[Show abstract][Hide abstract] ABSTRACT: To compare the prevalence of metabolic abnormalities (MA) and metabolic syndrome (MS) assessed by different criteria among Brazilian adolescents.
Weighted prevalence of MA and MS were estimated using criteria adapted from the International Diabetes Federation (IDF), National Cholesterol Education Program, Adult Treatment Panel III (NCEP/ATP III), and the World Health Organization (WHO) in a probabilistic sample of 577 students aged 12-19.
The most prevalent MA was low concentration of HDL-C as per IDF (32.5%) and NCEP/ATP III (41.6%) criteria and hypertension as per the WHO's criterion (12.4%). Prevalence of MS using the NCEP/ATP III criterion (6.04%) was five times higher than the WHO's (1.1%) and the IDF's (1.6%) criteria. As expected, MS was significantly higher among overweight than among non-overweight adolescents.
Low prevalence of MS but high prevalence of some MA were found. These findings suggest that the diagnosis of MA is more relevant in clinical practice especially in overweight adolescents.
Preview · Article · Mar 2011 · Arquivos brasileiros de endocrinologia e metabologia
[Show abstract][Hide abstract] ABSTRACT: To compare the degree of concordance between plasma and capillary glucose for screening of diabetes mellitus in adolescents.
The plasma and capillary glucose of 119 adolescents aged 10-19 yr (36 males and 83 females) from public schools in Niterói, Rio de Janeiro State, Brazil, were verified after a 12-h fast. Agreement was assessed through kappa statistics (k), McNemar's chi-squared test, and the intraclass correlation coefficient (ICC). The paired Student's t-test for comparison of means, the approaches by Altman and Bland, and the survival-agreement plot were also applied.
Mean values of plasma glucose were 7.9 points higher than the capillary values (91.5 vs. 83.6 mg/dL, p < 0.001; ICC = 0.419). A regular agreement between the methods (k = 0.31, p < 0.001) for assessing proportions of adolescents with glycemia > or =100 mg/dL is observed. Using the strategy of adding 8 mg/dL to the capillary levels, the agreement improved (k = 0.46, p < 0.001) and a significant difference was not observed between the estimated prevalences (p = 0.815).
The results suggest a satisfactory agreement between the two methods when capillary glucose is corrected, and this may be a useful and low-cost tool for the epidemiologic investigation of diabetes mellitus prevalence in adolescents.
No preview · Article · Apr 2009 · Pediatric Diabetes
[Show abstract][Hide abstract] ABSTRACT: To determine the best cut-offs of body mass index for identifying alterations of blood lipids and glucose in adolescents.
A probabilistic sample including 577 adolescent students aged 12-19 years in 2003 (210 males and 367 females) from state public schools in the city of Niterói, Southeastern Brazil, was studied. The Receiver Operating Characteristic curve was used to identify the best age-adjusted BMI cut-off for predicting high levels of serum total cholesterol (> or =150 mg/dL), LDL-C (> or =100 mg/dL), serum triglycerides (> or =100 mg/dL), plasma glucose (> 100 mg/dL) and low levels of HDL-C (< 45 mg/dL). Four references were used to calculate sensitivity and specificity of BMI cut-offs: one Brazilian, one international and two American.
The most prevalent metabolic alterations (>50%) were: high total cholesterol and low HDL-C. BMI predicted high levels of triglycerides in males, high LDL-C in females, and high total cholesterol and the occurrence of three or more metabolic alterations in both males and females (areas under the curve range: 0.59 to 0.67), with low sensitivity (57%-66%) and low specificity (58%-66%). The best BMI cut-offs for this sample (20.3 kg/m(2) to 21.0 kg/m(2)) were lower than those proposed in the references studied.
Although BMI values lower than the International cut-offs were better predictor of some metabolic abnormalities in Brazilian adolescents, overall BMI is not a good predictor of these abnormalities in this population.
Preview · Article · Oct 2008 · Revista de saude publica
[Show abstract][Hide abstract] ABSTRACT: It was investigated the association of waist circumference (WC), abdominal circumference (AC), Waist-to-Hip ratio(WHR) and Waist-Height ratio (WHtR) adjusted by body mass index (BMI) and % body fat (BF) with metabolic syndrome components in a probabilistic sample of 610 adolescents aged 12-19 years (222 boys and 388 girls) from public schools of Niterói, Rio de Janeiro. Fasting glucose and lipids were assayed using automated enzymatic method and insulin was determined by radioimmuno assay. Systolic (SBP) and diastolic (DBP) blood pressure were measured using an automated recorder and % BF by electric bioimpedance. The association of the anthropometric measures with metabolic syndrome components was evaluated by multivariate linear regression adjusted according to the age, BMI or %BF. In boys, a positive association between WC (beta=1.03 p<0.01) and WHtR (beta= 2.33, p< 0.05; beta=2.12 and p< 0.01) with triglycerides was maintained after BMI and % BF adjusting, respectively. WC was associated with SBP after % BF adjusting both for boys (beta= 0.70 p<0.01) and girls (beta=0.68 p<0.01). In conclusion, WC was the measure of central body fat that presented the best association with components of metabolic syndrome in adolescents.
Preview · Article · Jun 2008 · Arquivos brasileiros de endocrinologia e metabologia
[Show abstract][Hide abstract] ABSTRACT: Avaliou-se a associação entre medidas antropométricas de localização de gordura central: circunferências da cintura (CC) e abdominal (CA) e as razões cintura/quadril (RCQ) e cintura/estatura (RCE), independente do percentual de gordura corporal (%GC) e índice de massa corporal (IMC), com os componentes da síndrome metabólica (SM) em uma amostra probabilística de 610 (222 meninos e 388 meninas) adolescentes de 12 a 19 anos de escolas públicas de Niterói, RJ. Foram avaliados glicose e perfil lipídico pelo método enzimático automatizado, insulina pela técnica de radioimunoensaio, %GC pela bioimpedância elétrica e a pressão arterial sistólica (PAS) e diastólica com manômetro digital. A associação entre as medidas antropométricas foi verificada por meio de regressão linear múltipla, com ajuste para IMC, %GC e idade. Nos meninos, a associação positiva entre CC (b = 1,03, p < 0,01) e RCE (b = 2,33, p < 0,05; b = 2,12 e p < 0,01) com triglicerídios foi mantida independente de IMC e % de GC, respectivamente. A CC se correlacionou com a PAS independente do %GC, tanto nos meninos (b = 0,70 p < 0,01) quanto nas meninas (b = 0,68 p < 0,01). Conclui-se que a CC foi a medida de gordura central que apresentou a melhor associação com os componentes da SM nos adolescentes.
Preview · Article · Jun 2008 · Arquivos Brasileiros de Endocrinologia & Metabologia
[Show abstract][Hide abstract] ABSTRACT: We assessed the association between insulin resistance, overweight and metabolic disorders in a probabilistic sample of 388, 12-19-year-old girls from public schools in Niterói, Rio de Janeiro State, Brazil. Insulin resistance was determined using Homeostatic Model Assessment-Insulin Resistance (HOMA-IR). Overweight and obesity were defined by the sex- and age-specific body mass index cut-offs recommended by the International Obesity Task Force. Metabolic syndrome (MS) was identified by the presence of at least three of the following factors: fasting glucose >or=100mg/dL, triglycerides >130 mg/dL, LDL-C >or=110 mg/dL, HDL-C <35 mg/dL and overweight. The combined prevalence of obesity (2.9%) and overweight was 14.2%. The average HOMA-IR level was 2.24 (95% confidence interval=1.40-3.10) in the overweight group and 1.91 (95% CI=1.32-2.50) in the non-overweight one, and MS prevalence was 20 times higher in the first group (21.4 and 0.1%). MS prevalence in the overweight group was 6.3 times higher in adolescents above the 66th percentile of HOMA-IR (55.9%) than those under the 33rd percentile (8.9%). Brazilian overweight girls with higher insulin resistance had high risk of developing MS. Therefore, prevention should occur at an early age to impair the evolution of this process.
No preview · Article · Dec 2006 · Diabetes Research and Clinical Practice
[Show abstract][Hide abstract] ABSTRACT: This study evaluates the accuracy of cutoff points in the body mass index (BMI) for identifying adolescents with overweight, compared to the percentage of body fat, estimated by electric bioimpediance, in a probabilistic sample of 610 adolescents from 12 to 19 years of age (222 boys and 388 girls) enrolled in public schools in Niterói, Rio de Janeiro, Brazil. ROC was used to evaluate the sensitivity and specificity of BMI cutoffs from one Brazilian, two North American, and one international reference. The cutoff points in the study sample were lower than the other references, with 76% to 95% sensitivity and 75% to 95% specificity. The Brazilian cutoff points were also more sensitive (53% to 100%) as compared to the other references (40% to 86%). The international parameter showed better sensitivity for older adolescents, and the Northern American references for younger adolescents. BMI was a good proxy for adiposity, but cutoff points from other population references should be used with caution, since they can lead to classification errors in adolescents with overweight.