The threshold value for identifying insulin resistance (HOMA-IR) in an admixed adolescent population: A hyperglycemic clamp validated study

ABSTRACT Objectives: To validate the homeostasis model assessment (HOMA) of insulin resistance (IR) as a surrogate to the hyperglycemic clamp to measure IR in both pubertal and postpubertal adolescents, and determine the HOMA-IR cutoff values for detecting IR in both pubertal stages. Subjects and methods: The study sample comprised 80 adolescents of both sexes (aged 10-18 years; 37 pubertal), in which IR was assessed with the HOMA-IR and the hyperglycemic clamp. Results: In the multivariable linear regression analysis, adjusted for sex, age, and waist circumference, the HOMA-IR was independently and negatively associated with the clamp-derived insulin sensitivity index in both pubertal (unstandardized coefficient - B = −0.087, 95% confidence interval [CI] = −0.135 to −0.040) and postpubertal (B = −0.101, 95% CI, −0.145 to −0.058) adolescents. Bland-Altman plots showed agreement between the predicted insulin sensitivity index and measured clamp-derived insulin sensitivity index in both pubertal stages (mean = −0.00 for pubertal and postpubertal); all P > 0.05. The HOMA-IR showed a good discriminatory power for detecting IR with an area under the receiver operator characteristic curve of 0.870 (95% CI, 0.718-0.957) in pubertal and 0.861 (95% CI, 0.721-0.947) in postpubertal adolescents; all P < 0.001. The optimal cutoff values of the HOMA-IR for detecting IR were > 3.22 (sensitivity, 85.7; 95% CI, 57.2-98.2; specificity, 82.6; 95% CI, 61.2-95.0) for pubertal and > 2.91 (sensitivity, 63.6; 95% CI, 30.8-89.1, specificity, 93.7; 95%CI, 79.2-99.2) for postpubertal adolescents. Conclusion: The threshold value of the HOMA-IR for identifying insulin resistance was > 3.22 for pubertal and > 2.91 for postpubertal adolescents.

The threshold value for identifying insulin resistance (HOMA-IR) in an admixed adolescent population: A hyperglycemic clamp validated study.

Objective: To validate the homeostasis model assessment (HOMA) of insulin resistance (IR) as a surrogate to the hyperglycemic clamp to measure IR in both pubertal and postpubertal adolescents, and determine the HOMA-IR cutoff values for detecting IR in both pubertal stages. Subjects and methods: The study sample comprised 80 adolescents of both sexes (aged 10-18 years; 37 pubertal), in which IR was assessed with the HOMA-IR and the hyperglycemic clamp. Results: In the multivariable linear regression analysis, adjusted for sex, age, and waist circumference, the HOMA-IR was independently and negatively associated with the clamp-derived insulin sensitivity index in both pubertal (unstandardized coefficient - B = -0.087, 95% confidence interval [CI] = -0.135 to -0.040) and postpubertal (B = -0.101, 95% CI, -0.145 to -0.058) adolescents. Bland-Altman plots showed agreement between the predicted insulin sensitivity index and measured clamp-derived insulin sensitivity index in both pubertal stages (mean =-0.00 for pubertal and postpubertal); all P > 0.05. The HOMA-IR showed a good discriminatory power for detecting IR with an area under the receiver operator characteristic curve of 0.870 (95% CI, 0.718-0.957) in pubertal and 0.861 (95% CI, 0.721-0.947) in postpubertal adolescents; all P < 0.001. The optimal cutoff values of the HOMA-IR for detecting IR were > 3.22 (sensitivity, 85.7; 95% CI, 57.2-98.2; specificity, 82.6; 95% CI, 61.2-95.0) for pubertal and > 2.91 (sensitivity, 63.6; 95% CI, 30.8-89.1, specificity, 93.7; 95%CI, 79.2-99.2) for postpubertal adolescents. Conclusion: The threshold value of the HOMA-IR for identifying insulin resistance was > 3.22 for pubertal and > 2.91 for postpubertal adolescents.

Association between Pulmonary Function and Body Composition in Children and Adolescents with and without Obesity.

Lung function in children and adolescents with obesity must consider the coexistence of two complex and related phenomena: obesity and growth. The assessment of body composition can identify changes in respiratory dynamics arising, exclusively or jointly, from adiposity and lean body mass. This study aimed to compare pulmonary function and the dysanapsis indices of children and adolescents without asthma, with and without obesity, considering body composition, pubertal development, and physical activity practice. We performed a cross-sectional study with 69 participants, 41 (59.42%) of whom have obesity. All participants carried out spirometry and the assessment of, respectively, body composition by dual-energy X-ray absorptiometry, vital signs, pubertal development, and physical activity practice. In our data, the group with obesity had higher values of forced vital capacity (FVC) and lower values of the ratio between forced expiratory volume in one second and FVC (FEV1/FVC). Analyzing the entire sample, we found a positive correlation between FVC and a negative correlation between FEV1/FVC with fat mass markers. At the same time, inspiratory capacity, expiratory reserve volume, and peak expiratory flow were correlated with lean body mass markers. In addition, participants with obesity presented a lower dysanapsis index. In conclusion, children and adolescents with obesity showed increased FVC and reduced FEV1/FVC. Our findings are possibly related to the increase in fat mass, not to lean body mass. We hypothesize that these findings are associated with the dysanaptic growth pattern, which is higher in obesity, evidenced by the reduction of the dysanapsis index.

Concordance between whole- and half-body scans to evaluate body composition in dual-energy X-ray absorptiometry in children and adolescents with different nutritional and pubertal conditions.

OBJECTIVES: Evaluation of body composition is a relevant clinical instrument for the follow-up assessments of children and adolescents, and dual-energy X-ray absorptiometry (DXA) is an accurate method for the pediatric population. However, DXA has limited scan area for the obese population. Thus, half-body scans emerged as an alternative to evaluate individuals with obesity. The aim of this study was to compare the body composition of children and adolescents with whole- and half-body DXA scans, considering nutritional status, pubertal development, sex, and age. METHODS: This was a cross-sectional, analytical, and diagnostic intervention study with a sample of 82 participants of both sexes between 4 and 20 y of age. Body composition was evaluated by DXA using an iDXA bone densitometer (GE Healthcare Lunar, Madison, WI, USA). Two evaluations were performed: whole-body and half-body scans. The Bland-Altman correlation and linear regression tests were applied to identify the presence of association bias between the techniques. α = 0.05 was set. RESULTS: Of the 82 participants, 20 were excluded. A high correlation was observed between the data (correlation coefficient ∼0.999). Bland-Altman plots and regression analyses demonstrated correlation and randomness bias between whole- and half-body scan techniques in obese or normal weight participants for all DXA markers. CONCLUSIONS: The use of half-body scans was feasible and accurate to evaluate whole-body composition. The difference bias between techniques occurred randomly and was clinically irrelevant. A high correlation was observed between half- and whole-body analysis techniques.

Homeostatic model assessment of adiponectin (HOMA-Adiponectin) as a surrogate measure of insulin resistance in adolescents: Comparison with the hyperglycaemic clamp and homeostatic model assessment of insulin resistance.

BACKGROUND: Studies on adults have reported inverse association between the homeostatic model assessment (HOMA) of adiponectin (HOMA-Adiponectin) and the insulin resistance assessed by the glucose clamp technique. To our knowledge, in the pediatric population this association has not been previously investigated. OBJECTIVES: To evaluate the association between the HOMA-Adiponectin and the insulin resistance assessed by the glucose clamp technique in adolescents, and to compare the accuracy of HOMA-Adiponectin and HOMA-insulin resistance (HOMA-IR) for identifying insulin resistance. METHODS: This was a cross-sectional study of 56 adolescents (aged 10-18 years). Insulin resistance was assessed using the HOMA-IR, HOMA-Adiponectin and the hyperglycaemic clamp technique. The clamp-derived insulin sensitivity index, HOMA-Adiponectin, and HOMA-IR were log-transformed to get closer to a normal distribution before analysis. RESULTS: In the multivariable linear regression analysis controlling for sex and Tanner stage, HOMA-Adiponectin was inversely associated with the clamp-derived insulin sensitivity index (unstandardized coefficient [B] = -0.441; P < 0.001). After additional adjustment for waist circumference-to-height ratio, this association remained significant (B = -0.349; P = < 0.001). Similar results were observed when HOMA-IR replaced HOMA-Adiponectin in the model (B = -1.049 and B = -0.968 after additional adjustment for waist circumference-to-height ratio); all P < 0.001. The area under the receiver operating characteristic curve for predicting insulin resistance was 0.712 (P = 0.02) for HOMA-Adiponectin and 0.859 (P < 0.0001) HOMA-IR. CONCLUSIONS: The HOMA-Adiponectin was independently associated with insulin resistance and exhibited a good discriminatory power for predicting it. However, it did not show superiority over HOMA-IR in the diagnostic accuracy.

Bariatric surgery: is it reasonable before the age of 16?

OBJECTIVE:: to assess the severity of obesity in children and adolescents through the presence of comorbidities and the potential indication of bariatric surgery. METHODS:: we conducted a cross-sectional study with clinical and laboratory data of the first consultation of patients at the childhood obesity clinic at a tertiary hospital from 2005 to 2013. We divided the patients into groups with or without potential indication for surgery, and recorded age, gender, birth weight, age of obesity onset, BMI Z score, presence of acanthosis nigricans, blood pressure, total cholesterol and fractions, triglycerides, blood glucose and fasting insulin, HOMA1-IR, CRP and ESR. The group with potential indication for surgery included: BMI > 40 or between 35-40 with comorbidities (Triglycerides >130mg/dl, glucose levels >100mg/dl, HOMA1-IR >3.16, Total Cholesterol >200mg/dl, LDL >130mg/dl and HDL <45mg/dl), regardless of age, epiphysis consolidation and previous treatment. RESULTS:: of the 296 patients included in the study, 282 (95.3%) were younger than 16 years. The most frequent change was the HDL (63.2%), followed by HOMA1-IR (37.5%). Of the group of 66 patients with potential indication for surgery (22.3%), only ten (15.1%) had more than 16 years. Acanthosis nigricans, the average HOMA1-IR, insulin, CRP, ESR, age, BMI Z score and systolic and diastolic blood pressure were significant in the group with potential surgical indication. CONCLUSION:: bariatric surgery might be indicated by BMI and comorbidities in children and adolescents under 16 years. OBJETIVO:: avaliar a gravidade da obesidade em crianças e adolescentes pela presença de comorbidades e pela potencial indicação de cirurgia bariátrica. MÉTODOS:: estudo transversal com dados clínicos e laboratoriais da primeira consulta de pacientes do ambulatório de obesidade infantil em um hospital terciário no período de 2005 a 2013. Os pacientes foram divididos em grupos com ou sem potencial indicação cirúrgica, e associados com idade, sexo, peso de nascimento, idade de início da obesidade, escore z de IMC, presença de acantose nigricans, pressão arterial, colesterol total e frações, triglicérides, glicemia e insulina de jejum, HOMA1-IR, PCR e VHS. O grupo com potencial indicação cirúrgica incluiu: IMC >40 ou IMC entre 35-40 com comorbidades (Triglicérides >130mg/dl, Glicemia >100mg/dl, HOMA1-IR >3,16, Colesterol total >200mg/dl, LDL >130mg/dl e HDL <45mg/dl), independente da idade, consolidação das epífises e tratamento prévio. RESULTADOS:: de 296 pacientes incluídos no estudo, 282 (95,3%) tinham menos de 16 anos. A alteração mais frequente foi a do HDL (63,2%), seguido do HOMA1-IR (37,5%). Do grupo de 66 pacientes com potencial indicação cirúrgica (22,3%), apenas dez (15,1%) tinham mais de 16 anos. Acantose nigricans, as médias de HOMA1-IR, insulina, PCR, VHS, idade, escore z de IMC e pressões sistólica e diastólica foram significantes no grupo com potencial indicação cirúrgica. CONCLUSÃO:: os resultados sugerem que a cirurgia bariátrica, poderia estar indicada pelo IMC e presença de comorbidades, em crianças e adolescentes com menos de 16 anos.

Bariatric surgery: is it reasonable before the age of 16? / Cirurgia bariátrica: é razoável antes dos 16 anos de idade?

ABSTRACT Objective: to assess the severity of obesity in children and adolescents through the presence of comorbidities and the potential indication of bariatric surgery. Methods: we conducted a cross-sectional study with clinical and laboratory data of the first consultation of patients at the childhood obesity clinic at a tertiary hospital from 2005 to 2013. We divided the patients into groups with or without potential indication for surgery, and recorded age, gender, birth weight, age of obesity onset, BMI Z score, presence of acanthosis nigricans, blood pressure, total cholesterol and fractions, triglycerides, blood glucose and fasting insulin, HOMA1-IR, CRP and ESR. The group with potential indication for surgery included: BMI > 40 or between 35-40 with comorbidities (Triglycerides >130mg/dl, glucose levels >100mg/dl, HOMA1-IR >3.16, Total Cholesterol >200mg/dl, LDL >130mg/dl and HDL <45mg/dl), regardless of age, epiphysis consolidation and previous treatment. Results: of the 296 patients included in the study, 282 (95.3%) were younger than 16 years. The most frequent change was the HDL (63.2%), followed by HOMA1-IR (37.5%). Of the group of 66 patients with potential indication for surgery (22.3%), only ten (15.1%) had more than 16 years. Acanthosis nigricans, the average HOMA1-IR, insulin, CRP, ESR, age, BMI Z score and systolic and diastolic blood pressure were significant in the group with potential surgical indication. Conclusion: bariatric surgery might be indicated by BMI and comorbidities in children and adolescents under 16 years.

RESUMO Objetivo: avaliar a gravidade da obesidade em crianças e adolescentes pela presença de comorbidades e pela potencial indicação de cirurgia bariátrica. Métodos: estudo transversal com dados clínicos e laboratoriais da primeira consulta de pacientes do ambulatório de obesidade infantil em um hospital terciário no período de 2005 a 2013. Os pacientes foram divididos em grupos com ou sem potencial indicação cirúrgica, e associados com idade, sexo, peso de nascimento, idade de início da obesidade, escore z de IMC, presença de acantose nigricans, pressão arterial, colesterol total e frações, triglicérides, glicemia e insulina de jejum, HOMA1-IR, PCR e VHS. O grupo com potencial indicação cirúrgica incluiu: IMC >40 ou IMC entre 35-40 com comorbidades (Triglicérides >130mg/dl, Glicemia >100mg/dl, HOMA1-IR >3,16, Colesterol total >200mg/dl, LDL >130mg/dl e HDL <45mg/dl), independente da idade, consolidação das epífises e tratamento prévio. Resultados: de 296 pacientes incluídos no estudo, 282 (95,3%) tinham menos de 16 anos. A alteração mais frequente foi a do HDL (63,2%), seguido do HOMA1-IR (37,5%). Do grupo de 66 pacientes com potencial indicação cirúrgica (22,3%), apenas dez (15,1%) tinham mais de 16 anos. Acantose nigricans, as médias de HOMA1-IR, insulina, PCR, VHS, idade, escore z de IMC e pressões sistólica e diastólica foram significantes no grupo com potencial indicação cirúrgica. Conclusão: os resultados sugerem que a cirurgia bariátrica, poderia estar indicada pelo IMC e presença de comorbidades, em crianças e adolescentes com menos de 16 anos.

Hypertriglyceridemic Waist Phenotype Indicates Insulin Resistance in Adolescents According to the Clamp Technique in the BRAMS Study.

OBJECTIVE: This study aimed to identify cutoff points for detecting hypertriglyceridemic waist phenotype (HTWP) in adolescents and to investigate the association of the HTWP with insulin resistance (IR) and metabolic syndrome components. METHODS: A multicentric cross-sectional study of 861 adolescents (10-19 years of age, 504 girls) was conducted. Pubertal stage, anthropometric, and laboratory parameters were assessed. IR was assessed by Homeostasis Model Assessment for Insulin Resistance (HOMA1-IR) index and hyperglycemic clamp (n = 80). HTWP was defined by the presence of increased plasma triglycerides (TGs) and increased waist circumference (WC) according to cutoff points obtained in ROC curve analysis given the HOMA1-IR index as a reference method. RESULTS: Cutoffs for WC and TGs, with a higher sum of sensitivity (S) and specificity (E), were, respectively: >84 cm (S:65.1%, E:71.9%) and >87 mg/dL (S:65.1%, E:73.4%) in pubertal girls; >88.5 cm (S:80.2%, E:60.2%) and >78 mg/dL (S:60.5%, E:53.2%) in postpubertal girls; >94 cm (S:73.1%, E:83.1%) and >79 mg/dL (S:61.5%, E:60.2%) in pubertal boys; and >99 cm (S:81.3%, E:78.7%) and >86 mg/dL in postpubertal boys (S:68.1%, E:60.7%). HTWP frequency was 27.5%. In the phenotype presence, after adjustment for age and pubertal stage, blood pressure and fasting glucose levels were elevated and high-density lipoprotein cholesterol was lower (p < 0.001). Adolescents with the HTWP showed more IR, evaluated both by the HOMA1-IR and by the clamp test (p < 0.003). CONCLUSION: The findings suggest HTWP as an IR status in adolescents. Cutoff point standardization for gender and pubertal stage, combined with the ease of application of the method, may allow their use for screening adolescents who would most benefit from lifestyle changes.

Association of Sleep Deprivation With Reduction in Insulin Sensitivity as Assessed by the Hyperglycemic Clamp Technique in Adolescents.

IMPORTANCE: The association between short sleep duration and decreased insulin sensitivity in adolescents has been described. However, to our knowledge, no studies have investigated this association measuring insulin sensitivity by the hyperglycemic clamp technique. OBJECTIVES: To compare the distributions of parameters of insulin resistance in adolescents with sleep deprivation vs adequate sleep, and to investigate the association between sleep deprivation and insulin sensitivity. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional multicenter study using data from the Brazilian Metabolic Syndrome Study conducted from June 29, 2011, to December 3, 2014, at an obesity outpatient clinic at the University of Campinas and public schools, with a convenience sample of 615 adolescents aged 10 to 19.9 years with a body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) for age and sex at the fifth percentile or higher. A subsample of 81 adolescents underwent the hyperglycemic clamp technique. MAIN OUTCOMES AND MEASURES: The self-reported sleep duration was used to classify the population into 2 groups: adolescents with sleep deprivation (<8 hours/night) and adolescents with adequate sleep (≥8 hours/night). Insulin sensitivity was assessed using the hyperglycemic clamp technique. RESULTS: Among the 615 adolescents (56.3% female; median age, 15.9 years [interquartile range, 12.9-17.8 years]) included in the sample, the mean (SD) sleep duration was 7.9 (1.7) hours/night. The adolescents with sleep deprivation (n = 257) compared with those with adequate sleep (n = 358) had a higher median (interquartile range) age (17.0 [15.4-18.3] vs 14.1 [11.8-16.9] years), BMI (25.0 [21.2-29.3] vs 23.1 [19.5-27.6]), waist circumference (83.0 [73.5-95.4] vs 79.0 [68.5-91.0] cm), sagittal abdominal diameter (17.9 [15.8-20.8] vs 17.0 [15.0-19.8] cm), neck circumference (35.2 [33.0-38.0] vs 33.0 [30.0-35.5] cm), uric acid level (4.9 [4.0-5.8] vs 4.5 [3.7-5.5] mg/dL), and white blood cell count (7000 [5900-8200] vs 6600 [5600-7800] cells/µL) (all P < .05). Moreover, the adolescents with sleep deprivation had a lower median (interquartile range) insulin sensitivity index compared with those with adequate sleep (0.10 [0.05-0.21] vs 0.21 [0.09-0.33] mg · kgfat-free mass-1 · min-1 · mU/L × 100, respectively; difference, -0.01; 95% CI, -0.01 to -0.00; P = .02). After controlling for age and sex in the multivariate regression model, sleep deprivation remained an independent predictor for those variables. In the sleep deprivation group, BMI and central distribution of fat were higher in all categories of adiposity. CONCLUSIONS AND RELEVANCE: Sleep deprivation (<8 hours of sleep per night) is associated with centripetal distribution of fat and decreased insulin sensitivity in adolescents. Therefore, investigations of sleep duration and sleep quality in adolescents should be included in clinical practice to promote, through health education, the eradication of the health risks associated with sleep restriction.

The relationship between physical functional capacity and lung function in obese children and adolescents.

BACKGROUND: There is no consensus regarding obesity repercussions for lung function in children and adolescents. Therefore, the aim of the study was to determine whether obesity is associated with poor physical conditioning and damaged lung function in children and adolescents, and to correlate lung function with six-minute walk test (6MWT) results. METHODS: This cross-sectional study included 38 obese subjects of both sexes, ranging between 5 and 17 years of age, as well as 56 control subjects paired by sex and age for the 6MWT, and 39 subjects for spirometry. Subjects performed spirometry according to the guidelines of the American Thoracic Society (ATS) and the European Respiratory Society. The obese group repeated spirometry after receiving bronchodilator (BD) treatments. Physical performance was evaluated via the 6MWT according to ATS guidelines. RESULTS: The obese group demonstrated lower forced expiratory volumes in the first second compared with the control group based on forced vital capacity indices (p < 0.01), findings consistent with airway obstruction in 36.8% of patients in the obese group. Walking distances were shorter in the obese group than in the control group. Changes in lung function did not correlate directly with performance on the 6MWT among obese patients. However, there was a correlation between lung function and variables indicative of effort during exercise. CONCLUSION: In the present study, the obese group walked shorter distances and demonstrated lower values in some markers of lung function. However, there is no relationship between their physical conditions and these test results. Therefore, we cannot conclusively state that poor physical performance results from damaged pulmonary function.

Air stacking: effects of Pilates mat exercises on muscle strength and on pulmonary function in patients with cystic fibrosis.

OBJECTIVE: To analyze the effects of Pilates mat exercises in patients with cystic fibrosis (CF). METHODS: This was a clinical trial involving 19 CF patients recruited from either the CF Outpatient Clinic of the State University at Campinas Hospital de Clínicas or the Children's Institute of the University of São Paulo School of Medicine Hospital das Clínicas. All of the patients performed Pilates mat exercises for four months (one 60-min session per week). The variables studied (before and after the intervention) were respiratory muscle strength, MIP, MEP, FVC, and FEV1. RESULTS: After the intervention, MIP was significantly higher in the male patients (p = 0.017), as were MIP and MEP in the female patients (p = 0.005 and p = 0.007, respectively). There were no significant differences between the pre- and post-intervention values of FVC or FEV1, neither in the sample as a whole nor among the patients of either gender. CONCLUSIONS: Our results show that Pilates mat exercises have beneficial effects on respiratory muscle strength in CF patients.

Effects of Pilates mat exercises on muscle strength and on pulmonary function in patients with cystic fibrosis / Efeitos do método Pilates na força muscular e na função pulmonar de pacientes com fibrose cística

OBJECTIVE: To analyze the effects of Pilates mat exercises in patients with cystic fibrosis (CF). METHODS: This was a clinical trial involving 19 CF patients recruited from either the CF Outpatient Clinic of the State University at Campinas Hospital de Clínicas or the Children's Institute of the University of São Paulo School of Medicine Hospital das Clínicas. All of the patients performed Pilates mat exercises for four months (one 60-min session per week). The variables studied (before and after the intervention) were respiratory muscle strength, MIP, MEP, FVC, and FEV1. RESULTS: After the intervention, MIP was significantly higher in the male patients (p = 0.017), as were MIP and MEP in the female patients (p = 0.005 and p = 0.007, respectively). There were no significant differences between the pre- and post-intervention values of FVC or FEV1, neither in the sample as a whole nor among the patients of either gender. CONCLUSIONS: Our results show that Pilates mat exercises have beneficial effects on respiratory muscle strength in CF patients. .

OBJETIVO: Analisar os efeitos do método Pilates em pacientes com fibrose cística (FC). MÉTODOS: Foi realizado um ensaio clínico, casuística de 19 pacientes com FC. Os pacientes foram recrutados no Ambulatório de FC do Hospital de Clínicas da Universidade Estadual de Campinas e no Instituto da Criança do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Todos os pacientes foram submetidos a uma sessão semanal de Pilates de 60 min durante quatro meses. As variáveis estudadas, antes e após a intervenção, foram força muscular respiratória, PImáx, PEmáx, CVF e VEF1. RESULTADOS: Houve um aumento significativo na PImáx nos pacientes do sexo masculino (p = 0,017), enquanto houve aumentos significativos na PImáx e PEmáx nos pacientes do sexo feminino (p = 0,005 e p = 0,007, respectivamente) após a intervenção. Não houve diferenças significativas nos valores de CVF e VEF1 antes e após a intervenção no grupo total de participantes, nem nos subgrupos em relação ao gênero. CONCLUSÕES: Os resultados deste estudo mostraram os efeitos benéficos da aplicação do método Pilates na força muscular respiratória nos pacientes estudados. (Registro Brasileiro de Ensaios Clínicos - ReBEC; número de identificação RBR-86vp8x [http://www.ensaiosclinicos.gov.br]) .

Neck circumference as a new anthropometric indicator for prediction of insulin resistance and components of metabolic syndrome in adolescents: Brazilian Metabolic Syndrome Study.

OBJECTIVE: To evaluate the correlation between neck circumference and insulin resistance and components of metabolic syndrome in adolescents with different adiposity levels and pubertal stages, as well as to determine the usefulness of neck circumference to predict insulin resistance in adolescents. METHODS: Cross-sectional study with 388 adolescents of both genders from ten to 19 years old. The adolescents underwent anthropometric and body composition assessment, including neck and waist circumferences, and biochemical evaluation. The pubertal stage was obtained by self-assessment, and the blood pressure, by auscultation. Insulin resistance was evaluated by the Homeostasis Model Assessment-Insulin Resistance. The correlation between two variables was evaluated by partial correlation coefficient adjusted for the percentage of body fat and pubertal stage. The performance of neck circumference to identify insulin resistance was tested by Receiver Operating Characteristic Curve. RESULTS: After the adjustment for percentage body fat and pubertal stage, neck circumference correlated with waist circumference, blood pressure, triglycerides and markers of insulin resistance in both genders. CONCLUSIONS: The results showed that the neck circumference is a useful tool for the detection of insulin resistance and changes in the indicators of metabolic syndrome in adolescents. The easiness of application and low cost of this measure may allow its use in Public Health services.

Biochemical, anthropometric and body composition indicators as predictors of hepatic steatosis in obese adolescents.

OBJECTIVE: To describe the prevalence of hepatic steatosis and to assess the performance of biochemical, anthropometric and body composition indicators for hepatic steatosis in obese teenagers. METHODS: Cross-sectional study including 79 adolecents aged from ten to 18 years old. Hepatic steatosis was diagnosed by abdominal ultrasound in case of moderate or intense hepatorenal contrast and/or a difference in the histogram ≥7 on the right kidney cortex. The insulin resistance was determined by the Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) index for values >3.16. Anthropometric and body composition indicators consisted of body mass index, body fat percentage, abdominal circumference and subcutaneous fat. Fasting glycemia and insulin, lipid profile and hepatic enzymes, such as aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase and alkaline phosphatase, were also evaluated. In order to assess the performance of these indicators in the diagnosis of hepatic steatosis in teenagers, a ROC curve analysis was applied. RESULTS: Hepatic steatosis was found in 20% of the patients and insulin resistance, in 29%. Gamma-glutamyltransferase and HOMA-IR were good indicators for predicting hepatic steatosis, with a cutoff of 1.06 times above the reference value for gamma-glutamyltransferase and 3.28 times for the HOMA-IR. The anthropometric indicators, the body fat percentage, the lipid profile, the glycemia and the aspartate aminotransferase did not present significant associations. CONCLUSIONS: Patients with high gamma-glutamyltransferase level and/or HOMA-IR should be submitted to abdominal ultrasound examination due to the increased chance of having hepatic steatosis.

Biochemical, anthropometric and body composition indicators as predictors of hepatic steatosis in obese adolescents / Indicadores bioquímicos, antropométricos y de composición corporal como predictores de la esteatosis hepática en adolescentes obesos / Indicadores bioquímicos, antropométricos e de composição corporal como preditores da esteatose hepática em adolescentes obesos

To describe the prevalence of hepatic steatosis and to assess the performance of biochemical, anthropometric and body composition indicators for hepatic steatosis in obese teenagers. METHODS: Cross-sectional study including 79 adolecents aged from ten to 18 years old. Hepatic steatosis was diagnosed by abdominal ultrasound in case of moderate or intense hepatorenal contrast and/or a difference in the histogram ≥7 on the right kidney cortex. The insulin resistance was determined by the Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) index for values >3.16. Anthropometric and body composition indicators consisted of body mass index, body fat percentage, abdominal circumference and subcutaneous fat. Fasting glycemia and insulin, lipid profile and hepatic enzymes, such as aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase and alkaline phosphatase, were also evaluated. In order to assess the performance of these indicators in the diagnosis of hepatic steatosis in teenagers, a ROC curve analysis was applied. RESULTS: Hepatic steatosis was found in 20% of the patients and insulin resistance, in 29%. Gamma-glutamyltransferase and HOMA-IR were good indicators for predicting hepatic steatosis, with a cutoff of 1.06 times above the reference value for gamma-glutamyltransferase and 3.28 times for the HOMA-IR. The anthropometric indicators, the body fat percentage, the lipid profile, the glycemia and the aspartate aminotransferase did not present significant associations. CONCLUSIONS: Patients with high gamma-glutamyltransferase level and/or HOMA-IR should be submitted to abdominal ultrasound examination due to the increased chance of having hepatic steatosis...

Describir la prevalencia de la esteatosis hepática y evaluar el desempeño de indicadores bioquímicos, antropométricos y de composición corporal para identificar la enfermedad en adolescentes obesos. MÉTODOS: Estudio transversal con 79 adolescentes de 10 a 18 años. Se diagnosticó la esteatosis hepática por ultrasonido abdominal en caso de contraste hepatorrenal moderado o intenso y/o diferencia en el histograma ≥7 con relación al córtex del riñón derecho. Se determinó la resistencia a la insulina por el índice Homeostasis Model Assessment-Insulin Resistence (HOMA-IR) para valores >3,16. Los indicadores antropométricos y de composición corporal fueron índice de masa corporal, porcentaje de grasa corporal, circunferencia abdominal y grasa subcutánea. Se dosificaron glucemia e insulina en ayuno, perfil lipídico y las encimas hepáticas aspartato aminotransferasa, alanina aminotransferasa, gama-glutamiltransferasa y fosfatasa alcalina. Se analizaron curvas ROC para evaluar el desempeño de los indicadores en identificar adolescentes con esteatosis hepática. RESULTADOS: La esteatosis hepática estuvo presente en el 20% de los pacientes y la resistencia a la insulina, en el 29%. La gama-glutamiltransferasa y el HOMA-IR se mostraron buenos indicadores para predecir la esteatosis hepática, con punto de corte de 1,06 veces por encima del valor de referencia para la gama-glutamiltransferasa y de 3,28 para el HOMA-IR. Los indicadores antropométricos, el porcentaje de grasa corporal, el perfil lipídico, la glucemia y la aspartato aminotransferasa no presentaron diferencias significantes. CONCLUSIONES: Pacientes con elevación de gama-glutamiltransferasa y/o HOMA-IR deben ser sometidos al examen de ultrasonido abdominal con gran probabilidad de obtenerse como resultado la esteatosis...

Descrever a prevalência da esteatose hepática e avaliar o desempenho de indicadores bioquímicos, antropométricos e de composição corporal para identificar a doença em adolescentes obesos. MÉTODOS: Estudo transversal com 79 adolescentes de dez a 18 anos. Diagnosticou-se a esteatose hepática por ultrassom abdominal em caso de contraste hepatorrenal moderado ou intenso e/ou diferença no histograma ≥7 em relação ao córtex do rim direito. Determinou-se a resistência à insulina pelo índice Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) para valores >3,16. Os indicadores antropométricos e de composição corporal foram: índice de massa corpórea, porcentagem de gordura corporal, circunferência abdominal e gordura subcutânea. Dosaram-se glicemia e insulina de jejum, perfil lipídico e enzimas hepáticas aspartato aminotransferase, alanina aminotransferase, gama-glutamiltransferase e fosfatase alcalina. Aplicou-se a curva ROC para avaliar o desempenho dos indicadores para identificar adolescentes com esteatose hepática. RESULTADOS: A esteatose hepática esteve presente em 20% dos pacientes e a resistência à insulina, em 29%. A gama-glutamiltransferase e o HOMA-IR mostraram-se bons indicadores para predizer a esteatose hepática, com ponto de corte de 1,06 vezes acima do valor de referência para a gama-glutamiltransferase e de 3,28 para o HOMA-IR. Os indicadores antropométricos, a porcentagem de gordura corporal, o perfil lipídico, a glicemia e a aspartato aminotransferase não apresentaram diferenças significantes. CONCLUSÕES: Pacientes com elevação de gama-glutamiltransferase e/ou HOMA-IR devem ser submetidos ao exame de ultrassom abdominal, havendo grande probabilidade de se obter como resultado a esteatose hepática...

Neck circumference as a new anthropometric indicator for prediction of insulin resistance and components of metabolic syndrome in adolescents: Brazilian Metabolic Syndrome Study / Circunferencia del cuello como un nuevo indicador antropométrico para predicción de resistencia a la insulina y componentes del síndrome metabólico en adolescentes: Brazilian Metabolic Syndrome Study - BRAMS / Circunferência do pescoço como um novo indicador antropométrico para predição de resistência à insulina e componentes da síndrome metabólica em adolescentes: Brazilian Metabolic Syndrome Study

To evaluate the correlation between neck circumference and insulin resistance and components of metabolic syndrome in adolescents with different adiposity levels and pubertal stages, as well as to determine the usefulness of neck circumference to predict insulin resistance in adolescents. METHODS: Cross-sectional study with 388 adolescents of both genders from ten to 19 years old. The adolescents underwent anthropometric and body composition assessment, including neck and waist circumferences, and biochemical evaluation. The pubertal stage was obtained by self-assessment, and the blood pressure, by auscultation. Insulin resistance was evaluated by the Homeostasis Model Assessment-Insulin Resistance. The correlation between two variables was evaluated by partial correlation coefficient adjusted for the percentage of body fat and pubertal stage. The performance of neck circumference to identify insulin resistance was tested by Receiver Operating Characteristic Curve. RESULTS: After the adjustment for percentage body fat and pubertal stage, neck circumference correlated with waist circumference, blood pressure, triglycerides and markers of insulin resistance in both genders. CONCLUSIONS: The results showed that the neck circumference is a useful tool for the detection of insulin resistance and changes in the indicators of metabolic syndrome in adolescents. The easiness of application and low cost of this measure may allow its use in Public Health services...

Evaluar la correlación de la circunferencia del cuello con resistencia a la insulina y con los componentes del síndrome metabólico en adolescentes con distintos niveles de adiposidad y estadios puberales, así como determinar la utilidad de la circunferencia del cuello como un parámetro en la predicción de resistencia a la insulina en adolescentes. MÉTODOS: Estudio transversal en el que se evaluó a 388 adolescentes de ambos sexos, de los 10 a los 19 años. Los adolescentes fueron sometidos a evaluación antropométrica y de composición corporal, incluyendo circunferencias del cuello y de la cintura, y la evaluación bioquímica. El estadio puberal se obtuvo mediante autoevaluación y la presión arterial, por el método de ausculta. Se evaluó la resistencia a la insulina por el Homeostasis Model Assessment-Insulin Resistence. La correlación entre dos variables fue evaluada con el coeficiente de corrrelación parcial ajustado para el porcentaje de grasa corporal y el estadio puberal. El desempeño de la circunferencia del cuello para identificar resistencia a la insulina fue evaluado por la Receiver Operating Characteristic Curve y se consideró p<0,05. RESULTADOS: Después del ajuste para el porcentaje de grasa corporal y estadio puberal, la circunferencia del cuello se correlacionó con la circunferencia de la cintura, presión arterial, triglicéridos y marcadores de resistencia a la insulina en ambos sexos. CONCLUSIONES: Los resultados demostraron que la circunferencia del cuello es una herramienta útil para detectar la resistencia a la insulina y la alteración en los indicadores de síndrome metabólico en adolescentes. La facilidad de aplicación y el bajo costo pueden hacer su uso viable en servicios de Salud Pública...

Avaliar a correlação da circunferência do pescoço com resistência à insulina e com os componentes da síndrome metabólica em adolescentes com diferentes níveis de adiposidade e estadios puberais, bem como determinar a utilidade da circunferência do pescoço como um parâmetro na predição de resistência à insulina em adolescentes. MÉTODOS: Estudo transversal no qual se avaliaram 388 adolescentes de ambos os sexos, de dez a 19 anos. Os adolescentes foram submetidos à avaliação antropométrica e de composição corporal, incluindo circunferências do pescoço e da cintura, e a avaliação bioquímica. O estadio puberal foi obtido por meio de autoavaliação e a pressão arterial, pelo método auscultatório. Analisou-se a resistência à insulina pelo Homeostasis Model Assessment-Insulin Resistance. A correlação entre duas variáveis foi verificada com o coeficiente de correlação parcial ajustado para o percentual de gordura corporal e o estadio puberal. O desempenho da circunferência do pescoço para identificar resistência à insulina foi testado pela Receiver Operating Characteristic Curve. RESULTADOS: Após ajuste para o percentual de gordura corporal e estadio puberal, a circunferência do pescoço correlacionou-se com circunferência da cintura, pressão arterial, triglicérides e marcadores de resistência à insulina em ambos os sexos. CONCLUSÕES: Os resultados demonstraram que a circunferência do pescoço é uma ferramenta útil para detectar a resistência à insulina e a alteração nos indicadores de síndrome metabólica em adolescentes. A facilidade de aplicação e o baixo custo podem viabilizar sua utilização...

Metabolic syndrome and insulin resistance in obese adolescents.

OBJECTIVE: To verify the prevalence of metabolic syndrome and insulin resistance in obese adolescents and its relationship with different body composition indicators. METHODS: A cross-sectional study comprising 79 adolescents aged ten to 18 years old. The assessed body composition indicators were: body mass index (BMI), body fat percentage, abdominal circumference, and subcutaneous fat. The metabolic syndrome was diagnosed according to the criteria proposed by Cook et al. The insulin resistance was determined by the Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) index for values above 3.16. The analysis of ROC curves was used to assess the BMI and the abdominal circumference, aiming to identify the subjects with metabolic syndrome and insulin resistance. The cutoff point corresponded to the percentage above the reference value used to diagnose obesity. RESULTS: The metabolic syndrome was diagnosed in 45.5% of the patients and insulin resistance, in 29.1%. Insulin resistance showed association with HDL-cholesterol (p=0.032) and with metabolic syndrome (p=0.006). All body composition indicators were correlated with insulin resistance (p<0.01). In relation to the cutoff point evaluation, the values of 23.5 and 36.3% above the BMI reference point allowed the identification of insulin resistance and metabolic syndrome. The best cutoff point for abdominal circumference to identify insulin resistance was 40%. CONCLUSIONS: All body composition indicators, HDL-cholesterol and metabolic syndrome showed correlation with insulin resistance. The BMI was the most effective anthropometric indicator to identify insulin resistance.

Metabolic syndrome and insulin resistance in obese adolescents / Sindrome metabolico y resistencia a la insulina en adolescentes obesos / Sindrome metabolica e resistencia a insulina em adolescentes obesos

Objective: To verify the prevalence of metabolic syndrome and insulin resistance in obese adolescents and its relationship with different body composition indicators. Methods: A cross-sectional study comprising 79 adolescents aged ten to 18 years old. The assessed body composition indicators were: body mass index (BMI), body fat percentage, abdominal circumference, and subcutaneous fat. The metabolic syndrome was diagnosed according to the criteria proposed by Cook et al. The insulin resistance was determined by the Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) index for values above 3.16. The analysis of ROC curves was used to assess the BMI and the abdominal circumference, aiming to identify the subjects with metabolic syndrome and insulin resistance. The cutoff point corresponded to the percentage above the reference value used to diagnose obesity. Results: The metabolic syndrome was diagnosed in 45.5% of the patients and insulin resistance, in 29.1%. Insulin resistance showed association with HDL-cholesterol (p=0.032) and with metabolic syndrome (p=0.006). All body composition indicators were correlated with insulin resistance (p<0.01). In relation to the cutoff point evaluation, the values of 23.5 and 36.3% above the BMI reference point allowed the identification of insulin resistance and metabolic syndrome. The best cutoff point for abdominal circumference to identify insulin resistance was 40%. Conclusions: All body composition indicators, HDL-cholesterol and metabolic syndrome showed correlation with insulin resistance. The BMI was the most effective anthropometric indicator to identify insulin resistance. .

Objetivo: Verificar la prevalencia del síndrome metabólico y de la resistencia a la insulina en adolescentes obesos y su relación con distintos indicadores de composición corporal. Métodos: Estudio transversal con 79 adolescentes de 10 a 18 años. Los indicadores de composición corporal fueron: índice de masa corporal (IMC), porcentaje de grasa corporal, circunferencia abdominal y grasa subcutánea. El síndrome metabólico fue diagnosticado conforme a los criterios de Cook et al. La resistencia a la insulina fue determinada por el índice de Homeostasis Model Assessment for Insulin Resistence (HOMA-IR) para valores superiores a 3,16. Se utilizó el análisis de curvas ROC para evaluar el IMC y la circunferencia abdominal, identificándose los individuos con resistencia a la insulina y síndrome metabólico. El punto de corte correspondió al porcentaje superior al valor de referencia para el diagnóstico de obesidad. Resultados: El síndrome metabólico fue diagnosticado en 45,5% de los pacientes y la resistencia a la insulina, en 29,1%. La resistencia a la insulina presentó asociación con el HDL-colesterol (p=0,032) y con el síndrome metabólico (p=0,006). Todos los indicadores de composición corporal evaluados presentaron correlación con la resistencia a la insulina (p<0,01). En la evaluación de los puntos de corte, los valores de 23,5 y 36,3% por encima del valor de referencia del IMC permitieron identificar la resistencia a la insulina y el síndrome metabólico. El mejor punto de corte de la circunferencia abdominal para identificar la resistencia a la insulina fue de 40%. Conclusiones: Todos los indicadores de composición corporal, el HDL-colesterol y el síndrome metabólico presentaron correlación con la resistencia a la insulina. El IMC se mostró el indicador ...

Objetivo: Verificar a prevalência da síndrome metabólica e da resistência à insulina em adolescentes obesos e sua relação com diferentes indicadores de composição corporal. Métodos: Estudo transversal com 79 adolescentes de dez a 18 anos. Os indicadores de composição corporal foram: índice de massa corpórea (IMC), porcentagem de gordura corporal, circunferência abdominal e gordura subcutânea. A síndrome metabólica foi diagnosticada segundo os critérios de Cook et al. A resistência à insulina foi determinada pelo índice de Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) para valores acima de 3,16. Utilizou-se a análise de curvas ROC para avaliar o IMC e a circunferência abdominal, identificando-se os indivíduos com resistência à insulina e síndrome metabólica. O ponto de corte correspondeu ao percentual acima do valor de referência para o diagnóstico de obesidade. Resultados: A síndrome metabólica foi diagnosticada em 45,5% dos pacientes e a resistência à insulina, em 29,1%. A resistência à insulina apresentou associação com o HDL-colesterol (p=0,032) e com a síndrome metabólica (p=0,006). Todos os indicadores de composição corporal avaliados apresentaram correlação com a resistência à insulina (p<0,01). Na avaliação dos pontos de corte, os valores de 23,5 e 36,3% acima do valor de referência do IMC permitiram identificar a resistência à insulina e a síndrome metabólica. O melhor ponto de corte da circunferência abdominal para identificar a resistência à insulina foi de 40%. Conclusões: Todos os indicadores de composição corporal, o HDL-colesterol e a síndrome metabólica apresentaram correlação ...