Childhood bone mass acquisition and peak bone mass may not be important determinants of bone mass in late adulthood

During childhood and adolescence, bone mass acquisition occurs primarily through skeletal growth. It is widely assumed that bone mass acquisition throughout childhood is an important determinant of the risk of osteoporosis in late adulthood; bone mass is thought to resemble a bank account in which deposits persist indefinitely. However, several well-controlled clinical studies suggest that increasing bone mass acquisition during childhood will have only transient effects. A likely explanation is that bone mass is governed by a homeostatic system that tends to return to a set point after any perturbation and, therefore, bone mass depends primarily on recent conditions, not those in the distant past. Indeed, in an animal model, we have shown evidence that bone mass acquisition in early life has no effect on bone mass in adulthood, in part because many areas of the juvenile skeleton are replaced in toto through skeletal growth. Therefore, it should not be assumed that alterations in childhood bone mass acquisition will affect bone mass many decades later in late adulthood. This issue remains open and the solution may depend on the type of childhood condition (for example calcium intake versus exercise) and its magnitude, timing, and duration. To date, both animal studies and clinical studies suggest that much of the effect of early bone mass acquisition does not persist.     

Risk of irregular menstrual cycles and low peak bone mass during early adulthood associated with age at menarche

BACKGROUND: The risk of irregular menstrual cycles and low peak bone mass of the lumbar spine in young adult women, associated with age at menarche, has not been clearly defined. The aim of this study was to investigate this further. METHODS: A total of 180 college females aged 20-23 years were surveyed about menstruation, exercise, and calcium intake by means of a questionnaire. We also measured vertebral bone mineral density in these women by dual energy X-ray absorptiometry. The subjects were divided into six groups according to their age at menarche. Comparisons were made of the mean body mass index (BMI) and T-scores (the ratio to the mean bone mineral density of young adult Japanese women) among those groups, and odds ratios of irregular menstrual cycles and low peak bone mass less than 87% (- 1 standard deviation (SD) of T-scores were calculated using the mean menarcheal age (12 years) group as a control. RESULTS: The mean BMI and T-scores were significantly lower in delayed menarche groups (equal to or more than 13 years) compared with early menarche groups (equal to or less than 12 years). The odds ratios of irregular menstrual cycles were 5.9 (95% confidence intervals (CI) 1.7-20.6), 13.7 (95% CI 3.6-51.6), and 73 (95% CI 6.5-813.9) in the 13-, 14-, and more than 14 years menarcheal age groups, respectively. The odds ratio of low peak bone mass less than 87% (- 1SD) was 3.4 (95% CI 1.1-10.3) in the 14 years menarcheal age group. CONCLUSIONS: Young adult women with delayed menarche may be at high risk for irregular menstrual cycles and low peak bone mass.     

Overweight/obesity and factors associated with body mass index during adolescence: the VYRONAS study

Aim: To describe overweight and obese adolescents and to determine any correlations between an adolescent's body mass index (BMI) with personal (age, gender), lifestyle (sedentary/sport activities, smoking status) and parental (smoking status, BMI, number of cars) characteristics.
Methods: Cross-sectional data on weight, height and various characteristics from 2008 Greek adolescents (12- to 17-year olds, 50.85% boys), measured in 2005–2007, were used.
Results: Almost 1 in 5 (19.2%) boys and 1 in 7 (13.2%) girls 12–17 years of age were overweight while 4.4% of the boys and 1.7% of the girls were obese. The adolescents' age, mother's smoking status, father's and mother's BMI predicted boys' and girls' BMI (b = 0.551, 0.203, 0.110, 0.495 for boys, b = 0.233, 0.187, 0.180, 0.531 for girls, respectively, p ≤ 0.05). Univariate analysis revealed that television watching/using personal computer/playing video games and playtime were not correlated with BMI, while an inverse association of exercising for ≥ 5 h/week and BMI was found in both boys and girls (b =−1.098, −0.528, p = 0.005, 0.004 respectively).
Conclusion: The results of our study underline the high prevalence of obesity during adolescence in Greece. Age and parental unhealthy behaviour (increased BMI and maternal smoking status) were positive predictors of increased BMI of adolescents in both genders.     

Effect of central precocious puberty and gonadotropin-releasing hormone analogue treatment on peak bone mass and final height in females

To evaluate the effect of central precocious puberty (CPP) and its treatment with gonadotropin-releasing hormone (GnRH) analogues on final height and peak bone mass (PBM), we measured lumbar bone mineral density (BMD) in 23 girls at final height. Patients were distributed in two groups. Group 1: 14 patients with progressive CPP were treated with GnRH analogues; seven patients received buserelin (1600 μg/daily), subsequently switched to depot triptorelin (60 μg/kg/26–28 days); seven patients were treated with depot triptorelin (60 μg/kg/26–28 days); mean age of treatment was 6.2 years (range 2.7–7.8 years); the treatment was discontinued at the mean age of 10.1 years (range 8.7–11.3 years); final height was reached at the mean age 13.4 years (range 12.0–14.9 years). Group 2: 9 patients (mean age 6.5 years, range 4.8–7.7 years) with a slowly progressing variant of CPP were followed without treatment; final height was reached at the mean␣age␣13.6 years (range 12.5–14.8 years). Lumbar BMD (L₂-L₄ by dual energy X-ray␣absorptiometry) was measured in all patients at final height. In group 1, final height␣(158.9 ± 5.4 cm) was significantly greater than the pre-treatment predicted height (153.5 ± 7.2 cm, P < 0.001), but significantly lower than mid-parental height (163.2 ± 6.2 cm, P < 0.005). Subdividing the girls of group 1 according to the bone age at discontinuation of therapy (i.e. ≤11.5 years, n = 5, or ≥12.0 years, n = 9), the former patients had a final height significantly higher than the latter (163.7 ± 3.9 cm vs 156.5 ± 4.6 cm, P < 0.02). In group 2, final height (161.8 ± 4.6 cm) was similar to the pre-treatment predicted height (163.1 ± 6.2 cm, P = NS) and was not significantly different from mid-parental height (161.0 ± 5.9 cm). BMD values (group 1: 1.11 ± 0.14 g/cm², group 2: 1.22 ± 0.08 g/cm²) were not significantly different from those of a control group (1.18 ± 0.10 g/cm²; n = 20, age 16.3–20.5 years) and the patients' mothers (group 1: 1.16 ± 0.07 g/cm², n = 11, age 32.9–45.1 years; group 2: 1.20 ± 0.08 g/cm², n = 7, age 33.5–46.5 years). In group 1, the girls who stopped therapy at a bone age ≤11.5 years had significantly higher BMD (1.22 ± 0.10 g/cm²) compared to those who discontinued therapy at a bone age ≥12.0 years (1.04 ± 0.12 g/cm², P < 0.05). Conclusion In girls with progressive CPP, long-term treatment with GnRH analogues improves final height. A subset of patients with CPP does not require treatment because good statural outcome (slowly progressing variant). In CPP, the abnormal onset of puberty and the long-term GnRH analogue treatment do not impair the achievement of PBM. In GnRH treated patients, the discontinuation of therapy at an appropriate bone age for pubertal onset may improve both final height and PBM. Received: 5 June 1997 / Accepted in revised form 21 November 1997     

Effects of thalassemia major on bone mineral density in late adolescence

Management of thalassemia major has shown substantial clinical and prognostic improvement, suggesting the need for major attention to quality of life. We studied bone health in 25 patients (13 males, 12 females; 15-23 years old) affected by beta-thalassemia major. In all patients, bone mineral density (BMD), biochemical markers of bone and calcium metabolism (calcium, phosphate, magnesium, alkaline phosphatase, urinary calcium, 25-hydroxyvitamin D [25OH-D], 1,25-dihydroxyvitamin D [1,25(OH)2D], parathyroid hormone [PTH]), hematological parameters and gonadal steroids status were assessed and related to each other and to auxological parameters (chronological, statural and bone ages, height, weight, stage of puberty). BMD of the lumbar spine (L1-L4) (g/cm2) and expressed as Z-scores, was assessed by dual energy X-ray absorptiometry. PTH levels were low in seven patients (28%), and in the normal range in 18 (72%). 25OH-D serum levels were normal in 16 patients (64%) and low in nine (36%). 1,25(OH)2D values were reduced in 19 patients (76%) and normal in six (24%). Alkaline phosphatase correlated with bone age delay (r = 0.414; p = 0.039); no other statistically significant correlation was found. Mean BMD values in patients with thalassemia were significantly reduced in comparison with that of age- and sex-matched controls (Z-score: -2.8 +/- 2.0, p <0.001; -3.3 +/- 2.1 in males, and -2.2 +/- 1.9 in females). Twenty-one patients (84%) showed reduced BMD. Overall, BMD reduction was in the osteopenia range in five patients (20%) and in the osteoporosis range in 16 patients (64%). Our data indicate that low BMD is often present in patients with thalassemia, although recognized late, as in the present series. Early diagnosis should be done during childhood, in order to improve the quality of life in adulthood.     

Physical activity and bone development during childhood and adolescence. Implications for the prevention of osteoporosis

Osteoporotic fractures are a debilitating and a frequently fatal health problem for older adults. A growing body of evidence indicates that osteoporosis has its origin in early life and that the level of development of bone mass during childhood and adolescence strongly influences the risk for osteoporotic fractures. The development of osteoporosis results from an interaction between 1) bone mass accrual via growth, remodeling, and modeling during childhood and adolescence and 2) the maintenance of bone mass (primarily via remodeling) during adulthood. Peak bone mass which occurs at the conclusion of growth may be the most important factor for preventing osteoporosis since as much bone is accrued during the adolescent years as most individuals will lose during all of adult life. In this review, I examine the contribution of physical activity as an important behavioral determinant of children's bone development, particularly of peak bone mass. Since it is a behavior, physical activity is a potentially modifiable determinant of peak bone mass; therefore, understanding activity's impact on bone health is central to developing primary prevention strategies for osteoporosis.     

Effects of increased red cell mass on subclinical tissue acidosis in hyaline membrane disease.

AIM: To determine whether there are subclinical deficits in oxygen delivery in ventilated premature neonates. METHOD: Ventilated premature neonates weighing less than 1500 g, who were transfused for anaemia or who were given colloids for clotting abnormalities (or oedema), were haemodynamically monitored during the first week of life. Calf muscle surface pH (pH) was measured in conjunction with peripheral limb blood flow by occlusion plethysmography. RESULTS: Packed red blood cell transfusions corrected a subclinical regional tissue acidosis (low tpH) without affecting arterial pH or limb blood flow. This observation also correlated with an increase in regional oxygen delivery. The data were also suggestive of a pattern of pathological, supply dependent, oxygen delivery and are similar to other observations made in adults with adult respiratory distress syndrome. CONCLUSIONS: Packed red blood cells increase regional oxygen delivery and tissue surface pH. In contrast, colloid infusion provided no substantial cardiovascular or metabolic benefit to these patients and should be avoided when oxygen delivery is at issue and when there may be leaky pulmonary capillaries.     

新生儿期至青春期血中肉碱和酰基肉碱的变化

目的 用串联质谱测定不同年龄儿童血中游离肉碱和各种酰基肉碱浓度,为诊断肉碱缺乏和各种有机酸和脂肪酸代谢病奠定基础.方法 研究对象是围产期新生儿1376例,大于1周的新生儿49例,小于1岁的婴幼儿64例,1～15岁儿童401例.围产期新生儿是无选择的产院出生儿,包括了少量早产儿和低出生体重儿.其余主要是排除了发热、腹泻、肝病、严重疾病等影响脂肪代谢的门诊小手术的体检儿童.用非衍生法前处理滤纸血片,串联质谱测定其中游离肉碱和30种酰基肉碱浓度.结果 游离肉碱(C0)、短链酰基肉碱(C2、C3、C4、C5)、中链酰基肉碱(C6、C8、C 10)及其烯酰基、羟基、二酰基肉碱和总肉碱水平新生儿阶段较低,1～3个月时最高,之后降低,2～15岁在相同水平维持.长链酰基肉碱(C12、C14、C16、C18)及其烯酰基肉碱、羟基酰基肉碱及其总和新生儿阶段最高,逐渐降低,2～15岁在相同水平维持.游离肉碱浓度(23.387±7.702)μmol/L,(30.064±8.252)μmol/L,(25.021±6.630)μmol/L,总长链酰基肉碱浓度(4.998±1.557)μmol/L,(2.854±0.821)μmol/L,(2.459±0.553)μmol/L,肉碱酰基肉碱总浓度(43.497±12.632)μmol/L,(49.013±12.497)μmol/L,(39.656±9.257)μmol/L在新生儿组、小于1岁组和大于1岁组差异有统计学意义(P＜0.01).围产期新生儿男婴组肉碱(24.115±7.715)μmol/L和肉碱和酰基肉碱总和(43.65±5.252)μmol/L分别高于女婴(22.696±7.246)μmol/L和(41.90±5.038)μmol/L(P＜0.05).新生儿组游离肉碱占总肉碱比值(54.0%±7.1%)明显小于非新生儿组(62.1%±6.1%,P＜0.05),而长链(33.5%±6.0%)、中链(1.3%±0.3%)和短链脂酰基肉碱(11.6%±2.5%)与总肉碱比值分别高于非新生儿组(30.1%±4.9%;0.9%±0.6%;6.5%±2.3%,P＜0.05).结论 1岁以内血中肉碱和酰基肉碱水平和构成变化较大,在评价肉碱营养状态和诊断有机酸和脂肪酸代谢病时要考虑年龄因素.围产期新生儿男婴肉碱和酰基肉碱略高于女婴.     

Bisphosphonate therapy for reduced bone mineral density during treatment of acute lymphoblastic leukemia in childhood and adolescence: a report of preliminary experience

BACKGROUND: Osteopenia is a common consequence of the treatment of acute lymphoblastic leukemia (ALL) in children and adolescents, due predominantly to glucocorticosteroid therapy. The pathogenesis relates to an imbalance of resorption over formation of bone. METHODS: Alendronate (Fosamax), an inhibitor of osteoclastic bone resorption, was administered for at least 6 months to 15 children with ALL during maintenance chemotherapy, after the diagnosis of osteopenia/osteoporosis by dual energy x-ray absorptiometry. The height velocity was also measured during the administration of alendronate and again 2 years later. RESULTS: Areal bone mineral density Z scores of the lumbar spine had a median value of -1.32 before administration of alendronate and a median gain of +0.64, with 14/15 children showing improvement. There was no adverse effect of alendronate on height velocity, and the drug was well tolerated with no short-term toxicity. CONCLUSIONS: This preliminary experience suggests a potential value in the use of alendronate for the treatment of osteopenia/osteoporosis in children with ALL and points to the need for a randomized controlled trial of this intervention.     

The developmental course of anxiety symptoms during adolescence: the TRAILS study

Background:  Little is known about the development of anxiety symptoms from late childhood to late adolescence. The present study determined developmental trajectories of symptoms of separation anxiety disorder (SAD), social phobia (SoPh), generalized anxiety disorder (GAD), panic disorder (PD), and obsessive-compulsive disorder (OCD) in a large prospective community cohort.
Methods:  Anxiety symptoms were assessed in a community sample of 2220 boys and girls at three time-points across a 5-year interval. The Revised Child Anxiety and Depression Scale (RCADS) was used to assess anxiety symptoms, and multilevel growth-curve analyses were performed.
Results:  All subtypes of anxiety first showed a decrease in symptoms (beta for age ranged from –.05 to –.13, p  < .0001), followed by a leveling off of the decrease, and a subsequent slight increase in symptoms (beta for age-squared ranged from .006 to .01, p  < .0001) from middle adolescence (GAD, SoPh, SAD) or late adolescence (PD and OCD) onwards. This increase in anxiety symptoms could not be explained by a co-occurring increase in depression symptoms. Girls had more anxiety symptoms than boys, and this difference remained stable during adolescence ( p  < .0001). Gender differences were strongly attenuated by adjustment for symptoms of depression.
Conclusions:  The current study shows that, in the general population, anxiety symptoms first decrease during early adolescence, and subsequently increase from middle to late adolescence. These findings extend our knowledge on the developmental course of anxiety symptoms during adolescence. This is the first study to separate the development of anxiety symptoms from that of symptoms of depression.     

Low bone mass in prepubertal children with thalassemia major: insights into the pathogenesis of low bone mass in thalassemia

OBJECTIVE: Low bone mass occurs frequently in the aging thalassemic population. However, limited information exists on bone mass in children with thalassemia major (TM) during their first decade of life. STUDY DESIGN: Spinal bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DEXA) in 18 children (age 5.8 +/- 1.5 yr; M:F 8:10) with TM on hypertransfusion and iron chelation therapy. Serial BMD measurements were available for 11 of the 18 children. RESULTS: Weight and height z scores were 0.81 +/- 4.2 and -0.47 +/- 1.7 respectively. At the first BMD, four (22.2%) patients presented with BMD z scores less than -2.5, seven (38.8%) had BMD z scores between -1 and -2.5, while the remaining seven (38.8%) had normal BMDs (z score above -1). The mean decline of BMD z score was -0.38/year (p = ns). BMD z scores correlated with height z scores (p = 0.039), but not with liver enzymes, serum ferritin levels, or thalassemia genotypes. CONCLUSIONS: Low bone mass is present in most children with TM despite hypertransfusion and optimal chelation, adequate growth and lack of endocrine complications.     

Evaluating the effect of childhood and adolescence asthma on the household economy

ObjectiveTo evaluate the relationship between asthma control, family income and family costs of asthma in a population of children-adolescents; to detail the family costs of asthma in this age range; and to compare asthma costs for the families of children-adolescents and adults.MethodsThe authors invited asthmatic subjects who attended a scheduled spirometry test at the Jundiaí School of Medicine (FMJ). The FMJ performs all spirometry tests requested by staff physicians who serve at the public healthcare system in the municipality. Volunteers responded to the ACQ, the Asthma Family Costs Questionnaire and underwent a spirometry test.ResultsThe authors included 342 children-adolescents. Families of children-adolescents taking maintenance therapy and families of those reporting uncontrolled asthma symptoms were more likely to report any expenditure with asthma during the preceding month. In this age range, the smallest expenditures were on diagnostic tests and medical consultations, while home expenditures to avoid asthma triggers were the highest ones. As compared to adults’ families, the children and adolescents families reported a greater proportion of income committed with asthma. Expenditures with transportation to healthcare facilities for asthma care were greater in the families of children-adolescents as compared to the values reported by the adults’ families; in contrast, loss of income due to asthma was smaller in the families of children-adolescents.ConclusionsChildren-adolescents’ asthma affects the household economy. The authors believe researchers should assess this outcome when designing studies about asthma. Finally, the study's data support the necessity of public policies in low-resource communities to minimize the economic impact of children and adolescents’ asthma.