RESUMO
AIM: We aimed to evaluate associations between serum ferritin and transferrin and variables related to the metabolic syndrome (MetS) in children. METHODS: Cross-sectional and longitudinal study in prepubertal children (n = 832) aged 3-14 years. A subset (n = 203) were re-examined after a mean follow-up of 3.7 ± 0.8 years[range 2-6]. Outcomes were MetS and MetS components scores, glycosylated haemoglobin (HbA1c), and their follow-up change. RESULTS: Children with low ferritin had increased HbA1c Z scores (ANCOVA, P = 0.003). Ferritin was inversely associated with glycaemia [fully adjusted ß (95% confidence interval): -2.35(-4.36 to -0.34)]. Transferrin was associated with diastolic blood pressure [ß: 0.02(0.01-0.04)] and log-HOMA-IR [ß:0.001(0.0005-0.002)]. MetS risk score worsened during follow-up in children with the lowest baseline ferritin levels. In contrast, at baseline ferritin was positively associated with all (except glycaemia) the MetS-related variables but adjustments for inflammatory, hepatic function, and body mass markers attenuated those associations (P > 0.05). CONCLUSIONS: Lower iron status was independently associated with glycaemic markers and MetS in children, whereas higher ferritin levels were related to other cardiometabolic risk markers under the influence of inflammation, hepatic injury and body mass. Research is required to study whether this mixed pattern is part of an early risk or would be explained by a normal transition during growth and development.
Assuntos
Doenças Cardiovasculares , Resistência à Insulina , Síndrome Metabólica , Humanos , Criança , Ferro/metabolismo , Hemoglobinas Glicadas , Estudos Longitudinais , Estudos Transversais , Biomarcadores , Síndrome Metabólica/epidemiologia , Ferritinas , Transferrina/metabolismo , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Índice de Massa CorporalRESUMO
OBJECTIVE: The clinical utility of screening for pediatric metabolic syndrome (MetS) in children and adolescents is still controversial. We examined the performance of pediatric MetS vs. clustering of cardiovascular risk factors (which are the components of MetS) for predicting high carotid intima-media thickness (cIMT) in children and adolescents. METHODS: Participants included 2427 children and adolescents aged 6-17 years from population-based studies in three countries (Brazil, China and Italy). Pediatric MetS was defined using either the modified National Cholesterol Education Program Adult Treatment Panel III criteria or the modified International Diabetes Federation criteria. Clustering of cardiovascular risk factors was calculated as the sum of five components of MetS (i.e. central obesity, elevated blood pressure, elevated triglycerides, reduced HDL-cholesterol and elevated fasting blood glucose). High cIMT was defined as cIMT at least 95th percentile values for sex and age developed from European children. RESULTS: Presence of one, two or at least three cardiovascular risk factors (using the National Cholesterol Education Program Adult Treatment Panel III criteria), as compared with none, was associated with gradually increasing odds of high cIMT [odds ratios (95% confidence intervals): 1.60 (1.29-1.99), 2.89 (2.21-3.78) and 4.24 (2.81-6.39), respectively]. High cIMT was also associated with presence (vs. absence) of MetS (odds ratioâ=â2.88, 95% confidence intervalâ=â1.95-4.26). However, clustering of cardiovascular risk factors predicted high cIMT markedly better than MetS (area under the curve of 0.66 vs. 0.54, respectively). Findings were similar using the International Diabetes Federation criteria for pediatric MetS. CONCLUSION: In children and adolescents, a graded score based on five cardiovascular risk factors (used to define MetS) predicted high cIMT markedly better than MetS. These findings do not support the clinical utility of MetS for screening youth at increased cardiovascular risk, as expressed in this study by high cIMT.
Assuntos
Doenças Cardiovasculares/etiologia , Espessura Intima-Media Carotídea , Síndrome Metabólica/complicações , Obesidade Infantil/complicações , Adolescente , Glicemia/metabolismo , Brasil , Doenças Cardiovasculares/sangue , Criança , China , Colesterol/sangue , Análise por Conglomerados , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Hipertensão/complicações , Itália , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/fisiopatologia , Obesidade Infantil/fisiopatologia , Triglicerídeos/sangueRESUMO
OBJECTIVE: This study aimed to evaluate the association of metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO) with iron status markers in prepubertal children. METHODS: Three hundred twelve prepubertal children with overweight and obesity from a pediatric general Spanish population were evaluated. MHO and MUO were defined as obesity with the absence or presence of metabolic syndrome components. Phenotypes of metabolically healthy overweight including obesity (MHOV) and metabolically unhealthy overweight including obesity (MUOV) were also studied and defined using the same criteria. Serum ferritin, transferrin, and blood hemoglobin levels were evaluated. RESULTS: Prevalence rates of MHOV and MHO were 35% (n = 111/312) and 27.1% (n = 42/155), respectively. Ferritin and hemoglobin levels were higher in children with MUOV versus MHOV (P < 0.05). MUO was positively associated with ferritin (beta [95% CI] = 0.43 [0.05 to 0.81]) and hemoglobin levels (0.43 [0.05 to 0.81]). These associations remained significant independently of age, sex, C-reactive protein, physical activity, and BMI/waist z scores in bivariate linear regression models. In multivariable models, transaminase levels attenuated the association of MUO with ferritin and hemoglobin levels (P > 0.05). CONCLUSIONS: MUOV and MUO are associated with higher ferritin and hemoglobin levels in prepubertal children affected by overweight and obesity. Increased circulating ferritin in MUO might be influenced by liver injury.
Assuntos
Ferro/sangue , Obesidade Infantil/sangue , Maturidade Sexual/fisiologia , Adolescente , Proteína C-Reativa/metabolismo , Criança , Pré-Escolar , Estudos Transversais , Exercício Físico , Feminino , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/complicações , Sobrepeso/sangue , Sobrepeso/complicações , Obesidade Infantil/complicações , Fenótipo , Projetos Piloto , Puberdade/fisiologiaRESUMO
OBJECTIVE: It has been argued that metabolically healthy obesity (MHO) does not increase cardiovascular disease (CVD) risk. This study examines the association of MHO with carotid intima-media thickness (cIMT), a proxy of CVD risk, in children and adolescents. RESEARCH DESIGN AND METHODS: Data were available for 3,497 children and adolescents aged 6-17 years from five population-based cross-sectional studies in Brazil, China, Greece, Italy, and Spain. Weight status categories (normal, overweight, and obese) were defined using BMI cutoffs from the International Obesity Task Force. Metabolic status (defined as "healthy" [no risk factors] or "unhealthy" [one or more risk factors]) was based on four CVD risk factors: elevated blood pressure, elevated triglyceride levels, reduced HDL cholesterol, and elevated fasting glucose. High cIMT was defined as cIMT ≥90th percentile for sex, age, and study population. Logistic regression model was used to examine the association of weight and metabolic status with high cIMT, with adjustment for sex, age, race/ethnicity, and study center. RESULTS: In comparison with metabolically healthy normal weight, odds ratios (ORs) for high cIMT were 2.29 (95% CI 1.58-3.32) for metabolically healthy overweight and 3.91 (2.46-6.21) for MHO. ORs for high cIMT were 1.44 (1.03-2.02) for unhealthy normal weight, 3.49 (2.51-4.85) for unhealthy overweight, and 6.96 (5.05-9.61) for unhealthy obesity. CONCLUSIONS: Among children and adolescents, cIMT was higher for both MHO and metabolically healthy overweight compared with metabolically healthy normal weight. Our findings reinforce the need for weight control in children and adolescents irrespective of their metabolic status.
Assuntos
Espessura Intima-Media Carotídea , Obesidade Metabolicamente Benigna/epidemiologia , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Adolescente , Pressão Sanguínea , Brasil , Criança , China , Estudos Transversais , Feminino , Seguimentos , Grécia , Nível de Saúde , Humanos , Itália , Modelos Logísticos , Masculino , Obesidade Metabolicamente Benigna/sangue , Sobrepeso/sangue , Obesidade Infantil/sangue , Prevalência , Fatores de Risco , EspanhaRESUMO
A longitudinal study with dual x-ray absorptiometry disclosed that infants born large for gestational age from mothers without diabetes mellitus and without excessive gestational weight gain tend to be long with increased adipose tissue as newborns and tall and lean as toddlers.
Assuntos
Peso ao Nascer , Composição Corporal , Macrossomia Fetal/fisiopatologia , Absorciometria de Fóton , Diabetes Mellitus , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Mães , Aumento de PesoRESUMO
OBJECTIVE: According to the concept of adipose tissue expandability, the vascular complications of obesity are related less to the amount of stored fat than to the low-grade inflammation that excess fat storage may elicit. We tested this concept in 7-year-old children by assessing whether carotid intima-media thickness (cIMT) is related to obesity measures or to circulating highly sensitive C-reactive protein (hsCRP), as a marker of low-grade inflammation. STUDY DESIGN: The study group comprised 135 asymptomatic Caucasian children (72 girls and 63 boys; mean age, 7.1±1.1 years) with normal height and weight distributions. Relationships were assessed among cIMT, hsCRP, obesity measures (ie, body mass index [BMI], total fat by bioelectric impedance, and visceral fat by ultrasound), insulin resistance (by the homeostasis model assessment for insulin resistance), and fasting serum lipid levels. RESULTS: cIMT was correlated with hsCRP, but not with BMI or body fat; the regression coefficients between cIMT and hsCRP (adjusted for age, sex, BMI, body fat, and serum lipid levels) were fairly similar across all BMI categories (ß=0.370-0.411; all P<.001 to<.0001). Serum hsCRP increased with increasing BMI, total fat, and visceral fat (all P<.001). CONCLUSION: At age 7 years, cIMT is already associated with low-grade inflammation, as measured by hsCRP, but not with BMI or body fat. These findings imply that public health strategies aimed at early prevention of cardiovascular disease may need to target low-grade inflammation rather than only BMI or adiposity.
Assuntos
Tecido Adiposo/diagnóstico por imagem , Proteína C-Reativa/imunologia , Proteína C-Reativa/metabolismo , Espessura Intima-Media Carotídea , Fatores Etários , Biomarcadores/sangue , Índice de Massa Corporal , Peso Corporal , Criança , Feminino , Humanos , Inflamação/sangue , MasculinoRESUMO
Breast-fed infants born small-for-gestational-age (SGA) (n = 28) were found to develop lower adiposity across early infancy, when compared with appropriate-for-gestational age infants (n = 46). The SGA infants were also found to have 2-fold higher (P < .001) levels of circulating leptin at 4 months. This paradoxical hyperleptinemia in early infancy may contribute to a program that produces a process from fetal underweight to adult overweight.
Assuntos
Adiposidade/fisiologia , Aleitamento Materno , Recém-Nascido Pequeno para a Idade Gestacional/fisiologia , Leptina/sangue , Composição Corporal , Feminino , Seguimentos , Humanos , Recém-Nascido , MasculinoRESUMO
OBJECTIVE: Puberty is part of a critical window in which adiposity and its correlates can be fine-tuned toward reproduction, which implies that puberty provides an opportunity to reprogram a misprogramming that occurred in early life. We tested this hypothesis in low-birthweight (LBW) girls with precocious pubarche (PP), who are at risk for hyperinsulinemic body adiposity during and beyond puberty. STUDY DESIGN: LBW girls with PP (n = 38; mean age 8 years) were randomized to remain untreated or to receive metformin across puberty (425 mg/d for 2 years, then 850 mg/d for 2 years); subsequently, all girls were monitored for 1 year without intervention. Here we report on the latter year. RESULTS: The benefits of metformin were mostly maintained during the posttreatment year so that, after 5 years, metformin therapy was associated with more lean mass; with less total, visceral, and hepatic fat; with lower circulating levels of androgens and leptin; and with elevated levels of high-molecular-weight adiponectin and undercarboxylated osteocalcin. CONCLUSION: In LBW girls with PP, pubertal metformin therapy was followed by a favorable adipokine profile and by a reduction of total, visceral, and hepatic adiposity beyond puberty.
Assuntos
Adiposidade/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Adolescente , Peso Corporal/efeitos dos fármacos , Criança , Comorbidade , Feminino , Seguimentos , Humanos , Hiperinsulinismo/epidemiologia , Hipoglicemiantes/uso terapêutico , Recém-Nascido de Baixo Peso , Recém-Nascido , Gordura Intra-Abdominal/efeitos dos fármacos , Leptina/sangue , Fígado/patologia , Imageamento por Ressonância Magnética , Metformina/uso terapêutico , Puberdade Precoce/epidemiologia , Puberdade Precoce/fisiopatologiaRESUMO
Longitudinal data collected from children ages 2 until 6 years, who were born appropriate-for-gestational-age or small-for-gestational-age, indicate that the latter have a normal body fat fraction and normal high-molecular-weight adiponectinemia at age 2 years and that they accumulate excess adipose tissue and have low adiponectin levels by age 4 to 6 years.