Leptin/adiponectin ratio as a prognostic factor for increased weight gain in girls with central precocious puberty.

Objective: To determine if the leptin, adiponectin, and leptin/adiponectin ratio (LAR) can predict weight gain at the end of GnRH analogs (GnRHa) treatment in girls with central precocious puberty (CPP). Material and methods: Study design: prospective cohort. Serum levels of leptin and adiponectin were determined at diagnosis of CPP. Anthropometry was performed at diagnosis of CPP and every six-months, until treatment with GnRHa was discontinued and they presented menarche. Patients were divided according to BMI<94 and BMI>95 percentile at diagnosis of CPP. The outcome was the increased in weight gain (e.g., from normal weight to overweight) at the end of follow-up. Statistical analysis: repeated measures ANOVA test and Student's t-test were used to compare groups. Logistic regression analysis was used to evaluate the association of leptin and adiponectin levels, as well as LAR values with increased weight gain. Results: Fifty-six CPP patients were studied, 18 had BMI >95 percentile and 38 BMI <94 percentile. Of the 18 patients who initially had BMI >95th, two patients went from obesity to overweight, while among the 38 patients who started with BMI <94th, 21 (55.2%) increased their weight gain at the end of follow-up. This last group had higher leptin levels (8.99 ± 0.6 vs 6.14 ± 0.8, p=0.005) and higher LAR values compared to those who remained in the same weight (1.3 ± 0.5 vs 0.96 ± 0.56, p=0.01). In the logistic regression analysis, it was found that higher leptin levels and higher LAR values were associated with increased weight gain (RR 1.31, 95%CI 1.03-1.66, RR 4.86, 95%CI 1.10-21.51, respectively), regardless of birth weight, pubertal stage, age, and bone/chronological age ratio. Conclusions: In patients with CPP, leptin levels and higher LAR values appear to be associated with significantly greater weight gain during GhRHa treatment, particularly in girls starting with BMI < 94 percentile.

Leptin receptor and prolactin in pubertal disorders and chronic kidney disease.

BACKGROUND: Knowledge of chronic kidney disease (CKD) with pubertal disorders (PD) in adolescent boys is limited as few studies have explored this disorder. This study aimed to identify the usefulness of assessing hormonal parameters in male adolescents with CKD and their correlation with PD in a 12-month follow-up period. METHODS: A prospective cohort study was conducted among male adolescents with CKD (stages IV and V). Data regarding the age at puberty onset were collected from the patients' clinical records and through interview. The patients were followed up for 12 months during their pubertal development. At the beginning, routine hormonal profile tests were performed to examine the patients' thyroid profile, prolactin levels, luteinizing hormone, follicle-stimulating hormone, testosterone, leptin, and receptor leptin. The hormonal profiles of patients with and without PD were compared. Comparisons between the groups were performed using the Student t-test and Fisher's exact tests. Logistic regression analysis was also performed. RESULTS: Data of 64 patients (26/64 with PD) were analyzed. The median age was 15 years and the median time for CKD evolution was 11 months. No differences between groups were noted in the general or biochemical characteristics of the patients. The hormonal parameters, prolactin levels were higher and the free leptin and free thyroxine levels were lower in patients with PD. Leptin receptor levels of >0.90 ng/mL (risk ratio [RR], 8.6; P = 0.004) and hyperprolactinemia (RR, 21.3; P = 0.049) were the risk factors for PD. CONCLUSIONS: Leptin receptor levels of >0.90 ng/mL and hyperprolactinemia are associated with the development of PD in male adolescents with CKD.

The leptin/adiponectin ratio as prognostic marker for dyslipidemia during 1 year of follow-up in pediatric patients receiving kidney replacement therapy.

Introduction: Background: leptin and adiponectin are associated with cardiovascular disease in chronic kidney disease (CKD) patients and could be useful prognostic factors. Objectives. to explore the usefulness of the leptin/adiponectin ratio (LAR) to predict the presence or worsening of dyslipidemia during 1 year of follow-up in children receiving kidney replacement therapy (KRT). Material and methods: a prospective cohort study was performed. Pediatric KRT patients aged between 8 and 17 years who were undergoing hemodialysis or peritoneal dialysis were included. At enrollment, the lipid profile, adiponectin and leptin levels, and somatometric measurements, including body fat percentage, were determined. At the one-year follow-up, the lipid profile was reassessed. Results: of the 70 patients included, the median age was 13 years, and there was no sex predominance (52.8 % males). At the end of follow-up, the patients were divided into three groups: those without dyslipidemia (WOD), those who developed or experienced worsening of their dyslipidemia (DWD) and those with persistent dyslipidemia (PD). A LAR > 0.85 (OR, 16.7) and body fat percentage (OR, 1.46) were associated with an increased risk of PD and DWD at 12 months, independently of urea level, BMI Z-score, benzafibrate treatment, CKD progression time, and replacement treatment. Conclusions: a LAR > 0.85 and fat body percentage at the beginning of follow-up were strongly associated with the presence, persistence or worsening of dyslipidemia at the 12-month follow-up in children with KRT.

Introducción: Antecedentes: la leptina y la adiponectina se asocian con enfermedad cardiovascular en los pacientes con enfermedad renal crónica (ERC) y podrían ser factores pronósticos útiles. Objetivos: explorar la utilidad del cociente leptina/adiponectina (LAR) para predecir la presencia o empeoramiento de la dislipidemia durante 1 año de seguimiento en niños que reciben terapia de reemplazo renal (TRR). Material y métodos: se realizó un estudio de cohortes prospectivo. Se incluyeron pacientes pediátricos con TRR de entre 8 y 17 años que estaban en hemodiálisis o diálisis peritoneal. Al inicio del estudio se determinaron el perfil lipídico, los niveles de adiponectina y leptina, y las mediciones somatométricas, incluido el porcentaje de grasa corporal. En el seguimiento de un año, se reevaluó el perfil de lípidos. Resultados: de los 70 pacientes incluidos, la mediana de edad fue de 13 años y no hubo predominio de sexo (52,8 % de varones). Al final del seguimiento, los pacientes se dividieron en tres grupos: aquellos sin dislipidemia (SD), aquellos que desarrollaron o experimentaron un empeoramiento de su dislipidemia (ED) y aquellos con dislipidemia persistente (PD). Un LAR > 0,85 (OR: 16,7) y el porcentaje de grasa corporal (OR: 1,46) se asociaron con un mayor riesgo de ED y PD a los 12 meses, independientemente del nivel de urea, la puntuación Z del IMC, el tratamiento con benzafibrato, el tiempo de progresión de la ERC y el tratamiento de reemplazo. Conclusiones: un LAR > 0,85 y el porcentaje de grasa corporal al inicio del seguimiento se asociaron fuertemente con la presencia, persistencia o empeoramiento de la dislipidemia a los 12 meses de seguimiento en niños con TRR.

Altered cardiometabolic profile in girls with central precocious puberty and adipokines: A propensity score matching analysis.

OBJECTIVE: To compare cardiometabolic factors and adipokines between patients with recently diagnosed CPP and controls without CPP, paired by BMI Z scores (BMIz) and classified into girls with adequate nutritional status and girls who are overweight or obese. METHODS: This cross-sectional study was performed from January 2012 to May 2015 at two tertiary care pediatric centers in Mexico City. We included female patients with idiopathic CPP without other chronic pathology and healthy controls. Patients were divided into groups, BMI < 85th and BMI ≥ 85th percentile, according to 2000 CDC Growth Charts. Anthropometric data and fasting plasma concentrations of lipids, glucose, insulin, and leptin were assessed. RESULTS: There were 73 patients with CPP and 82 without CPP. Sixty-six patients were matched between the groups; no significant difference was noted between the groups according to zBMI. However, differences in the bone/chronological age relationship, birth weight and proportions in different Tanner stages were observed. Among girls with normal BMI, the percentage of body fat (24.6% vs 18.9%, p < 0.001), serum triglycerides (102.9 vs 54.3 mg/dl, p < 0.001), leptin (7.46 vs 5.4 ng/ml, p = 0.010) and free leptin (0.44 vs 0.29 ng/ml, p = 0.044) were higher in those with CPP; additionally, girls with CPP presented a higher proportion of hypertriglyceridemia. In the overweight/obese group, adiponectin levels were lower in girls with CPP (6.23 vs 7.28 pg/ml, p = 0.011). CONCLUSIONS: Girls with CPP and normal BMI at diagnosis had a worse cardiometabolic profile, as reflected by higher levels of free leptin, and higher proportion of hypertriglyceridemia than girls without CPP.

Hyperprolactinemia as a prognostic factor for menstrual disorders in female adolescents with advanced chronic kidney disease.

BACKGROUND: In adolescents with chronic kidney disease (CKD), menstrual disorders (MD) are common, which can make the management of CKD difficult and can sometimes delay renal transplantation. This study aimed to identify the usefulness of hormonal measurements in adolescents with CKD and their relationships with MD during a 1-year follow-up. METHODS: A prospective cohort study was designed. Adolescents with CKD stages IV and V were included. Through clinical files and via interview, the ages at puberty onset, menarche and the date of last menstruation were identified. A 1-year follow-up was conducted over a menstrual cycle calendar. At the beginning of follow-up, routine hormonal profiles (thyroid profiles, prolactin, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estradiol) were assessed. We compared the hormonal profiles of the patients with and without MD (wMD vs. woMD). Comparisons between groups were made by Wilcoxon and Fisher's tests. Logistic regression analysis was used. RESULTS: Fifty-seven patients, including 30 patients classified as wMD, were analyzed. The median age was 15 years, and the median time of CKD evolution was 18 months. There were no differences in general and biochemical characteristics between patients wMD and woMD. In terms of hormonal measurements, the levels of thyroid-stimulating hormone (TSH) and prolactin were higher in the wMD patients. A prolactin level ≥ 36.8 ng/ml was a risk factor for presenting with MD (RR 34.4, p = 0.002). CONCLUSIONS: Hyperprolactinemia is correlated with MD in adolescents with CKD.

Resistin/Uric Acid Index as a Prognostic Factor in Adolescents with Obesity after Lifestyle Intervention.

OBJECTIVE: To evaluate the resistin/uric acid index as a prognostic factor associated with body mass index (BMI) z-score change after 1 year of lifestyle interventions for obesity. STUDY DESIGN: In this prospective cohort study, we included 102 adolescents with overweight or obesity (BMI ≥85th percentile). Weight and height were measured at the start of the lifestyle change intervention and 12 months later. Serum levels of resistin and uric acid were quantified at the beginning of the intervention. The intervention consisted of nutrition education, exercise, and physical activity promotion. RESULTS: The sample included 54 girls and 48 boys; the median age was 11 years (range 10-16 years). The BMI z-score decreased during follow-up (median BMI z-score at baseline was 1.81 vs 1.70 after 1 year, P < .001). The resistin/uric acid index was positively correlated with BMI z-score change (r = 0.27, P < .01). In the linear regression analysis, the resistin/uric acid index was significantly associated with BMI z-score modification at the 12-month follow-up (ß = 0.17; 95% CI 0.08-0.26; P < .01). CONCLUSIONS: The resistin/uric acid index can be considered a prognostic factor for identifying adolescents with overweight or obesity with a greater probability of improving their BMI. This index could help establish different interventions for adolescents with overweight and obesity; however, additional studies are needed to confirm the usefulness of this index.

Resistin levels are not associated with obesity in central precocious puberty.

OBJECTIVE: To compare serum resistin concentrations between prepubertal girls with a BMI > 85th percentile and girls with precocious puberty (CPP) who have and have not undergone GnRH analog treatment. PATIENTS AND METHODS: This is a cross-sectional study in girls with a BMI > 85th percentile and a median age of 8 years. We included 31 girls with CPP who did not receive treatment (CPPoT), 23 girls with CPP who were treated with leuprolide (CPPT), 22 prepubertal girls and 24 pubertal girls. Anthropometric data and the fasting plasma concentrations of lipids, glucose, insulin, and resistin were measured. RESULTS: The z-BMI scores were similar among the groups (p = 0.344), and body fat percentage (BF%) was similar among CPPT, CPPoT and prepubertal girls (p = 0.151). Resistin and insulin levels were lower in girls with CPP (CPPT and CPPoT) than in prepubertal and pubertal girls (median resistin level: CPPT 11.8 pg/ml vs CPPoT 11 pg/ml vs prepubertal 16 pg/ml vs pubertal 16 pg/ml, p = 0.001; median insulin level: CPPT 10.7 µUI/mL vs CPPoT 10.2 µUI/mL vs prepubertal 14.4 µUI/mL vs pubertal 32 µUI/mL p = 0.02). ANCOVA analysis, after adjustments for pubertal stage, BF% and z-BMI, showed that CPP modifies resistin levels (F = 31.4; p = 0.0001) independently of these parameters (p < 0.05). CONCLUSIONS: In the group of girls with overweight or obesity, the resistin level was lower in girls with CPP than in prepubertal and pubertal girls. More studies are needed to understand the role of resistin in CPP patients.

Association of leptin with cardiometabolic factors in schoolchildren and adolescents with congenital adrenal hyperplasia. / Asociación de leptina con factores cardiometabólicos en escolares y adolescentes con hiperplasia suprarrenal congénita.

Introduction: In congenital adrenal hyperplasia (CAH), obesity, hyperinsulinemia and leptin levels are increased. Objective: To identify the frequency of cardiometabolic risk factors (CRF) in children and adolescents with CAH and to explore the relationship with leptin levels. Method: Cross-sectional study of 40 patients who underwent anthropometric measurements and had fasting glucose, insulin, triglycerides, 17-hidroxyprogesterone, leptin, HDL and LDL-cholesterol assessed. The patients were classified according to the number of CRFs, and leptin levels were analyzed with the Kruskal-Wallis test. Pearson's correlation was applied between leptin, body mass index (BMI) z-score and body fat percentage. Results: Fifty percent of the patients had obesity and overweight, 59% had hypertriglyceridemia, 40%, hypoalphalipoproteinemia, 27.5%, high LDL-cholesterol and 22.5% insulin resistance. There was positive correlation between leptin and body fat percentage (r = 0.64), BMI z-score (r = 0.55) and the number of CRFs (r = 0.65). In the obesity-adjusted multivariate analysis, leptin levels were associated with the number of CRFs. Conclusion: CAH had a high frequency of CRFs and leptin appeared to be associated with a more adverse cardiometabolic profile in subjects with obesity and overweight.

Introducción: En la hiperplasia suprarrenal congénita (HSC), la obesidad, la hiperinsulinemia y los niveles de leptina se encuentran incrementados. Objetivo: Identificar la frecuencia de los factores de riesgo cardiometabólico (FRC) en niños y adolescentes con HSC y explorar la relación con los niveles de leptina. Método: Estudio transversal de 40 pacientes a quienes se realizó somatometría y evaluación de glucosa, insulina, triglicéridos, 17-hidroxiprogesterona, leptina, colesterol HDL y LDL en ayuno. Los pacientes fueron clasificados por el número de FRC y se analizaron los niveles de leptina con Kruskal-Wallis. Se aplicó correlación de Pearson entre la leptina, puntuación Z del índice de masa corporal (zIMC) y porcentaje de grasa corporal. Resultados: 50 % de los pacientes presentó obesidad y sobrepeso, 59 % hipertrigliceridemia, 40 % hipoalfalipoproteinemia, 27.5 % colesterol LDL alto y 22.5 % resistencia a la insulina. Hubo correlación positiva entre leptina y porcentaje de grasa corporal (r = 0.64), el zIMC (r = 0.55) y el número de FRC (r = 0.65). En el análisis multivariado ajustado por obesidad, los niveles de leptina se asociaron con el número de FRC. Conclusión: La HSC tuvo alta frecuencia de FRC y al parecer la leptina se asoció con perfil cardiometabólico más adverso en sujetos con obesidad y sobrepeso.

RELATIONSHIP BETWEEN SERUM LEPTIN LEVELS AND WEIGHT GAIN IN GIRLS WITH CENTRAL PRECOCIOUS PUBERTY AT 1-YEAR FOLLOW-UP.

OBJECTIVE: Patients with central precocious puberty (CPP) may have increased serum leptin levels; however, it is not well known whether this increase differs between patients with and without obesity. Our objectives were to describe the changes in serum leptin in girls with CPP in the first 12 months after diagnosis based on body mass index (BMI) and to explore whether serum leptin level at CPP diagnosis is related to BMI z-score (BMIz) after a 1-year follow-up. METHODS: A prospective cohort study was performed. We included 42 girls with idiopathic CPP in Tanner stages II and III. Anthropometric measurements were performed, and serum leptin was measured at study initiation and after 12 months. Patients were stratified according to BMI category (30 with a BMI in the <94th percentile and 12 with a BMI in the >95th percentile). Study variables were compared. Correlations among leptin, BMIz, and body fat were assessed. RESULTS: Leptin increased gradually during the first year of treatment. In girls with a BMI in the <94th percentile at diagnosis, body fat percentage increased gradually during the first year of follow-up. CONCLUSION: Girls with a BMI in the <94th percentile have a greater risk of weight increase. Leptin level >10.5 ng/dL at diagnosis is a risk factor for weight gain after 1 year. ABBREVIATIONS: BMI = body mass index BMIz = BMI z-score CPP = central precocious puberty GnRHa = gonadotropin-releasing hormone analogue.

Relationship of receptors of adipokines with hypertension and obesity. Murine model

Background: The aim of this paper is to investigated the contribution of adipose tissue thought the adipokines and kidney failure (KF) Methods: In male rats were fed with a standard lab diet (C) or a hypercaloric diet including 30% sucrose; obese group (Ob) and obese with kidney failure group (Ob/KF). We evaluated the changes of adipokines under conditions of obesity and KF, using 5/6 surgery to induce vascular injury. The anterior and media branches of the left kidney artery were tied together, leaving the posterior branch viable to enable the kidney to function. The right kidney was removed. Results: A 90% survival rate of the animals was achieved due to special care taken. Kidney function progressively decreased after surgery. Compared with the control group, in the other two groups (Ob and Ob/KF) the level of leptin increased and that of adiponectin decreased (p < 0.01). Post-surgery increases were observed in blood pressure, lipids, creatinine and insulin (p < 0.01). Conclusion: This model is proposed for the study pathophysiological mechanisms that lead to obesity and complications of kidney or cardiovascular function.

Introducción: El objetivo de este trabajo es investigar la contribución del tejido adiposo y las adipocinas y la insuficiencia renal (KF). Métodos: Ratas machos se alimentaron con una dieta estándar de laboratorio (C) o una dieta hipercalórica incluyendo 30% de sacarosa; Grupo obeso (Ob) y obeso con grupo de insuficiencia renal (Ob/KF). Se evaluaron los cambios de adipocinas en condiciones de obesidad y KF, utilizando cirugía 5/6 para inducir lesión vascular. Las ramas anterior y media de la arteria renal izquierda fueron unidas, dejando la rama posterior viable para permitir sobreviviencia y función renal. El riñón derecho fue removido. Resultados: Se logró una tasa de supervivencia del 90% de los animales debido a un cuidado especial. La función renal disminuyó progresivamente después de la cirugía. En comparación con el grupo control, en los otros dos grupos (Ob y Ob/KF) el nivel de leptina aumentó y el de adiponectina disminuyó (p < 0.01). Se observaron aumentos postquirúrgicos en la presión arterial, los lípidos, la creatinina y la insulina (p < 0.01). Conclusión: Este modelo se propone para el estudio de los mecanismos fisiopatológicos que conducen a la obesidad y las complicaciones de la función renal o cardiovascular.

Susceptibility to varicella-zoster infection in individuals 1 to 29 years of age in Mexico

Background. The prevalence of varicella zoster virus (VZV) infection has been poorly studied in Latin America. The aim of this work was to study the seroprevalence of antibody to VZV infection in Mexico. Infection was determined in 3,737 individuals. Methods. Samples were collected during a national serologic survey performed during 1987-1988 and represented individuals 1- to 29-years-old from all socioeconomic levels and from rural and urban communities throughout the country. Antibodies anti-VZV were measured with a commercially available enzyme-linked immunosorbent assay (VARELISA Merck, Germany). Results. In the population studied, 464 individuals (12.4 percent) were seronegative or susceptible to infection, whereas about 17.0 percent of individuals 1- to 19-years-old were susceptible to infection. Between the ages of 20 to 24 years, 8.4 percent were susceptible and between 25 to 29 years, 5.0 percent of persons were still susceptible to infection. Conclusions. Socioeconomic level, density of population, crowding, and gender were not found as risk factors for susceptibility to VZV infection in adolescents and young adults. Low educational level was found as a risk factor for susceptibility. High proportions of adolescents and young adults in Mexico are susceptible to VZV infection and should receive special attention when desingning vaccination programs