[Show abstract][Hide abstract] ABSTRACT: There are no prospective studies investigating the effects of sugar-related feeding practices on changes in dental caries from early childhood to young adulthood. The aim of this study was to assess whether sugar-related feeding practices affect dental caries between the ages of 6 and 18 y. This birth cohort study was initiated in 1993 in Pelotas, Brazil. There were 3 dental clinical assessments; at ages 6 y (n = 359), 12 y (n = 339), and 18 y (n = 307). Sugar-related feeding practices were assessed at ages 4, 15, and 18 y. Covariates included sex and life course variables, such as family income, breast-feeding, mother's education, regularity of dental visit, and child's toothbrushing habits. Group-based trajectory analysis was performed to characterize trajectories of time-varying independent variables that had at least 3 time points. We fitted a generalized linear mixed model assuming negative binomial distribution with log link function on 3-time repeated dental caries assessments. One in 5 participants was classified as "high" sugar consumers, and nearly 40% were "upward consumers." "Low consumers" accounted for >40% of the sample. High and upward sugar consumers had higher dental caries prevalence and mean DMFT in all cohort waves when compared with low sugar consumers. Caries occurred at a relatively constant rate over the period of study, but in all sugar consumption groups, the increment of dental caries was slightly higher between ages 6 and 12 y than between 12 and 18 y. Adjusted analysis showed that dental caries increment ratio between ages 6 and 18 y was 20% and 66% higher in upward and high sugar consumer groups as compared with low consumers. The higher the sugar consumption along the life course, the higher the dental caries increment. Even the low level of sugar consumption was related to dental caries, despite the use of fluoride.
Full-text · Article · Jan 2016 · Journal of dental research
[Show abstract][Hide abstract] ABSTRACT: Conflicting results exist about the short-and long-term effects of breastfeeding on bone mineral content (BMC) and bone mineral density (BMD). We conducted a systematic review to assess the relationship between method of infant feeding and bone mass in children, adolescents and adults.
The literature review was concluded in September 2014 in MEDLINE, Web of Science and LILACS databases and articles published between 1998 and 2013 were included. Studies using dual-energy X-ray absorptiometry (DXA) instrument to assess the bone mineral content and/or bone mineral density (BMD) of total body, lumbar spine, femoral neck, or at least one of these sites were included in the review.
From the 648 references identified, eleven were selected, ten of which had a longitudinal design. All studies were conducted in high-income countries, six evaluated the outcome in children, four in adolescents and one in young adults (<35 years). Of the studies that assessed the outcome in childhood, two found a positive association and the others showed a negative effect of being breastfed on bone mass. In adolescence, three studies showed a positive association between being breastfed and bone outcomes. Among adults, a negative effect of being breastfed exclusively for a longer period of time on bone mass was observed only in men. In women, there was no effect of being breastfed on bone mass.
There is no consensus on the effects of method of infant feeding on an individual’s bone mass at different ages.
Preview · Article · Dec 2015 · International Breastfeeding Journal
[Show abstract][Hide abstract] ABSTRACT: O objetivo deste artigo é descrever a qualidade da dieta de adolescentes segundo fatores sociodemográficos e comportamentais. Estudo transversal com 3.959 adolescentes de dezoito anos de idade, pertencentes à coorte de nascimentos de 1993, de Pelotas, Rio Grande do Sul, Brasil. O consumo alimentar foi avaliado através de um Questionário de Frequência Alimentar semiquantitativo, com período recordatório de 12 meses. A qualidade da dieta foi avaliada através do Índice de Qualidade da Dieta Revisado (IQD-R). Este índice varia de 0 a 100 pontos e quanto maior a pontuação, melhor a qualidade da dieta. A média geral do escore do IQD-R foi de 62,4 pontos (DP 12). Adolescentes com cor da pele não branca (63,1), provenientes de familias cujos chefes tinham menor escolaridade (63,6) e pertencentes ao menor quintil do índice de bens (64,7) apresentaram maiores médias no escore do IQD-R. Menores médias foram encontradas entre adolescentes que fumavam (58,5) e que consumiam bebida alcoólica (56,0). Este estudo mostrou que a qualidade da dieta dos adolescentes avaliados merece atenção, especialmente no que se refere à ingestão de vegetais, leites e derivados.
[Show abstract][Hide abstract] ABSTRACT: Background:
A rapid gain in weight for length may put children at a higher risk of noncommunicable diseases later in life.
The objective of this study was to assess the long-term effects of nutrition counseling delivered in the first 2 y of life in Pelotas, a city in Southern Brazil.
The original cluster-randomized controlled trial was conducted in 1998. Nutrition counseling (breastfeeding promotion and increased intake of micronutrient-rich and energy-dense foods) was delivered to mothers of children aged 0-17.9 mo attending primary care. Six months later, weight gain was higher in the intervention group than in the control group for children ≥12 mo of age at enrollment. In 2013 (mean age 15 y), assessments included anthropometric measurements; body composition (air-displacement plethysmography); body shape (3-dimensional photonic scan); and plasma total, LDL, and HDL cholesterol, triglycerides, C-reactive protein, and glucose.
A total of 363 of the 424 original participants were assessed. An a priori decision was made to prioritize analyses of subjects aged 12-17.9 mo at enrollment (51 from the intervention group and 45 from the control group). In this subgroup, boys in the intervention group were [mean (95% CI)] 3.4 (0.8, 6.0) cm taller than those in the control group. Systolic blood pressure tended to be 5.2 (-0.8, 11.1) mm Hg higher in male subjects from the intervention group than in those in the control group. Lipid profiles tended to be healthier in the intervention group. The plasma total cholesterol concentration was -17.8 (-29.8, -5.7) mg/dL lower in boys in the intervention group than in those in the control group. The total-to-HDL cholesterol ratio and triglyceride concentration in the girls in the intervention group were -0.4 (-0.6, -0.1) and -26.3 (-46.3, -6.3) mg/dL, respectively, lower than in the control group. There was no difference between the groups in terms of body composition.
Promotion of weight gain in children between 12.0-17.9 mo of age was not associated with higher metabolic risk 15 y later. On the contrary, there was some evidence of reduced metabolic risk in the intervention group.
No preview · Article · Oct 2015 · Journal of Nutrition
[Show abstract][Hide abstract] ABSTRACT: Objective:
This study aimed to develop and validate equations to estimate body fat based on anthropometric measurements of subcutaneous fat thickness (SFT) and muscle thickness (MT) measured by A-mode ultrasound (BodyMetrix) in Brazilian adults.
Individuals (n = 206) underwent air-displacement plethysmography for body composition assessment. Arm, thigh, and calf circumferences were also obtained. SFT from triceps, biceps, subscapular, abdominal, thigh, and calf regions and MT from triceps, biceps, thigh, and calf regions were measured by BodyMetrix. Prediction equations were developed by stepwise multiple linear regression using the circumferences, weight, height, SFT, and MT. Lin's concordance correlation coefficient, mean difference, and 95% limits of agreement (95% LOA) were assessed in apparent and internal validity.
The prediction equation for whole-body fat for men included thigh circumference, triceps and thigh SFT, biceps MT, weight, and height. The equation for women included age, calf circumference, abdominal and calf SFT, weight, and height. The prediction equation overestimated men's whole-body fat by 0.5 percentual points, in average, and the lower and upper 95% LOA were -6.8% and 7.7%, respectively. For women, the prediction equation overestimated whole-body fat by 0.1 percentual points, in average. Lower and upper 95% LOA were -6.5% and 6.7%, respectively. Optimism-adjusted results using 500 repetitions with same size samples have shown similar results. Body fat extremes did not influence the whole-body fat estimation.
BodyMetrix A-mode ultrasound, in association with selected conventional anthropometric measurements, proved to be a reliable tool for the estimation of body fat percentage.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to estimate the association between birth order and number of siblings with body composition in adolescents. Data are from a birth cohort study conducted in Pelotas, Brazil. At the age of 18 years, 4563 adolescents were located, of whom 4106 were interviewed (follow-up rate 81·3 %). Of these, 3974 had complete data and were thus included in our analysis. The variables used in the analysis were measured during the perinatal period, or at 11, 15 and/or 18 years of age. Body composition at 18 years was collected by air displacement plethysmography (BOD POD®). Crude and adjusted analyses of the association between birth order and number of siblings with body composition were performed using linear regression. All analyses were stratified by the adolescent sex. The means of BMI, fat mass index and fat-free mass index among adolescents were 23·4 (sd 4·5) kg/m2, 6·1 (sd 3·9) kg/m2 and 17·3 (sd 2·5) kg/m2, respectively. In adjusted models, the total siblings remained inversely associated with fat mass index (β = - 0·37 z-scores, 95 % CI - 0·52, - 0·23) and BMI in boys (β = - 0·39 z-scores, 95 % CI - 0·55, - 0·22). Fat-free mass index was related to the total siblings in girls (β = 0·06 z-scores, 95 % CI - 0·04, 0·17). This research has found that number of total siblings, and not birth order, is related to the fat mass index, fat-free mass index and BMI in adolescents. It suggests the need for early prevention of obesity or fat mass accumulation in only children.
Full-text · Article · Jun 2015 · The British journal of nutrition
[Show abstract][Hide abstract] ABSTRACT: Objective:
To evaluate the effect of total breastfeeding, breastfeeding duration and type of breastfeeding at 3 months of age on bone mass at 18 and 30 years.
A prospective, longitudinal study was conducted with two birth cohorts (1982 and 1993) in Pelotas, Southern Brazil. Measurements of bone mineral content (BMC) and bone mineral density (BMD) at 18 and 30 years of age were obtained by dual-energy X-ray absorptiometry (DXA). Information on breastfeeding was collected during the first 4 years of life. Analyses were performed by linear regression and stratified by sex.
A total of 1109 and 3226 participants provided complete information on breastfeeding in early life and bone mass at 18 and 30 years, respectively. No association between breastfeeding and bone mass was observed in women at both ages nor among men at age 30. Among men at the age of 18, BMC and BMD were higher among those breastfed regardless of duration (p=0.032 and p=0.043, respectively).
Despite a very weak positive effect of breastfeeding (yes/no) on BMC and BMD at age 18 in men, most findings pointed to a lack of association between breastfeeding and bone mass until young adulthood.
[Show abstract][Hide abstract] ABSTRACT: We investigated whether Body Mass Index (BMI) at 11 years old has a direct effect on bone mass at age 18 operating through alterations to bone growth and development, or whether the association is mediated by concurrent BMI, fat mass (FM), and fat free mass (FFM).
Path analysis was used to explore the association between BMI at age 11 and whole-body bone mineral content (BMC) and bone mineral density (BMD) assessed by dual-energy x-ray absorptiometry (DXA) at age 18 in a prospective birth cohort study comprising 3,307 adolescents; we also evaluated the degree to which this association was mediated by BMI, FM (kg) and FFM (kg) assessed by plethysmography (BOD POD) at age 18.
We found a positive association between BMI at age 11 and BMC (males [β = 179.7 g, 95% CI 161.4; 198.0]; females [β = 179.9 g, 95% CI 165.3; 194.6]) and BMD (males [β = 0.030 g/cm2, 95% CI 0.024; 0.035]; females [β = 0.029 g/cm2, 95% CI 0.025; 0.033]) at age 18. This association was largely mediated by BMI and FFM at age 18 in both female and male adolescents. FM at age 18 was not an important mediator.
Concurrent BMI and FFM were the main mediators of the association between BMC/BMD in late adolescence and BMI in early adolescence.
Full-text · Article · Mar 2015 · BMC Musculoskeletal Disorders
[Show abstract][Hide abstract] ABSTRACT: To assess the prevalence of sexual initiation until the age of 14 years old, as well as sociodemographic and behavioral factors.
In 2008, 4,325 from the 5,249 adolescents of the 1993 birth cohort in Pelotas, Rio Grande do Sul, were interviewed. Sexual initiation was defined as the first intercourse up to the age of 14 years old. The information was obtained by interviewing adolescents in their houses, during the 2008 follow-up. The analyzed variables were: skin color, asset index, maternal and adolescents' schooling, experimental use of tobacco and alcohol, drunkenness episode, use of any illicit drug, illegal drug use by friends and involvement in fights during the past year. Use of condoms and contraceptive methods, number of partners and the age of sexual initiation were also analyzed.
The prevalence of sexual initiation by the age of 14 was of 18.6%. Lower schooling, asset index and maternal education were related to higher prevalence of sexual initiation until the age of 14, as well as being male or being born to adolescent mothers. Sexual intercourse was also related to the behavioral variables analyzed. Among adolescent girls who had intercourse up to the age of 14, 30% did not use contraception and 18% did not use condoms in the last sexual intercourse. Boys reported a higher number of sexual partners than girls.
The results suggest a relationship between sexual intercourse (≤ 14 years) and some health-risk behaviors. The non-use of condoms and contraceptives may make them vulnerable to experiencing unwanted situations. Education and sociocultural strategies for health should be implemented from the beginning of adolescence.
Full-text · Article · Mar 2015 · Revista Brasileira de Epidemiologia
[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE
To analyze physical activity during adolescence in participants of the 1993 Pelotas Birth Cohort Study, Brazil.
Data on leisure time physical activity at 11, 15, and 18 years of age were analyzed. At each visit, a cut-off point of 300 min/week was used to classify adolescents as active or inactive. A total of 3,736 participants provided data on physical activity at each of the three age points.
A significant decline in the proportion of active adolescents was observed from 11 to 18 years of age, particularly among girls (from 32.9% to 21.7%). The proportions of girls and boys who were active at all three age points were 28.0% and 55.1%, respectively. After adjustment for sex, economic status, and skin color, participants who were active at 11 and 15 years of age were 58.0% more likely to be active at 18 years of age compared with those who were inactive at 11 and 15 years of age.
Physical activity declined during adolescence and inactivity tended to track over time. Our findings reinforce the need to promote physical activity at early stages of life, because active behavior established early tends to be maintained over time.
Full-text · Article · Dec 2014 · Revista de Saúde Pública
[Show abstract][Hide abstract] ABSTRACT: Background:
Maternal smoking during pregnancy is associated with short-term and also long-term harmful effects on offspring.
The aim of this study is to evaluate the associations of maternal smoking during pregnancy with offspring bone health at 18years old, and the role of birth weight and contemporaneous height, weight and body mass index (BMI) in this association. Data from the 1993 Pelotas Birth Cohort were analyzed using path analysis stratified by sex. Adolescents at 18 years old (N=1512 males, 1563 females). DXA-determined total body bone mineral density (BMD) and bone mineral content (BMC) were assessed at 18 years old.
Each additional cigarette smoked during pregnancy was associated with a lower BMC by -4.20 g in males (95% CI -8.37; -0.05), but not in females [-2.22 g (95% CI -5.49; 1.04)]; weaker inverse associations were observed for BMD. This inverse association was explained by the influence of maternal smoking on birth weight and contemporaneous anthropometry, particularly height. A 1 kg higher birth weight was associated with a higher BMC by around 144 g in males and by around 186 g in females, and also with a higher BMD by around 0.019 g/cm(2) in males and by around 0.018 g/cm(2) in females, respectively.
Lifecourse analysis using path models has enabled to evaluate the role of mediators in the associations of maternal smoking during pregnancy and birth weight with bone mass in the offspring, thus generating improved understanding of the etiology of bone health and the importance of early life experiences.
Full-text · Article · Dec 2014 · Early Human Development
[Show abstract][Hide abstract] ABSTRACT: Previous studies have suggested an association between maternal smoking during pregnancy and asthma symptoms such as wheezing during childhood. However, few have evaluated this association in adolescence, especially in populations with high prevalence of wheezing as in Brazil. Using the 1993 Pelotas birth cohort, a longitudinal study set in southern Brazil of 5249 urban live births, we aimed to evaluate the association between maternal and the partner’s smoking during pregnancy and wheezing at 11 and 15 years of age. We evaluated smoking during pregnancy using number of cigarettes/day, and our main outcomes were as follows: wheezing in the last year and number of wheezing crises, at both 11 and 15 years of age, as well as persistent wheezing (having crises at 11 and 15 years of age) and medical asthma diagnosis at age 15. In addition, other socio-demographic variables were included as possible confounders and mediators of this association. We used Poisson regression models to evaluate crude and adjusted associations. Of the 5249 live births in 1993, 87.5% and 85.7% were followed-up to 11 and 15 years of age, respectively. Maternal smoking during pregnancy showed a dose-response association with number of wheezing crises at age 15 (
=0.023), presence of persistent wheezing (
=0.034) and asthma diagnosis (
=0.023). Partner’s smoking was not associated with any wheezing variables. Maternal smoking during pregnancy appears to exert an effect on respiratory morbidity of adolescents, evaluated by wheezing symptoms.
Full-text · Article · Nov 2014 · Journal of Developmental Origins of Health and Disease
[Show abstract][Hide abstract] ABSTRACT: Aim:
To evaluate the longitudinal association between physical activity behavior at 11 years of age and the incidence of mental health problems from 11 to 15 years of age.
Individuals born in the city of Pelotas, Brazil, in 1993 have been followed up since birth. At 11 and 15 years of age, mental health was assessed using the Strengths and Difficulties Questionnaire (SDQ). At 11 years of age, physical activity was assessed through a validated questionnaire. The continuous SDQ score at 15 years was used as the outcome variable. The main exposure was physical activity behavior at 11 years of age divided into 3 categories (0, 1-299, ≥ 300 min/wk).
The incidence of mental health problems from 11 to 15 years was 13.6% (95% CI, 12.4-14.9). At 11 years, 35.2% of the adolescents achieved 300 min/wk of physical activity. In the unadjusted analysis, physical activity was inversely related to mental health problems (P = .04). After adjustment for confounders, the association was no longer significant in the whole sample but was still significant among boys.
Physical activity appears to be inversely related to mental health problems in adolescence, but the magnitude of the association is weak to moderate.
Full-text · Article · Oct 2014 · Journal of physical activity & health
[Show abstract][Hide abstract] ABSTRACT: Purpose:
Most children live in low- and middle-income countries (LMICs), many of which have high levels of violence. Research in high-income countries (HICs) shows that childhood behaviour problems are important precursors of crime and violence. Evidence is lacking on whether this is also true in LMICs. This study examines prevalence rates and associations between conduct problems and hyperactivity and crime and violence in Brazil and Britain.
A comparison was made of birth cohorts in Brazil and Britain, including measures of behaviour problems based on parental report at age 11, and self-reports of crime at age 18 (N = 3,618 Brazil; N = 4,103 Britain). Confounders were measured in the perinatal period and at age 11 in questionnaires completed by the mother and, in Brazil, searches of police records regarding parental crime.
Conduct problems, hyperactivity and violent crime were more prevalent in Brazil than in Britain, but nonviolent crime was more prevalent in Britain. Sex differences in prevalence rates were larger where behaviours were less common: larger for conduct problems, hyperactivity, and violent crime in Britain, and larger for nonviolent crime in Brazil. Conduct problems and hyperactivity predicted nonviolent and violent crime similarly in both countries; the effects were partly explained by perinatal health factors and childhood family environments.
Conduct problems and hyperactivity are similar precursors of crime and violence across different social settings. Early crime and violence prevention programmes could target these behavioural difficulties and associated risks in LMICs as well as in HICs.
Full-text · Article · Oct 2014 · Social Psychiatry and Psychiatric Epidemiology
[Show abstract][Hide abstract] ABSTRACT: Objective
Estimate the prevalence of dental caries based on clinical examinations and self-reports and compare differences in the prevalence and effect measures between the two methods among 18-year-olds belonging to a 1993 birth cohort in the city of Pelotas, Brazil.
Data on self-reported caries, socio-demographic aspects and oral health behaviour were collected using a questionnaire administered to adolescents aged 18 years (n = 4041). Clinical caries was evaluated (n = 1014) by a dentist who had undergone training and calibration exercises. Prevalence rates of clinical and self-reported caries, sensitivity, specificity, positive and negative predictive values, absolute and relative bias, and inflation factors were calculated. Prevalence ratios of dental caries were estimated for each risk factor.
The prevalence of clinical and self-reported caries (DMFT>1) was 66.5% (95%CI: 63.6%–69.3%) and 60.3% (95%CI: 58.8%–61.8%), respectively. Self-reports underestimated the prevalence of dental caries by 9.3% in comparison to clinical evaluations. The analysis of the validity of self-reports regarding the DMFT index indicated high sensitivity (81.8%; 95%CI: 78.7%–84.7%) and specificity (78.1%; 95%CI: 73.3%–82.4%) in relation to the gold standard (clinical evaluation). Both the clinical and self-reported evaluations were associated with gender, schooling and self-rated oral health. Clinical dental caries was associated with visits to the dentist in the previous year. Self-reported dental caries was associated with daily tooth brushing frequency.
Based on the present findings, self-reported information on dental caries using the DMFT index requires further studies prior to its use in the analysis of risk factors, but is valid for population-based health surveys with the aim of planning and monitoring oral health actions directed at adolescents.