Blood pressure nomograms for children and adolescents, by height, sex, and age, in the United States

Effect of the rs997509 polymorphism on the association between ectonucleotide pyrophosphatase phosphodiesterase 1 and metabolic syndrome and impaired glucose tolerance in childhood obesity

CONTEXT

Variants on the nucleotide pyrophosphatase/phosphodiesterase-1 (ENPP-1) gene have been associated with obesity and insulin resistance. Because insulin resistance is a pivotal factor in the development of metabolic syndrome (MS) and impaired glucose tolerance (IGT), we aimed to test the association between the K121Q and rs997509 ENPP-1 variants with obesity, MS and IGT in obese children and adolescents.

METHODS

We screened 809 children, 409 obese and 400 lean controls. Obese subjects underwent a standard oral glucose tolerance test, whole body insulin sensitivity index (WBISI) and homeostasis model assessment (HOMA) were calculated.

RESULTS

No difference in prevalence for K121Q and rs997509 polymorphisms between obese and controls (P > 0.05) were observed. Obese children carrying the rs997509 rare allele showed higher insulin (P = 0.001), HOMA (P < .001) and lower WBISI values (P = 0.04) compared with common allele homozygous. A similar observation was done for K121Q variant, with 121Q allele carriers showing higher insulin (P = 0.03) and HOMA (P = 0.04) values than 121K homozygotes. Moreover, subjects carrying the rs997509 rare allele had higher risk of MS (odds ratio 2.4, 95% confidence interval: 1.3-4.3) and IGT (odds ratio 4.7, 95% confidence interval: 1.9-11.4) than common allele homozygotes. Evaluating combined effects of both polymorphisms, which are in strong linkage disequilibrium, we showed that the effect on insulin sensitivity was due to the rs997509 T variant.

CONCLUSION

We conclude that the ENPP1 rs997509T allele can predispose obese children to MS and IGT and that this variant might drive the association between the ENPP1 121Q allele and insulin resistance.

Plasma matrix metalloproteinase-9 levels and blood pressure in short children born small for gestational age and effects of growth hormone treatment

CONTEXT

Short small-for-gestational-age (SGA) children have an increased systolic blood pressure (BP) that decreases during long-term GH treatment. The underlying mechanism is still unknown. Matrix metalloproteinases (MMPs) are zinc-dependent endoproteinases that are involved in the remodelling of the extracellular matrix (ECM) and are thought to play a role in atherosclerosis. High MMP-9 levels are found in hypertensive patients and predict cardiovascular mortality.

OBJECTIVES

To investigate whether GH treatment affects plasma MMP-9 levels in short SGA children and whether these are related to BP.

DESIGN

Case-control study.

INTERVENTION

GH treatment vs. no treatment during 36 months. Patients Thirty-eight short SGA children receiving GH treatment vs. 17 sex- and age-matched untreated short SGA controls.

OUTCOME MEASURE

Plasma MMP-9 levels and BP were measured at baseline, and after 6, 12 and 36 months of study.

RESULTS

MMP-9 decreased significantly during 3 years of GH treatment but remained similar in untreated SGA controls. After 3 years of GH treatment, MMP-9 levels were significantly lower in the GH group than in the untreated SGA controls. Systolic BP SDS significantly decreased in the GH group but remained unaltered in the untreated SGA controls. MMP-9 levels did not correlate with systolic or diastolic BP.

CONCLUSIONS

Plasma MMP-9 levels and systolic BP SDS decreased to almost 50% of baseline values in the GH group but remained unchanged in untreated SGA controls. Our data indicate that GH has a positive effect on both MMP-9 levels and systolic BP SDS.

Cardiovascular risk factors in parents of short children born small for gestational age

Small for gestational age (SGA) children have a higher prevalence of cardiovascular risk factors at a young age. It is not known whether this increased risk is caused by their size at birth, a familial predisposition for cardiovascular disease or smallness at birth or a combination of these factors. The cardiovascular risk profile of parents of SGA children is unknown. We compared anthropometry, blood pressure, fasting serum lipid, glucose, and insulin levels of 482 parents (mean age 41 y) and 286 short SGA children with age- and sex-matched references. We also investigated whether these parameters correlated between parents and their offspring. Mothers had higher systolic blood pressure, fathers had a higher body mass index and parents had more frequently high fasting glucose levels than age- and sex-matched references. Children had significantly higher systolic and diastolic blood pressure than sex- and height-matched references. Twenty-four percent (mothers) and 10% (fathers) were born SGA but they did not have more cardiovascular risk factors than those born appropriate for gestational age. Cardiovascular risk factors did not correlate between parents and children. In conclusion, parents of short SGA children have a modest increase in some cardiovascular risk factors but risk factors did not correlate between parents and children.

High prevalence of central adrenal insufficiency in patients with Prader-Willi syndrome

CONTEXT

The annual death rate of Prader-Willi syndrome (PWS) patients is very high (3%). Many of these deaths are sudden and unexplained.

OBJECTIVE

Because most deaths occur during moderate infections and PWS patients suffer from various hypothalamic insufficiencies, we investigated whether PWS patients suffer from central adrenal insufficiency (CAI) during stressful conditions.

DESIGN

Overnight single-dose metyrapone tests were performed. Metyrapone (30 mg/kg) was administered at 2330 h. At 0400, 0600, and 0730 h, ACTH, 11-deoxycortisol, cortisol, and glucose levels were measured. Diurnal salivary cortisol profiles were assessed on a different day at wake-up, 30 min after wake-up, at 1400 h, and at 2000 h.

SETTING

The study was conducted in a pediatric intensive care unit.

PATIENTS

Patients included 25 randomly selected PWS patients.

MAIN OUTCOME MEASURE

Patients were considered as having CAI when ACTH levels remained below 33 pmol/liter at 0730 h.

RESULTS

Median (interquartile range) age was 9.7 (6.8-13.6) yr. Fifteen patients (60%) had an insufficient ACTH response (CAI, P < 0.001). There was no significant difference in age, gender, genotype, and body mass index SD score between patients with CAI and those without. Morning salivary cortisol levels and diurnal profiles were normal in all children, suggesting that CAI becomes apparent only during stressful conditions.

CONCLUSIONS

Strikingly, 60% of our PWS patients had CAI. The high percentage of CAI in PWS patients might explain the high rate of sudden death in these patients, particularly during infection-related stress. Based on our data, one should consider treatment with hydrocortisone during acute illness in PWS patients unless CAI has recently been ruled out with a metyrapone test.

Independent effects of prematurity on metabolic and cardiovascular risk factors in short small-for-gestational-age children

CONTEXT

Both small-for-gestational-age (SGA) and preterm birth have been associated with an increased incidence of adult cardiovascular disease and diabetes mellitus type 2. However, it is unclear whether preterm birth has an additional effect on cardiovascular risk factors in short children born SGA.

OBJECTIVE

Our objective was to investigate whether prematurity has an independent influence on several cardiovascular risk factors within a population of short SGA children.

DESIGN

A cross-sectional observational study was performed.

PATIENTS

A total of 479 short SGA children (mean age 6.8 yr), divided into preterm (<36 wk) and term (> or =36 wk) children, was included in the study.

OUTCOME MEASURE

Insulin sensitivity, beta-cell function, body composition, and lipid levels were studied in subgroups, and blood pressure (BP), anthropometry at birth and during childhood in the total group.

RESULTS

Preterm SGA children were significantly lighter and shorter at birth after correction for gestational age than term SGA children (P < 0.001) but had a comparable head circumference. In preterm SGA children, we found a significantly higher systolic (P = 0.003) and diastolic BP sd score (P = 0.026), lower percent body fat sd score (P = 0.011), and higher insulin secretion (P = 0.033) and disposition index (P = 0.021), independently of the degree of SGA. Insulin sensitivity, serum lipid levels, muscle mass, and body fat distribution were comparable for preterm and term SGA children.

CONCLUSIONS

Within a population of short SGA children, preterm birth has divergent effects on several cardiovascular risk factors. Whereas preterm SGA children had a higher systolic and diastolic BP, they also had a lower percent body fat and a higher insulin secretion and disposition index than term SGA children.

Type 2 diabetes in children and adolescents in a 2-year follow-up: insufficient adherence to diabetes centers

BACKGROUND/AIMS

To study the 2-year course of children and adolescents with type 2 diabetes mellitus (T2DM) in general practice to present (1) the treatment modalities, (2) patient adherence, and (3) the occurrence of comorbidities.

METHODS

HBA1c, lipids, blood pressure, treatment modalities, occurrence of retinopathy and nephropathy were analyzed in 129 children and adolescents with T2DM (median age 13.4 years, 75% female) in specialized diabetes centers in Germany.

RESULTS

Seventy-eight (60%) children dropped out of care after a mean of 7.1 months. Drug treatment was not stopped in any of the 64 children initially treated with antidiabetic drugs. Sixteen (12%) children were treated solely by lifestyle intervention over the 2-year course. In the 51 children with complete follow-up, median HbA1c was 7.7% at diagnosis and 6.3% after 2 years. Less than 5% of all children were treated with antihypertensive or lipid-lowering drugs, while 65% suffered from hypertension and 44% from dyslipidemia. Over the course of the disease, retinopathy was not observed, while microalbuminuria occurred in 25%.

CONCLUSIONS

In general practice, many children and adolescents with T2DM were lost of follow-up. Lifestyle intervention as sole treatment was not often useful for long-term metabolic control. Dyslipidemia and hypertension were seldom treated as recommended.

The evaluation of carotid intima-media thickness in children with familial Mediterranean fever

The aim is to investigate whether pediatric familial Mediterranean fever (FMF) patients have an increased risk of premature atherosclerosis and to determine the possible strength of association between atherosclerosis and Mediterranean fever (MEFV) gene mutation gene type. Demographic characteristics and MEFV mutations were defined in 49 children diagnosed with FMF (26 female, 23 male; mean age, 10.71 +/- 3.69 years). Twenty-six age-, sex-, and body-mass-index-matched healthy children constituted the control group. We evaluated the blood counts and acute-phase proteins during attack-free periods. Mean C-reactive protein (CRP), serum amyloid-A (SAA), homocysteine (Hcy), lipoprotein-a (Lp-a), and common carotid artery intima-media thickness (CCA-IMT) were 10.75 +/- 15.29 vs 4.03 +/- 1.20, 23.22 +/- 41.94 vs 3.53 +/- 1.04, 10.36 +/- 3.36 vs 8.64 +/- 3.15, 20.84 +/- 23.89 vs 8.56 +/- 7.48, and 0.038 +/- 0.007 vs 0.032 +/- 0.004, respectively, and significantly higher than the mean values of control group (p < 0.05). However, no correlation was found between CCA-IMT and CRP, SAA, Hcy, and Lp-a. Twenty-nine patients had M694V mutation, and 13 patients had other mutations. There was no correlation between CCA-IMT and MEFV mutation subgroups. In conclusion, because of the nature of the disease, FMF patients should be considered to have an increased risk of early vascular alteration and atherosclerosis. For this reason, CCA-IMT measurement can be recommended as a noninvasive and early diagnostic method.

Blood pressure in the first year of life in healthy infants born at term

Neonatal hypertension occurs in up to 2% of neonatal intensive care survivors and in up to 3% of all neonates. Normal blood pressure (BP) measurements are required to diagnose and manage appropriately both hypotension and hypertension in the neonate and infant. The aim of this study was to provide normative BP measurements during the first year of life of healthy infants born at term, using an oscillometric method. Neonates were enrolled from August 2003 to August 2005. Exclusion criteria included: infants of mothers with hypertension or diabetes of any type, use of illicit substances, congenital or chromosomal anomaly, admission to the neonatal intensive care unit or possible sepsis. There were 406 infants enrolled, with 150 children followed at 6 months of age and 118 children at 12 months of age. There were no differences in BP measurements at 6 months or 12 months of age by gender, weight or height. A BP measurement above the 90th percentile on day 2 or at 6 months was not predictive of a BP above the 90th percentile at 12 months of age. Higher systolic and diastolic measurements at 6 months and 12 months were found, in comparison to those in previous studies using ultrasonic devices. The findings of this study provide normative BP values for infants during their first year of life, using the oscillometric method, the most frequently used method in paediatric, neonatal intensive care and emergency departments.

Outcomes at 2 years of age after repeat doses of antenatal corticosteroids

BACKGROUND

We previously reported the results of a randomized, controlled trial showing that repeat doses of antenatal corticosteroids reduced the risk of respiratory distress syndrome and serious neonatal morbidity. However, data have not been available regarding longer-term effects of this treatment.

METHODS

Women who had received an initial course of corticosteroid treatment 7 or more days previously were randomly assigned to receive an intramuscular injection of corticosteroid (11.4 mg of betamethasone) or saline placebo; the dose was repeated weekly if the mother was still considered to be at risk for preterm delivery and the duration of gestation was less than 32 weeks. We assessed survival free of major neurosensory disability and body size of the children at 2 years of corrected age.

RESULTS

Of the 1085 children who were alive at 2 years of age, 1047 (96.5%) were seen for assessment (521 exposed to repeat-corticosteroid treatment and 526 exposed to placebo). The rate of survival free of major disability was similar in the repeat-corticosteroid and placebo groups (84.4% and 81.0%, respectively; adjusted relative risk, 1.04, 95% confidence interval, 0.98 to 1.10; adjusted P=0.20). There were no significant differences between the groups in body size, blood pressure, use of health services, respiratory morbidity, or child behavior scores, although children exposed to repeat doses of corticosteroids were more likely than those exposed to placebo to warrant assessment for attention problems (P=0.04).

CONCLUSIONS

Administration of repeat doses of antenatal corticosteroids reduces neonatal morbidity without changing either survival free of major neurosensory disability or body size at 2 years of age. (Current Controlled Trials number, ISRCTN48656428 [controlled-trials.com].).

[Blood pressure measurement in the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). Methodology and initial results]

Hypertension is one of the main risk factors for cardiovascular disease and ranks among the leading causes of morbidity and mortality worldwide. Hypertension in children is rare, but the blood pressure rank in relation to peers is often maintained from childhood into adulthood and is therefore of great public health relevance. For this reason, one of the aims of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) was to collect representative data on blood pressure in children aged 3 to 17 years, in order to create an epidemiological basis for a comprehensive analysis of blood pressure in children and adolescents in Germany. Two oscillometric blood pressure measurements were obtained using an automated device (Datascope Accutorr Plus) and two readings of systolic, diastolic and mean arterial pressure and of heart rate were obtained in a standardised fashion in 14.730 children (7203 girls and 7527 boys). The main aim of this article is a detailed description of the blood pressure measurement in KiGGS, which is important for the interpretation of our findings compared to other studies. Our initial results on the distribution of systolic and diastolic blood pressure confirm previous findings of increasing blood pressure with age and height and of higher systolic blood pressure levels among boys compared with girls from the age of 14 years.

Trends in body mass index, blood pressure and parental smoking habits in middle socio-economic level Turkish adolescents

Patterns of cardiovascular risk factors in populations are not static over time. We examined trends in body mass index (BMI), parental smoking and blood pressure over a 15-year period in Turkish children aged 15-17 years. Two cross-sectional studies were performed in secondary schools in Turkey in 1989-1990 and 2004-2005. Study participants were 673 children in 1989-1990 and 640 adolescents in 2004-2005. Main outcome measures were weight, height, BMI, presence and amount of parental smoking, systolic and diastolic blood pressure. Age and sex matched comparisons were performed to assess temporal trends in these measures. Children in 2004-2005 had increased weight, height, BMI and decreased systolic and diastolic blood pressure in all age groups compared with children in 1989-1990. According to the international criteria, 3.4% of children were obese and 15.8% were overweight in 2005, compared to 0.7% obese and 4.2% overweight in 1990 (P<0.001). However, a decrease was noted in blood pressure; 16% were classified as hypertensive in 1989-1990 versus 8% in 2004-2005 (P<0.001). The prevalence and amount of parental smoking also decreased over the last 15 years. We observed significant changes in BMI and blood pressure in Turkish children over the last 15 years. Temporal trends in these parameters may indicate a change in the pattern of cardiovascular disease in this population.

Has blood pressure increased in children in response to the obesity epidemic?

The associations between elevated blood pressure and overweight, on one hand, and the increasing prevalence over time of pediatric overweight, on the other hand, suggest that the prevalence of elevated blood pressure could have increased in children over the last few decades. In this article we review the epidemiologic evidence available on the prevalence of elevated blood pressure in children and trends over time. On the basis of the few large population-based surveys available, the prevalence of elevated blood pressure is fairly high in several populations, whereas there is little direct evidence that blood pressure has increased during the past few decades despite the concomitant epidemic of pediatric overweight. However, a definite conclusion cannot be drawn yet because of the paucity of epidemiologic studies that have assessed blood pressure trends in the same populations and the lack of standardized methods used for the measurement of blood pressure and the definition of elevated blood pressure in children. Additional studies should examine if favorable secular trends in other determinants of blood pressure (eg, dietary factors, birth weight, etc) may have attenuated the apparently limited impact of the epidemic of overweight on blood pressure in children.

Lower bone mineral content in hypertensive compared with normotensive overweight Latino children and adolescents

BACKGROUND

In adults, hypertension has been shown to be inversely correlated with bone mineral content (BMC); however, the association between blood pressure (BP) and BMC has not been studied in pediatrics.

METHODS

Total body BMC of 187 overweight (mean BMI = 28.7 kg/m(2)) Latino children and adolescents (mean age = 11.2 years) were measured using dual-energy x-ray absorptiometry. Seated systolic BP (SBP) and diastolic BP (DBP) were measured using a standard mercury sphygmomanometer. Hypertension was defined by SBP or DBP above the 90(th) percentile for height, age, and sex.

RESULTS

Partial correlations revealed an inverse association between SBP and BMC (r = -0.24, P = 0.02) in boys (n = 105); results were nonsignificant (P = 0.27) in girls (n = 82). There were no significant correlations between DBP and BMC. When BMI and insulin sensitivity were adjusted for, hypertensive boys (n = 21) had lower BMC (1435 v 1636 g; P = 0.03) than normotensive boys (n = 84); similarly, hypertensive girls (n = 25) had lower BMC (1438 v 1618 g; P = 0.02) than normotensive girls (n = 57). In postpubertal adolescents (Tanner stage 4-5; n = 48), inverse correlations were stronger (r = -0.40, P = 0.007); results were nonsignificant in prepubertal and pubertal children (Tanner stage 1-3; n = 139, P = 0.57). In postpubertal girls (n = 37), there were no significant correlations (P = 0.14); inverse correlations in postpubertal boys (n = 11) became markedly stronger (r = -0.80, P = 0.02).

CONCLUSION

Based on the study findings, SBP is inversely correlated with BMC in overweight adolescents; additionally, hypertensive subjects have lower adjusted means of BMC than normotensive subjects. These promising new findings suggest that hypertension may be a risk factor for osteopenia in overweight children and adolescents; this risk may be exacerbated in postpubertal boys.

Risk factors for diabetes mellitus type 2 and metabolic syndrome are comparable for previously growth hormone-treated young adults born small for gestational age (sga) and untreated short SGA controls

CONTEXT

Low birth weight might increase risk of diabetes mellitus type 2 and metabolic syndrome (MS). GH has insulin-antagonistic properties. Therefore, long-term follow-up of GH-treated children born small for gestational age (SGA) is important.

OBJECTIVE AND PATIENTS

The objective of the study was to evaluate insulin sensitivity (Si) and disposition index (DI), all components of the MS and IGF-I and IGF binding protein (IGFBP)-3 levels in 37 previously GH-treated young SGA adults in comparison with 25 untreated short SGA controls.

RESULTS

GH-treated subjects were 22.3 (1.7) yr old. Mean duration of GH treatment had been 7.3 (1.3) yr. Mean period after discontinuation was 6.5 (1.4) yr. Si and DI were comparable for GH-treated and untreated SGA subjects. Fasting glucose and insulin levels increased during GH treatment but recovered after discontinuation. Body mass index, waist circumference, high-density lipoprotein cholesterol levels, and triglycerides were equivalent. Systolic and diastolic blood pressure and cholesterol were significantly lower in GH-treated subjects. Thirty-two percent of untreated controls vs. none of the GH-treated subjects had an increased blood pressure. GH-induced rises in IGF-I and IGFBP-3 levels had completely recovered after GH stop.

CONCLUSION

At 6.5 yr after discontinuation of long-term GH treatment, Si, DI, fasting levels of glucose and insulin, body mass index, waist circumference, and IGF-I and IGFBP-3 levels were equivalent for GH-treated and untreated young SGA adults. Systolic and diastolic blood pressure and serum cholesterol were even lower in GH-treated subjects. These data are reassuring because they suggest that long-term GH treatment does not increase the risk for diabetes mellitus type 2 and MS in young adults.

Effect of growth hormone therapy on serum adiponectin and resistin levels in short, small-for-gestational-age children and associations with cardiovascular risk parameters

BACKGROUND

Adiponectin and resistin are fat cell-derived hormones, which are thought to be respectively protective and disadvantageous with regard to the development of cardiovascular disease and diabetes mellitus type 2. Low birth weight has been associated with increased risks for the development of these diseases. In short, small-for-gestational-age (SGA) children, GH therapy has several positive effects regarding cardiovascular risk factors. On the other hand, concern has been expressed about the effects of GH therapy on insulin sensitivity.

METHODS

We measured adiponectin and resistin levels in 136 short prepubertal children born SGA and their association with cardiovascular risk parameters and growth factors. Also, we compared the levels with normal-statured controls. The effect of GH treatment was evaluated in 50 short SGA children vs. baseline and vs. an untreated sex- and age-matched SGA control group.

RESULTS

Short SGA children had similar adiponectin and lower resistin levels, compared with normal-statured controls. In GH-treated SGA children, neither adiponectin nor resistin levels changed significantly during 2 yr of GH treatment. Compared with untreated sex- and age-matched SGA controls, GH-treated SGA children had similar adiponectin and lower resistin levels. Adiponectin correlated inversely with age but not any cardiovascular risk parameter or growth factor. Higher IGF-I levels in GH-treated children were associated with lower resistin levels.

CONCLUSIONS

Compared with normal-statured controls, short prepubertal SGA children had similar adiponectin and lower resistin levels. Two years of GH treatment had no effect on their adiponectin and resistin levels.

Insulin gene variable number of tandem repeats (INS VNTR) genotype and metabolic syndrome in childhood obesity

OBJECTIVE

The insulin variable number of tandem repeats (VNTR) polymorphism located in the insulin gene promoter (INS VNTR) has been associated with insulin levels in obese children. Hyperinsulinemia is a pivotal factor in the development of metabolic syndrome, an emerging complication in childhood obesity. With the present study, we aimed to test the associations between INS VNTR and the metabolic syndrome in juvenile-onset obesity.

SUBJECTS AND METHODS

We screened for the INS VNTR in 320 obese children (152 girls; mean age, 11.2 +/- 2.3 yr; mean z-score body mass index, 3.6 +/- 1.1). All of them underwent a standard oral glucose tolerance test; baseline measurements included blood pressure and plasma lipid and fasting insulin levels. By using the data derived from the oral glucose tolerance test, the whole-body insulin sensitivity and the insulinogenic index were calculated.

RESULTS

The prevalence of metabolic syndrome reached 39%. No differences in INS VNTR genotype distribution were observed between obese subjects and 200 lean, age- and sex-matched children (P = 0.7). Among obese subjects, the prevalence of the metabolic syndrome was significantly higher in subjects with the I/I genotype (P = 0.006); the risk for developing the metabolic syndrome was significantly higher in subjects carrying the I/I genotype (odds ratio, 2.5; 95% confidence interval, 1.5-3.9). Obese subjects homozygous for the class I allele showed higher insulin levels and insulinogenic index but lower whole-body insulin sensitivity.

CONCLUSIONS

We conclude that the I variant of the insulin promoter, when expressed in homozygotes, can predispose obese children to develop the metabolic syndrome.

Protein oxidation in obesity and insulin resistance

INTRODUCTION

Advanced oxidation protein products (AOPP) are considered reliable markers to estimate the degree of oxidant-mediated protein damage. Data on oxidative stress in childhood obesity and insulin resistance are limited.

OBJECTIVE

The aim of this study was to investigate the AOPP level as an oxidative stress marker in obesity and insulin resistance. The study included 57 pubertal obese children and adolescents (30 girls and 27 boys) and 20 healthy pubertal children and adolescents (11 girls and 9 boys).

MATERIALS AND METHODS

All participants in the obesity group underwent an oral glucose tolerance test (OGTT) and two separate groups were formed according to the existence of insulin resistance.

RESULTS

AOPP levels were measured in the obesity and control groups spectrophotometrically. The obesity group consisted of 25 children and adolescents with insulin resistance and 32 subjects without insulin resistance. AOPP levels in the obesity group were found to be significantly higher than those in the control group. Although AOPP levels in the subjects with insulin resistance were higher than the subjects without insulin resistance, there was no significant difference between AOPP levels of subgroups with insulin resistance and without insulin resistance.

CONCLUSION

This study showed protein oxidation in obesity with a novel oxidative stress marker and it also suggests that insulin resistance may play an important role as a source of oxidative stress in the development of other diseases after pubertal years.

Increased cerebral blood flow velocity in children with mild sleep-disordered breathing: a possible association with abnormal neuropsychological function

OBJECTIVE

Sleep-disordered breathing describes a spectrum of upper airway obstruction in sleep from simple primary snoring, estimated to affect 10% of preschool children, to the syndrome of obstructive sleep apnea. Emerging evidence has challenged previous assumptions that primary snoring is benign. A recent report identified reduced attention and higher levels of social problems and anxiety/depressive symptoms in snoring children compared with controls. Uncertainty persists regarding clinical thresholds for medical or surgical intervention in sleep-disordered breathing, underlining the need to better understand the pathophysiology of this condition. Adults with sleep-disordered breathing have an increased risk of cerebrovascular disease independent of atherosclerotic risk factors. There has been little focus on cerebrovascular function in children with sleep-disordered breathing, although this would seem an important line of investigation, because studies have identified abnormalities of the systemic vasculature. Raised cerebral blood flow velocities on transcranial Doppler, compatible with raised blood flow and/or vascular narrowing, are associated with neuropsychological deficits in children with sickle cell disease, a condition in which sleep-disordered breathing is common. We hypothesized that there would be cerebral blood flow velocity differences in sleep-disordered breathing children without sickle cell disease that might contribute to the association with neuropsychological deficits.

DESIGN

Thirty-one snoring children aged 3 to 7 years were recruited from adenotonsillectomy waiting lists, and 17 control children were identified through a local Sunday school or as siblings of cases. Children with craniofacial abnormalities, neuromuscular disorders, moderate or severe learning disabilities, chronic respiratory/cardiac conditions, or allergic rhinitis were excluded. Severity of sleep-disordered breathing in snoring children was categorized by attended polysomnography. Weight, height, and head circumference were measured in all of the children. BMI and occipitofrontal circumference z scores were computed. Resting systolic and diastolic blood pressure were obtained. Both sleep-disordered breathing children and the age- and BMI-similar controls were assessed using the Behavior Rating Inventory of Executive Function (BRIEF), Neuropsychological Test Battery for Children (NEPSY) visual attention and visuomotor integration, and IQ assessment (Wechsler Preschool and Primary Scale of Intelligence Version III). Transcranial Doppler was performed using a TL2-64b 2-MHz pulsed Doppler device between 2 pm and 7 pm in all of the patients and the majority of controls while awake. Time-averaged mean of the maximal cerebral blood flow velocities was measured in the left and right middle cerebral artery and the higher used for analysis.

RESULTS

Twenty-one snoring children had an apnea/hypopnea index <5, consistent with mild sleep-disordered breathing below the conventional threshold for surgical intervention. Compared with 17 nonsnoring controls, these children had significantly raised middle cerebral artery blood flow velocities. There was no correlation between cerebral blood flow velocities and BMI or systolic or diastolic blood pressure indices. Exploratory analyses did not reveal any significant associations with apnea/hypopnea index, apnea index, hypopnea index, mean pulse oxygen saturation, lowest pulse oxygen saturation, accumulated time at pulse oxygen saturation <90%, or respiratory arousals when examined in separate bivariate correlations or in aggregate when entered simultaneously. Similarly, there was no significant association between cerebral blood flow velocities and parental estimation of child's exposure to sleep-disordered breathing. However, it is important to note that whereas the sleep-disordered breathing group did not exhibit significant hypoxia at the time of study, it was unclear to what extent this may have been a feature of their sleep-disordered breathing in the past. IQ measures were in the average range and comparable between groups. Measures of processing speed and visual attention were significantly lower in sleep-disordered breathing children compared with controls, although within the average range. There were similar group differences in parental-reported executive function behavior. Although there were no direct correlations, adjusting for cerebral blood flow velocities eliminated significant group differences between processing speed and visual attention and decreased the significance of differences in Behavior Rating Inventory of Executive Function scores, suggesting that cerebral hemodynamic factors contribute to the relationship between mild sleep-disordered breathing and these outcome measures.

CONCLUSIONS

Cerebral blood flow velocities measured by noninvasive transcranial Doppler provide evidence for increased cerebral blood flow and/or vascular narrowing in childhood sleep-disordered breathing; the relationship with neuropsychological deficits requires further exploration. A number of physiologic changes might alter cerebral blood flow and/or vessel diameter and, therefore, affect cerebral blood flow velocities. We were able to explore potential confounding influences of obesity and hypertension, neither of which explained our findings. Second, although cerebral blood flow velocities increase with increasing partial pressure of carbon dioxide and hypoxia, it is unlikely that the observed differences could be accounted for by arterial blood gas tensions, because all of the children in the study were healthy, with no cardiorespiratory disease, other than sleep-disordered breathing in the snoring group. Although arterial partial pressure of oxygen and partial pressure of carbon dioxide were not monitored during cerebral blood flow velocity measurement, assessment was undertaken during the afternoon/early evening when the child was awake, and all of the sleep-disordered breathing children had normal resting oxyhemoglobin saturation at the outset of their subsequent sleep studies that day. Finally, there is an inverse linear relationship between cerebral blood flow and hematocrit in adults, and it is known that iron-deficient erythropoiesis is associated with chronic infection, such as recurrent tonsillitis, a clinical feature of many of the snoring children in the study. Preoperative full blood counts were not performed routinely in these children, and, therefore, it was not possible to exclude anemia as a cause of increased cerebral blood flow velocity in the sleep-disordered breathing group. However, hemoglobin levels were obtained in 4 children, 2 of whom had borderline low levels (10.9 and 10.2 g/dL). Although there was no apparent relationship with cerebral blood flow velocity in these children (cerebral blood flow velocity values of 131 and 130 cm/second compared with 130 and 137 cm/second in the 2 children with normal hemoglobin levels), this requires verification. It is of particular interest that our data suggest a relationship among snoring, increased cerebral blood flow velocities and indices of cognition (processing speed and visual attention) and perhaps behavioral (Behavior Rating Inventory of Executive Function) function. This finding is preliminary: a causal relationship is not established, and the physiologic mechanisms underlying such a relationship are not clear. Prospective studies that quantify cumulative exposure to the physiologic consequences of sleep-disordered breathing, such as hypoxia, would be informative.

Arterial wall thickening and stiffening in children and adolescents with type 1 diabetes

OBJECTIVE

We evaluated structural and functional characteristics of the common carotid artery (CCA), a marker of early carotid atherosclerosis, and investigated their relation to metabolic and anthropometric parameters in children and adolescents with type 1 diabetes.

MATERIALS AND METHODS

Non-invasive ultrasonographic measurements were made in 45 type 1 diabetic patients and 33 controls. Age, sex, and body mass index were matched between patients and controls. We investigated intima-media thickness (IMT), compliance, distensibility, diastolic wall stress (DWS) and incremental elastic modulus (IEM) of the CCA. Metabolic and anthropometric parameters such as serum lipids, plasma glycated haemoglobin, body mass index, waist-hip ratio and blood pressure were assessed.

RESULTS

The diabetic patients had significantly higher CCA-IMT than the controls (0.48+/-0.06mm versus 0.33+/-0.07mm; p<0.001). The diabetic children had significantly higher values than the controls for DWS (1.18+/-0.29mmHgx10(2) versus 0.81+/-0.25mmHgx10(2); p<0.001) and for IEM (1.26+/-0.57mmHgx10(3) versus 0.77+/-0.28mmHgx10(3); p<0.001). The difference was not significant between patients and controls for arterial compliance and for distensibility (p>0.05). In a multivariate regression model for all subjects, diabetic state was the best predictor of IMT (p<0.001), DWS (p<0.001) and IEM (p=0.001).

CONCLUSION

Our results suggested that children and adolescent patients with type 1 diabetes are associated with early impairment of CCA structure and function and that diabetic state may be the main risk factor for CCA wall stiffening and thickening, which are of considerable concern as possible early events in the genesis of atheroma.

Changes of cardiovascular risk factors in obese children effects of inpatient and outpatient interventions

OBJECTIVE

The aim of the study was to compare the benefits of 2 different therapeutic approaches on cardiovascular risk factors (CVRF) in obese children and adolescents.

METHODS

We analyzed the changes of weight status (as standard deviation score-body mass index [SDS-BMI]), blood pressure, lipids, and insulin levels in obese children (age range, 10-14 years) during a 1-year outpatient intervention based on lifestyle changes (group A, n = 124) and during a 6-week inpatient intervention program with dietary restriction and exercise therapy (group B, n = 119). In addition, we studied these parameters in 65 obese children without intervention for 1 year (control group).

RESULTS

Age, degree of overweight, sex, and CVRF did not differ significantly between the control group and the intervention groups at baseline. During the observation period, CVRF did not change in the control group, whereas SDS-BMI slightly increased (+0.1 SDS-BMI). The SDS-BMI decreased significantly (P < 0.001) in group A (SDS-BMI, -0.40) and comparably in group B (SDS-BMI, -0.43). The decreases of total (P < 0.001) and low-density lipoprotein-cholesterol levels (P = 0.049) were significantly greater in group B, whereas triglyceride (P = 0.040) and insulin (P = 0.006) levels decreased significantly and were more pronounced in group A. High-density lipoprotein-cholesterol level increased significantly (P < 0.001) only in group A. Blood pressure decreased significantly (P < 0.01) and comparably in both intervention groups (A and B).

CONCLUSIONS

In contrast to obese children without intervention, CVRF improved in obese children with intervention. The 6-week inpatient intervention led to a significant greater decrease of total and low-density lipoprotein-cholesterol levels as compared with the 1-year outpatient intervention, although the outpatient intervention yielded a significantly greater improvement in insulin, triglycerides, and high-density lipoprotein-cholesterol levels.

Long-term follow-up of cardiovascular disease risk factors in children after an obesity intervention

BACKGROUND

Data concerning the long-term improvement of cardiovascular disease (CVD) risk factors after an obesity intervention in children are limited.

OBJECTIVE

We studied changes in weight status and CVD risk factors in children in an intervention program and evaluated whether these changes were sustained 1 y after the end of the intervention.

DESIGN

We analyzed changes in the SD score (SDS) of body mass index [BMI; in kg/m2 (SDS-BMI)], blood pressure (BP), lipids, and homeostasis model assessment index of insulin resistance (HOMA-IR) over the course of 2 y in 240 obese (BMI > 97th percentile) children aged 6-14 y (x age: 10.4 y; x BMI: 26.9). Of these 240 children, 203 participated in a 1-y intervention program of physical exercise, nutrition education, and behavior therapy. We compared these children with 37 obese children who underwent no intervention and with 12 normal-weight children of the same age and sex.

RESULTS

Obese children had significantly (P < 0.05) higher BP, HOMA-IR, and insulin, triacylglycerol, and LDL-cholesterol concentrations and lower HDL-cholesterol concentrations than did normal-weight children. Twenty-nine children dropped out of the intervention. Only in the 126 children who reduced their SDS-BMI did BP (8% and 12% decreases in systolic and diastolic BP, respectively), lipids (12% and 5% decreases in triacylglycerol and LDL cholesterol, respectively; 7% increase in HDL cholesterol), insulin (13% decrease), and HOMA-IR (17% decrease) improve significantly (P < 0.05). Reduction in SDS-BMI and all benefits regarding CVD risk factors were sustained 1 y after the end of the intervention in the children whose SDS-BMI decreased.

CONCLUSIONS

Long-term multidisciplinary intervention led to a reduction in SDS-BMI in most of the obese children 1 y after the end of the intervention. Reduction in SDS-BMI was accompanied by an improvement in CVD risk factors.

Metabolic syndrome in Turkish children and adolescents

The aim of this study was to determine the prevalence and phenotype of metabolic syndrome in Turkish children and adolescents. We adapted the National Cholesterol Education Program Adult Treatment Panel III criteria of metabolic syndrome to children and adolescents. Using the international cutoff points and percentiles, we determined 10- to 17-year-old Turkish children and adolescents with high blood pressure, high triglyceride (TG), low high-density lipoprotein cholesterol (HDL-C), fasting glucose of 100 mg/dL or greater, and elevated body mass index corresponding to overweight or obesity. We examined 1385 apparently healthy students between the ages of 10 to 17 years from Ankara, Turkey: 4.9% of the subjects were overweight or obese; 29.2% had either low HDL-C and/or high TG levels; and 15.7% had either systolic or diastolic blood pressure above the 95th age-, sex-, and height-specific percentile. Thirty students (2.2%) had metabolic syndrome by having 3 or more risk variables. Metabolic syndrome was nearly 10 times more common among overweight and obese students (21%), compared with lean students. Components of metabolic syndrome such as high blood pressure and high TG, and low HDL-C levels were common among Turkish children and adolescents. Strategies should focus on early detection and treatment of these risk variables in Turkish children.

Beta-cell autoantibodies in children with type 2 diabetes mellitus: subgroup or misclassification?

BACKGROUND

In adults, a fraction of diabetic individuals with beta-cell autoantibodies has initially non-insulin requiring diabetes clinically appearing as type 2 diabetes mellitus (T2DM), named latent autoimmune diabetes in adulthood (LADA). The occurrence of beta-cell autoantibodies in European children and adolescents with T2DM has not been reported so far.

METHODS

The frequency of beta-cell autoantibodies (anti-GAD, anti-IA-2, and anti-ICA) was determined in 7050 diabetic children and adolescents. The type of diabetes was classified by paediatric diabetic specialists based on the clinical presentation. Children with non-insulin dependent T2DM over a one year period were studied separately.

RESULTS

A total of 6922 children were clinically classified as having type 1 diabetes (T1DM) and 128 children as having T2DM. Thirty six per cent of the children with T2DM had at least one detectable beta-cell autoantibody. These children did not differ significantly from the children with T2DM and without autoantibodies in respect of age, gender, weight status, lipids, blood pressure, C-peptide, glucose, and HbA1c at manifestation, as well as frequency of anti-thyroidal antibodies and insulin treatment during follow up. In the subgroup of the 38 children with T2DM without insulin requirement over a one year period, autoantibodies occurred in 32%. These 12 children were predominantly obese (67%), female (67%), and in the pubertal age range.

CONCLUSION

beta-cell autoantibodies were detectable in a subgroup of initially non-insulin dependent diabetic children and adolescents with the clinical appearance of T2DM. Following the terminology "latent autoimmune diabetes in adulthood (LADA)", this subgroup might be classified as "LADY" (latent autoimmune diabetes in youth).

High prevalence of renal dysfunction in long-term survivors after pediatric liver transplantation

OBJECTIVE

To determine the prevalence and identify variables associated with renal dysfunction in long-term survivors of pediatric liver transplantation.

STUDY DESIGN

Data from 117 patients who survived>or=3 years after liver transplantation were analyzed. Demographic and clinical information was obtained from chart review and from a clinical care database. The dependent variable was renal function as determined by measured glomerular filtration rate (mGFR). Univariate and multivariate analyses were performed to identify independent variables associated with renal dysfunction (mGFR<70 mL/min per 1.73 m2).

RESULTS

The average time since liver transplant was 7.6+/-3.4 years (range, 3 to 14.6 years). When the last available mGFR for all patients was analyzed, renal dysfunction was present in 32%. In the univariate analysis, mGFR at 1 year after transplant, cyclosporine immunosuppression, and time since transplant were significant; the second two were strongly collinear. Using multiple logistic regression modeling excluding time since transplant, cyclosporine and mGFR at 1 year after transplant were strongly associated with renal dysfunction.

CONCLUSIONS

Renal dysfunction is a common complication in children who survive liver transplantation. Our observations are of critical importance because children may live long enough to move from a stage of renal insufficiency characterized by asymptomatic decreased GFR to symptomatic end-stage renal disease.

Type 2 diabetes in children and adolescents--the next epidemic?

OBJECTIVE

To provide an overview of the incidence of type 2 diabetes in children and adolescents and provide direction for clinicians who care for children and adolescents.

RESEARCH DESIGN AND METHOD

The data presented in this review were obtained from published literature and abstracts presented at scientific meetings. Clinical trials and review articles were identified using the search terms 'metabolic syndrome', 'type 2 diabetes mellitus', 'children', and 'adolescents' in a MEDLINE search from 1995-2005. Additionally, the bibliographies of the identified articles were reviewed.

RESULTS

Type 2 diabetes is rising rapidly in children and adolescents worldwide. Changing a child's living environment to include physical activity, and a well balanced, low fat, high fiber diet, are important for the maintenance of a desirable body weight and improving insulin sensitivity. Maintaining euglycemia with metformin, sulfonylureas, thiazolinediones, and insulin is recommended. Effective treatment of co-morbid problems such as hypertension and dyslipidemia can decrease the risk of cardiovascular complications.

CONCLUSIONS

The prevalence of type 2 diabetes in children will continue to rise until effective measures are taken to prevent obesity in this age group. Ensuring that children have a well-balanced low fat, high fiber, diet, combined with physical activity, will promote weight loss or maintenance, improve insulin sensitivity, and decrease the risk of diabetes and cardiovascular disease. Pharmacologic therapy is recommended for children who are unable to achieve satisfactory glycemic control through physical activity and diet.

The fate of systemic blood pressure in patients after effectively stented coarctation

AIMS

The current study was designed to assess midterm results of stent implantation into the aorta for native and recurrent coarctation (CoA) in children and young adults.

METHODS AND RESULTS

Forty-three patients (native CoA, 8; female, 12) were treated with stent implantation at a median age of 16.8 years (range 7.9-44.8 years). Only stents dilatable to an adult size aorta were implanted. All but two patients with functionally univentricular hearts had arterial hypertension. Exercise tests, 24-h blood pressure, clinical examination, echocardiography, and elective catheterization were used to assess follow-up. The narrowed segment was widened significantly from a median of 8 to 12.4 mm (P < 0.0005). The peak-to-peak gradient between the ascending and the descending aorta was lowered significantly from a median of 22 mmHg to 1 mmHg (P < 0.0005). No major complications occurred. The systolic blood pressure at the right arm was lowered significantly (P < 0.0005) from 144 mmHg before stent implantation to 128 mmHg at the last visit. At a median follow-up of 30 months (3-72 months), 68% of all patients were classified to be normotensive.

CONCLUSION

Stent implantation for selected patients with recurrent and native CoA is safe and may effectively reduce the blood pressure gradient across the CoA site. We suggest using only stents dilatable to an adult size aorta. However, arterial hypertension persists in a significant number of the patients. Impaired elastic properties of the aorta may be the cause for this finding.

Intima media thickness in childhood obesity: relations to inflammatory marker, glucose metabolism, and blood pressure

Obesity in childhood is discussed to be associated with hypertension, dyslipidemia, impaired glucose metabolism, and chronic inflammation. It has not yet been studied in obese children which of these cardiovascular risk factors are related to intima media thickness (IMT), a noninvasive marker for early atherosclerotic changes. We collected the clinical data (age, sex, pubertal stage, percentage of body fat, SD score of body mass index [SDS-BMI]) and measured systolic blood pressure [SBP] and diastolic blood pressure [DBP], triglycerides [TGs], high- and low-density lipoprotein cholesterol, glucose, insulin, and high-sensitivity C-reactive protein [hsCRP]) in 96 obese children (median age, 11 years). The control group was composed of 25 nonobese children of the same age, sex, and pubertal stage. We determined the carotid IMT of all the patients by B-mode ultrasound with a 14-MHz linear transducer. Obese children demonstrated a significantly (P < .001) thicker intima media (median, 0.6 mm) as compared with the control group (median IMT, 0.4 mm). IMT was significantly correlated to the SDS-BMI (r = 0.38, P < .001), percentage of body fat (r = 0.39, P < .001), SBP (r = 0.39, P < .001) and DBP (r = 0.29, P = .002), glucose (r = 0.30, P = .001), and hsCRP levels (r = 0.29, P = .002). In stepwise backward multiple linear regression analysis, IMT correlated significantly to BMI (r2 = 0.05, P = .044), SBP (r2 = 0.15, P = .013), glucose (r2 = 0.05, P = .028), and hsCRP (r2 = 0.07, P = .005). Because IMT is increased in obese children, vascular changes in obesity seem to occur already in childhood. These changes are related to the cardiovascular risk factors of obesity, especially hypertension, chronic inflammation, and impaired glucose metabolism.

High-sensitive C-reactive protein, tumor necrosis factor alpha, and cardiovascular risk factors before and after weight loss in obese children

To confirm the existence of obesity-induced inflammation and to clarify the association between such inflammation and other cardiovascular risk factors, we investigated the relationships between high-sensitive C-reactive protein (hsCRP), tumor necrosis factor alpha (TNF-alpha), obesity, blood pressure, lipids, and insulin resistance in a long-term follow-up of obese children. We compared the serum concentrations of hsCRP, TNF-alpha, high-density lipoprotein cholesterol, and triglycerides as well as blood pressure and the insulin resistance index (homeostasis model assessment [HOMA]) of 14 nonobese and 31 obese children. Furthermore, we studied the changes in these parameters in 16 obese children who lost weight and in 15 obese children without weight change over a 1-year period. In the obese children, blood pressure (P=.003), HOMA (P=.034), and triglyceride (P=.011), TNF-alpha (P=.015), and hsCRP (P<.001) levels were significantly higher, whereas high-density lipoprotein cholesterol concentrations were significantly (P=.015) lower compared with the nonobese children. Weight loss was associated with a significant decrease in hsCRP (P=.008) and triglyceride (P=.048) levels, HOMA (P<.001), and blood pressure (P=.019), whereas there were no significant changes in the children with stable weight status. The changes in hsCRP and TNF-alpha levels over the 1-year period were not significantly correlated to the changes in lipids, blood pressure, and HOMA. Obese children demonstrated significantly higher levels of hsCRP and TNF-alpha compared with nonobese children. The chronic inflammation markers TNF-alpha and hsCRP were independent of lipids, blood pressure, and insulin resistance index. Weight loss was associated with the significant decrease of hsCRP and triglyceride levels, and blood pressure.

Short- and long-term cardiovascular effects of mixed amphetamine salts extended release in children

OBJECTIVE

To assess the short- and long-term cardiovascular effects of once-daily treatment with a mixed amphetamine salts extended-release formulation (MAS XR; Adderall XR(R)) in children age 6 to 12 years with attention-deficit/hyperactivity disorder (ADHD).

STUDY DESIGN

Short-term cardiovascular effects were assessed during a 4-week, double-blind, randomized, placebo-controlled, forced-dose-titration study of once-daily 10, 20, and 30 mg MAS XR (n = 580). Long-term cardiovascular effects were assessed in 568 subjects during a 2-year, open-label extension study of MAS XR (10 to 30 mg/day). Resting sitting blood pressure and pulse were measured at baseline and weekly during the short-term study, then monthly during long-term treatment.

RESULTS

Changes in blood pressure, pulse, and QT interval corrected by Bazett's formula (QTcB) in children receiving MAS XR were not statistically significantly different than those changes seen in children receiving placebo during short-term treatment. Mean increases in blood pressure after 2 years of MAS XR treatment (systolic, 3.5 mm Hg; diastolic, 2.6 mm Hg) and pulse (3.4 bpm) were clinically insignificant, and there was no apparent dose-response relationship.

CONCLUSIONS

Cardiovascular effects of short- and long-term MAS XR were minimal during short- and long-term MAS XR treatment at doses of </= 30 mg/day in otherwise healthy children.

Use of low-dose rocuronium for intubation of children during volunteer surgery abroad

BACKGROUND

Low-dose rocuronium (ROC) might improve safety during volunteer surgery abroad (VSA) by facilitating intubation with a lower halothane concentration than is typically used. We hypothesized that 0.25 mg.kg(-1) of ROC would improve intubation conditions during 3% halothane induction and still allow for rapid return to spontaneous ventilation (SV).

METHODS

During Operation Smile's 2002 mission to Honduras, patients aged 3 months-11 years were randomized to receive ROC 0.25 mg.kg(-1) (n = 19), or placebo (n = 23). Induction was with 3% halothane in 100% O(2), with ventilation assisted and controlled when possible, and normocarbia maintained. An i.v. was placed after induction, and ROC or placebo given. Direct laryngoscopy (DL) was performed 3 min later by a blinded laryngoscopist who assessed conditions according to predetermined criteria.

RESULTS

Adequate intubation conditions occurred in 89 and 87% of patients (P = 0.59), and mean times from DL until the return to SV were 9.8 and 4.3 min (P = 0.003), in the ROC and placebo groups, respectively. For the placebo group, the presence of SV at DL was predictive of inadequate intubation conditions (P = 0.006).

CONCLUSIONS

When administering 3% halothane for induction of VSA patients, a high frequency of adequate intubation conditions can be achieved without a relaxant, rendering the known benefits of 0.25 mg.kg(-1) of ROC unapparent. ROC 0.25 mg.kg(-1) does allow rapid return to SV.

Trajectory of systolic blood pressure in children and adolescents

PURPOSE

Rapid height and weight changes during childhood contribute markedly to blood-pressure change during children's physical growth. This article evaluates the differences in systolic blood pressure (SBP) growth or changes between four gender-ethnic groups: African American males (AM), Caucasian males (CM), African American females (AF), and Caucasian females (CF).

METHODS

Subjects 6-9 years old at entry (n = 1302) were followed for 12 years. The repeated-measure data of SBP were analyzed using the Gompertz growth model with random coefficients.

RESULTS

Mean SBP (mmHg) at age 6 years was lowest in African American girls (82.23 +/- 0.76) and highest in Caucasian boys (102.83 +/- 0.5). And for both ethnic groups, girls had lower levels at which SBP growth stopped. The peak growth ages (years) also differed by group: 9.30 +/- 0.73, 9.91 +/- 0.28, 10.00 +/- 0.82, and 10.60 +/- 0.22 for African American girls, African American boys, Caucasian girls and Caucasian boys, respectively.

CONCLUSION

SBP growth differed among gender-ethnic groups with respect to mean SBP level at age 6, the level at which SBP growth stops and the mean age at which SBP growth rate was at its peak.

Results of blood pressure screening in a population of school-aged children in the province of Milan: role of overweight

OBJECTIVES

To study the prevalence of high blood pressure (BP) in an Italian paediatric population, and to verify whether in this population elevated BP values are associated with overweight (OW).

STUDY DESIGN

Children (1206 males, 1210 females) from the lower-grade public schools (ages 6-11 years) were studied. Body weight, height and BP were measured in each child. Elevated BP was defined if resting systolic and/or diastolic BP values equalled or exceeded the 95th percentile according to gender, age and height, based on the US normative BP tables. Overweight children were identified using four different methods: (1) the classification based on the relative body weight; (2) the French references by Rolland-Cachera et al. (Am J Clin Nutr 1982; 36:178-184); (3) the International Obesity Task Force charts; and (4) the Italian charts defined by Cacciari et al. (Eur J Clin Nutr 2002; 56:171-180).

RESULTS

The prevalence of high BP in our population was 4.2% and was significantly higher in females (65/1210 = 5.4%) than in males (37/1206 = 3.1%), P = 0.005. The different methods used to define OW provide different estimates of OW prevalence (from 17.0 to 38.6%). The percentage of high BP subjects was significantly higher in OW than in normal-weight children regardless of the method used for the definition of the weight class (P < 0.0001), in both genders. In addition, for each age range, absolute systolic and diastolic BP values were higher in OW as compared to normal-weight children both in males and in females (P < 0.0001).

CONCLUSIONS

Our study indicates the importance of performing BP screenings in the paediatric population, and to promote interventions that may reduce the prevalence of OW in children.

Cardiovascular risk factors in overweight German children and adolescents: relation to gender, age and degree of overweight

OBJECTIVE

So far in Europe, no large studies have been published on the frequencies of the cardiovascular risk factors hypertension and dyslipidaemia in overweight children.

METHODS

Diagnosis of hypertension, decreased HDL-cholesterol, increased triglycerides, total and LDL-cholesterol were documented for 1004 overweight children and adolescents (aged 4-8 years, 52% girls, BMI-SDS in median 2.43) referred to four obesity centres. Hypertension and dyslipidaemia were defined by cut off points above the 95th percentile of healthy children. Multivariate linear regression was conducted for the dependent variables systolic and diastolic blood pressure, triglycerides, HDL-, LDL-, and total cholesterol, including gender, degree of overweight (SDS-BMI) and age as independent variables.

RESULTS

Thirty-seven percent of the children studied suffered from hypertension, 27% displayed increased total cholesterol, 26% increased LDL-cholesterol, 20% increased triglycerides and 18% decreased HDL-cholesterol. Seventy percent of all children had at least one unfavourable cardiovascular risk factor. Hypertension and dyslipidaemia were observed in any age group and in any degree of overweight at least twofold above the suspected rate of 5%. SDS-BMI was significantly related to blood pressure (systolic: coefficient 7.26, p < 0.001, diastolic: coefficient 3.21, p < 0.001), weakly to triglycerides (coefficient 0.12, p = 0.007), slightly negatively to HDL-cholesterol (coefficient -0.06, p = 0.001) and not related to total and LDL-cholesterol. Age was positively related to blood pressure (systolic: coefficient 2.436, p < 0.001, diastolic: coefficient 0.54, p < 0.001) and negatively to HDL cholesterol (coefficient -0.02, p < 0.001).

CONCLUSION

Cardiovascular risk factors were frequently present in a large collective of overweight European children and adolescents. They occurred mostly independently of age, gender and degree of overweight. Therefore, screening for cardiovascular risk factors seems meaningful at any age and degree of overweight in childhood.

Adolescence as possible critical temporal window for blood pressure short term monitoring in boys and girls

Adolescence is a critical temporal window for the development of obesity in adult age. We studied this period for short-term monitoring of blood pressure in both genders. Weight, height, body mass index (BMI), systolic and diastolic blood pressure (SBP, DBP) were recorded in 937 adolescents, 474 boys and 463 girls aged 12 years, and again 2 years later in the same subjects. Boys with BP values > or = 95th percentile at both ages (no. = 8) showed at 12 years weight (kg 61.4) height (cm 159.5) and BMI (23.5), and also at 14 years (77.0, 172.4, 25.6) values consistently higher than boys with high BP values at either ages taken singularly (no. = 32 + 32) (mean 49.2, 154.4, 21.5, respectively, at 12 years, and 62.1, 167.0, 22.2 at 14 years). These 64 boys, had values higher than boys with BP always below the 95th percentile (no. = 402) (45.5, 151.4, 19.7 at 12 years, and 56.9, 164.6, 20.9 at 14 years). This was confirmed for weight and BMI in girls. Stepwise logistic regression revealed that weight at 12 years and high BP values at 12 years were predictive independent risk factors for hypertension at 14 years. Odds ratio indicated that increment of body weight unit (1 kg) at 12 years predicted an average increase of 4% of risk for high BP values at 14 years, while high BP values at 12 years was predictive for a 2.19 times risk for high BP values at 14 years. Body weight, BMI and BP at 12 years of age may give useful indications for the prevision (and possible prevention) of hypertension and overweight at 14 years of age.

Early menarche and the development of cardiovascular disease risk factors in adolescent girls: the Fels Longitudinal Study

The purpose of this study was to evaluate the influence of menarcheal age on changes in insulin, glucose, lipids, and blood pressure during adolescence and to assess whether body composition modifies this relationship. We examined 391 girls, a subset of Fels Longitudinal Study female participants (8-21 yr of age). Self-reported menarcheal age was classified based on the National Health and Nutrition Examination Survey III distribution, in which early menarche was at the 25th percentile or less (11.9 yr). Age at menarche was examined in relation to measures of body composition [e.g. fat-free mass (FFM) and percent body fat (PBF)], insulin resistance, blood pressure, and lipid profile. The effects of menarcheal age and body composition on cardiovascular disease risk factor changes were analyzed with serial data mixed models. Median menarcheal age was 12.7 yr (range, 9.8-17.0 yr), with 91 girls (23%) classified as early menarche. Girls with early menarche had more deleterious changes in insulin, glucose, blood pressure, FFM, and PBF levels than girls with average or late menarche. Menarcheal age adversely affected cardiovascular disease risk factor changes independent of age and changes in FFM or PBF. Girls with early menarche exhibited elevated blood pressure and glucose intolerance compared with later maturing girls, independent of body composition.

Renal impairment and hypertension in brain tumor patients treated in childhood are mainly associated with cisplatin treatment

BACKGROUND

This study was designed to evaluate the renal consequences of the treatment of brain tumor patients diagnosed in childhood.

PROCEDURE

One hundred four primary brain tumor patients diagnosed before 17 years of age from 1983 to 1997 had been treated in Tampere University Hospital, Finland. Of the 80 survivors 52 (65.0%) were examined at a median age of 14.4 years (range 3.8-28.7) and median 6.0 years (range 1.2-14.8) after the last treatment. The main outcome measures were blood pressure (BP), renal function, and calcium metabolism.

RESULTS

Eight patients (15.4%) were hypertensive. Elevated BP was observed especially after exposure both to cisplatin and cranial irradiation. Spinal radiation did not increase the risk of elevated BP. Other adverse effects were observed only in patients treated with cisplatin. Five out of 14 patients treated with cisplatin evinced renal glomerular dysfunction (GFR < 87 mL/min/1.73 m2) immediately after treatment. They had a high cumulative dose of cisplatin (490-880 mg/m2). Recovery from renal glomerular dysfunction was observed in one patient. Nine of 14 patients were hypomagnesemic at the close of cisplatin treatment. Thereafter the magnesium level decreased in 10/14 cases (P = 0.006). During the study 10/14 were hypomagnesemic (P < 0.001); one evinced severe symptomatic hypomagnesemia. Low plasma phosphate (P = 0.016) and potassium levels (P = 0.026), tubular proteinuria (P = 0.055), metabolic alkalosis (P = 0.071), and hyperuricemia (P = 0.114) were also more common in patients on cisplatin treatment.

CONCLUSIONS

Elevated BP is common among brain tumor patients treated in childhood. After cisplatin treatment renal glomerular dysfunction appears mostly to be permanent. Persistent and even progressive changes in renal tubular function are seen.

PEDIATRIC UROLOGICAL CAUSES OF HYPERTENSION

PURPOSE

We reviewed the association of hypertension with several common pediatric urological conditions.

MATERIALS AND METHODS

We comprehensively reviewed the published literature linking hypertension with urinary tract infection, renal scarring, vesicoureteral reflux, multicystic dysplastic kidney, ureteropelvic junction obstruction and posterior urethral valves.

RESULTS

Hypertension is a recognized sequela of several common pediatric urological conditions. It is thought to be a direct consequence of renal damage or scarring often resulting from vesicoureteral reflux and/or febrile urinary tract infection. Multicystic dysplastic kidney has rarely been shown to cause hypertension when examined in large series rather than as isolated case reports. Ureteropelvic junction obstruction and posterior urethral valves have been linked to hypertension, although to our knowledge no series to date has specifically examined this relationship and smaller retrospective reviews seldom describe associated hypertension.

CONCLUSIONS

Several pediatric urological conditions are known to cause hypertension. However, methodological flaws in the literature, including a lack of standardized blood pressure followup, highly variable patient populations and poor control of concomitant urological abnormalities, greatly limit the ability to establish a causative link between any 1 specific condition and hypertension. Early diagnosis, the prevention of infection, close clinical followup and early intervention remain the primary means of preventing pediatric urological causes of hypertension.

Recognition and management of autonomic dysreflexia in pediatric spinal cord injury

BACKGROUND

Autonomic dysreflexia (AD) is a well-documented complication of spinal cord injury (SCI) at or above the T6 level. However, research into AD has focused primarily on the adult. Because research that involves children with SCI is scarce, current guidelines may not be appropriate for children. Therefore, many episodes of AD may be unrecognized or inappropriately treated. To address this issue, Shriners Hospitals for Children undertook the development of a protocol specific to children and adolescents.

METHOD

A task force was developed to look at current literature on AD and blood pressure in children. Utilizing this literature and consensus among the task force members, the tools necessary to treat children with SCI at risk for AD were developed.

RESULTS

The task force developed several products intended to assist in the recognition and management of AD. These include an event flow sheet for recording incidents of AD, a letter for the child's school or primary care physician that provides a brief summary of AD and the child's baseline blood pressure, and a policy/protocol with 2 age-specific algorithms to standardize interventions across the 3 Shriners Hospitals in the United States with SCI programs (California, Illinois, and Pennsylvania).

CONCLUSION

The Shriners Hospitals for Children Task Force on Autonomic Dysreflexia in Children with Spinal Cord Injury has developed several tools specific to children. However, many questions remain to be answered concerning blood pressure norms and the clinical presentation of AD in children.

Strategies for prevention and management of hypertension throughout life

Hypertension has been acknowledged as one of the greatest and established risk factors for cardiovascular diseases. In this special article, strategies for the prevention and management of hypertension throughout human’s life were discussed. Studies showing the relationship of birth weight and height increase in childhood to future blood pressure suggest that both environments during pregnancy and during childhood and adolescence are important to prevent hypertension. The promotion of a DASH (Dietary Approach to Stop Hypertension) dietary pattern, rich in fruits and vegetables, is important not only for treatment of high blood pressure but also for long-term prevention of blood pressure rise as well. Blood pressure measured in young adulthood can effectively predict long-term risks of cardiovascular and all-cause mortality, so population-wide primary prevention of high blood pressure for young adults is important. Recent large scale cohort studies confirmed that detection and evaluation of hypertension based mainly on systolic blood pressure remains the most practical and easy approach in the general population for young adult, middle-aged, and older men and women. Researchers in Asia are desired to establish high-quality epidemiologic evidences for Asian for the prevention and management of hypertension.

Hypopnea in pediatric patients with obesity hypertension

Obesity is associated with the development of hypertension but it is still not clear why hypertension is not observed in all obese patients. Obesity is a risk factor for the development of obstructive sleep apnea syndrome (OSAS) in children. OSAS has been linked to the development of hypertension in adults and children. The purpose of this study was to test the hypothesis that OSAS is one of the reasons that some obese children are hypertensive and some are not. The overnight polysomnography records of 90 patients (aged 4.2-18.8 years) were reviewed. BMI(score) [body mass index (BMI)/95th percentile BMI for age, sex, and race] was used to express the degree of obesity. The severity of systolic hypertension and diastolic hypertension were expressed as SBP(score) (systolic BP/the 95th percentile systolic BP for age, sex, and height) and DBP(score) (diastolic BP/the 95th percentile diastolic BP for age, sex, and height), respectively. OSAS was defined as more than one episodes of apnea per hour (AI) or an O(2) saturation associated with obstructive apnea of less than 90%. There were 56 obese patients; 42 were hypertensive and 40 patients were diagnosed with OSAS. The incidence of hypertension (68% vs. 30%) and obesity (75% vs. 52%) was higher in OSAS patients than those without OSAS. Compared with the non-obese patients, obese patients had a higher incidence of hypertension or OSAS, a higher BMI(score), SBP(score), DBP(score), AI, hypopnea index (HI), and apnea-hypopnea index (AHI). In obese patients, both SBP(score) and DBP(score) correlated positively with BMI(score), arousal index, and HI. DBP(score) also correlated positively with AHI. Multiple regression analysis showed that HI and BMI(score) were significant independent predictors of SBP(score) or DBP(score). Obese and hypertensive patients had a higher HI, AHI, and incidence of OSAS (64% vs. 29%) than the obese and normotensive patients. In conclusion, HI had a significant correlation with the degree of hypertension in obese patients, which could not be attributed to the degree of obesity. These findings are consistent with the hypothesis that OSAS is one of the reasons why some obese children are hypertensive and some are not.

Interventional radiology for renovascular hypertension in children

Pediatric renovascular hypertension is an uncommon but important clinical problem. Atherosclerosis is rare in children, who typically suffer from fibromuscular dysplasia, neurofibromatosis type 1, Williams syndrome, or certain other rare conditions. Children with renovascular disease often have involvement of other arteries including the aorta and mesenteric and cerebral vessels. The pediatric interventional radiology service has a vital role in the diagnosis, evaluation, and treatment of renovascular hypertension. Renal vein renin sampling appears to be more useful in children than in adults, because their arterial disease is more often bilateral and segmental. Diagnostic angiography is still superior to less-invasive methods of imaging the renal arteries, especially the smaller branches. Interventional options include angioplasty, stenting, and ethanol ablation. Angioplasty is almost always technically successful and usually gives a worthwhile clinical improvement. Stenting is only used in children when angioplasty fails. Ethanol embolization may be appropriate in children with focal renin-producing areas that are untreatable by angioplasty.

The renin angiotensin system in childhood hypertension: selective increase of angiotensin-(1-7) in essential hypertension

OBJECTIVE

We examined the activity of the renin-angiotensin system (RAS) in normotensive and hypertensive children.

STUDY DESIGN

Hypertensive patients (12 with renovascular hypertension and 15 with essential hypertension) and 32 normotensive subjects were evaluated at a Pediatric Nephrology Center. Blood samples for plasma renin activity (PRA) and angiotensin peptides measurements were obtained once from normotensive subjects and before and after treatment from hypertensive patients. Plasma samples were extracted using Bond-Elut cartridges (Analytichem International, Harbor City, Calif), and peptide concentrations were determined by radioimmunoassay (RIA).

RESULTS

PRA, Angiotensin I (Ang I), Angiotensin II (Ang II), and Angiotensin-(1-7) [Ang-(1-7)] levels were significantly higher in renovascular hypertensive patients than in normotensive children (3.3 +/- 1.2 vs 0.40 +/- 0.22 ng Ang I/mL/hour, 81.4 +/- 24.8 vs 26.4 +/- 13.4 pg/mL, 59.3 +/- 17.0 vs 21.4 +/- 8.7 pg/mL, 41.0 +/- 10.5 vs 16.2 +/- 7.9 pg/mL, respectively). The surgical treatment normalized blood pressure, PRA, and angiotensins levels. In contrast with renovascular disease, only Ang-(1-7) levels were significantly increased in essential hypertensive patients compared with normotensive (78.8 +/- 22.8 vs 16.2 +/- 7.9 pg/mL). Treatment with calcium channel blockers did not alter the RAS measurements.

CONCLUSION

Our data show different RAS profiles in childhood hypertension and suggest a blood pressure-independent change of Ang-(1-7) in essential hypertension.

Twenty-four-hour ambulatory blood pressure in children with sleep-disordered breathing

Obstructive sleep apnea causes intermittent elevation of systemic blood pressure (BP) during sleep. To determine whether obstructive apnea in children has a tonic effect on diurnal BP, 24-hour ambulatory blood pressure was obtained from 60 children with mean age of 10.8 +/- 3.5 years. Thirty-nine children had obstructive apnea and 21 had primary snoring. Children with obstructive apnea had significantly greater mean BP variability during wakefulness and sleep, a higher night-to-day systolic BP, and a smaller nocturnal dipping of mean BP. Variability of mean arterial pressure during wakefulness was predicted by the desaturation, body mass, and arousal indices, whereas variability during sleep was predicted by apnea-hypopnea and body mass indices. Nocturnal BP dipping was predicted by the desaturation index. There were no significant differences in systolic, diastolic, or mean arterial BP during sleep between the groups. Diastolic BP during wakefulness was significantly different between the groups and correlated negatively with apnea-hypopnea index. We conclude that obstructive apnea in children is associated with 24-hour BP dysregulation and that, independent of obesity, the frequency of obstructive apnea, oxygen desaturation, and arousal contributes to abnormal BP control.

Abnormal blood pressure in prepubertal children with sleep-disordered breathing

The purpose of this study was to investigate the association between low blood pressure (BP) with mild symptoms of orthostatism, sleep-disordered breathing (SDB) and tilt test results in 7- to 12-y-old children. A retrospective chart review of 301 children, ages 7 to 12 y, was initially performed to evaluate the frequency of abnormal BP measurements. Then a prospective study was performed on 7- to 12-y-old prepubertal children with SDB, looking for both abnormal BP and mild orthostatism. All children had polysomnography. Those identified with abnormal (high or low) BP measurements (called "BP outliers") were studied with a new polysomnogram followed by a head-up tilt test as an indicator of autonomic activity. Four of the children with low BP were treated with nasal continuous positive airway pressure and received a second head-up tilt test 3.5 to 7 mo after starting treatment. The prospective study included 78 children, eight of whom were BP outliers. Seven of these outliers had low BP. Compared with all of the SDB subjects, SDB subjects with low BP and indicators of mild orthostatic hypotension had a significantly higher incidence of craniofacial dysmorphism, symptoms of SDB early in life, chronically cold extremities, and dizziness on standing up (chi2, p = 0.01 to 0.0001). They had a significantly greater drop in BP without evidence of autonomic neuropathy than all other children on head-up tilt testing (Kruskal-Wallis ANOVA with Bonferroni adjustment, p = 0.001 to 0.0001). However, the normotensive SDB controls also had significantly different BP drops than the normal controls (p = 0.0001). The four children placed on nasal continuous positive airway pressure had a nonsignificant trend toward normalization of tilt test response. SDB in prepubertal children can lead to different abnormal stimulation of the autonomic nervous system, with different impacts on BP. The severity and frequency of oxygen saturation drops during sleep, nonhypoxic increases in respiratory effort, and the duration of abnormal breathing are suspected of playing a role in the difference in autonomic nervous system stimulation.