Cesarean section and increased body mass index in school children: two cohort studies from distinct socioeconomic background areas in Brazil

Abstract Background Recent studies have raised controversy regarding the association between cesarean section and later obesity in the offspring. The purpose of this study was to assess the association of cesarean section with increased body mass index (BMI) and obesity in school children from two Brazilian cities with distinct socioeconomic backgrounds. Methods Two birth cohorts respectively born in 1994 in Ribeirao Preto, a wealthy city in Southeast, and in 1997/98 in Sao Luis, a less wealthy city in Northeast of Brasil, were evaluated. After birth, 2,846 pairs of mothers-newborns were evaluated in Ribeirao Preto and 2,542 in Sao Luis. In 2004/05, 790 children aged 10/11 years were randomly reassessed in Ribeirao Preto and 673 at 7/9 years in Sao Luis. Information on type of delivery, maternal and child characteristics, socioeconomic position and anthropometric measurements were collected after birth and at school age. Obesity was defined as BMI ≥ 95th percentile at school age. Results Obesity rate was 13.0% in Ribeirao Preto and 2.1% in Sao Luis. Cesarean section was associated with obesity and remained significant after adjustment only in Ribeirao Preto [OR = 1.74 (95% CI: 1.04; 2.92)]. The association between cesarean section and BMI remained significant after adjustment for maternal schooling, maternal smoking during pregnancy, duration of breastfeeding, gender, birth weight and gestational age, type of school and, only in Sao Luis, pre-pregnancy maternal weight. In Ribeirao Preto children born by cesarean section had BMI 0.31 kg/m2 (95%CI: 0.11; 0.51) higher than those born by vaginal delivery. In Sao Luis BMI of children born by cesarean section was 0.28 kg/m2 higher (95%CI: 0.08; 0.49) than those born by vaginal delivery. Conclusion A positive association between cesarean section and increased BMI z-score was demonstrated in areas with different socioeconomic status in a middle-income country.

Progress in animal experimentation ethics. A case study from a brazilian medical school and from the international medical literature

PURPOSE: This study describes in Brazil and in the global biomedical community the time course of the development of animal research welfare guidelines. METHODS: The database of the Ethics Committee of the Faculty of Medicine of Ribeirao Preto (EC/FMRP-USP), Brazil, was surveyed since its inception in 2002 as the regulations became more stringent to provide better protection of animal research welfare at this institution. Medline database was evaluated to identify the number of publications in the period between 1968 and 2008 that used research animals and were in compliance with established ethics guidelines. RESULTS: The EC/FMRP-USP evaluated 979 projects up until 2009. Most of the applications came from Department of Physiology and the most frequently requested species was the rat. In 2004, national research funding agencies started to request prior approval from institutional review ethics committees prior to application review and this requirement became federal law in Brazil in 2008. The analysis of international publications revealed a relative reduction in studies involving research animals (18% in 1968 to 7.5% in 2008). CONCLUSIONS: The present work showed that in the last four decades major changes occurred in the guidelines dictating use of research animals occurred and they are being adopted by developing countries. Moreover, animal welfare concern in the scientific community preceded the introduction of journal guidelines for this purpose. Furthermore, in Brazil it was anticipated that laws were needed to protect animal research welfare from being not upheld.

Methods of body-mass reduction by combat sport athletes

The aim of this study was to investigate the methods adopted to reduce body mass (BM) in competitive athletes from the grappling (judo, jujitsu) and striking (karate and tae kwon do) combat sports in the state of Minas Gerais, Brazil. An exploratory methodology was employed through descriptive research, using a standardized questionnaire with objective questions self-administered to 580 athletes (25.0 +/- 3.7 yr, 74.5 +/- 9.7 kg, and 16.4% +/- 5.1% body fat). Regardless of the sport, 60% of the athletes reported using a method of rapid weight loss (RWL) through increased energy expenditure. Strikers tend to begin reducing BM during adolescence. Furthermore, 50% of the sample used saunas and plastic clothing, and only 26.1% received advice from a nutritionist. The authors conclude that a high percentage of athletes uses RWL methods. In addition, a high percentage of athletes uses unapproved or prohibited methods such as diuretics, saunas, and plastic clothing. The age at which combat sport athletes reduce BM for the first time is also worrying, especially among strikers.

Nutritional transition of school children from low income families of a northeastern urban area, Brazil

Background: Evaluating child growth is, in practice, performed by measuring the development of a child's weight, height, and body composition in comparison to averages observed among a reference population. Objective: To describe the nutritional status of children of low income families who live in urban region in northeastern Brazil. Methods: This study is a population case series with a transversal and observational design. The study population consisted of 257 children, aged 5 to 10 years, who were enrolled in a public school to children of low income families. We used the cutoff point for short stature of -2 Z scores for age, and underweight, overweight, and obese were classified as the 5th, 85th, and 95th percentiles, respectively, of the body mass index (BMI) for age, with both classifications in accordance with the Center for Disease Control and Prevention (CDC 2000). Comparisons by gender were performed for the measures of the central tendency and the frequency of diagnoses, in addition to the tendency of the evolution of BMI by age. Results: The prevalence of short stature was 3.5% (95% CI: 1.9-6.5). In the evaluation of BMI for age, the prevalences found for underweight, overweight, and obese were 5.8% (95% CI: 3.6-9.4), 4.7% (95% CI: 2.7-8.0), and 2.3% (95% CI: 1.1-5.0), respectively. We found a significant trend in the reduction of BMI with the increase in age. Conclusions: According to CDC references, the prevalences of underweight and short stature were higher than expected and for the overweight and obesity were lower than expected, indicating that the nutritional transition had still not reached, as commonly is described, these low income children from the urban outskirts of the Northeast region.

Urban air pollution: a representative survey of PM2.5 mass concentrations in six Brazilian cities

In urban areas of Brazil, vehicle emissions are the principal source of fine particulate matter (PM2.5). The World Health Organization air quality guidelines state that the annual mean concentration of PM2.5 should be below 10 mu g m(-3). In a collaboration of Brazilian institutions, coordinated by the University of Sao Paulo School of Medicine and conducted from June 2007 to August 2008, PM2.5 mass was monitored at sites with high traffic volumes in six Brazilian state capitals. We employed gravimetry to determine PM2.5 mass concentrations, reflectance to quantify black carbon concentrations, X-ray fluorescence to characterize elemental composition, and ion chromatography to determine the composition and concentrations of anions and cations. Mean PM2.5 concentrations and proportions of black carbon (BC) in the cities of Sao Paulo, Rio de Janeiro, Belo Horizonte, Curitiba, Recife, and Porto Alegre were 28.1 +/- 13.6 mu g m(-3) (38% BC), 17.2 +/- 11.2 mu g m(-3) (20% BC), 14.7 +/- 7.7 mu g m(-3) (31% BC), 14.4 +/- 9.5 mu g m(-3) (30% BC), 7.3 +/- 3.1 mu g m(-3) (26% BC), and 13.4 +/- 9.9 mu g m(-3) (26% BC), respectively. Sulfur and minerals (Al, Si, Ca, and Fe), derived from fuel combustion and soil resuspension, respectively, were the principal elements of the PM2.5 mass. We discuss the long-term health effects for each metropolitan region in terms of excess mortality risk, which translates to greater health care expenditures. This information could prove useful to decision makers at local environmental agencies.

Progress in animal experimentation ethics: a case study from a Brazilian medical school and from the international medical literature

PURPOSE: This study describes in Brazil and in the global biomedical community the time course of the development of animal research welfare guidelines. METHODS: The database of the Ethics Committee of the Faculty of Medicine of Ribeirao Preto (EC/FMRP-USP), Brazil, was surveyed since its inception in 2002 as the regulations became more stringent to provide better protection of animal research welfare at this institution. Medline database was evaluated to identify the number of publications in the period between 1968 and 2008 that used research animals and were in compliance with established ethics guidelines. RESULTS: The EC/FMRP-USP evaluated 979 projects up until 2009. Most of the applications came from Department of Physiology and the most frequently requested species was the rat. In 2004, national research funding agencies started to request prior approval from institutional review ethics committees prior to application review and this requirement became federal law in Brazil in 2008. The analysis of international publications revealed a relative reduction in studies involving research animals (18% in 1968 to 7.5% in 2008). CONCLUSIONS: The present work showed that in the last four decades major changes occurred in the guidelines dictating use of research animals occurred and they are being adopted by developing countries. Moreover, animal welfare concern in the scientific community preceded the introduction of journal guidelines for this purpose. Furthermore, in Brazil it was anticipated that laws were needed to protect animal research welfare from being not upheld.