Leptin and metabolic syndrome in obese and non-obese children

Metabolic syndrome is characterized by a clustering of metabolic abnormalities: insulin resistance - hyperinsulinemia, dyslipidemia (high triglycerides and low HDL - cholesterol serum concentrations), impaired glucose tolerance and/or type 2 diabetes, and hypertension. The aim of this study was to analyse the role of different variables of metabolic syndrome, including leptin, in 74 non-obese children and 68 children with non-syndromal obesity. As metabolic syndrome variables, we have included body mass index, waist circumference, trunk-to-total skinfolds (%), systolic blood pressure, diastolic blood pressure, glucose, uric acid, fasting insulin, triglycerides and high-density lipoprotein-cholesterol (HDL-C). Factor analysis showed 4 factors in each group. In non-obese children, waist circumference, BMI, fasting insulin, triglycerides, trunk-to-total skinfolds (%), leptin and uric acid loaded positively on factor 1, and HDL-C loaded negatively on this factor; systolic and diastolic blood pressure had high positive loadings in factor 2; HDL-C and leptin showed positive loadings and triglycerides and uric acid, negative loadings in factor 3; and, finally, glucose and insulin showed positive loadings in factor 4. These four factors explained 72.16 % of the total variance in the non-obese group. In obese children, BMI, waist circumference, leptin, diastolic blood pressure and systolic blood pressure loaded positively on factor 1; diastolic blood pressure, trunk-to-total skinfolds (%), uric acid and systolic blood pressure showed high positive loadings in factor 2; fasting insulin, glucose and triglycerides showed positive loadings in factor 3; and, finally, triglycerides showed positive loadings and HDL-C negative loadings in factor 4. These four factors explained 74.18 % of the total variance in the obese group. Our results point to a different homeostatic control of metabolic syndrome characteristics in obese and non-obese children. Leptin seems to play a key underlying role in metabolic syndrome, especially in the obese group.

Resting energy expenditure in children and adolescents: agreement between calorimetry and prediction equations

BACKGROUND AND AIMS

To assess the degree of agreement between indirect calorimetry and five equations commonly used to predict resting energy expenditure (REE) in obese and non-obese children and adolescents.

METHODS

In 116 children and adolescents (57 obese and 59 non-obese) aged between 7.8 and 16.6 years, REE was measured (MREE) by open-circuit indirect calorimetry under standardized conditions. REE was predicted (PREE) in all subjects with equations from the Food and Agriculture/World Health Organization/United Nations University (FAO/WHO/UNU), Maffeis et al., Harris and Benedict, and two from Schofield: one using weight (W) and one using height and weight (H-W). Agreement between indirect calorimetry and equations was assessed following the Bland-Altman method.

RESULTS

In the entire cohort group, only data from FAO/WHO/UNU, Schofield-W and Schofield-HW equations showed non-statistic differences against calorimetry results. When agreement between equations and calorimetry was tested, Schofield-HW equation showed the lowest mean MREE-PREE difference: 3.7 kcal/d (limits of agreement -293 and 300 kcal/d; 95% confidence interval for the bias -24.0 to 31.5 kcal/d) and the best agreement. Group by group, equations which obtained the best agreement were: FAO/WHO/UNU in girls, Schofield-HW in boys, Schofield-HW in obese, and Schofield-W in non-obese.

CONCLUSIONS

Until more accurate prediction equations are developed, we recommend Schofield-HW equations for REE studies with a mixed population of obese and non-obese children and adolescents; however, FAO/WHO/UNU equation may also be useful in girls and Schofield-W equation in non-obese children.

Determinants of resting energy expenditure in obese and non-obese children and adolescents

Resting energy expenditure (REE) is the largest component of total daily energy expenditure. Objectives of this study were to examine whether differences in REE exist after obesity develops in a group of children and adolescents, and to determine the effects of body composition, gender, age, pubertal development and parental obesity on REE. In 116 Caucasian children and adolescents (57 obese and 59 non-obese), aged 7.8 to 16.6 years, REE was assessed by open-circuit indirect calorimetry and different anthropometric variables and bioelectrical impedance were obtained (weight, height, skinfold thicknesses, waist and hip circumferences). Anthropometric indices and body compartments were calculated: the body mass index, surface area (SA), fat-free mass (FFM), fat-mass (FM) and percentage of FM. Differences between obese and non-obese subjects were tested and stepwise multiple regression analysis was performed with REE as dependent variable. Results show that REE was significantly higher in obese than in non-obese children and adolescents but REE/FFM ratio was not significantly different between these groups. In the non-obese group, FFM explained 73.1% of the variability in REE and gender, age and SA added 3.8%, 2.6%, and 2.6% to it, respectively. In the obese group, FFM was also the most powerful predictor of REE with 72.3%, followed by waist circumference and age with 2.5% and 2.1%, respectively. These results show that REE differences between obese and lean children do not seem to justify the maintenance of obesity. The main determinant of REE is FFM in both groups. No significant contribution of FM, pubertal development or parental obesity in REE was found in children and adolescents.

Secular increases in body fat percentage in male children of Zaragoza, Spain, 1980-1995

BACKGROUND

Data on temporal changes on total body fat percentage (TBF%) are scarce, and no such data are known to exist in Spain. The aim of our study was to describe secular increases in TBF% in male children and adolescents of Zaragoza, Spain, from 1980 to 1995.

METHODS

The samples analyzed in the present study have been included in two cross-sectional surveys conducted in 1980 and 1995. The samples selected for the 1980 and 1995 surveys comprised 1553 and 701 male children with ages ranging from 6.0 to 14.9 years. Weight, height, and four skinfold thicknesses were measured. From these measurements we have calculated TBF%.

RESULTS

Concerning body mass index (BMI), we have observed significant increases from 8.5 to 11.5 years, ranging in this age group from 0.80 to 1.45 kg/m(2). TBF% showed significant increases at all age groups, with percentage increases of 2.46% at 13.5 years and 6.03% at 11.5 years.

CONCLUSIONS

We have shown a secular increase in TBF% in children aged 6.0 to 15.0 years that is greater than the increase in BMI. The similarity of our findings for both relative weight and skinfold thickness, even with less significant differences for BMI, suggests that, in children of Zaragoza, Spain, adiposity has increased during the 1980-1995 period.

Secular changes in body fat patterning in children and adolescents of Zaragoza (Spain), 1980-1995

OBJECTIVE

To examine whether children and adolescents of Zaragoza (Spain) are becoming centrally obese to a greater extent than would be predicted by their relative body weights.

DESIGN

Two cross-sectional surveys conducted in 1980 and 1995.

SUBJECTS

The samples selected for the 1980 and 1995 surveys comprised 1553 and 701 male children, and 1311 and 659 female children, respectively, with ages ranging from 6.0 to 14.9 y.

MEASUREMENTS

We measured four skinfold thicknesses (biceps, triceps, subscapular, suprailiac) and calculated some indices of fat patterning: triceps/subscapular skinfolds (T/SS), biceps+triceps/subscapular+suprailiac skinfolds (B+T/SS+SI), and (subscapular+suprailiac/biceps+triceps+subscapular+suprailiac skinfolds)x100 (trunk-to-total skinfolds %).

RESULTS

In males, B+T/SS+SI, and trunk-to-total skinfolds % showed a significant trend to a central pattern of fat distribution from 1980 to 1995, at the ages of 6.5-11.5 y. In females, B+T/SS+SI and trunk-to-total skinfolds % showed a significant trend to a central pattern of fat distribution from 1980 to 1995, at the ages of 6.5 and 7.5 y. Similar results were obtained when we adjusted for BMI values.

CONCLUSION

We have observed a trend to a central pattern of adipose tissue distribution, especially in males and at the youngest ages studied (6-11 y in males, and 6-7 y in females). These observations were independent of trends in BMI.

Sociodemographic factors and trends on overweight prevalence in children and adolescents in Aragón (Spain) from 1985 to 1995

From 1985 to 1995, the Aragón School Health Examination Surveys staff has surveyed the whole population of children (age 6-7 years) and adolescents (age 13-14 years). A total of 90,997 children (age 6-7 years) were examined in the nine cross-sectional surveys conducted between 1985 and 1995. A total of 106,284 adolescents (age 13-14 years) were also examined. We defined overweight when the body mass index was > or = 95th percentile. The measure of association between overweight and the other variables studied was the odds ratio, which was calculated by logistic regression. In the children and adolescents studied, the probability to be overweight was higher in the rural than in the urban areas. In the adolescents, the probability to be overweight was higher in the public than in the private schools. Our results also show a significant increase in the prevalence of overweight children in the region of Aragón (Spain) during the 1985-1995 decade, especially in males. Prevention of overweight in the populations at risk would help reduce social inequality in health, a major challenge for public health policy.

Body mass index, triceps skinfold and waist circumference in screening for adiposity in male children and adolescents

Simple anthropometric measurements and indices are the most commonly used tools for assessing body composition. Only a few papers have examined the sensitivity and specificity of the body mass index (BMI) against total body fat percentage (TBF%) from underwater weighing in children and adolescents. The objective of the study was to evaluate the screening performance of BMI, triceps skinfold thickness and waist circumference for excess TBF%. A total of 175 healthy volunteer males, aged 7.0-16.9 y, participated in the study. TBF% was measured using underwater weighing as the reference method. Receiver operating characteristic (ROC) curves were constructed to assess the value of the three anthropometric measurements as a screening measure for total adiposity. Sensitivity and specificity were calculated at several percentile cut-offs for BMI, triceps skinfold and waist circumference. The areas under the ROC curves were also calculated, and were 0.86 for BMI, 0.90 for triceps skinfold and 0.88 for waist circumference. The point on the ROC curve closest to 1 corresponded to the 70th percentile for BMI, to the 75th percentile for triceps skinfold, and to the 70th percentile for waist circumference.

CONCLUSION

BMI, triceps skinfold and waist circumference predicted total fat content well in male children and adolescents.

Effect of solid surface composition on the migration of tributyltin in groundwater

Tributyltin (TBT) is the most important organotin compound that has been introduced into aquatic ecosystems. A better understanding of its interactions with solid surfaces is essential to estimate the possibilities of TBT migration through subsurface environments. For this purpose, TBT sorption onto a porous matrix of natural origin, a quartz sand as an aquifer material, was studied at low concentration levels with a monodirectional model of column type allowing sequential investigation of sorption and desorption processes. Different treatments of the solid phase were performed by injecting alkaline solutions, NaOH at pH 10.8 or NaClO-NaCl at pH 11.5, by decreasing the ionic strength or by adding kaolinite to change the surface composition and properties. The removal of iron and aluminum (hydr)oxides from the sand surface did not affect so much the sorption (decrease in 14% as compared to sorption on the raw sand). The original use of X-ray photoelectron spectroscopy to control treatment efficiency and to characterize sand surface modifications permitted to relate TBT sorption onto the aquifer material to quartz, the main component of the sand, and clay minerals (mainly kaolinite) present at trace levels at the sand surface. A first attempt of transport modeling with these two surface sites showed the consistency of our assumption. Moreover, estimation of Langmuir-type constants showed that TBT sorption affinity for the quartz surface (KL = 26.7 L micromol(-1)) was much greater than for kaolinite (KL = 6.3 L micromol(-1)).

Increased bone density in sclerosteosis is due to the deficiency of a novel secreted protein (SOST)

Sclerosteosis is a progressive sclerosing bone dysplasia with an autosomal recessive mode of inheritance. Radiologically, it is characterized by a generalized hyperostosis and sclerosis leading to a markedly thickened and sclerotic skull, with mandible, ribs, clavicles and all long bones also being affected. Due to narrowing of the foramina of the cranial nerves, facial nerve palsy, hearing loss and atrophy of the optic nerves can occur. Sclerosteosis is clinically and radiologically very similar to van Buchem disease, mainly differentiated by hand malformations and a large stature in sclerosteosis patients. By linkage analysis in one extended van Buchem family and two consanguineous sclerosteosis families we previously mapped both disease genes to the same chromosomal 17q12-q21 region, supporting the hypothesis that both conditions are caused by mutations in the same gene. After reducing the disease critical region to approximately 1 Mb, we used the positional cloning strategy to identify the SOST gene, which is mutated in sclerosteosis patients. This new gene encodes a protein with a signal peptide for secretion and a cysteine-knot motif. Two nonsense mutations and one splice site mutation were identified in sclerosteosis patients, but no mutations were found in a fourth sclerosteosis patient nor in the patients from the van Buchem family. As the three disease-causing mutations lead to loss of function of the SOST protein resulting in the formation of massive amounts of normal bone throughout life, the physiological role of SOST is most likely the suppression of bone formation. Therefore, this gene might become an important tool in the development of therapeutic strategies for osteoporosis.

Postprandial triglyceridemia in obese and non-obese adolescents. Importance of body composition and fat distribution

BACKGROUND

It has recently been shown that obese adults have a disturbed metabolism of postprandial lipoproteins, resulting in postprandial hypertriglyceridemia. To the best of our knowledge, there are no data about postprandial triglyceridemia in obese and non-obese children and adolescents.

SUBJECTS

12 obese and 12 non-obese adolescents, aged 11.0 to 13.8 years.

METHODS

Body composition and fat distribution (waist-to-hip circumference ratio and triceps/ subscapular skinfold thickness ratio) were assessed by anthropometry. An oral fat tolerance test was carried out, and fasting and postprandial lipid-lipoprotein serum concentrations were measured.

RESULTS

We observed a significant increase in triglyceride serum concentrations 2 and 4 hours after the oral fat load, in both obese and non-obese adolescents. In obese and non-obese adolescents there were significant correlations between some variables of postprandial lipemia and the studied indices of body fat distribution. When we compare postprandial lipemia in adolescents having a central pattern of fat distribution with those having a peripheral pattern of fat distribution, we observed higher variables related to postprandial lipemia in those having a central pattern of fat distribution compared with those with a peripheral pattern (sum of serum triglyceride concentrations: 6.06 vs 4.41, p = 0.0243).

CONCLUSIONS

We present a protocol to study postprandial lipemia in children and adolescents that allowed us to observe significant changes after an oral fat load. Results obtained indicate that the pattern of distribution of adipose tissue may be more important for lipid metabolism disturbances than total adipose tissue per se.

Impact of presentation of research results on likelihood of prescribing medications to patients with left ventricular dysfunction

This study was conducted to evaluate willingness to prescribe medication based on identical data presented in different outcome terms to health professionals of varied discipline, geographic location, and level of training. Cross-sectional survey using a self-administered questionnaire was performed in 400 health professionals (physicians, pharmacists, physicians-in-training, and pharmacy students) in the United States and Europe. Data reflecting a clinical trial were presented in 6 outcome terms: 3 terms describing identical mortality (relative risk reduction, absolute risk reduction, and number of patients needed to be treated to prevent 1 death); and 3 distractors (increased life expectancy, decreased hospitalization rate, and decreased cost). Willingness to prescribe and rank order of medication preference assuming willingness to prescribe were measured. The results of the study showed that willingness to prescribe and first choice preference were significantly greater when study results were presented as relative risk reduction than when identical mortality data were presented as absolute risk reduction or number of patients needed to be treated to avoid 1 death (p <0.001). Increase in life expectancy was the most influential distractor. In conclusion, this study, performed in the era of "evidence-based medicine," demonstrates that the method of reporting research trial results has significant influence on health professionals' willingness to prescribe. The high numerical value of relative risk reduction and the concrete and tangible quality of increased life expectancy exert greater influence on health professionals than other standard outcome terms.

Delay in presentation and evaluation for acute stroke: Stroke Time Registry for Outcomes Knowledge and Epidemiology (S.T.R.O.K.E.)

BACKGROUND AND PURPOSE

Early treatment is a critical determinant of successful intervention in acute stroke. The study was designed to find current patterns of stroke care by determining delays in time from onset of signs or symptoms to arrival at the emergency department and to initial evaluation by physicians and by identifying factors associated with these delays.

METHODS

Data were prospectively collected by nurses and physicians from patients, patients' family members, and medical records from 10 hospitals of the Robert Wood Johnson Health System in New Jersey.

RESULTS

A total of 553 patients who presented with signs or symptoms of acute stroke were studied. Thirty-two percent of patients arrived at the emergency department within 1.5 hours of stroke onset. Forty-six percent of patients arrived within 3 hours and 61% within 6 hours. Delays in arrival time were significantly associated with sex, race, transportation mode, and history of cardiovascular disease. Patients arriving by ambulance were more likely to present earlier (odds ratio [OR] 3.7 for arrival within 3 hours; OR 4.5 for arrival within 6 hours). Patients arriving by ambulance (OR 2.3 within 15 minutes; OR 1.7 within 30 minutes) and those requiring admission to intensive care units (OR 4.5 within 15 minutes and OR 5.2 within 30 minutes) were examined sooner by physicians.

CONCLUSIONS

Despite national efforts to promote prompt stroke evaluation and treatment, significant delays still exist. The lack of improvement throughout the past decade underscores the need for implementation of effective public health programs designed to minimize the time to evaluation and treatment of stroke.

Liver cirrhosis is reverted by urokinase-type plasminogen activator gene therapy

Liver cirrhosis represents a worldwide health problem and is a major cause of mortality. Cirrhosis is the result of extensive hepatocyte death and fibrosis induced by chronic alcohol abuse and hepatitis B and C viruses. Successful gene therapy approaches to this disease may require both reversal of fibrosis and stimulation of hepatocyte growth. Urokinase-type plasminogen activator (uPA) may serve this function, as it is an initiator of the matrix proteolysis cascade and induces hepatocyte growth factor expression. In a rat cirrhosis model, a single iv administration of a replication-deficient adenoviral vector encoding a nonsecreted form of human uPA resulted in high production of functional uPA protein in the liver. This led to induction of collagenase expression and reversal of fibrosis with concomitant hepatocyte and improved liver function. Thus, uPA gene therapy may be an effective strategy for treating cirrhosis in humans.

Dietary fat intake and body mass index in Spanish children

Our objectives were to describe the pattern of dietary fat intake and to present data on trends of growth in Spanish children in past decades. In 1984 a nationwide nutritional survey was conducted in Spain. The average nationwide fat intake was 42% of energy. Across different regions, saturated fat intakes ranged from 13% to 15% of energy and monounsaturated fat intakes ranged from 18% to 19% of energy. More recently, some surveys were conducted at a regional or local level. In children aged 6-10 y, total fat intake ranged from 38% to 48% of energy, of which saturated fat intake ranged from 16% to 18% and monounsaturated fat ranged from 19% to 20%. In children aged 11-14 y, total fat intake ranged from 41% to 51% of energy, of which saturated fat intake ranged from 12% to 18% and monounsaturated fat intake accounted for 20%. In our region of Aragón, we observed a significant trend in children's growth, especially when we accounted for body mass index. The results reflect an increasing total fat consumption in Spain, especially of saturated and monounsaturated fat. The following question remains unanswered: what percentage of fat intake should be recommended when monounsaturated fat is the principal source of fat? Trends on body mass index values in children of our region during the past decades could be related to the amount of fat intake in our population. To confirm these findings we must measure dietary fat intake and nutritional status in the same population of children and adolescents.

Lymphocyte T subset counts in children with hypercholesterolemia receiving dietary therapy

BACKGROUND

In children with hypercholesterolemia, dietary therapy is indicated; however, we do not know if a low-fat diet can modify some organic functions, i.e. immune function.

METHODS

42 children with hypercholesterolemia received a low-fat, low-cholesterol diet during 6 months. At baseline and after the treatment period, we determined a lipoprotein profile and some immune characteristics: immunoglobulins G, A and M; complement components (C3, C4 and factor B), and blood lymphocyte subsets (CD3, CD4 and CD8).

RESULTS

Total cholesterol serum concentrations showed a significant reduction after 6 months of dietary therapy (p = 0.008). After 6 months on a low-fat diet, lymphocyte T subset counts (CD3, CD4 and CD8) showed significant decreases (p < 0.01 to p < 0.003), but lymphocyte counts were always within normal ranges. There was also a significant correlation between changes in some lymphocyte T subset counts (CD3 and CD8) and changes in triglyceride serum concentrations (p < 0.05).

CONCLUSIONS

A low-fat, low-cholesterol diet diminished CD3, CD4 and CD8 lymphocyte subset counts that are elevated in children with hypercholesterolemia. Dietary therapy, with emphasis on the intake of n-3 fatty acids, could be useful in the modulation of the immune response at the atheromatous plaque level.

Severe Yellowing Outbreaks in Tomato in Spain Associated with Infections of Tomato chlorosis virus

Since 1997, yellowing disease outbreaks have occurred in tomato (Lycopersicon esculentum) crops in southern Spain. The outbreaks were associated with high populations of the whitefly Bemisia tabaci. Symptoms consisted mainly of interveinal yellowing that developed initially on lower leaves and then progressed to the upper part of the plant. Affected plants were less vigorous and yielded less due to reduced fruit growth and delayed ripening. During 1998 and 1999, the yellowing disease was widespread and occurred at high incidences in the Málaga province. The disease agent was readily transmissible from tomato to tomato by B. tabaci biotype Q. Samples from symptomatic tomato plants were analyzed and shown to be infected with Tomato chlorosis virus (ToCV) (genus Crinivirus, family Closteroviridae). This is the first report of ToCV epidemics in Europe.

[Pseudotumor cerebri associated with maxillary sinusitis: clinico-pathological study]

INTRODUCTION

The pseudotumor cerebri is characterized by increased intracranial pressure in the absence of a space occupying lesions or obstruction to the circulation of cerebrospinal fluid (CSF). Increased pressure but normal composition of the CSF is the diagnostic criterion. Ear infections and other infections such as sinusitis have been cited as possible, but rare, causes.

CLINICAL CASE

A 12 year old girl presented with diplopia 10 days after starting treatment for sinusitis. On examination there was paresia of the VI cranial nerve to the left eye and marked bilateral papilledema. She had normal visual acuity with visual field measurements showing increased blind spot field in both eyes. Resonance studies only showed maxillary sinusitis. CSF pressure was 35 cm H2O, with 40 lymphomonocytes and normal biochemical findings. After 15 cm of CSF had been removed treatment was started with acetazolamide, dexamethasone and cefotaxime. A week later the diplopia had disappeared and the CSF pressure was 25, with no cells present. Two months later the visual fields and fundus oculi were normal. After follow-up for one year there was no recurrence.

CONCLUSIONS

We describe a case of pseudotumor cerebri associated with maxillary sinusitis. We do not know whether this is a chance association or whether there was a pathophysiological basis. The possibility should be considered so as to treat the cause or predisposing factor. The initial CSF pleocytosis would support the possibility of a relationship of the pseudotumor with an infectious condition (meningeal irritation or para-infectious pleocytosis meningeal irritation or para-infections pleocytosis in the context of an ENT infection), which might have precipitated the problem by interfering with the reabsorption of CSF.

Trends in body mass index and overweight prevalence among children and adolescents in the region of Aragón (Spain) from 1985 to 1995

OBJECTIVE

To analyse trends in body mass index (BMI) and overweight prevalence for children and adolescents in the region of Aragón (Spain), from 1985 to 1995.

DESIGN

Nine cross-sectional examinations of schoolchildren conducted yearly from 1985 to 1995.

SUBJECTS

A total of 90,997 children (45,970 males and 45,027 females) in the first school year (6-7 y of age); 106,284 scholars (52,772 males and 53,512 females) in the last school year (13-14 y of age).

MEASUREMENTS

Heights and weights were measured and BMI (kg/m2) was calculated.

RESULTS

We observed a trend to higher BMI values across the surveys, by sex and age. The secular trends in BMI showed the largest increases at the upper ends of the distribution, especially in males. In children in the first school year, prevalences of overweight were higher in females than in males (P<0. 001); however, in adolescents in the last school year, prevalences were higher in males than in females (P<0.001). We observed a significant trend in overweight prevalence from 1985 to 1995 in children from the first school year (P=0.0183, in males and P=0.0168, in females). In children in the last school year there was only a significant trend in males (P<0.0001).

CONCLUSION

Significant changes in BMI occurred in the population studied during the period 1985-1995, but these changes differ by age and sex. The increasing skewness of BMI in the upper percentiles of the population, especially in boys, suggests that, not only is the pediatric population getting fatter, but the fatter members are becoming more obese. Our results also show a striking increase in the prevalence of overweight children in the region of Aragón (Spain) during the 1985-1995 decade.

Serum leptin concentrations in children with Prader-Willi syndrome and non-syndromal obesity

There is limited information on the underlying physiological mechanisms promoting obesity in patients with Prader-Willi syndrome (PWS). The aim of this study was to investigate whether body fat regulation in children with PWS is similar to that in children with non-syndromal obesity and non-obese children. We studied three groups: 1) 72 non-obese children and adolescents; 2) 68 children with non-syndromal obesity; and 3) 11 patients with PWS. Height and weight were measured and body mass index (BMI) and BMI SDS were calculated. Fasting serum leptin concentrations were determined. Median leptin serum concentrations were similar in PWS patients and children with non-syndromal obesity. Median leptin serum concentrations were higher in these two groups than in the non-obese group. Log leptin serum concentrations and BMI SDS showed significant correlations in the three groups of patients; correlation coefficients were 0.525, 0.285 and 0.854, respectively. In conclusion, median leptin serum concentrations are similar in PWS patients and children with non-syndromal obesity. The relationship between log serum leptin concentrations and BMI SDS was different in the three groups of patients studied.

Assessment of nutritional status and body composition in children using physical anthropometry and bioelectrical impedance: influence of diurnal variations

BACKGROUND

To observe whether there are diurnal variations when assessing children's body composition, using physical anthropometric and bioelectrical impedance (BI) methods.

METHODS

In 32 children (18 females and 14 males) aged between 7.1 and 14.9 years, weight, height, arm circumference (AC), four skinfolds, and total body impedance (Z) were measured at 8 A.M., 12 noon, 4 P.M., and 8 P.M. on the same day. Body mass index (BMI), skinfolds sum (SS), total body water (TBW), fat-free mass (FFM), and fat mass (FM) were also calculated at these times.

RESULTS

Height at 8 P.M. was 1.156 +/- 0.54 cm less than at 8 A.M. (P < 0.001) and BMI increased 0.434 +/- 0.29 kg/m2 at 8 P.M. (P < 0.001). Weight, SS and AC underwent no significant changes in the course of the day. Z was 5.83% less at 8 P.M. than at 8 A.M. (P < 0.001), yielding a TBW and FFM increase at 8 P.M. of 0.855 +/- 1.061 and 1.173 +/- 1.47 kg, respectively (P < 0.001).

CONCLUSIONS

In children there is a diurnal decrease in height, impedance and FM, and an increase in BMI, TBW, and FFM. These factors must be taken into account when using such methods for assessing nutritional status in childhood.