consistently showed smaller changes in lymphocytes and CD3-CD16+CD56+ counts. Recovery neutrophilia was approximately 120% greater in postpubertal boys versus prepubertal or pubertal boys (P < 0.05). Responses of lymphocytes and CD3-CD16+CD56+ counts, respectively, were approximately 120 and 82% greater in OG versus OB (P < 0.05), with no differences between YG and YB. Exercise-induced increases in total leukocytes, lymphocytes, and CD3-CD16+CD56+ counts were at least 35% greater in girls versus boys of similar pubertal status (P < 0.05). Regardless of age, puberty, or gender, IL-8 levels were significantly higher during recovery versus rest (P < 0.05). CONCLUSION: These results highlight the need to control for age, puberty, and gender when interpreting immunologic responses to exercise in a pediatric population.     

Physical heights of children with prolonged low dose-rate γ-radiation exposure in radiocontaminated buildings

Purpose : To evaluate low dose-rate radiation effects on the physical heights of children staying in apartments with 60 Co-contaminated steel construction. Materials and methods : Children who once resided in radiocontaminated apartments since early 1983 were examined for height and body weight status from age 1 month to 18 years and before they moved out of the apartments. The physical heights and body weights of 21 898 age- and sex-matched non-exposed children from a nationwide school surveillance in 1997-98 were taken as controls. The physical height data were shown as height percentiles (HP) compared with reference children and agespecific relative height differences (RHD). Results : HP and RHD in 48 exposed boys and 37 girls were analysed using generalized estimating equations (GEE), which accounted for multiple measurements and correlation between these measurements in the same individuals during this period. After adjusting for effects from parental heights and body mass index (BMI), clear dose-related decreases in HP and RHD were observed in the exposed boys with a cumulative exposure > 60 mSv. Conclusions : Prolonged low dose-rate γ-radiation exposure was associated with adverse effects on the physical heights of growing boys, but were less apparent in the exposed girls.     

Physical heights of children with prolonged low dose-rate gamma-radiation exposure in radiocontaminated buildings

PURPOSE: To evaluate low dose-rate radiation effects on the physical heights of children staying in apartments with 60Co-contaminated steel construction. MATERIALS AND METHODS: Children who once resided in radiocontaminated apartments since early 1983 were examined for height and body weight status from age 1 month to 18 years and before they moved out of the apartments. The physical heights and body weights of 21 898 age- and sex-matched non-exposed children from a nationwide school surveillance in 1997-98 were taken as controls. The physical height data were shown as height percentiles (HP) compared with reference children and age-specific relative height differences (RHD). RESULTS: HP and RHD in 48 exposed boys and 37 girls were analysed using generalized estimating equations (GEE), which accounted for multiple measurements and correlation between these measurements in the same individuals during this period. After adjusting for effects from parental heights and body mass index (BMI), clear dose-related decreases in HP and RHD were observed in the exposed boys with a cumulative exposure > 60 mSv. CONCLUSIONS: Prolonged low dose-rate y-radiation exposure was associated with adverse effects on the physical heights of growing boys, but were less apparent in the exposed girls.     

Bone mass in healthy children: measurement with quantitative DXA

Dual-energy x-ray bone densitometry was used to study the lumbar vertebral bone mass in 218 healthy children (134 girls and 84 boys) aged 1-19 years. Vertebral bone mass increased with weight, age, and pubertal Tanner stage. Results of multiple regression analyses showed that Tanner stage and weight were the best predictive indicators of bone mass and bone mineral density. The influences of age, sex, race, physical activity, and diet were not significant when Tanner stage and weight were controlled. Two tables of predictive intervals for lumbar vertebral bone mineral density in healthy children (one based on Tanner stage and weight; the other, on age and weight) are presented. With normative data now available for use with this precise technique, clinicians can better detect abnormal bone mineral density in children and evaluate changes in mineralization over time.     

Spleen length in childhood with US: normal values based on age, sex, and somatometric parameters

PURPOSE: To investigate with ultrasonography (US) normal spleen length in healthy children. MATERIALS AND METHODS: The study comprised 512 healthy children (274 girls) with ages ranging from 1 day (full-term neonate) to 17 years who were examined between 1996 and 2001. The main sample comprised 454 children (249 girls) with body measurements (weight and height) between the 5th and 95th percentiles of the relevant growth curves. The remaining 58 children (25 girls) with body measurements outside the normal ranges formed a separate sample used for cross-validation. None had a problem that could affect spleen size. The relationships between the US-measured spleen length and age and body parameters were studied with nonlinear regression and multiple (backward stepwise) regression techniques. Normal ranges and related statistics were estimated and tabulated according to age group and sex. Spleen length growth curves and upper limits defined by the 90% upper confidence limit (UCL) are presented in graphs according to height, weight, and body surface area (BSA). RESULTS: Spleen length was highly correlated with age, height, weight, and BSA; there was no statistically significant difference between the sexes. The exact pattern of these relationships was nonlinear (polynomial type of third order for age, height, and weight and exponential type for BSA). Multiple regression analysis indicated that age, height, and either weight or BSA had significant positive associations with spleen length. The spleen lengths among the sample of 58 children whose height and weight were outside the normal ranges of growth parameters did not influence the proposed upper limits (almost all were within the 90% UCLs with respect to height and weight for the main sample). CONCLUSION: Normal spleen lengths and ranges in childhood were obtained with US in a large sample of individuals.     

上海城区7～17岁正常、超重和肥胖学生20米往返跑成绩比较

目的:比较上海城区7~17岁正常、超重和肥胖学生20米往返跑(20mSRT)成绩,了解体质指数不同对学生有氧耐力成绩的影响。方法:采用分层随机整群抽样方法,抽取上海城区7~17岁身体健康的中小学生4687名(男2362名,女2325名),按年龄、性别分组同时对受试者的测试动机和测试条件等容易影响测试结果可靠性的各种因素进行了控制。先测试受试者身高、体重等形态学指标,准备活动后测试20mSRT。严格按照Leger方法进行测试。参照中国肥胖工作组中国学龄儿童青少年(7~18岁)超重肥胖筛查体重指数值分类标准,对受试者的超重和肥胖进行分类。结果:7~17岁各年龄段男生20mSRT成绩为正常体重组>超重组>肥胖组(P<0.01),7~17岁各年龄段女生20mSRT成绩为正常体重组>超重组>肥胖组(P<0.01),且男生体重正常组、超重组和肥胖组20mSRT成绩的组间差距比女生更大。按青春期前、中、后分组,7~10岁组、11~14岁组和15~17岁组男生20mSRT成绩均为正常体重组>超重组>肥胖组(P<0.01);女生除7~10岁组超重与肥胖组间无显著性差异(P>0.05)以外,11~14岁组和15~17岁组女生20mSRT成绩均为正常体重组>超重组>肥胖组(P<0.01);且7~10岁组、11~14岁组和15~17岁组男生20mSRT成绩受体重影响均大于女生各组。结论:无论男生或者女生,7~17岁各年龄段的学生20mSRT成绩在正常体重组、超重组和肥胖组依次递减,且男生体重正常组、超重组和肥胖组的组间差距比女生大;按青春期年龄分组后,男生和女生体重变化对20mSRT成绩仍有影响。因此,适当控制体重对提高儿童青少年的20mSRT成绩可能有积极作用。     

Vertebral bone density in children: effect of puberty

To determine changes in bone density during growth, trabecular vertebral density and an index of spinal cortical bone were measured with quantitative computed tomography in 101 children. The children were divided by age into three groups: prepubertal, indeterminate, and pubertal. Compared with prepubertal children, pubertal adolescents had significantly higher trabecular bone density and more compact bone in the spine (P less than .001). After controlling for puberty, vertebral bone density failed to correlate significantly with age, sex, weight, height, surface area, and body mass index. The results indicate that bone density increases markedly during puberty.     

BMI and health-related physical fitness in Taiwanese youth 9-18 years

PURPOSE: The purpose of the study was to evaluate the cross-sectional relationship between BMI and a physical fitness index (PFI) based on four indicators of fitness in a national sample of Taiwanese youth. METHODS: Height, weight, and four measures of physical fitness (sit-ups completed in 60 s, standing long jump, sit and reach, and 800- or 1600-m run/walk) were measured in a national sample of 102,765 Taiwanese youth 9-18 yr of age: 50,940 girls and 51,825 boys. BMI was calculated for each subject. Within each sex-specific half-year age group, students were classified into five BMI categories based on national percentiles: very low, BMI < 5th percentile; low, BMI >or= 5th but < 15th percentiles; normal, BMI >or= 15th but < 85th percentiles; high, BMI >or= 85th but < 95th percentiles; and very high, BMI >or= 95th percentiles. Z-scores based on sex- and age-specific means and standard deviations were calculated, and the sum of z-scores for the four fitness tests was used as a PFI. Differences in PFI between BMI categories within each sex-specific half-year age group were compared with ANOVA with Bonferroni adjustments. Sex-specific regressions of PFI on BMI, using a nonlinear quadratic model, were done in four broader age categories. RESULTS: Relationships between BMI and PFI are nonlinear and vary with age from late childhood through adolescence. With increasing age during adolescence, the relationship becomes parabolic, and the peaks of the parabola are sharper in adolescent boys than girls. CONCLUSION: PFI declines in a curvilinear manner with increasing BMI among youth 9-18 yr of age, but the slope of the relationship varies with age.     

Renal interlobar artery parameters with duplex Doppler sonography and correlations with age, plasma renin, and aldosterone levels in healthy children

OBJECTIVE: The objectives of this study were to compare and make correlations between age and Doppler parameters of the interlobar arteries, including synchronously obtained plasma renin and aldosterone levels and to obtain new normative data regarding acceleration time in healthy children from neonates to 16 years. SUBJECTS AND METHODS: One hundred sixty-nine healthy children (72 girls and 97 boys) were classified into four groups: group 1 (< 1 year; n = 34), group 2 (range, 1-6 years; n = 48), group 3 (range, 6-12 years; n = 50), and group 4 (range, 12-16 years; n = 37). Blood samples from the renin and aldosterone were collected in the morning after bed rest and fasting. The resistive index (RI), pulsatility index (PI), and the acceleration time of the renal interlobar arteries with duplex Doppler sonography, including both kidney longitudinal lengths with grayscale sonography, were evaluated. One-way analysis of variance with the least significant difference post-hoc test and Pearson's correlation test were used to compare the differences between groups and to make correlations, respectively. An independent-sample t test was used to evaluate the differences between all parameters based on sex and to compare the left and right kidney longitudinal lengths in each group. RESULTS: The RI, PI, and acceleration time were statistically significant in between-group comparisons. Only in group 4 was acceleration time not statistically significant compared with groups 2 and 3. Plasma renin levels were significantly higher in group 1 compared with groups 2 (p < 0.03) and 4 (p < 0.0001); in group 2 compared with group 4 (p < 0.05); and in group 3 compared with group 4 (p < 0.01). The plasma aldosterone levels were significantly higher only in group 1 compared with groups 2 (p < 0.001), 3 (p < 0.008), and 4 (p < 0.0001). The RI correlated linearly with the PI, plasma renin levels, and aldosterone levels and correlated inversely with acceleration time. Age had a negative correlation with the RI, PI, plasma renin levels, and aldosterone levels and correlated positively with acceleration time. There were no statistically significant differences between all parameters based on sex and no significant difference found between the right and left kidney longitudinal lengths in each group. CONCLUSION: The RI in children up to 54 months old is higher than in adults. Therefore, the adult mean renal RI criterion of 0.70 should be applicable to children 54 months old and older. We showed that the age dependency of the RI was directly related to that of plasma renin and aldosterone levels in healthy children in whom Doppler parameters and blood analysis were evaluated synchronously.     

Thyroid Doppler indices in patients with sickle cell disease

ObjectiveTo evaluate the intrathyroidal hemodynamic changes and thyroidal volume in sickle cell disease (SCD) patients.MethodsThirty-two patients with homozygous SCD and 32 control subjects were examined with color Doppler ultrasonography. None of the patients and control subjects had clinical or laboratory evidence of thyroid disease.ResultsSCD patients had significantly higher resistance index (RI) and pulsatility index (PI) values and lower thyroid volume compared with control group.ConclusionIncreased intrathyroidal RI and PI and decreased thyroid volume may be due to impaired thyroidal microcirculation. Further and follow-up studies are needed to explain the relationship between Doppler parameters and thyroid functions.     

自填式青春期发育量表(中译版)的检验

目的:验证自填式青春期发育量表(中译版)的可靠性和有效性。方法:选取153名11～14岁健康中学生(男79人,女74人)填写量表,通过量表的总分相关系数和内部一致性检验反映量表的信度。量表的效度检验方法为,选取32名11～14岁健康受试者(男20名,女12名),使其同时完成量表填写和骨龄片的拍摄,运用Pearson相关分析确定效标系数,说明量表得分与骨龄的相关一致性,P<0.05具有统计学意义。结果:自填式青春期发育量表(中译版)三个记分条目的总分相关系数,男性分别为0.49、0.51和0.40,女性分别为0.55、0.63和0.65;男、女生量表的克朗巴哈α系数分别是0.63和0.72。男、女生量表得分与骨龄呈高度相关,相关系数分别为0.614(P<0.01)、0.798(P<0.01)。结论:自填式青春期发育量表(中译版)具有较高的内部一致性,可以有效评估中国学生青春期的发育阶段。     

Renal duplex Doppler ultrasonography as a predictor of preclinical diabetic nephropathy in children.

PURPOSE: To perform Doppler US in patients with insulin-dependent diabetes mellitus (IDDM) as a predictive method in diabetic nephropathy (DN). MATERIAL AND METHODS: Twenty-five patients with type I diabetes mellitus underwent renal Doppler US examination. Children were divided into three age groups: group I, 3-7 years; group II, 8-10 years; and group III, 11-18 years. The age-matched control group consisted of 56 healthy children who underwent renal Doppler US only. RESULTS: The mean values of the resistive index (RI) were, respectively, 0.64+/-0.03, 0.59+/-0.04, 0.59+/-0.02 in age groups I, II, and III for healthy children and 0.68+/-0.03, 0.62+/-0.04, 0.59+/-0.04 in age groups I, II, and III of the diabetic patients. There were no significant differences between the diabetic and healthy subjects. The mean RI value was not different in the patients with glomerular hyperfiltration compared to patients with normal filtration rate. Additionally, there were no significant differences between the mean RI value in patients with or without microalbuminuria. CONCLUSION: Renal Doppler US is not useful for prediction or for early diagnosis of DN.     

Pedometer-determined physical activity and body composition in New Zealand children

PURPOSE: The objectives of this study were to examine current levels of pedometer-determined physical activity in a multiethnic sample of New Zealand children and to investigate associations among weekday and weekend step counts, body mass index (BMI), waist circumference (WC), and percentage body fat (%BF). METHODS: A total of 1115 children (536 boys, 579 girls) aged 5-12 yr wore sealed multiday memory pedometers for three weekdays and two weekend days. The ethnic composition of the sample was 49.2% European, 30.0% Polynesian, and 16.5% Asian, with 4.3% from other ethnicities. BMI was determined from height and weight, and %BF was measured using hand-to-foot bioelectrical impedance analysis. Participants were classified as normal weight, overweight, or obese using international BMI cutoff points (4), and into normal or central fat distribution groups using national WC standards (28). The 90th percentile of %BF for each age and sex subgroup was used to identify normal and high body fatness. RESULTS: Mean step counts for this sample were 16,133 +/- 3,864 (boys) and 14,124 +/- 3,286 (girls) on weekdays, and 12,702 +/- 5,048 (boys) and 11,158 +/- 4,309 (girls) on weekends. Significant differences in step counts were observed between weekdays and weekends, boys and girls, and among age, ethnic, and socioeconomic groups. Analysis of variance revealed stronger associations between step counts and %BF category than between step counts and BMI or WC groups. CONCLUSION: This study provides evidence of a link between daily step counts and body fatness in children. Our results also suggest that the promotion of physical activity during the weekend is a key priority for young New Zealanders.     

青春期女性骨密度变化及相关影响因素分析

目的:分析9～16岁女性骨密度(BMD)值的差异及相关影响因素。方法:随机选取广西省桂林市和广东省广州市714名青春发育期女性(9～16岁) ,采用跟骨超声骨密度仪测量BMD ,采用问卷调查了解对骨密度有影响的生活因素。结果:青春期女性BMD 12岁较9岁高4 4 % ,14岁较12岁高6 . 0 % ,16岁较14岁高2 5 % ;户外活动时间超过6小时/周的女性BMD值高于不足6小时/周者(P <0 . 0 5 ) ;摄入牛奶量≥1杯/天(2 0 0ml/杯)的女性BMD值高于摄入不足1杯/天者(P <0 .0 5 ) ;月经初潮早的女性BMD值比月经初潮晚的女性高(P <0 . 0 5 )。逐步回归分析表明,对青春期女性BMD有影响的因素为月经来潮年限、体重和牛奶摄入量。结论:12～14岁是青春期女性BMD的快速增长期,青春期女性身高增长与BMD增长不同步;月经初潮晚于平均年龄的女性BMD值低;积极参加户外活动对青春期女性BMD积累有一定作用;维持适宜的体重和一定量牛奶的摄入有利于提高青春期女性BMD和达到理想的峰值骨量。     

Role of color Doppler indices in predicting disease-free survival of breast cancer patients during neoadjuvant chemotherapy

The aim of our study was to evaluate whether blood flow in locally advanced and inflammatory breast cancer before and after neoadjuvant chemotherapy using color Doppler ultrasonography can be used to monitor the response to therapy and identify possible correlations between survival and various Doppler indices. Fifty patients with breast cancer underwent Doppler evaluation of the tumor with determination of Doppler indices such as pulsatility index (PI), resistive index (RI), and peak systolic velocity (PSV). RI and PI decreased in 27 (54%) and 20 (40%) patients, respectively, and increased in 23 (46%) and 30 (60%) patients, respectively. Thirty (60%) patients showed a decrease in PSV and 20 (40%) patients an increase. Patients with an intratumoral blood flow velocity increase after chemotherapy had a greater likelihood of local recurrence and metastasis compared with patients in whom flow velocity decreased after chemotherapy. The study also confirmed a greater correlation between Doppler PSV and clinical assessment. Tumor flow velocity measured by Doppler ultrasound can be used as an independent marker of disease-free survival in patients with breast cancer.     

Stenosis of the renal artery: assessment of slowed systole in the downstream circulation with Doppler sonography.

Slowing and dampening of systole in the arterial network distal to stenosis is a well-known Doppler sign of severe arterial stenosis. To determine whether this sign is present in boys and girls with such stenosis, intrarenal Doppler curves (acceleration index [AI] and resistive index [RI]) were compared with findings on renal arteriograms in 20 boys and girls; the AI was also measured in 10 boys and girls without renal disease. Statistical analysis of AI and RI measurements was performed. Eleven of 32 renal arteries were normal. The normal AI was 4.0-7.0; in arteries with greater than 75% stenosis, the AI was 0.7-1.7. In five arteries studied after angioplasty, the AI had changed from 0.7-1.5 to 4.0-5.6 at the first posttreatment examination (performed 28 hours to 1 week after angioplasty), and it remained normal during the 3-year follow-up period. In kidneys with stenotic arteries, the RIs were lower (0.43-0.54) than in healthy subjects (0.56-0.63). Regression and correlation coefficients of AI and RI measurements were statistically significant, and discrimination between normal arteries and those with greater than 75% stenosis was excellent.     

Reference values for Doppler ultrasound parameters of the thyroid in a healthy iodine-non-deficient population

The aim of this study was to describe normal Doppler parameter values in the thyroid arteries in an iodine-replete region. 165 individuals were randomly selected in a community located in the south-east of Brazil. We obtained a clinical history on each subject and determined serum thyrotropin, antiperoxidase antibodies, thyrotropin receptor antibody (TRAb) and thyroid volumes through ultrasound. Subjects with thyroid disease and those under 20 years of age were excluded. 84 representative subjects (30 men and 54 women) remained. The systolic peak velocity (SPV), resistive index (RI) and pulsatility index (PI) in the superior and inferior thyroid arteries were measured using a 5-12 MHz linear probe. Except for the RI, the distribution of all Doppler parameters was non-gaussian. The median and mean references for the SPV, RI and PI were 24.80 cm s(-1) and 25.85 cm s(-1), 0.60 and 0.62, and 0.98 and 1.04, respectively, for superior thyroid arteries; these reference values for the inferior thyroid artery were 20.92 cm s(-1) and 21.50 cm s(-1), 0.57 and 0.57, and 0.84 and 0.88, respectively (p<0.001). Women had greater SPV values (p<0.01). We have determined reference thyroid Doppler parameter values in our iodine-non-deficient population and prepared tables by sex and age.     

Le développement et la croissance pubertaires normaux

Onset of puberty is due to successive changes in neuroendocrine, pituitary and gonadal activity with a final impact on peripheral steroid receptor response. The occurrence of a pulsatile LH secretion derived by a neuroendocrine mechanism is characteristic of the onset of puberty. The first signs of puberty occur at a mean age of 11.5 years in girls and 12.5 years in boys. Puberty is accompanied by an increased growth rate reaching a mean value of peak height velocity of 9 cm/year. In girls, the mean height gained after menarche is 7 cm. It is likely that in normal children the age at onset of puberty is not correlated with the final height, according to evaluations made by the Bayley-Pinneau technique using the Greulich and Pyle bone age assessment. However chronic diseases occuring at time of onset or during puberty may impair the rate of growth and reduce the final height.