Vitor Rosado

Prevalence and risk factors for overweight and obesity in Portuguese children.

Aim: To identify risk factors for overweight and obesity in Portuguese children.

Maternal weigh gain during pregnancy and overweight in Portuguese children

Objective:The objective of our study was to assess the association between maternal weight gain during pregnancy and childhood overweight.Design:This study was a cross-sectional analysis.Setting:The data were derived from a community-based survey of children from primary schools of Portugal.Subjects:The study was performed in a sample of 6-12-year-old Portuguese school children (2445 girls and 2400 boys; age was 8.5±0.91 years).Measurements:Height and weight were measured according to international standards, and body mass index (BMI) was calculated. The definition of overweight was based on average centiles according to the International Obesity Task Force cutoffs. Childrens parents completed a self-administered questionnaire, which provided information on general family background characteristics, maternal weight gain during pregnancy and childrens physical activity. The response rate was 70.6%. Childrens dietary intake was measured using a 24-h dietary recall. Logistic regression models were fitted to estimate the magnitude of the association between maternal weight gain during pregnancy and overweight in their children, adjusting for confounders (gender, age, birthweight, order of birth, breastfeeding, smoking during pregnancy, physical activity, parental BMI, parental education, calcium to protein ratio and energy intake).Results:The prevalence of overweight (including obesity) was 29% in boys and 33% in girls. The odds favouring overweight (including obesity) increased significantly for those women who gained ⩾16 kg during pregnancy, compared to those with <9 kg , even after adjustment for confounders (crude odds ratio (OR)=1.53, confidence interval (CI) 95% 1.27–1.84, P-trend <0.001; Adjusted OR=1.27, CI 95% 1.01–1.61, P-trend=0.038).Conclusion:Large maternal weight gain during pregnancy (⩾16 kg) was significantly associated with higher risk of overweight in Portuguese children.

Parent and Child Screen-Viewing Time and Home Media Environment

BACKGROUND Screen-viewing time has been associated with adverse health outcomes. Data on the predictors of youth screen-viewing time is predominately from older children in North America. Parental and home media environment factors that are associated with screen-viewing time could be targeted in interventions. PURPOSE Examine if parental screen-viewing time and electronic media (access to game equipment, TVs, PCs, and laptops) environment factors were associated with Portuguese childrens screen-viewing time and if associations differed by child age (<7 vs ≥7 years); gender; or type of screen viewing. METHODS Data are reported for 2965 families with children aged 3-10 years. Data were collected in 2009-2010 and analyzed in 2011. Outcomes were child spending ≥2 hours watching TV and ≥1 hour per day playing with combined other media. Exposures were mothers and fathers watching ≥2 hours of TV and electronic media variables. RESULTS Parental TV-viewing time was strongly associated with child weekday and weekend TV-viewing time across all four gender and age subgroups. Maternal TV-viewing time was a stronger predictor of child TV-viewing time than paternal TV-viewing time. There was very limited evidence that parental TV-viewing time was associated with combined other media time among boys or girls. Access to electronic game equipment increased the likelihood that children spent >1 hour using combined other media on weekdays and weekend days. CONCLUSIONS Parental TV-viewing time was associated with Portuguese childrens TV-viewing time. The numbers of TVs in the household and electronic games equipment access were also associated with TV- and combined other media-viewing/usage time.

Dietary calcium and body mass index in Portuguese children

Objective:The objective of our study was to assess nutritional intake in school children (7–9-y-old) and relate calcium intake to body mass index (BMI).Design:This study was a cross-sectional analysis.Setting:The data were derived from a community-based survey of children from primary schools of Portugal.Subjects:In all, 3044 Portuguese children (1503 girls and 1541 boys) from a community-based sample of 7–9-y-olds.Methods:Height and weight were measured according to international standards, and BMI was calculated. Childrens parents completed a self-administered questionnaire that provided information on general family background characteristics and childrens physical activity. Childrens dietary intake was measured using a 24-h dietary recall. Calcium intake was expressed as the calcium-to-protein ratio, and regression analysis was used to estimate the association between calcium intake and BMI, adjusting for energy intake and confounders.Results:The prevalence of children with calcium intake below the Dietary Reference Intake was higher in girls (36.4 vs 33.0%, P=0.053). Calcium-to-protein ratio predicts BMI only in girls (β=−0.052, P=0.002), even after adjusting for age, energy intake, parental education, and physical activity.Conclusion:We found an inverse relationship between calcium intake and BMI only in girls. These data reinforce the need for controlled trials to assess the effects of dietary calcium on body mass in each gender.Sponsorship:Fundação Ciência e Tecnologia POCTI/ESP/43238/2001.

Type-specific screen time associations with cardiovascular risk markers in children

BACKGROUND There is evidence that TV time may have stronger associations with cardiovascular risk markers than other types of screen time, but most studies focus on TV, or total screen time. PURPOSE To examine associations between types of screen time and cardiovascular risk markers in school-age children. METHODS Cross-sectional study of 2515 school children in Portugal (aged 2-12 years, data collected in 2009 and 2010). Three types of screen time (TV, electronic games, and PC time) were collected through a questionnaire, and data on three cardiovascular risk markers (resting heart rate; diastolic blood pressure [DBP]; and systolic blood pressure [SBP]) were collected by a trained fieldworker. Complex-samples generalized linear models were run for each combination of screen time predictor and cardiovascular risk outcome, and a clustered cardiovascular risk score, adjusting for potential confounders (including physical activity). Analyses were conducted in 2011 and 2012. RESULTS TV viewing, but not PC or electronic games time, was associated positively with clustered cardiovascular risk score, DBP, and SBP after adjustment for all covariates. Watching TV for >2 hours/day (compared to <1 hour/day) was associated with higher DBP (coefficient, logged and back-transformed 0.02, 95% CI=0.00, 0.04, linear trend p=0.003); SBP (logged and back-transformed 0.02, 95% CI= -0.01, 0.05, p=0.009), and clustered cardiovascular risk score (0.13, 95% CI=0.02, 0.24, p<0.001). CONCLUSIONS TV viewing, but no other type of screen time, was associated positively with cardiovascular risk markers independently of physical activity. Studies using a single marker of screen time or sedentary behavior may conceal screen time type-specific associations.

Associations between indicators of screen time and adiposity indices in Portuguese children.

OBJECTIVES To examine associations between three types of screen time (TV, electronic games (EG), and personal computer (PC)) and two proxies of adiposity (body mass index (BMI) and sum of skinfolds) in children. DESIGN The sample comprised 17,509 children aged 2-13 years who participated in the 2009/10 Portuguese Prevalence Study of Obesity in Childhood. METHODS Complex samples generalised linear models, using school as a cluster variable were ran separately for each combination of ST predictor and adiposity-related outcome, adjusting for covariates including age, sex, physical activity, diet, and parental factors. Missing values in predictors and covariates were imputed. RESULTS Watching TV for >2h/day compared to <1h/day was associated with higher age- and sex-specific BMI standard deviation score (coefficient: 0.06, 95% CI: 0.01 to 0.12, linear trend p=0.008) and sum of skinfolds (logged and back transformed 0.04, 0.02 to 0.07, p=<0.001). We also found weak evidence for an inverse association between PC and BMI. CONCLUSIONS Associations between ST and adiposity differ by both type of ST and type of adiposity marker. Only TV viewing was consistently associated with adiposity. Studies using a single adiposity marker looking at total screen time or total sedentary behaviour time may miss or confound type-specific associations.