Lean body mass (LM) has been positively associated with bone mineral density (BMD) in children and adolescents, but the relationship between body fat mass (FM) and BMD remains controversial. Several biomarkers secreted by adipose tissue, skeletal muscle, or bone may affect bone metabolism and BMD. We investigated the associations of LM, FM, and such biomarkers with BMD in children. We studied a population sample of 472 prepubertal Finnish children (227 girls, 245 boys) aged 6-8years. We assessed BMD, LM, and FM using whole-body dual-energy x-ray absorptiometry and analysed several biomarkers from fasting blood samples. We studied the associations of LM, FM, and the biomarkers with BMD of the whole body excluding the head using linear regression analysis. LM (standardized regression coefficient β=0.708, p<0.001), FM (β=0.358, p<0.001), and irisin (β=0.079, p=0.048) were positive correlates for BMD adjusted for age, sex, and height in all children. These associations remained statistically significant after further adjustment for LM or FM. The positive associations of dehydroepiandrosterone sulphate (DHEAS), insulin, homeostatic model assessment for insulin resistance (HOMA-IR), leptin, free leptin index, and high-sensitivity C-reactive protein and the negative association of leptin receptor with BMD were explained by FM. The positive associations of DHEAS and HOMA-IR with BMD were also explained by LM. Serum 25-hydroxyvitamin D was a positive correlate for BMD adjusted for age, sex, and height and after further adjustment for FM but not for LM. LM and FM were positive correlates for BMD also in girls and boys separately. In girls, insulin, HOMA-IR, leptin, and free leptin index were positively and leptin receptor was negatively associated with BMD adjusted for age, height, and LM. After adjustment for age, height, and FM, none of the biomarkers was associated with BMD. In boys, leptin and free leptin index were positively and leptin receptor was negatively associated with BMD adjusted for age, height, and LM. After adjustment for age, height and FM, 25(OH)D was positively and IGF-1 and leptin were negatively associated with BMD. FM strongly modified the association between leptin and BMD. LM but also FM were strong, independent positive correlates for BMD in all children, girls, and boys. Irisin was positively and independently associated with BMD in all children. The associations of other biomarkers with BMD were explained by LM or FM.

ICS use during childhood may be related to a decrease in BMD at late school age. It is important to use the lowest possible ICS dose that maintains adequate asthma control.

ContextRecombinant human FSH (r-hFSH), given to prepubertal boys with hypogonadotropic hypogonadism (HH), may induce Sertoli cell proliferation and thereby increase sperm-producing capacity later in life.ObjectiveTo evaluate the effects of r-hFSH, human chorionic gonadotropin (hCG), and testosterone (T) in such patients.Design and SettingRetrospective review in three tertiary centers in Finland between 2006 and 2016.PatientsFive boys: ANOS1 mutation in two, homozygous PROKR2 mutation in one, FGFR1 mutation in one, and homozygous GNRHR mutation in one. Prepubertal testicular volume (TV) varied between 0.3 and 2.3 mL; three boys had micropenis, three had undergone orchidopexy.InterventionsTwo boys received r-hFSH (6 to 7 months) followed by r-hFSH plus hCG (33 to 34 months); one received T (6 months), then r-hFSH plus T (29 months) followed by hCG (25 months); two received T (3 months) followed by r-hFSH (7 months) or r-hFSH plus T (8 months).Main Outcome MeasuresTV, inhibin B, anti-Müllerian hormone, T, puberty, sperm count.Resultsr-hFSH doubled TV (from a mean ± SD of 0.9 ± 0.9 mL to 1.9 ± 1.7 mL; P < 0.05) and increased serum inhibin B (from 15 ± 5 ng/L to 85 ± 40 ng/L; P < 0.05). hCG further increased TV (from 2.1 ± 2.3 mL to 8.6 ± 1.7 mL). Two boys with initially extremely small testis size (0.3 mL) developed sperm (maximal sperm count range, 2.8 to 13.8 million/mL), which was cryopreserved.ConclusionsSpermatogenesis can be induced with gonadotropins even in boys with HH who have extremely small testes, and despite low-dose T treatment given in early puberty. Induction of puberty with gonadotropins allows preservation of fertility.

Background and purpose Recently, obesity has been connected with wheezing, asthma and reduced lung function. Most previous studies have been cross‐sectional. The aim of the present follow‐up study was to evaluate the association of preceding or current overweight or obesity with lung function at early and late school age after early childhood wheezing. Material and methods From the 100 children hospitalized for infection associated wheezing at <24 months of age, 83 attended the control visit at 4.0 years, 82 at 7.2 years and 81 at 12.3 years of age. Flow‐volume spirometry was performed in 79 children at 7.2 years and in 80 children at 12.3 years of age. The weight status was assessed by calculating body mass index (BMI) at all visits. Age‐ and gender‐specific BMI standard deviation scores (BMI–SDS) of >1.3 SD and >2.0 SD were defined to mean overweight and obesity, respectively. Results Overweight at both 7.2 and 12.3 years of age was associated with decreased FEV1/FVC (forced expiratory volume in 1 sec/forced vital capacity). Overweight and obesity at 7.2 years of age were associated with decreased FEV1/FVC and MEF50 (maximal expiratory flow at 50% of FVC) at 12.3 years of age. The results were similar by continuous and categorized analyses, being robust to adjustments for viral findings during early childhood wheezing and asthma maintenance medication at school age. Conclusion Overweight and obesity are significant risk factors for reduced lung function at school age after early childhood wheezing. Thus, early‐life wheezers should avoid excessive weight gain during childhood. Pediatr. Pulmonol. 2011; 46:435–441. © 2010 Wiley‐Liss, Inc.