Uric acid is independent and inversely associated to glomerular filtration rate in young adult Brazilian individuals.

BACKGROUND AND AIMS: Uric acid, the end-product of human purine metabolism, is associated with hypertension, diabetes and obesity. It has also been independently associated with the onset of chronic kidney disease in several populations. In this study, the association between serum uric acid (SUA) level and estimated glomerular filtration rate (eGFR) was investigated in healthy individuals belonging to two Brazilian birth cohorts. METHODS AND RESULTS: Data from 3541 to 3482 individuals, aged 30 and 22-years old, respectively, was included. eGFR was calculated using Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation based on creatinine measurement. Regression analyses were sex-stratified due to interaction between SUA and sex (p < 0.001) and adjusted for perinatal, cardiometabolic and behavioral variables. We observed an inverse association between eGFR and SUA even after adjustment. In the highest tertile (3rd) of SUA, the eGFR coefficients at 30-years were-0.21 (95%CI -0.24;-0.18) for men and -0.20 (95%CI -0.23; -0.17) for women; at 22-years, were -0.09 (95%CI -0.12;-0.05) for men and -0.13 (95%CI -0.15; -0.10) for women. Higher differences among exponential means (95% CI) of eGFR between the 1st and the 3rd tertile of SUA were seen in older participants, being more pronounced in men. At 22-years, the highest difference was found in women. CONCLUSIONS: In young healthy individuals from a low-middle income country, SUA level was inversely associated with eGFR. Gender-related differences in eGFR according tertiles of SUA were higher in men at 30-years and in women at 22-years.

Age at menarche associated with subsequent educational attainment and risk-taking behaviours: the Pelotas 1982 Birth Cohort.

Background: Earlier age at menarche (AAM), a marker of puberty timing in females, has been associated with a higher likelihood of adolescent risk-taking behaviours and variably associated with educational attainment.Aim: To examine the association between AAM and educational attainment in the Pelotas, Brazil, 1982 Birth Cohort.Subjects and methods: AAM was categorised as Early (7-11 years), Average (12-13 years), or Late (14+ years). Primary outcome: years of education (age 30). Secondary outcomes: risk-taking behaviours, adult income and school grade failure.Results: In adjusted models, compared to Average AAM, Late AAM was associated with 0.64 fewer years of education (95% CI: -1.15, -0.13). Early AAM was associated with earlier age at first sexual intercourse (-0.25 years; 95% CI: -0.39, -0.12), whereas Late AAM was associated with 17% lower adult income (0.83; 95% CI: 0.71, 0.95) and 0.31 years older age at first alcohol consumption (95% CI: 0.10, 0.52).Conclusions: Our findings confirm the association between earlier puberty timing in females and a greater likelihood of risk-taking behaviours in this setting of recent secular changes towards earlier puberty. However, the association between Late AAM and lower education was surprising and may support a psychosocial rather than biological link between puberty timing and educational outcomes.

C-Peptide and cardiovascular risk factors among young adults in a southern Brazilian cohort.

BACKGROUND: Proinsulin connecting peptide (C-Peptide) is a marker of the beta-cell function and has been considered a marker of insulin resistance whose evidence suggests were associated with cardiovascular mortality. Our study aims to evaluate the association of C-Peptide with metabolic cardiovascular risk factors among young adults followed since birth in southern Brazil. METHODS: In 1982, maternity hospital in Pelotas, a southern Brazilian city, were visited daily and all births were identified. Live births whose family lived in the urban area of the city were identified, their mothers interviewed, and these subjects have been prospectively followed. Casual hyperglycemia patients were excluded from analysis. C-Peptide was assessed at 23 years, when transversely analyzed its association with cardiometabolic and hemodynamic risk factors, and longitudinally 30 years of age. RESULTS: At age 23, 4297 individuals were evaluated, and C-Peptide was measured in 3.807. In a cross-sectional analysis at 23 years of age, C-Peptide was positively associated with waist circumference, body mass index, glycaemia, triglycerides, and C-reactive protein. The association with HDL cholesterol was negative. In the longitudinal analysis at 30 years, C-Peptide remained associated with BMI, waist circumference, glycated hemoglobin, triglycerides, and C-reactive protein, whereas the association was negative for HDL. CONCLUSION: In the Pelotas birth cohort, the C-Peptide was associated with obesity indicators (waist circumference and BMI) cross-sectional (23 years) and longitudinal (30 years). We also observed cross-sectional and longitudinal associations of C-Peptide with cardiometabolic and inflammatory risk factors.

Effect of life-course family income trajectories on periodontitis: Birth cohort study.

AIMS: To quantify the impact of life course income trajectories on periodontitis in adulthood. MATERIALS AND METHODS: Data from the 1982 Pelotas Birth Cohort Study, Brazil, were used. Information on family income was collected at birth and ages 15, 19, 23 and 30 years. Group-based trajectory modelling was used to identify income trajectories. Periodontal measures were assessed through clinical examination at age 31. Log-Poisson regression models were used to estimate prevalence ratios (PRs) of any and moderate/severe periodontitis, as outcomes. RESULTS: Prevalence of any periodontitis and moderate/severe periodontitis was 37.3% and 14.3% (n = 539). Income trajectories were associated with prevalence of moderate/severe periodontitis. Adjusted PR in participants in low and variable income trajectory was 2.1 times higher than in participants in stable high-income trajectory. The unadjusted association between income trajectories and prevalence of any periodontitis was explained by the inclusion of behavioural and clinical variables in the model. CONCLUSIONS: Low and variable life course income increased the prevalence of moderate/severe periodontitis at age 31 years. The findings may inform programmes in identifying and targeting potentially at-risk groups during the life course to prevent periodontitis.

Diet-Induced Overweight and Obesity and Periodontitis Risk: An Application of the Parametric G-Formula in the 1982 Pelotas Birth Cohort.

We aimed to estimate hypothetical effects of habits (smoking, alcohol consumption, and fat and carbohydrates consumption) combined with diet-induced overweight/obesity on the risk of periodontitis. The risk of any periodontitis, moderate/severe periodontitis, and the combination of bleeding on probing (BOP) and clinical attachment loss (CAL) was estimated using the parametric g-formula in adults aged 31 years from the 1982 Pelotas Birth Cohort in Brazil. Individuals in this cohort have been followed since birth. Hypothetical conditions were set independently for each risk factor and in combination for the entire population. A total of 539 participants had oral examinations in 2013. The cumulative 31-year risk under no intervention was 33.3% for any periodontitis, 14.3%, for moderate/severe periodontitis, and 14.7%, for BOP and CAL. According to our statistical approach, diet-induced overweight/obesity increased the risk of all outcomes: 11% (overweight) and 22% (obesity) higher risk of periodontitis; 12% (overweight) and 27% (obesity) higher risk of moderate/severe periodontitis; 21% (overweight) and 57% (obesity) higher risk of CAL and BOP. When overweight/obesity was combined with other unhealthy habits, the risk was even greater. Our findings suggest that the combination of diet-induced obesity with other risk factors may increase the risk of periodontitis. Further research in the field is required to corroborate our study.

Associations of Linear Growth and Relative Weight Gain in Early Life with Human Capital at 30 Years of Age.

OBJECTIVE: To assess the associations of birthweight, nutritional status and growth in childhood with IQ, years of schooling, and monthly income at 30 years of age. STUDY DESIGN: In 1982, the 5 maternity hospitals in Pelotas, Brazil, were visited daily and 5914 live births were identified. At 30 years of age, 3701 subjects were interviewed. IQ, years of schooling, and income were measured. RESULTS: On average, their IQ was 98 points, they had 11.4 years of schooling, and the mean income was 1593 reais. After controlling for several confounders, birthweight and attained weight and length/height for age at 2 and 4 years of age were associated positively with IQ, years of years of schooling, and income, except for the association between length at 2 years of age and income. Conditional growth analyses were used to disentangle linear growth from relative weight gain. Conditional length at 2 years of age ≥1 SD score above the expected value, compared with ≥1 SD below the expected, was associated with an increase in IQ (4.28 points; 95% CI, 2.66-5.90), years of schooling (1.58 years; 95% CI, 1.08-2.08), and monthly income (303 Brazilian reais; 95% CI, 44-563). Relative weight gain, above what would be expected from linear growth, was not associated with the outcomes. CONCLUSION: In a middle-income setting, promotion of linear growth in the first 1000 days of life is likely to increase adult IQ, years of schooling, and income. Weight gain in excess of what is expected from linear growth does not seem to improve human capital.

Visceral and subcutaneous abdominal adiposity and pulmonary function in 30-year-old adults: a cross-sectional analysis nested in a birth cohort.

BACKGROUND: Several studies have verified body fat distribution in association with pulmonary function (PF), mainly waist circumference, but few have used measures able to distinguish abdominal fat compartments. The present study aims to verify the association of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) with PF measures. METHODS: In 1982, all hospital births occurring in Pelotas, Brazil, were identified and those livebirths have been followed. In 2012-13, the cohort participants were evaluated and VAT and SAT measured using ultrasound; forced expiratory volume in the first second (FEV1) or forced vital capacity (FVC) were patronized in z-scores stratified by sex. The associations were verified using crude and adjusted linear regressions. RESULTS: The present analyses comprised 3438 individuals (1721 women). VAT was inversely associated with spirometric parameters, in both crude and adjusted models. SAT showed inverse associations in the crude analyzes in males and a positive trend after adjustment, except for SAT and FVC in males. To each centimeter of VAT, mean adjusted FEV1 z-scores decreased 0.072 (95% CI -0.107; -0.036) in men and 0.127 (95% CI -0.164; -0.090) in women, and FVC z-scores decreased -0.075 (95% CI -0.111; -0.039) and 0.121 (95% CI -0.158; -0.083), in men and women, respectively. CONCLUSIONS: VAT has a consistent inverse association with FEV1 and FVC in both sexes. On the other hand, SAT showed inconsistent results with PF parameters.

African ancestry, lung function and the effect of genetics.

African-Americans have smaller lung function compared with European-Americans. The aim of this study was to disentangle the contribution of genetics from other variables on lung function. A cohort was followed from birth to 30 years of age in Brazil. Several variables were collected: genomic analysis based on DNA; forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) obtained by spirometry; height measured by anthropometrists; and thorax circumference evaluated by photonic scanner. Crude and adjusted linear regression models were calculated according to African ancestry. The sample comprised 2869 participants out of 3701 members of the cohort. Males with higher African ancestry by DNA analysis had a smaller FEV1 (-0.13 L, 95% CI -0.23- -0.03 L) and FVC (-0.21 L, 95% CI -0.32- -0.09 L) compared with those with less African ancestry, having accounted for height, sitting to standing height ratio and other confounders. Similar effects were seen in females. After adjustment, ancestry remained significantly associated with lung function, but the large effect of adjustment for confounding among males (but not females) does not allow us to exclude the possibility that residual confounding may still account for these findings.

Promotion of Weight Gain in Early Childhood Does Not Increase Metabolic Risk in Adolescents: A 15-Year Follow-Up of a Cluster-Randomized Controlled Trial.

BACKGROUND: A rapid gain in weight for length may put children at a higher risk of noncommunicable diseases later in life. OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Increase in child behavior problems among urban Brazilian 4-year olds: 1993 and 2004 Pelotas birth cohorts.

BACKGROUND: There are an increasing number of reports on time trends in child and adolescent psychological problems but none from low- and middle-income countries, and very few covering the preschool period. The aim was to investigate changes in preschool behavioral/emotional problems in two birth cohorts from a middle-income country born 11 years apart. METHODS: We analyzed data from the 1993 and 2004 Pelotas birth cohort studies from Brazil. A subsample of 4-year olds from the 1993 cohort (634) and all 4-year olds from the 2004 cohort (3750) were assessed for behavioral/emotional problems through maternal report using the Child Behavior Checklist (CBCL). Response rates in these two population-based cohorts were above 90%. RESULTS: We found a significant increase in CBCL total problems, internalizing and externalizing mean scores over the 11-year period. For 1993 and 2004 Pelotas cohorts, respectively, CBCL mean values (SE) total problems scores were 27.9 (0.8) and 34.7 (0.3); for internalizing scores, 5.7 (0.2) and 6.3 (0.1) and for externalizing scores, 12.4 (0.4) and 15.5 (0.1). After adjusting for confounding variables, the largest increase from 1993 to 2004 was identified in the aggressive behavior syndrome score (Cohen's d = .50), followed by the externalizing problem score (Cohen's d = .40) and CBCL total problem score (Cohen's d = .36), respectively. The rise in child psychological problems was more marked in children from families with fewer assets and with less educated mothers. CONCLUSIONS: Our findings provide evidence for a substantial increase in preschool behavioral problems among children in Brazil over an 11-year period.

Physical activity from adolescence to young adulthood and bone mineral density in young adults from the 1982 Pelotas (Brazil) Birth Cohort.

OBJECTIVE: To evaluate a prospective association between physical activity (PA) and bone mineral density (BMD) in young adults. METHOD: Total body (TB), lumbar spine (LS) and femoral neck (FN) BMD were measured in participants from the 1982 Pelotas Birth Cohort by dual-energy X-ray absorptiometry at 30 y. PA was evaluated at 15, 18 (males) and 23 y. RESULTS: 3454 young adults were scanned (DXA) at least at one anatomical site. In males, PA at 15 y was associated with LS density (ß=0.061 g/cm(2); 95% confidence interval (CI): 0.015; 0.108). A positive dose-response effect was found for the association between PA at 18 y and BMD. Males in the two highest quartiles of PA at 23 y had significantly greater BMD at all anatomical sites than males in the lowest quartile. We observed greater BMD at 30 y in boys who were active at least in one of the assessments (18 or 23 y) compared to inactive boys at both ages. Females in the highest quartile of PA at 23 y showed greater FN density at 30 y (ß=0.020; 95%CI: 0.001; 0.039). CONCLUSIONS: A physically active pattern is important to BMD across the first three decades of life. Potential beneficial effects of PA were not entirely lost with advancing age in male young adults.

Maternal height and child growth patterns.

OBJECTIVE: To examine associations between maternal height and child growth during 4 developmental periods: intrauterine, birth to age 2 years, age 2 years to mid-childhood (MC), and MC to adulthood. STUDY DESIGN: Pooled analysis of maternal height and offspring growth using 7630 mother-child pairs from 5 birth cohorts (Brazil, Guatemala, India, the Philippines, and South Africa). We used conditional height measures that control for collinearity in height across periods. We estimated associations between maternal height and offspring growth using multivariate regression models adjusted for household income, child sex, birth order, and study site. RESULTS: Maternal height was associated with birth weight and with both height and conditional height at each age examined. The strongest associations with conditional heights were for adulthood and 2 years of age. A 1-cm increase in maternal height predicted a 0.024 (95% CI: 0.021-0.028) SD increase in offspring birth weight, a 0.037 (95% CI: 0.033-0.040) SD increase in conditional height at 2 years, a 0.025 (95% CI: 0.021-0.029 SD increase in conditional height in MC, and a 0.044 (95% CI: 0.040-0.048) SD increase in conditional height in adulthood. Short mothers (<150.1 cm) were more likely to have a child who was stunted at 2 years (prevalence ratio = 3.20 (95% CI: 2.80-3.60) and as an adult (prevalence ratio = 4.74, (95% CI: 4.13-5.44). There was no evidence of heterogeneity by site or sex. CONCLUSION: Maternal height influences offspring linear growth over the growing period. These influences likely include genetic and non-genetic factors, including nutrition-related intergenerational influences on growth that prevent the attainment of genetic height potential in low- and middle-income countries.

Association of family income with BMI from childhood to adult life: a birth cohort study.

OBJECTIVE: To investigate the association of family income at birth with BMI among young adults who have been followed since birth. DESIGN: A birth cohort study. SETTING: In 1982, all children born in Pelotas, southern Brazil, were included in a perinatal survey and visited at ages 1, 2, 4, 15, 18-19 and 23 years. SUBJECTS: Cohort members (n 4297) were traced and interviewed in 2004-2005. In all follow-ups, participants were weighed and measured, and BMI and prevalence of obesity were calculated for each age. Family income was obtained in minimum wages in 1982 and as a continuous variable, in reais, in later follow-ups. Skin colour was self-reported in 2004-2005. RESULTS: Mean BMI and prevalence of obesity differed between males and females. In males, a direct relationship was found throughout life and among females this relationship was modified by age. During childhood, BMI was higher among girls from higher income groups and this association was inversed at age 23 years. At this same age, mean BMI among black women was 1·3 kg/m2 higher than among white women, even after adjustment for current family income. CONCLUSIONS: The findings show in men that the relationship between income and BMI is similar to that seen in less developed areas, whereas among adult women the relationship is similar to that observed in developed countries. In addition to the effect of socio-economic status, skin colour also has an influence on the BMI of adult women.

Major dietary patterns and cardiovascular risk factors among young Brazilian adults.

PURPOSE: Diet is one of the most important modifiable risk factors for cardiovascular diseases. The scientific literature has consistently shown the effects of certain diets on health; however, given the variety of cultures and dietary habits across the world, it is likely that much remains to be learned about dietary patterns and health outcomes. We assessed the associations between main dietary patterns and cardiovascular risk factors among 4,202 young Brazilian adults in a cross-sectional analysis. METHODS: In a principle components analysis, two main dietary patterns were identified: common Brazilian and processed food. As outcomes, we examined body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol, HDL cholesterol (HDL-c), and LDL cholesterol (LDL-c). Means, crude, and adjusted ß coefficients and 95% CIs were estimated according to quintiles of dietary patterns. RESULTS: Common Brazilian scores were inversely associated with BMI, WC, LDL-c, HDL-c, and total cholesterol values among men. Among women, inverse association trends were observed with SBP, DBP, LDL-c, HDL-c, and total cholesterol. The processed food pattern was positively associated with LDL-c, HDL-c, total cholesterol, BMI, and WC values among the men. Among the women, the processed food pattern was not significantly associated with cardiovascular risk factors. CONCLUSIONS: In conclusion, our findings confirm that diet has an important role on health during early adulthood. The common Brazilian pattern showed generally healthier trends regarding CVD risk factors, but the ultimate effects on risk of risk of disease are unclear because of the inverse relation with HDL-c levels.

Flour fortification with iron has no impact on anaemia in urban Brazilian children.

OBJECTIVE: To verify the impact of flour fortification on anaemia in Brazilian children. The survey also investigated the role of Fe deficiency as a cause of anaemia and estimated the bioavailability of the Fe in the children's diet. This local study was complemented by a nationwide survey of the types of Fe compounds added to flour. DESIGN: Series of population-based surveys conducted in 2004 (baseline study), 2005, 2006 and 2008. SETTING: Pelotas, Rio Grande do Sul, Brazil. SUBJECTS: Children under 6 years of age residing in the urban area of the city of Pelotas, Southern Brazil (n 507 in 2004; n 960 in 2005; n 893 in 2006; n 799 in 2008). In 2008, a sub-sample of children (n 114) provided venous blood samples to measure body Fe reserve parameters (ferritin and transferrin saturation). RESULTS: We found no impact of fortification, with an increase in anaemia prevalence among children under 24 months of age. Hb levels decreased by 0.9 g/dl in this age group between 2004 and 2008 (10.9 g/dl to 10.0 g/dl; P < 0.001). Roughly 50 % of cases of anaemia were estimated to be due to Fe deficiency. Half of the mills surveyed used reduced Fe to fortify wheat flour. Total Fe intake from all foodstuffs was adequate for 88.6 % of the children, but its bioavailability was only 5 %. CONCLUSIONS: The low bioavailability of the Fe compounds added to flours, combined with the poor quality of children's diets, account for the lack of impact of mandatory fortification.

Predictors of physical activity change during adolescence: a 3.5-year follow-up.

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.

Trends in socioeconomic inequalities in anthropometric status in a population undergoing the nutritional transition: data from 1982, 1993 and 2004 Pelotas birth cohort studies.

BACKGROUND: Socioeconomic inequalities in child nutrition may change rapidly over time, particularly in populations undergoing the nutrition transition. Yet, the few available studies are repeated cross-sectional surveys. By studying three prospective birth cohorts in the same city over a period of more than two decades, we describe secular trends in overweight and stunting at different ages, according to socioeconomic position. METHODS: Population-based birth cohort studies were launched in the city of Pelotas (Brazil) in 1982, 1993 and 2004, with follow-up visits at twelve, 24 and 48 months. Children were weighed and measured at every visit. Z-scores of length/height-for-age and body mass index-for-age were calculated using the WHO Child Growth Standards. The slope and relative indices of inequality, based on family income quintiles, were estimated for each follow-up visit. RESULTS: Between the 1982 and 2004 cohorts, stunting among four-year-olds declined (from 10.9% to 3.6%), while overweight increased (from 7.6% to 12.3%). In every visit, stunting prevalence was inversely related to income. Both absolute and relative inequalities declined over time; among four-year-olds stunting dropped from 26.0% in the 1982 cohort to 6.7% in the 2004 cohort in the poorest group, while in the richest group stunting prevalence dropped from 2.7% in 1982 to 1.1% in the 2004 cohort study. The secular trend towards increased overweight was evident for four-year-olds, in almost all socioeconomic groups, but not among one and two-year-olds. Among four-year old children, overweight prevalence increased in all income quintiles, by 130% in the middle-income group, 64% in the poorest and 41% in the richest group. CONCLUSIONS: The decline in stunting is remarkable, but the increase in overweight among four-year olds - particularly among the poorest and the middle-income groups- requires concerted efforts to prevent the long term consequences of child overweight.

A longitudinal evaluation of physical activity in Brazilian adolescents: tracking, change and predictors.

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.

The influence of family income trajectories from birth to adulthood on adult oral health: findings from the 1982 Pelotas birth cohort.

OBJECTIVES: We assessed whether 3 models of life course socioeconomic status (critical period, accumulation of risk, and social mobility) predicted unsound teeth in adulthood among a Brazilian cohort. METHODS: Life course data were collected on the 5914 live-born infants in the 1982 Pelotas Birth Cohort study. Participants' oral health was assessed at 15 (n = 888) and 24 (n = 720) years of age. We assessed family income trajectories and number of episodes of poverty in the life course through Poisson regressions, yielding unadjusted and adjusted prevalence ratios for number of unsound teeth at age 24 years. RESULTS: The adjusted prevalence ratio for participants born into poverty was 30% higher than for those who were not. Participants who were always poor had the highest prevalence of unsound teeth; those who were downwardly or upwardly mobile also had more unsound teeth than did other participants, after adjustment for confounders. More episodes of poverty were associated with greater prevalence of unsound teeth in adulthood. CONCLUSIONS: Poverty at birth and during the life course was correlated with the number of unsound teeth at 24 years of age.

Validation of the Netherlands physical activity questionnaire in Brazilian children.

BACKGROUND: Physical activity instruments can be subjective or objective. There is a need to assess the reliability of these instruments, especially for researches in children. The aim of this study was to determine the validity of the Netherlands Physical Activity Questionnaire (NPAQ). METHODS: Population under study were Brazilian children aged 4 to 11 years old, enrolled in a population-based study. Data collection took place in two distinct moments: 1) application of the NPAQ by face-to-face interviews with mothers' children and 2) utilization of accelerometers by children as the reference method. GT1M Actigraph accelerometer was worn for five consecutive days. Validity analyses were performed by sensitivity and specificity and ROC (Receiver Operator Characteristic) curve. RESULTS: Two hundred and thirty nine children participated in both phases of the study. A total of 73.2% children achieved the recommendation of 60 min/day of moderate to vigorous physical activity. The mean and median of the NPAQ score were 25.5 and 26, respectively. The score ranged from 7 to 35 points. The correlation coefficient between the NPAQ and the time spent in moderate to vigorous physical activities was 0.27. Based on the area under the ROC curve, the median value presented the best indicators of sensitivity (59.4%) and specificity (60.9%), and the area under curve was 0.63. The predictive capacity of the NPAQ to identify active children was high regardless the cut-off point chosen. This capacity was even higher if the score was higher than 30. CONCLUSIONS: Based on sensitivity and specificity values, the NPAQ did not show satisfactory validity. The comparison of the reliability of the NPAQ with other instruments is limited, but correlation coefficients found in this study are similar to others. Physical activity level of children estimated from the NPAQ must be interpreted cautiously, and objective measures such as accelerometers should be encouraged.