Non-obese Adolescents Research Articles

Cortisol response to the Trier Social Stress Test among Chinese adolescents

To compare obese and non-obese adolescents in terms of their salivary cortisol response to the Trier Socia l Stress Test ( TSST). This is a cross - sectional study involving 41 healthy adolescents aged 12-14 years in the city of Shenyang, China. The TSST response was determined using salivary cortisol measurements, and measurements were repeated after the test period. Repeated-measures ANOVA was performed to compare salivary cortisol levels between groups. The male group comprised of 16 individuals (10 obese and 6 non-obese), and the female group comprised 25 individuals ( 13 obese and 12 non-obese). ANOVA with repeated measures demonstrated that weight status (obese or non-obese) had a significant main effect on the measures of salivary cortisol levels during the TSST among females but not males. The finding suggested that weight status is associated with cortisol response to psychological stress among Chinese adolescent girls.

Grosor de la íntima-media de la arteria carótida en adolescentes obesos y su relación con el síndrome metabólico

Introduction: Obese adolescents have higher cardiovascular risk (CVR). Intima-media thickness (IMT) detects early arterial vascular compromise. Objective: To evaluate whether obese adolescents have higher vascular compromise measured by IMT than nonobese adolescents, and if this is greater in those with metabolic syndrome (MS). Method: The study group (SG), obese children (BMI/ age > p95), with and without MS and control group (CG), non-obese (BMI/age p10-85) and non nutritional or endocrine disease. We measured serum lipids, oral glucose tolerance test with insulin and carotid artery ultrasound. To evaluate the differences between test groups we used parametric and nonparametric statistics. Results: We evaluated 45 obese adolescents (20 women), 19 with MS, age 13 (9-16) years and 18 controls (14 women), aged 13 (11-16) years. IMT of carotid bulb and internal carotid artery (ICA) were significantly higher in SG than CG (0.54 vs. 0.34, 0.34 vs. 0.25, p < 0.05). There was no difference between obese groups. IMT of ICA and bulb correlated positively with BMIz (r = 0.3 and 0.6, p < 0.05) and with waist circumference (CC) (r = 0.3 and 0.55, p < 0, 05). IMT of ICA was positively correlated with fasting insulin, HOMA and systolic blood pressure. In multivariate analysis only BMI and CC were associated independently to IMT. Conclusion: Obesity is an early risk factor for cardiovascular damage measured by IMT and IMT of ICA demonstrated a higher correlation with cardiovascular risk factors.

Accuracy of predictive equations for resting energy expenditure (REE) in non-obese and obese Korean children and adolescents.

Weight-controlling can be supported by a proper prescription of energy intake. The individual energy requirement is usually determined through resting energy expenditure (REE) and physical activity. Because REE contributes to 60-70% of daily energy expenditure, the assessment of REE is very important. REE is often predicted using various equations, which are usually based on the body weight, height, age, gender, and so on. The aim of this study is to validate the published predictive equations for resting energy expenditure in 76 normal weight and 52 obese Korean children and adolescents in the 7-18 years old age group. The open-circuit indirect calorimetry using a ventilated hood system was used to measure REE. Sixteen REE predictive equations were included, which were based on weight and/or height of children and adolescents, or which were commonly used in clinical settings despite its use based on adults. The accuracy of the equations was evaluated on bias, RMSPE, and percentage of accurate prediction. The means of age and height were not significantly different among the groups. Weight and BMI were significantly higher in obese group (64.0 kg, 25.9 kg/m2) than in the non-obese group (44.8 kg, 19.0 kg/m2). For the obese group, the Molnar, Mifflin, Liu, and Harris-Benedict equations provided the accurate predictions of > 70% (87%, 79% 77%, and 73%, respectively). On the other hand, for non-obese group, only the Molnar equation had a high level of accuracy (bias of 0.6%, RMSPE of 90.4 kcal/d, and accurate prediction of 72%). The accurate prediction of the Schofield (W/WH), WHO (W/WH), and Henry (W/WH) equations was less than 60% for all groups. Our results showed that the Molnar equation appears to be the most accurate and precise for both the non-obese and the obese groups. This equation might be useful for clinical professionals when calculating energy needs in Korean children and adolescents.

Impact of insulin resistance and obesity on elevated blood pressure in Chinese children and adolescents: The BCAMS study

Objective: Insulin resistance (IR) in the obese is closely related with cardiovascular diseases and their risk factors not only in adults but also in children and adolescents. We aimed to elucidate whether insulin resistance in non-obese children and adolescents is related with elevated blood pressure (BP). Methods: Subjects were recruited from a cross-sectional population-based survey: the Beijing Child and Adolescent Metabolic Syndrome (BCAMS) study. The present sample of 3480 students (1774 boys, 51%) was drawn from children aged 6 to 18 years who underwent physical examinations and fasted before blood testing. Obese was defined by age and gender-specific body mass index cutoffs of China. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated as fasting insulin (mU/L)×fasting glucose (mmol/L)/22.5. HOMA-IR levels above the highest quartile (>3.09 for boys and >2.83 for girls) were defined as IR. Participants were divided as four groups, i.e. normal group (non-obese and no IR, n=1923), IR group (non-obese but IR, n=338), obese group (obese but no IR, n=684) and obese combined IR group (n=535). Elevated BP was defined by systolic BP and/or diastolic BP equal to or greater than the 95th percentile for age and gender. Results: In obese combined IR groups, both systolic and diastolic BP levels were highest, followed by the obese, IR and normal groups (P<0.001 for trend) with age, gender and puberty adjusted. Prevalence of elevated BP was 8.2%, 16.1%, 29.2% and 38.3% in normal, IR, obese and obese combined IR groups, respectively (χ2=335.627, P<0.001 for trend). Adjusting for age, gender and puberty, compared with normal group, odds ratios and 95% confidence intervals of IR, obese and obese combined IR on elevated BP were 2.10 (1.50–2.96), 4.54 (3.56–5.80) and 6.21 (4.84–7.96), respectively. Conclusion: IR independently increases the risk of elevated BP not only in obese but also in non-obese children and adolescents.

Blood pressure variability in 24 hours in obese and non-obese adolescents with breast development 4 and 5 of Tanner's criteria

The aim of the study was to investigate the blood pressure variability during 24 h by using ambulatory blood pressure monitoring (ABPM) in a group of obese and non-obese female adolescents with breast development status 4 and 5 of Tanner´s criteria. A cross-sectional study was conducted at the Cardiovascular Research Institute, Mexico. All subjects underwent 24 h non-invasive ABPM recording device. Pubertal status was determined by breast development. office systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR). Height, weight, body mass index (BMI), waist and hip circumferences, arm circumference, waist to hip ratio (W/H), and skinfold thickness measurements: triceps, subscapular, abdominal and supraspinal. Fifty-nine adolescents 13-16 years old; 29 obese (BMI 31.2±4.0), and 30 non- obese (BMI 21.2±2.2). Obese vs. non-obese: Office SBP 116.9 vs. 105.9±9.3 mmHg (p<0.001); ABPM in 24 h: SBP 113.8±6.3 vs. 107.6±5.7 mmHg (p<0.001); diurnal SBP 117.3 mmHg vs. 111.2 mmHg (p<0.001); nocturnal SBP 105.5±8 vs. 99.4 mmHg; absolute variability in 24 h DBP 10.0±1.8 vs. 8.7±1.5 (p<0.003); coefficient of variation 24 h DBP 17.3±3 vs. 15.4±2.6% (p<0.05); systolic non-dipper 16 (55.2%) vs. 9 (30%) (p<0.05); pulse pressure 24 h 49.3±8 vs. 43.5±9 mmHg (p<0.01). Obese adolescents are presenting changes in BP variability during 24-h in comparison with nonobese adolescents; it also includes higher pulse pressure. Thus, these can be early indicators for the development of hypertension or other cardiovascular diseases in the adult life.

Obesity, cardiovascular fitness, and physically active adolescents’ motivations for activity: A self-determination theory approach

Objectives Overweight and obesity pose significant health problems for adolescents. Rates of overweight and obesity in children have increased 45% in the last decade and have increased three-fold since 1980. Because children who are physically active are at lower risk for the development of obesity, it is important to understand some of the factors that influence children’s physical activity patterns. The purpose of this study was to examine the relationship between motivation, cardiorespiratory fitness, and weight status, defined as obese or non-obese. We predicted that the association between motivation and weight status would become non-significant when controlling for cardiorespiratory fitness. Design The study employed a correlational, cross-sectional design. Method Participants included physically active middle school students ( N = 82. 51% female) of aged 12–14 years, who participated in the Teen Eating and Activity Mentoring in Schools (TEAMS) study aimed at improving health and preventing obesity among middle school students. Students completed attitudinal questionnaires about physical activity and self-determination on a computer-based system and participated in a number of fitness performance, health behavior, and anthropometric assessments. Results Non-obese adolescents showed higher intrinsic motivation scores than obese adolescents. Mediational analyses showed that cardiorespiratory fitness mediated the relationship between motivation and weight status. Conclusions The results of this study demonstrate differences in physical activity motivation as a function of adolescent weight status, but only for intrinsic motivation. As predicted, adolescents who were intrinsically motivated for physical activity were more fit and thereby less likely to be obese. The findings are consistent with self-determination theory.

Polycystic ovarian morphology in adolescents with regular menstrual cycles is associated with elevated anti-Mullerian hormone

The significance of polycystic ovarian morphology (PCOM) during adolescence is not clear. The aim of this study was to determine the relationship between PCOM and anti-Müllerian hormone (AMH), inhibin B, testosterone and insulin levels in healthy girls during the second decade of life. We also determined whether AMH could be used as a surrogate marker of PCOM during adolescence. Seventy-four non-obese adolescents (age range: 13.5-19.75 years old) with regular menstrual cycles participated in this study. Transabdominal ultrasound and blood samples were obtained during the follicular phase. PCOM was present in 33.8% of the subjects. Girls with PCOM had higher AMH levels than girls without PCOM (72.5 ± 6.1 versus 33.4 ± 2.6 pmol/l; P < 0.0001) and lower FSH levels (5.4 ± 0.3 versus 6.2 ± 0.2 mUI/ml; P < 0.036). Similar levels of inhibin B, androgens and LH were observed in girls with and without PCOM. PCOM prevalence and AMH levels were not associated with age (P = 0.745 and 0.2, respectively) or BMI-SDS (P = 0.951 and 0.096, respectively). AMH levels positively correlated with the of 2-5 mm follicle number. AMH levels ≥ 60.15 pmol/l had a sensitivity and specificity of 64.0 and 89.8%, respectively, to diagnose PCOM (area under the curve = 0.873). These data confirm that PCOM in healthy non-hyperandrogenic girls with regular menstrual cycles is prevalent and is not associated with hyperandrogenism. The elevated AMH and lower FSH levels observed in healthy girls with regular menses and PCOM suggest that this ovarian pattern is secondary to a larger number of 2-5 mm follicles. An elevated AMH level is suggestive of the presence of PCOM during adolescence.

MODY

Studies conducted at the University of Michigan for 60 years and at the University of Chicago for approximately 25 years form the basis of this review. As no field of study can develop or progress in isolation, we have included selected investigations performed in other centers. In the academic year 1949–1950, one of us (S.S.F.), while a first-year Fellow in Endocrinology and Metabolism at the University of Michigan (Jerome W. Conn, Division Chief), initiated a prospective, long-term study on the diagnosis, natural history, and clinical genetics of diabetes. Starting with known diabetic patients from the Diabetes Clinic, I recruited their apparently healthy and asymptomatic first-degree relatives (parents, brothers, sisters, and children) for routine oral glucose tolerance tests (OGTTs). As control subjects, I recruited young individuals, many of them students, physicians, nurses, dietitians, and their spouses, who did not have a family history of diabetes or of large newborn babies. The initial objectives were 1 ) to define the normal range for the OGTT, 2 ) to attempt to unmask the potential diabetic subjects who manifest normal glucose tolerance by the standard OGTT and determine whether the diabetogenic activity of cortisone could be used to uncover a subclinical defect in the metabolism of glucose, and 3 ) to carry out periodic follow-up over many years of the apparently healthy first-degree relatives of diabetic patients. In our first publication in 1954 (1), 19% of 152 relatives of known diabetic patients were found to have diabetes by OGTT and, moreover, some were as young as 10 years of age. The same prevalence of 19% was found when testing a larger sample of 438 relatives of known diabetic patients (2). In 1960, we reported that mild, asymptomatic diabetes occurs in nonobese children, adolescents, and young adults. Their diabetic glucose tolerance and fasting hyperglycemia improved or normalized …

The Efficacy and Safety of Valsartan in Obese and Non-Obese Pediatric Hypertensive Patients

This post hoc analysis assessed the efficacy and tolerability of valsartan for the treatment of hypertension in obese vs non-obese children and adolescents. After a 1-week antihypertensive washout period, 142 obese and 119 non-obese hypertensive children and adolescents aged 6 to 16 years were randomized to 2 weeks of once-daily treatment with valsartan 10 to 20 mg, 40 to 80 mg, or 80 to 160 mg, followed by re-randomization to either valsartan or placebo for an additional 2 weeks. Patients could continue to receive valsartan during an optional 52-week, open-label extension. Valsartan resulted in statistically significant (P<.05) and clinically relevant reductions in mean sitting blood pressure (BP), ranging from approximately 7/4 mm Hg (valsartan 10-20 mg) to 13/9 mm Hg (valsartan 80-160 mg) in both obese and non-obese patients. BP control was achieved in 44% of obese and 56% of non-obese patients. Following re-randomization, non-obese patients experienced an increase in BP during placebo treatment, albeit levels remained below baseline, whereas BP reductions were maintained in valsartan recipients (P<.05). The most frequent adverse events during the open-label phase were headache and fever. Valsartan provides similar antihypertensive efficacy in obese and non-obese hypertensive children and adolescents, with good tolerability in both patient populations.

Comparison of predictive equations for resting energy expenditure (REE) in obese and nonobese children and adolescents

The aim of this study was to assess the accuracy of predictive equations for REE in obese and nonobese young people. Subjects were 137 healthy Korean students (51 obese, 86 nonobese) aged 7–18y. REE(MREE) was measured by indirect calorimetry. Predicted REE(PREE) was calculated using the 9 equations(Schofield‐W/WH, WHO‐W/WH, Henry‐W/WH, IOM, Maffeis, and Kim equation). MREE of obese students (1558±308 kcal/day) was significantly higher than nonobese (1232±238 kcal/day). The validity of the equations was evaluated on basis of prediction accuracy (the percentage of subjects predicted within 10% of the MREE), difference, RMSPE, % difference, and limits of agreement of Bland‐Altman method between PREE and MREE. The most accurate for nonobese students was the Maffeis equation (prediction accuracy 61%, difference 0±161 kcal/day, RMSPE 109 kcal/day, % difference 2±12%). Although the WHO‐WH equation was the most reliable in obese (difference 113±164 kcal/day, RMSPE 165 kcal/day, % difference 7±10%), the prediction accuracy of the equation was only 53% and noteworthy errors exist. Thus, this study suggests that a new obesity‐specific predictive equation should be derived to estimate REE for obese students accurately.This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education, Science and Technology(2010‐0004472).

Obesity Hypertension in Adolescents: Epidemiology, Evaluation, and Management

The prevalence of hypertension among all adolescents is approximately 3.5%, with somewhat higher rates of prehypertension. Obesity affects approximately 20% of adolescents in the United States, and the prevalence of hypertension is much higher among obese adolescents compared with nonobese adolescents. As in other populations, the evaluation of elevated blood pressure in obese adolescents should begin with a confirmation of the blood pressure elevation, followed by a focused diagnostic work-up to detect possible secondary causes of hypertension. Primary therapy for obesity-related hypertension in adolescents begins with weight loss, and may include antihypertensive medications if target-organ damage or other indications for drug therapy are present. The emphasis of management should be reduction of future cardiovascular risk.

Ventilatory disorders and facial growth: Benefits of early genioplasty

The purpose of this prospective study was to determine whether combined functional genioplasty and orthodontic treatment in patients with vertical mandibular growth can be beneficial not only in achieving an esthetic outcome and orthodontic stability but also for the multi-disciplinary management of oral ventilation. Twenty-five non-obese adolescents (mean age: 14.6 ± 1.4 years) with vertical excess of the lower third requiring genioplasty received surgery following orthodontic treatment. All were predominantly mouth-breathers despite ENT treatment and rehabilitation. The functional before-after impact of genioplasty was examined in a clinical setting using polysomnography. Before genioplasty, 52% of the adolescents presented an upper airways resistance syndrome (UARS) with obstructive hypopnea and poor sleep quality. Three to 6 months after genioplasty, the mode of ventilation shifted from oral to nasal (p < 0.001). Lip seal was significantly restored with no contraction of the labio-mental muscles. All nighttime symptoms improved. The proportion of patients suffering from ronchopathy (pathological snoring), dry mouth and disturbed sleep dropped significantly (p = 0.08, p = 0.001, p = 0.0009, respectively). Respiratory events and sleep pattern became normal. Below, we present two clinical reports involving obstructive sleep apnea syndrome (OSAS). Genioplasty performed during puberty promotes spontaneous lip closure and helps restore nasal ventilation. It improves the obstructive disorder and its manifestations during sleep.

Growth hormone secretory pattern in non-obese children and adolescents with Prader-Willi syndrome

The aetiology of impaired growth hormone (GH) secretion in Prader-Willi syndrome (PWS) remains controversial due to the common occurrence of obesity. To further clarify whether suboptimal GH secretion in PWS is an artefact of excess weight, we evaluated both GH immunological activity and GH bioactivity after arginine administration in 23 non-obese PWS patients [seven females, aged 6.9 +/- 0.9 years, body mass index (BMI) SDS 0.63 +/- 0.26], in comparison with a control group of 32 healthy subjects, matched for age, gender and BMI (10 females, aged 7.9 +/- 0.3 years, BMI SDS 0.21 +/- 0.20). Serum GH concentration was measured with a time-resolved immunofluorometric assay (IFMA), while GH bioactivity was evaluated by the Nb2 cell bioassay. Serum IGF-I concentrations were measured by double-antibody RIA. GH mean peak after pharmacological stimulation was significantly lower in PWS individuals compared with controls when measured either by IFMA (6.05 +/- 1.23 microg/L vs. 23.7 +/- 1.06 microg/L, p < 0.0001) or by Nb2 (6.87 +/- 0.55 microg/L vs. 12.88 +/- 0.19 microg/L, p < 0.0001). Analysis of integrated GH secretion (AUC) confirmed that the PWS group differed significantly from the control subjects (387.9 +/- 76.1 microg/L/h vs. 1498.1 +/- 56.2 microg/L/h, p < 0.0001); the same result was obtained when the GH rise after arginine administration was expressed as nAUC (278.2 +/- 53.3 microg/L/h vs. 1443.6 +/- 52.5 microg/L/h, p < 0.0001). PWS patients had an IGF-I SDS significantly lower than those found in control subjects (p < 0.0001). Subnormal IGF-I values were present in 19 PWS individuals (82.6%) and two healthy controls (6.2%). These findings are in agreement with the hypothesis that a complex derangement of hypothalamus-pituitary axis occurs in PWS.

The effect of obesity on testicular function by insulin-like factor 3, inhibin B, and leptin concentrations in obese adolescents according to pubertal stages

Objectives The aim of the present study is to investigate the effect of obesity on testicular function by evaluating reproductive hormones, inhibinB, insulin-like 3(INSL3), and leptin, in obese and non-obese adolescents according to pubertal Tanner stages. Design and methods Eighty adolescent boys were grouped ( n = 20) as; Group1: obese-Tanner2, Group2: non-obese-Tanner2, Group3: obese-Tanner4, Group4: non-obese-Tanner4. Serum INSL3, luteinizing hormone, follicle-stimulating hormone, total testosterone, free testosterone, estradiol, sex hormone binding globulin, inhibin B and leptin levels were assessed in all groups. Results INSL3 levels were significantly lower in obese adolescents compared to non-obese boys ( p = 0.003, Tanner2) and ( p = 0.031, Tanner4). There was a negative correlation between INSL3 and leptin ( r = −0.468, p = 0.001). The negative correlation between INSL3 and BMISDS indicates that pubertal obesity leads to Leydig cell impairment. Conclusions This study demonstrated for the first time in the literature that obesity effects testicular Leydig cell function starting from Tanner stage 2.

Role of insulin resistance in non-obese adolescents.

Insulin resistance in the obese is closely related with cardiovascular diseases and their risk factors not only in adults but also in children and adolescents. We aimed to elucidate whether insulin resistance in non-obese adolescents is related with these conditions. A total of 74 non-obese high-school students (38 boys and 36 girls) were recruited. Anthropometry, blood pressure, fasting serum chemistry and insulin activity were measured. Subjects with a homeostasis model assessment-insulin resistance (HOMA-IR) level greater than the 75th percentile (> 2.25 for boys and > 2.89 for girls) were defined as insulin resistant. Non-obese boys with impaired insulin sensitivity had higher systolic blood pressure, lower HDL-cholesterol concentration, and fewer hours of vigorous exercise during weekdays, while non-obese girls with impaired insulin sensitivity had higher systolic blood pressure than their peers with normal insulin sensitivity. By multiple stepwise regression analysis, systolic blood pressure (p < 0.001) and the hours of vigorous exercise during weekdays (p < 0.03) were independently associated with HOMA-IR in boys, while systolic blood pressure (p < 0.0001) and serum concentrations of HDL-cholesterol (p < 0.01) were found in girls. In nonobese adolescents, insulin sensitivity is related with cardiovascular risk factors.

Metabolic predictors for early identification of fatty liver using doppler and B-mode ultrasonography in overweight and obese adolescents

(1) to evaluate the frequency of asymptomatic fatty liver disease (FLD) using both Doppler and B-mode ultrasound (US) in overweight and obese adolescents; (2) to compare metabolic findings of fatty liver (FL) assessed by two methods; and (3) to evaluate metabolic predictors of FL shown by these methods. Fifty-nine overweight and obese adolescents aged between 9.0 and 17.0 years and 41 non-obese healthy adolescents were included in this study. B-mode and right hepatic vein Doppler ultrasonography (US) were performed and anthropometric indices, lipid profiles, and adiponectin levels were evaluated in all adolescents. HDL-C levels were significantly lower in patients with FL detected by Doppler US compared to patients without FL (p < 0.05). HDL-C levels were inversely correlated with presence of FL assessed by two methods (r = -0.285, p = 0.004; r = -0.328, p = 0.001, respectively) and adiponectin levels were correlated with presence of FL only detected by B-mode US (r = -0.263, p = 0.008). Adiponectin levels were significantly lower in patients with FL than those without FL assessed by B-Mode US (p = 0.049). Multiple regression analysis revealed that HDL-C levels was the most important predictor of FL assessed by Doppler US (p = 0.027), while body mass index was the determinant of FL assessed by two methods (p < 0.001) in asymptomatic overweight and obese adolescents. It was found that FLD, identified by both B-mode and Doppler US, is seen frequently in asymptomatic overweight and obese adolescents. Elevated BMI is associated with increased risk of FL assessed by two ultrasonographic methods. When using Doppler US, low HDL-C levels can be used as a good predictor for presence of FLD in overweight and obese adolescents.

SHA 32. Vitamin D status is associated with cardiometabolic risk factors among non-obese Arab children and adolescents

SHA 32. Vitamin D status is associated with cardiometabolic risk factors among non-obese Arab children and adolescents

Broncoespasmo induzido pelo exercício em adolescentes asmáticos obesos e não-obesos

OBJETIVO: Avaliar e comparar a frequência e intensidade do broncoespasmo induzido pelo exercício (BIE) em adolescentes asmáticos obesos e não-obesos. MÉTODOS: Estudo transversal e descritivo realizado com 39 adolescentes de ambos os sexos, com idade entre dez e 16 anos, divididos em dois grupos conforme o histórico clínico de asma e/ou rinite alérgica e o índice de massa corporal: asmáticos obesos (n=18); asmáticos não-obesos (n=21). Utilizou-se o teste de broncoprovocação com exercício para a avaliação do BIE, considerando-se positiva uma diminuição do volume expiratório forçado no primeiro segundo (VEF1) &gt;15% do valor pré-exercício. Para avaliar a intensidade e a recuperação do BIE, foram calculadas a queda percentual máxima do VEF1 (QM%VEF1) e a área acima da curva (AAC0-30). A análise estatística utilizou o teste exato de Fischer para comparar a frequência de BIE e o teste de Mann-Whitney para a intensidade e recuperação. Rejeitou-se a hipótese de nulidade se p&lt;0,05. RESULTADOS: Não houve diferença significativa na frequência de BIE entre os grupos de asmáticos obesos (50%) e não-obesos (38%). Entretanto, a queda máxima do VEF1 e a AAC0-30 foram maiores nos asmáticos obesos em comparação aos não-obesos (respectivamente 37,7% e 455 versus 24,5% e 214, p&lt;0,03). CONCLUSÕES: A obesidade não contribuiu para o aumento da frequência do BIE em asmáticos e não-asmáticos, entretanto, a obesidade contribuiu para o aumento da intensidade e do tempo de recuperação da crise de BIE em asmáticos

Impairment of cardiovascular autonomic pattern in obese adolescents with Type 2 diabetes mellitus

The aim of this study was to assess the behaviour of insulin sensitivity and insulin resistance (IR) indexes in a group of obese adolescents with Type 2 diabetes mellitus (T2DM) in comparison to obese adolescents without diabetes and normal controls, moreover to compare these parameters with the cardiac autonomic pattern. Seven T2DM obese (12.7 ± 0.5 yr), 18 obese without T2DM, and 10 nonobese control adolescents age matched were studied. In all subjects we performed oral glucose tolerance test (OGTT) with insulin and glucose determination, 24-h electrocardiogram Holter, blood pressure monitoring, ecohocardiogram. serum lipids were significantly higher in obese and T2DM. Insulin sensitivity was significantly reduced in T2DM and obese vs controls; T2DM showed a more pronounced oral glucose insulin sensitivity (OGIS) reduction vs obese. Both obese and T2DM presented an higher IR. T2DM showed an impaired β-cell function, with insulin areas under the curve and disposition index significantly reduced in comparison to controls and obese who showed similar values. A progressive reduction of vagal indexes and an increase of sympathetic indexes were found in obese adolescents and were more pronounced in T2DM. These parameters were correlated with OGIS and β-cell function parameters in both obese and T2DM adolescents. T2DM showed a significant relative wall thickness increase suggesting a trend toward concentric remodeling. In conclusion, T2DM adolescents are characterized by a more marked IR reduced β-cell function in comparison to non-diabetic obese. These modifications may lead to an early impairment of the autonomic pattern.

Iron stores, liver transaminase levels and metabolic risk in healthy teenagers

Iron overload may contribute to the pathogenesis of insulin resistance. We aimed to investigate the relationship among iron stores, liver transaminases and components of the metabolic syndrome in healthy teenagers in a cross-sectional study. We determined body mass index (BMI), waist-to-hip-ratio (WHR), blood pressure, liver ultrasound, serum lipids, insulin, fasting glucose, liver transaminase levels, hsCRP, iron parameters in 325 of 341 (95.3%) students (234 men, 16.7 +/- 1.7 years; 91 women, 16.5 +/- 1.7 years) of one single high school. Male and female study participants were allocated to increasing quartiles of body iron stores as assessed by sTfr/ferritin and alanine aminotranspeptidase (ALT) levels, and the distribution of cardiometabolic risk factors along quartiles was analysed. Regression analysis was performed to confirm the independent relationship between parameters. In male students, BMI, WHR, systolic and diastolic blood pressure, serum triglyceride levels and hsCRP were higher in the top sTfR/ferritin and ALT quartiles compared with the lowest quartiles (P < 0.01 for all parameters). In female students, sTfR/ferritin were not associated with antropomorphic cardiometabolic risk factors but with insulin resistance (HOMA-IR, P = 0.046). Moreover, ALT levels were independently related to BMI, waist and hip circumference, systolic blood pressure, serum triglyceride and insulin concentrations (P < 0.05 for all parameters) in female students. These results provide evidence for linkage among body iron stores, transaminase activity and the prevalence of cardiometabolic risk factors in apparently healthy, non-obese adolescents even within the range of normal laboratory and anthropomorphic values and suggest that iron stores should be investigated as a potentially modifiable risk factor in healthy teenagers.