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ABSTRACT: BACKGROUND: We assessed anthropometric status, breastfeeding duration, morbidity, and mortality outcomes during the first four years of life according to gestational age, in three populationbased birth cohorts in the city of Pelotas, Southern Brazil. METHODS: Total breastfeeding duration, neonatal mortality, infant morbidity and mortality, and anthropometric measures taken at 12 and 48 months were evaluated in children of different gestational ages born in 1982, 1993 and 2004 in Southern Brazil. RESULTS: Babies born <34 weeks of gestation and those born between 34-36 weeks presented increased morbidity and mortality, were breastfed for shorter periods, and were more likely to be undernourished at 12 months of life, in comparison with the 39-41 weeks group. Children born with 37 weeks were more than twice as likely to die in the first year of life, and were also at increased risk of hospitalization and underweight at 12 months of life. Post-term infants presented an increased risk of neonatal mortality. CONCLUSION: The increased risks of morbidity and mortality among preterm (<37 weeks of gestation) and post-term (>41 weeks) are well known. In our population babies born at 37 also present increased risk. As the proportion of preterm and early term babies has increased markedly in recent years, this is a cause for great concern.
BMC Pediatrics 10/2012; 12(1):169. · 1.88 Impact Factor
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ABSTRACT: The Developmental Origins of Health and Disease hypothesis suggests that intrauterine, infancy and early childhood variables play a key role at programming later health. However, little is known on the programming of behavioral variables, because most studies so far focused on chronic disease-related and human capital outcomes. The aim of the present study was to evaluate the effects of prenatal, infancy and childhood weight and length/height gains on objectively-measured physical activity (PA) in adolescence.
This is a prospective birth cohort study in Pelotas, Brazil, including 457 adolescents (mean age: 13.3 years) with weight and length/height data at birth, one, three and six months, one and four years of age. PA was measured using a GT1M Actigraph accelerometer, and expressed as (a) minutes per day spent on sedentary, light, moderate, vigorous and very-vigorous activities; (b) total counts per day.
61.3% of the adolescents accumulated 60+ minutes of moderate-to-vigorous PA per day. Weight and length/height trajectories in infancy and childhood were similar between those classified as active or inactive at 13.3 years. However, those classified as inactive were heavier and taller at all ages; differences were statistically significant only in terms of length at three, six and 12 months.
Weight gain in infancy and childhood did not predict variability in adolescent PA, but those active in adolescence showed somewhat smaller average gains in length in infancy. These findings suggest that PA may partially be sensitive to early hormonal programming, or that genetic factors may affect both early growth and later metabolism or predisposition for PA.
International Journal of Behavioral Nutrition and Physical Activity 07/2012; 9:82. · 3.83 Impact Factor
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ABSTRACT: OBJECTIVE: To investigate the predictors of change in physical activity (PA) from early to mid adolescence in a cohort of adolescents. DESIGN: Prospective, population-based birth cohort study. PA level was evaluated by means of questionnaire, and was analysed in continuous form (min/week) and as a trajectory (inactive-inactive, inactive-active, active-inactive, active-active) based on the cut-off point of 300 min/week. SETTING: Pelotas, a city of 340 000 inhabitants in southern Brazil. SUBJECTS: Adolescents (n 4120) followed from 11 to 15 years of age. RESULTS: Maternal PA change and more exposure to outdoors were directly associated with a positive change in PA level (min/week) for both genders. Higher maturation status (among boys) and later menarche were also associated with positive PA change in min/week. Predictors to remain inactive were: maternal PA change (inverse association), more exposure to outdoors, higher socio-economic level, fear of living in the neighbourhood and non-overweight girls. Predictors to become inactive were higher socio-economic level among boys and increase in screen time among girls. CONCLUSIONS: The study demonstrates that social, family, biological, behavioural and environmental factors exert an important role in the PA change among youngsters as they move into adolescence. These findings may be relevant to the design of policies and intervention programmes aimed at promoting PA in teenagers.
Public Health Nutrition 03/2012; · 2.17 Impact Factor
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ABSTRACT: To investigate the clustering of risk behaviors for chronic non-communicable diseases and their associated factors among adolescents from Southern Brazil.
In 2008, a survey was conducted with 3990 adolescents aged 14-15 years (mean: 14.3; SD: 0.6) from the 1993 Pelotas Birth Cohort Study. Clustering was determined by comparing observed (O) and expected (E) prevalence of all possible combinations of the four risk factors investigated (smoking, alcohol intake, low fruit intake, and physical inactivity). We carried out Poisson regression to evaluate the effect of individual characteristics on the presence of at least three risk behaviors.
All risk factors tended to cluster together (O/E prevalence=3.0), especially smoking and alcohol intake (odds ratio to present on behavior in the presence of other >5.0). Approximately 15% of adolescents displayed three or more risk behaviors. Females (adjusted OR=1.55), people 15 years and older (OR=1.47), with black skin color (OR=1.23), and of low socioeconomic level (OR=1.29) were more likely to display three or more risk factors.
These findings suggest that lifestyle-related risk factors tend to cluster among adolescents. Identifying subgroups at greater risk of simultaneously engaging in multiple risk behaviors may aid in the planning of preventive strategies.
Preventive Medicine 03/2012; 54(6):393-6. · 3.22 Impact Factor
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ABSTRACT: To evaluate the prevalence of and factors associated with discrimination self-reported by adolescents.
Cross-sectional analysis of adolescents belonging to a cohort of live births in 1993 in the city of Pelotas, Brazil. From the 5 249 members of the cohort, information was collected from 4 452 adolescents in 2004 and 2005 regarding self-reported discrimination, sociodemographic variables, physical attributes, and nutritional status. A Poisson regression was utilized in the raw and adjusted analyses to estimate prevalence rates (RP).
The global prevalence of self-reported discrimination was 16.4%. In the adjusted analysis, discrimination was reported more by the following groups: girls (RP = 1.27, 95%CI: 1.10-1.48), people identified by others as black (RP = 1.28, 95%CI: 1.04-1.57), poorer adolescents (RP = 1.58, 95%CI: 1.23-2.02), those who perceived themselves to be very thin or very fat (RP = 1.81 and 1.54 respectively), those whose families had financial trouble (RP = 1.76, 95%CI: 1.49-2.08), those who wore glasses (RP = 1.74, 95%CI: 1.45-2.10), those who thought their teeth looked bad (RP = 1.58, 95%CI: 1.21-2.07), those who had been reprimanded in school (RP = 1.23, 95%CI: 1.01- 1.51), and those who had been involved in fights in the past year (RP = 1.62, 95%CI: 1.36-1.94). The association between discrimination and nutritional status varied by sex (interaction P = 0.009). Thin children reported greater discrimination than those who were overweight or obese. Discrimination on the basis of obesity was higher among girls, with this effect more strongly felt among rich girls than among poor ones.
Self-reported discrimination was prevalent and unequally distributed among the population. Actions to reduce experiences of discrimination must be implemented during the initial stages of life.
Revista Panamericana de Salud Pública 03/2012; 31(3):204-10. · 0.85 Impact Factor
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ABSTRACT: To analyze factors associated with the practice of physical activity during pregnancy and its relationship to maternal and child health indicators.
Cross-sectional study carried out with all births that occurred at maternity hospitals in the municipality of Rio Grande (Southern Brazil) during the year of 2007 (N = 2,557). Information was collected through interviews, by means of a pre-coded questionnaire administered to the mothers. The analyzed maternal and child health outcomes were: hospitalization during pregnancy, cesarean delivery, preterm birth (gestational age < 37 weeks), low birth weight (< 2500g), and fetal death.
A total of 32.8% of mothers (95%CI 31.0;34.6) reported having practiced physical activity during pregnancy. The factors associated with practice of physical activity during pregnancy, after adjusting for potential confounders, were: maternal age (inverse association), level of schooling (direct association), mother's first pregnancy, having received prenatal care, and having been instructed in physical activity during prenatal care. Women who practiced physical activity during pregnancy were less likely to deliver surgically and to have a stillbirth. There was no association between physical activity and preterm birth, hospitalization, and low birth weight.
Only one third of mothers reported having practiced physical activity during pregnancy. This behavior was more frequent among younger women with higher level of schooling who were advised during prenatal care. Women who practiced physical activity during pregnancy had fewer cesarean sections and lower occurrence of stillbirths.
Revista de saude publica 02/2012; 46(2):327-33. · 1.01 Impact Factor
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ABSTRACT: This study aimed to: 1) describe the change in leisure-time physical activity (LTPA) during early-to-mid adolescence; 2) analyze the tracking of LTPA; 3) identify the predictors of LTPA change. 4,120 adolescents were from 11 to 15 years old. Outcome was self-reported LTPA (min/wk). Boys increased their LTPA level over the four years (mean: 75 min/wk; 95%CI: 49,100), whereas a decrease was observed among girls (mean: -42 min/wk; 95%CI: -57,-28). Likelihood to be active at 15 years of age was 50% higher (95%CI: 39-62) among those who were active at 11 years. The main predictor of LTPA change was the number of physical activities performed at baseline. Regular physical activity early in life can predict this behavior afterward.
Pediatric exercise science 02/2012; 24(1):58-71. · 1.71 Impact Factor
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ABSTRACT: There are discrepancies in the literature regarding time trends in the occurrence of asthma in adults. This study compared asthma prevalence in two cross-sectional studies with a ten-year interval in Pelotas, Rio Grande do Sul State, Brazil. The first, in 2000, included 1,968 individuals, and the second, in 2010, 2,466 adults (20-69 years). Prevalence of wheezing and shortness of breath in the prior 12 months remained the same after ten years (6% and 6.1%, respectively). In both studies, asthma was more frequent among females and people with low family income. Physician-diagnosed asthma increased by 35.6%, and lifetime incidence of asthma, by 32.2%. There was no percentage change in current asthma symptoms or current asthma. Local socioeconomic improvement between the two studies was consistent with the increase in medical diagnosis, but did not reflect better management of asthma symptoms, underlining the need for investment regarding other determinants of the disease.
Cadernos de saúde pública / Ministério da Saúde, Fundação Oswaldo Cruz, Escola Nacional de Saúde Pública 01/2012; 28(1):135-44. · 0.83 Impact Factor
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ABSTRACT: The aim of this study was to investigate the cross-sectional and prospective associations between physical activity and body composition in adolescence. This is a prospective study, including 4,103 adolescents belonging to the Pelotas (Brazil) 1993 birth cohort, who were followed up at the mean ages of 11.3 and 14.7 years. Subsample analyses included 511 individuals with accelerometry and deuterium dilution data at 13.3 years. Sum of skinfolds at age 11.3 years was highly correlated with skinfolds at age 14.7 years (rho = 0.74, P < 0.001). More than 85% of participants remained in the same quintile or changed by not more than one quintile during the 3.4 year period. Tracking of physical activity was considerably lower, although still significant; the correlation was 0.24 (P < 0.001) and 61.4% of the adolescents moved one or less quintiles. In fully-adjusted models, no significant cross-sectional or longitudinal associations were found between physical activity and body composition, neither in boys nor in girls. These null results were confirmed in the 511 individuals with accelerometry and deuterium data. We provide evidence of tracking of physical activity and particularly body composition during adolescence. Our results do not support the hypothesis that physical activity and fatness are strongly related in adolescents.
Journal of Sports Sciences 12/2011; 30(2):183-90. · 1.93 Impact Factor
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ABSTRACT: Birth weight has been inversely associated with later blood pressure. Firstborns tend to have lower birth weight than their later-born peers, but the long-term consequences remain unclear. The study objective was to investigate differences between firstborn and later-born individuals in early growth patterns, body composition, and blood pressure in Brazilian adolescents. The authors studied 453 adolescents aged 13.3 years from the prospective 1993 Pelotas Birth Cohort. Anthropometry, blood pressure, physical activity by accelerometry, and body composition by deuterium were measured. Firstborns (n = 143) had significantly lower birth weight than later borns (n = 310). At 4 years, firstborns had significantly greater weight and height, indicating a substantial overshoot in catch-up growth. In adolescence, first borns had significantly greater height and blood pressure and a lower activity level. The difference in systolic blood pressure could be attributed to variability in early growth and that in diastolic blood pressure to reduced physical activity. The magnitude of increased blood pressure is clinically significant; hence, birth order is an important developmental predictor of cardiovascular risk in this population. Firstborns may be more sensitive to environmental factors that promote catch-up growth, and this information could potentially be used in nutritional management to prevent catch-up "overshoot."
American journal of epidemiology 09/2011; 174(9):1028-35. · 5.59 Impact Factor
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ABSTRACT: The aim of this study was to evaluate the association between size at birth and mental health problems at 11 years of age in the 1993 Pelotas (Brazil) Birth Cohort Study. Newborns were weighed and measured, and anthropometric indices were calculated. At 11 years of age, mental health problems were assessed using the Strengths and Difficulties Questionnaire (SDQ). Prevalence of mental health problems was 32% (95%CI: 31-33). After adjusting for potential confounders, newborns with weight and body mass index (BMI) for age z-scores < -2 SD were at 27% (95%CI: 7-49) and 29% (95%CI: 10-51) greater risk, respectively, of developing mental health problems at age 11 years than those born with normal scores. Newborns with BMI and head circumference for age z-scores > +2 SD were at 34% (95%CI: 6-71) and 19% (95%CI: 1-40) greater risk, respectively, of developing mental health problems than those with normal scores. The results suggest that early factors that are reflected as size measurements at birth can cause mental health problems later in life.
Cadernos de saúde pública / Ministério da Saúde, Fundação Oswaldo Cruz, Escola Nacional de Saúde Pública 08/2011; 27(8):1622-32. · 0.83 Impact Factor
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Ana M B Menezes, Samuel C Dumith,
Jeovany Martínez-Mesa,
Alexandre Emidio Ribeiro Silva,
Andreia Morales Cascaes,
Giovanna Gatica Domínguez,
Fabiana Vargas Ferreira,
Giovanny Araújo França,
Josiane Dias Damé,
Kátia Márcia António Ngale,
Cora L Araújo,
Luciana Anselmi
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ABSTRACT: To analyze the association between mental health problems and smoking in adolescents.
A total of 4,325 adolescents aged 15 from the 1993 birth cohort of the city of Pelotas, Southern Brazil, was studied. Smoking was defined as having smoked one or more cigarettes in the previous 30 days. Mental health was assessed according to the total score of the Strengths and Difficulties Questionnaire. Score > 20 points was considered positive. Data were analyzed using Poisson regression with adjustment for robust variance.
Smoking prevalence was 6.0% and about 30% of the adolescents presented some mental health problem. In the crude analysis, the prevalence ratio for smoking was 3.3 (95%CI 2.5; 4.2). After the adjusted analysis (for sex, age, skin color, family income, mother's level of schooling, group of friends who smoke, employment in the previous year, school failure, physical activity during leisure time and experimental use of alcohol), it decreased to 1.7 (95%CI 1.2; 2.3) among those with mental health problem.
Mental health problems in adolescence may be related to tobacco consumption.
Revista de saude publica 05/2011; 45(4):700-5. · 1.01 Impact Factor
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ABSTRACT: To describe the worldwide prevalence of physical inactivity and to analyze its association with development level of each country.
Pooled analysis of three multicenter studies, conducted between 2002 and 2004, which investigated the prevalence of physical inactivity in 76 countries, and comprised almost 300,000 individuals aged 15 years or older. Each study used the International Physical Activity Questionnaire to assess physical inactivity. The level of development of each country was analyzed by the Human Development Index (HDI).
The crude worldwide prevalence of physical inactivity was 21.4% (95%CI 18.4-24.3), being higher among women (mean=23.7%, 95%CI 20.4-27.1) than men (mean=18.9%, 95%CI 16.2-21.7). It ranged from 2.6% (in Comoros) to 62.3% (in Mauritania), with a median equal to 18%. After weighting for the total population of each country, the worldwide prevalence of physical inactivity was 17.4% (95%CI 15.1-19.7). There was a positive association between HDI and prevalence of physical inactivity (rho=0.27). Less developed countries showed the lowest prevalence of physical inactivity (18.7%), while physical inactivity was more prevalent among the most developed countries (27.8%).
One out of five adults around the world is physically inactive. Physical inactivity was more prevalent among wealthier and urban countries, and among women and elderly individuals.
Preventive Medicine 02/2011; 53(1-2):24-8. · 3.22 Impact Factor
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ABSTRACT: Although there is longstanding evidence of the short-term benefits of promoting rapid growth for young children in low-income settings, more recent studies suggest that early weight gain can also increase the risk of chronic diseases in adults. This paper attempts to separate the effects of early life weight and length/height gains on blood pressure, body mass index (BMI), sum of skin folds and subscapular/triceps skin fold ratio at 14-15 years of age.
The sample comprised 833 members of a prospective population-based birth cohort from Brazil. Conditional size (weight or height) analyses were used to express the difference between observed size at a given age and expected size based on a regression, including all previous measures of the same anthropometric index. A positive conditional weight or height indicates growing faster than expected given prior size.
Conditional weights at all age ranges were positively associated with most outcomes; each z-score of conditional weight at 4 years was associated with an increase of 6.1 mm in the sum of skin folds (95% CI 4.5 to 7.6) in adolescence after adjustment for conditional length/height. Associations of the outcomes with conditional length/height were mostly negative or non-significant-each z-score was associated with a reduction of 2.4 mm (95% CI -3.8 to -1.1) in the sum of skin folds after adjustment for conditional weight. No associations were found with the skin fold ratio.
The promotion of rapid length/height gain without excessive weight gain seems to be beneficial for long-term outcomes, but this requires confirmation from other studies.
Journal of epidemiology and community health 02/2011; 66(2):149-54. · 3.04 Impact Factor
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ABSTRACT: Socioeconomic status (SES) has been shown to be an important contributor to lung function. The aim of this study was to evaluate the association between lung function in adolescence and (a) SES at birth; (b) SES in adolescence; (c) SES trajectory from birth to adolescence ('never poor', 'non poor-poor', 'poor-non poor' and 'always poor'). Additionally, we investigate the role of adolescent and parental variables at mediating these associations.
Prospective birth cohort study in Pelotas, Brazil, including 4,005 adolescents (mean age: 14.7 years) followed up from birth. Lung function was measured by spirometry. Outcome variables were forced expiratory volume in one second in liters (FEV1) and forced vital capacity also in liters (FVC).
Mean FEV1 was 3.46 L (95%CI 3.43-3.49) among boys and 2.93 L (95%CI 2.91-2.95) among girls. Mean FVC was 4.00 L (95%CI 3.97; 4.04) among boys and 3.30 L (95%CI 3.27; 3.32) among girls. SES at birth, in adolescence and its trajectory from birth to adolescence were inversely associated with lung function in both adolescent boys and girls. After adjustment for mediating variables, coefficients were largely reduced, particularly among boys, and the main predictor of change in coefficients was the inclusion of height in the models.
Low income adolescents from Brazil present impaired lung function as compared to the better off, and this is largely explained by height.
BMC Public Health 01/2011; 11:596. · 2.00 Impact Factor
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ABSTRACT: It is presumed that physical activity (PA) level declines during the lifespan, particularly in adolescence. However, currently, there is no study that quantifies these changes and pools results for a common interpretation. Therefore, the purpose was to systematically review the international literature regarding PA change during adolescence, and to quantify that change according to a series of study variables, exploring gender-and-age differences.
An electronic search was conducted in the Medline/PubMed and Web of Science databases. Longitudinal studies with, at least, two PA measures throughout adolescence (10-19 years old) or the first PA measure during childhood and the second one during adolescence were selected. From each article, study project name, country, year of the first data collection, sample size, baseline age, follow-up duration, characteristics of the instrument (type, recall time, PA intensity and PA domain), unit of PA measure and report of statistical significance were collected.
Overall, 26 studies matched the inclusion criteria. Most were carried out in the USA, assessed PA by questionnaire, and found a decline in PA levels during the adolescence. On average, the mean percentage PA change per year, across all studies, was -7.0 (95% confidence interval: -8.8 to -5.2), ranging from -18.8 to 7.8. The decline was significant according to most sub-groups of variables analysed. Although earlier studies revealed a higher PA decline in boys, the decline has been greater in girls in more recent studies (commenced after 1997). Moreover, although the decline among girls was higher in younger ages at baseline (9-12 years), it was higher in older ages (13-16 years) among boys.
The decline of PA during adolescence is a consistent finding in the literature. Differences between boys and girls were observed and should be explored in future studies. Interventions that attempt to attenuate the PA decline, even without an increase in PA levels, could be considered as effective.
International Journal of Epidemiology 01/2011; 40(3):685-98. · 6.41 Impact Factor
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ABSTRACT: The aim of this study is to describe the methodology of the 2004-2005 follow-up visit of the 1993 Pelotas (Brazil) birth cohort. All children born in Pelotas in 1993 and whose mothers lived in the city at that time were eligible to be enrolled in a longitudinal study. Between July 2004 and March 2005, all cohort participants were sought for a follow-up visit. Several strategies were used to help trace cohort members, including a census of the city's schools and a census of all households in the municipality. The Mortality Information System was monitored in order to identify deaths among cohort members. Of the 5,249 cohort members, 4,452 were interviewed in 2004-5. When added to the 141 deaths, these represent 87.5% of the original cohort. In spite of the logistic and financial difficulties, it is possible to carry out prospective studies with long-term follow-up in the Brazilian context.
Cadernos de saúde pública / Ministério da Saúde, Fundação Oswaldo Cruz, Escola Nacional de Saúde Pública 10/2010; 26(10):1875-86. · 0.83 Impact Factor
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ABSTRACT: Studies on well-being and its possible determinants are rare in the international literature, and almost non-existent in Brazil, particularly among youth. The present study focused on the epidemiology of well-being among adolescents belonging to a birth cohort. Well-being was measured using face-to-face interviews, with a question whose answer was based on a graphic scale of faces. 4,452 adolescents were interviewed. Approximately half (49.4%) classified themselves as very happy (face 1); this proportion was higher among girls than boys. Poorer adolescents were more likely than their wealthier peers to identify with the happiest face (number 1), but were also more likely to report moderate to low levels of well-being (faces 3-7). Body mass index was inversely associated with well-being. Among girls, physical activity was directly associated with well-being.
Cadernos de saúde pública / Ministério da Saúde, Fundação Oswaldo Cruz, Escola Nacional de Saúde Pública 10/2010; 26(10):1887-94. · 0.83 Impact Factor
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ABSTRACT: The aim of this study was to estimate the prevalence of sedentary behavior and investigate associated factors in adolescents 11 years of age from the 1993 birth cohort in Pelotas, Rio Grande do Sul State, Brazil. Sedentary behavior was investigated with a questionnaire, and was defined as spending more than two hours per day watching television, playing videogames, or using the computer. Of the 4,452 adolescents interviewed, 98% reported watching television, 44% playing videogames, and 22% using the computer. The average time spent on each of these electronic media was 197, 36, and 17 minutes per day, respectively. Prevalence of sedentary behavior was 79.7% (95%CI: 78.6; 80.9) and showed a positive association with socioeconomic level and nutritional status and a negative association with well-being. These 11-year-olds spent extensive time at TV viewing, videogames, and the computer. Special attention should be given to the most exposed groups of adolescents, including the more affluent, overweight, and those with limited schooling.
Cadernos de saúde pública / Ministério da Saúde, Fundação Oswaldo Cruz, Escola Nacional de Saúde Pública 10/2010; 26(10):1928-36. · 0.83 Impact Factor
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ABSTRACT: The aim of this prospective analysis was to describe the cumulative incidence of hospital admissions in the first year of life and between 1 and 11 years of age and to explore associated factors. Hospital admissions were collected through regular monitoring in the first year of life, and through maternal report on admissions between 1 and 11 years. Analyses were stratified by sex and adjusted for confounding factors. 18.1% of children were hospitalized in the first year of life, and 30.7% between ages 1 and 11 years. Among boys, hospital admission in the first year was associated with low family income, paternal smoking during pregnancy, preterm delivery, and low birthweight. Among girls, in addition to the variables described for boys, black/mixed skin color was also a risk factor for hospital admission. For admissions between 1 and 11 years of age, low family income and gestational age > 37 weeks were found to be significant risk factors.
Cadernos de saúde pública / Ministério da Saúde, Fundação Oswaldo Cruz, Escola Nacional de Saúde Pública 10/2010; 26(10):1980-9. · 0.83 Impact Factor
