Generation XXI Birth Cohort Research Articles

Association of dietary macronutrient intake with adiposity during childhood according to sex: Findings from the generation XXI birth cohort.

Few studies have assessed the independent and longitudinal effects of each macronutrient intake on adiposity throughout childhood. We aimed to prospectively assess the independent associations between each macronutrient intake at 4, 7, and 10 years (protein, carbohydrates, fat, and fibre) and each measure of adiposity from 7 to 10 years of age by sex. Data from the population-based birth cohort Generation XXI was used (n=3999). At 4, 7, and 10 years old, dietary, anthropometric and sociodemographic data were collected. The dietary intake of the children was evaluated by a validated food frequency questionnaire. Age- and sex-specific body mass index z-scores (zBMI), percentage of body fat (%FM) from bio-impedance, and waist-to-hip ratio (Whr) were used as measures of adiposity. Path analysis tested the independent associations between each macronutrient intake (protein, carbohydrates, fat, and fibre) and each measure of adiposity from 7 to 10 years of age. In fully adjusted models, an increase in energy from fibre intake at the age of 7 was associated with lower zBMI at the same age (β=-0.073; 95%CI [-0.127,-0.019]) and at 10 years (β=-0.083; 95%CI [-0.137,-0.029]). Similar results were found for %FM and Whr, and in each sex separately. At the age of 10, an increase in energy from fibre intake was associated with lower %FM and Whr, while an increase in energy from protein was associated with an increase in Whr (β=0.061; 95%CI [0.014, 0.107]). Our study supports the protective effect of fibre intake on adiposity development during childhood in both sexes.

Persistent weight gain between 0 and 4 years of age is associated with higher dehydroepiandrosterone sulphate levels at 7 years old: Data from the Generation XXI birth cohort.

To assess the influence of longitudinal weight gain from 0 to 4 years old on dehydroepiandrosterone sulphate (DHEAS) levels at 7 years old. DHEAS levels were measured at 7 years old in a subsample of 587 children from the Generation XXI birth cohort. Weight trajectories (0-4 years of age) were identified using model-based clustering and categorized as "normal weight gain,""weight gain during infancy,""weight gain during childhood" and "persistent weight gain." Differences in DHEAS levels at age 7 between the four weight trajectories were analysed through analysis of covariance (ANCOVA), adjusted for birth weight (BW) and body mass index (BMI). In the crude analysis, compared with the "normal weight gain" trajectory (5.53 (95% CI: 5.10-5.98]µmol/L), DHEAS levels were significantly higher in children in the "persistent weight gain" (8.75 [95% CI: 7.23-10.49] µmol/L, p < .001] and in children in the "weight gain during infancy" trajectories (7.68 [95% CI: 6.22-9.49] µmol/L, p = .021]and marginally significantly higher in children in the "weight gain during childhood" trajectory (6.89 (95% CI: 5.98-8.00) µmol/L; p = .052). In BW- and BMI-adjusted model, a statistically significant difference in DHEAS levels was found between the "persistent weight gain" (7.93 [95% CI: 6.43-9.86] µmol/L) and the "normal weight gain" trajectories ([5.75 [95% CI: 5.32-6.23] µmol/L; p = .039). Higher DHEAS levels are found in 7-year-old children following a trajectory of persistent weight gain from 0 to 4 years, independently of their BW or current BMI, highlighting the impact of exposure to overweight in the first years of life on prepubertal adrenal androgen production.

Association between Land Use Mix and Respiratory Symptoms and Asthma in Children from the Generation XXI Birth Cohort.

Land use mix (LUM) in the neighbourhoods has been associated with healthier lifestyles. However, less is known about the association between LUM and health outcomes, namely during childhood. The objective of this study was to evaluate the association between different LUM indexes for Porto Metropolitan Area and asthma and respiratory symptoms in children. A cross-sectional analysis was performed involving 6260 children enrolled in Generation XXI. Land use around the child's residence was assessed with the Portuguese official map of land cover using a GIS. Generalized linear mixed-effects models were fitted to estimate the association between LUM and respiratory symptoms and asthma at 7years of age. Adjusted associations were quantified using odds ratio (OR) and 95% confidence interval (95% CI). After adjustment, LUM was associated with a lower odds of wheezing in the last 12months [OR (95% CI) = 0.37 (0.15; 0.93) using Shannon's Evenness Index within 500m; and OR = 0.93 (0.89; 0.98) using the number of different land use types within 250m]. Living in neighbourhoods with high LUM has a protective effect on current wheezing symptoms. Our results highlight the association between LUM and respiratory symptoms among children, suggesting that public health considerations should be incorporated in land use decision-making.

Association of early feeding practices with dietary patterns of 7-year-olds from the birth cohort Generation XXI

Early feeding practices have been related to child's body mass index (BMI), however, their role in establishing dietary patterns is less well understood. The aim of this study was to examine the association of parent-reported early feeding practices (breastfeeding duration, type of foods and timing of complementary feeding) and dietary patterns identified at age 7 to explain BMI z-scores at 10 years of age. Participants were children from the Generation XXI cohort, evaluated at 4, 7 and 10 years of age (n = 3673). At 7 years-old, dietary intake was assessed with a validated food-frequency questionnaire. Two dietary patterns were previously derived: “Energy-dense foods” (higher in energy-dense foods, and lower in vegetable soup, significantly associated with BMI z-score at 10 years-old, and the “Fish-based” dietary pattern (higher in fish consumption and low in energy-dense foods). Adjusted sex-stratified associations were estimated by generalized linear models. Boys and girls who were never breastfed or were breastfed for a very short duration had lower scores in the “Fish-based” dietary pattern, compared to those with longer breastfeeding durations (Boys: β = −0.219; 95%CI: 0.361; −0.077; Girls: β = −0.223; 95%CI: 0.358; −0.088). No significant associations between breastfeeding and the “Energy-dense foods” dietary pattern were found. Boys and girls who were offered cereals as a first food during complementary feeding, in comparison with soup, presented lower scores in the “Energy-dense foods” dietary pattern (Boys: β = −0.183; 95%CI: 0.292; −0.074; Girls: β = −0.155; 95%CI: 0.259; −0.050), but only girls presented higher scores in the ‘Fish-based’ dietary pattern (β = 0.137; 95%CI: 0.006; 0.267). The age of introduction of complementary feeding was not significantly associated with the dietary patterns. Parents should be supported in their infant feeding decisions, given the potential effects of breastfeeding duration and first foods at complementary feeding on shaping longer term dietary patterns of young children.

Is the association between dietary patterns and cognition mediated by children's adiposity? A longitudinal approach in Generation XXI birth cohort

There is a consistent body of evidence on the association between single nutrients and cognition, but the role of a healthful dietary pattern on cognition in children has been seldomly studied. This study aims to assess the association between dietary patterns at 4 years (y) and cognitive abilities at 10-13y and examine whether adiposity mediated these associations. This study used data from a sub-sample of the population-based birth cohort Generation XXI, with complete information on diet and cognition (n=3575). At 4y, data on dietary intake was collected by a validated food frequency questionnaire and dietary patterns were derived by latent class analysis, namely Energy-dense food (EDF) pattern, Snacking pattern and Healthier pattern (Reference). At 10-13y, the Portuguese Version of the Wechsler Intelligence Scale for Children®-Third Edition was administered by trained psychologists and age-adjusted composite scores were computed: a Full-Scale Intelligence Quotient (IQ), plus a Verbal IQ, Performance IQ and Processing Speed IQ. Age- and sex-specific body mass index (BMI) z-scores, body fat percentage from bioimpedance, and waist-to-weight ratio and waist-to-hip ratio were used as measures of adiposity. Regression coefficients and 95% confidence intervals (CI) were computed using linear regression models (adjusted for maternal age and education, pre-pregnancy BMI, smoking and alcohol intake during pregnancy, child's sex, birthweight, exclusive breastfeeding duration and having siblings at 4y). Mediation analysis was conducted using path analysis. After adjustment, children classified in the EDF or a Snacking patterns at 4y were more likely to have lower scores on total IQ (β=-0.116; 95%CI:-0.192,-0.039 and β=-0.148; 95%CI-0.252,-0.044, respectively), Verbal IQ (β=-0.104; 95%CI-0.177,-0.031 and β=-0.163; 95%CI-0.262,-0.064, respectively) and Performance IQ (β=-0.116 95%CI-0.193,-0.040 and β=-0.147; 95%CI-0.250,-0.042, respectively) at 10-13y, when compared to those classified in the Healthier pattern. None of the adiposity measures seemed to explain the associations between dietary patterns and IQ. This study supports that early unhealthy dietary patterns were associated with lower child's cognitive ability, but this effect did not seem to be mediated by adiposity.

Residential and school green and blue spaces and intelligence in children: The Generation XXI birth cohort

Green and blue spaces have numerous health benefits. It has been hypothesized that contact with these spaces can have an important role in cognitive development, because it provides children with unique stimuli that can help develop curiosity, creativity, awareness, and control. This study aimed to estimate the association between exposure to green and blue spaces and the various measures of intelligence quotient (IQ) among children from Porto Metropolitan Area (Portugal).This investigation used data from the Generation XXI birth cohort. Exposure was assessed by Geographic Information Systems using vegetation indexes and measures of accessibility to urban green spaces and blue spaces in the surroundings of the residence and school, measured at 0, 4, 7 and 10 years. The outcome was the verbal, performance, and global IQ, measured using the Wechsler Intelligence Scale for Children (WISC-III), administered at age 10. Associations were estimated using crude and adjusted multilevel models. The mediation role of air pollution and physical activity was quantified.This study included 3827 children. The adjusted models showed that having green spaces up to 800 m of the residence was positively associated with performance IQ (1.30 95%CI [0.26; 2.35]) and global IQ (1.27 [0.18; 2.36]). No clear associations were observed regarding accessibility to blue spaces. Physical activity appeared to have a minor mediation role.Children with urban green spaces around their residences had higher performance and global IQ. Local actors in the sectors of public health and urban planning should promote the creation of green spaces close to residential areas.

Household Dysfunction Is Associated With Bullying Behavior in 10-year-old Children: Do Socioeconomic Circumstances Matter?

This study measured the prevalence of bullying behavior in 10-year-old children and investigated the effect of the socioeconomic context on the impact of household dysfunction on bullying. We studied 5,338 members of the Portuguese Generation XXI birth cohort. Information on involvement in bullying, socioeconomic characteristics, and household dysfunction was collected by trained interviewers using structured questionnaires. Being a victim of bullying was reported by 14.4% of participants, being a bully by 1.4%, and being a bully-victim by 3.9%. Being a victim or both bully-victim, simultaneously, was more frequent among children from medium-high income families. Also, children from low-income families who reported household substance abuse, witnessed parents’ intimate partner violence, and were victims of physical violence, were more frequently victims of bullying; and those who experienced family violence were more frequently involved as bully-victims. Among children from medium-high income families, all these household adversity experiences significantly increased the odds of being victim, bully, or bully-victim. Thus, although children from medium-high income families are less likely to experience adversity at home, when it happens, there is a greater effect on their behavior, suggesting that better socioeconomic circumstances do not seem to act as a protective factor.

Longitudinal bidirectional relationship between children's appetite and diet quality: A prospective cohort study

This study explored the relationship between eating behaviours and diet quality, from 7 to 10y. The sample included 3879 children evaluated, from the Portuguese birth cohort Generation XXI, with complete information on Food Frequency Questionnaire (FFQ) and the Children Eating Behaviour Questionnaire (CEBQ). A healthy eating index (HEI) (range: 9–31) was developed to evaluate the child's diet quality. The eight CEBQ's eating behaviours were included in the analysis. Generalised linear models were used to estimate the associations. Adjusted structural equation modelling was performed to study the direction of the associations. Eating behaviours measured at age 7y tracked to age 10y. A bidirectional inverse association between the food fussiness trait and diet quality was found, with a similar magnitude (p < 0.001), thus a higher score on food fussiness predicted a lower quality of the diet. A higher HEI score at 7y was associated with lower satiety responsiveness at 10y (βstandardized = −0.039), and a higher HEI score at age 10y was associated with higher enjoyment of food at 7y (βstandardized = 0.046). Eating behaviours were linked to diet quality in children with high enjoyment of food and low food fussiness at age 7y linked to a high-quality diet at 10y. In addition, children with high-quality diets at 7y were more likely to have lower food fussiness and satiety responsiveness at 10y. Given the stability of eating behaviours and the bidirectional nature of effects between eating behaviours and dietary quality in the long term, tailored interventions may be needed to encourage the acquisition of healthy eating behaviours and habits in early life.

Genetic and environmental contributions to variations on appetitive traits at 10 years of age: a twin study within the Generation XXI birth cohort

PurposeGiven the variability in adiposity despite ubiquitous exposure to obesogenic food environments, it has been suggested that individuals respond in divergent ways to the environment they live in. The food environment becomes more ‘permissive’ as children age; therefore, genetic predisposition for a more avid appetite can be better expressed, influencing dietary quality, energy intake and weight gain. Our aim was to explore the genetic and environmental contribution of variations on appetitive traits in a sample of 10-year-old Portuguese children.MethodsParticipants were twins enrolled in the Generation XXI birth cohort (n = 86 pairs). Parents reported twin’s zygosity and child appetitive traits at 10 years of age through the Children’s Eating Behavior Questionnaire. Intra-class correlations (ICCs) for all appetitive traits were calculated for monozygotic and dizygotic twins separately to examine patterns of resemblance, and structural equation modeling was conducted aiming to estimate the genetic (A), shared (C) and non-shared (E) environmental variances.ResultsModerate to strong heritability were found for child appetitive traits, with higher ICCs among monozygotic twin pairs. For all appetitive traits, with the exception of emotional undereating, genetic and non-shared environmental effects contributed to appetite variability. For emotional undereating, environmental effects seem to be more important than genetic effects (C: 0.81; 95% CI 0.71; 0.88 and E: 0.19; 95% CI 0.12; 0.29).ConclusionThere was a significant genetic contribution, followed by non-shared environmental contribution, towards variation in appetitive traits in school-age children. Variation in emotional undereating was primarily explained by shared and non-shared environmental factors.Level of evidenceEvidence obtained from well-designed cohort or case–control analytic studies.

Appetitive behaviors and body composition in school-age years: Bi-directional analyses in a population-based birth cohort

Cross-sectional studies have consistently associated appetitive behaviors with child body mass index. However, few prospective studies have investigated the association between appetite and other measures of body composition and its directionality. We aimed to investigate the bi-directional relationship between appetitive behaviors and body composition in school-aged children. Data from 3668 children of the Generation XXI birth cohort were analyzed. Appetitive behaviors were assessed at 7 and 10 years through the Children's Eating Behavior Questionnaire. Higher fat mass and fat-free mass were measured through tetrapolar bioelectric impedance and waist-to-weight and waist-to-height ratios were calculated. Fat and fat-free mass indexes, waist-to-weight and waist-to-height age- and sex-specific z-scores were then calculated. Cross-lagged analyses were performed (body composition at 7 to appetitive behaviors at 10 and the reverse) to measure the magnitude and direction of associations. Fat mass and waist-to-height ratio at 7y predicted greater food approach behaviors at 10y (Enjoyment of Food, Food Responsiveness, Desire to Drink and Emotional Overeating), but not waist-to-weight, which seems to be consequence of child's avid appetite (e.g. Enjoyment of Food at 7y: βstandardized = 0.085, 95%CI = 0.041; 0.128, p < 0.001). Child scores on food avoidant behaviors, such as Satiety Responsiveness (βstandardized = -0.073, 95%CI = −0.110;-0.034, p < 0.001) and Slowness in Eating (βstandardized = −0.080, 95% CI = −0.120;-0.041, p < 0.001) at 7y predicted lower fat-free mass at 10. Appetitive behaviors may not solely predict weight status, but the path of association between body composition and later appetitive behavior may also be true, especially for food approaching behaviors and adipose tissue. Interventions aiming to prevent excess weight should focus on appetitive behaviors. Moreover, in children with higher adiposity, other pathways also seem to regulate appetite and need to be considered in interventions.

Association of dehydroepiandrosterone sulfate, birth size, adiposity and cardiometabolic risk factors in 7-year-old children.

Low birth size (BS) and obesity have been associated with higher dehydroepiandrosterone sulfate (DHEAS) levels in childhood, insulin acting as a mediator, despite contradictory findings. To further explore these issues, we studied the associations between DHEAS, BS, adiposity, maternal characteristics, and cardiometabolic risk indicators, in participants of Generation XXI, a population-based birth cohort. A sample of 700 children (mean age 7.1 yr) was randomly selected. Data on maternal characteristics, BS, body mass index (BMI), waist-to-height ratio, body fat (dual-energy X-ray absorptiometry), insulin, lipid profile, and high-sensitivity C-reactive protein were analyzed in relation to DHEAS. DHEAS was negatively associated with BS and positively associated with all adiposity indicators, with no sex differences. DHEAS was positively associated with insulinemia independently of the child's BS or BMI. No significant association was found between DHEAS, maternal characteristics, lipid profile, or high-sensitivity C-reactive protein. Including insulin in the model did not affect the association between BS and DHEAS but reduced the magnitude of the BMI effect by 24% for boys and 30% for girls. Higher DHEAS levels at 7 years old were associated with lower BS and higher adiposity. DHEAS levels were positively associated with insulinemia independently of BS or BMI. Low birth weight and obesity have been associated with higher dehydroepiandrosterone sulfate (DHEAS) levels in prepuberty. Insulin has been suggested as a mediator, despite previous studies failing to show an association between DHEAS and insulin levels. In a randomly selected population of 700 7-year-old children from the Generation XXI birth cohort, higher DHEAS levels were associated with a lower birth size and higher adiposity, with no sex differences. DHEAS was positively related to insulinemia independently of the child's birth size or body mass index. No association was found between DHEAS and other cardiometabolic risk factors.

Food parenting practices and eating behaviors in childhood: a cross-lagged approach within the Generation XXI cohort

Food parenting practices have been associated with children's eating behaviors, but analyses exploring the bidirectional effects are limited. We aimed to examine the bidirectional relations between food parenting practices and the eating behavior of children from 4 to 7 y old. Participants are from the Generation XXI birth cohort (Portugal) assessed at both 4 and 7 y of age (n=3698 singletons). A validated version of the Child Feeding Questionnaire and the overt/covert control scale were used. Three patterns of food parenting practices (Perceived Monitoring, Restriction, and Pressure to eat) were studied. Perception of children's eating behaviors (eating large amounts of food, eating very slowly, and food refusal) was reported by parents (measured using dichotomous questions). Cross-lagged analyses were performed to evaluate the direction of the associations (parenting practices at 4 y to behaviors at 7 y and the reverse). Eating large amounts of food was unidirectionally associated with higher Restriction 3 y later (βstandardized=0.047; 95% CI: 0.019, 0.075). Apart from Restriction, all associations had a bidirectional effect of similar magnitude. Eating large amounts of food and food refusal at age 4 influenced food parenting, such as Perceived Monitoring and Pressure to eat at age 7, but these practices were prospectively linked to these eating behaviors too (e.g., βstandardized=0.033; 95% CI: 0.022, 0.064 for food refusal at age 4 and Pressure to eat at age 7, and βstandardized=0.060; 95% CI: 0.034, 0.086, in the reverse direction). Parenting practices and children's eating behaviors showed significant moderate tracking (standardized path coefficients from 0.24 to 0.49). Eating large amounts of food, eating slowly, and food refusal can influence parents to adopt certain food parenting practices, but these practices also influence children's behaviors after a few years. This reciprocal relation should be considered in future research. Parents should be advised to use food parenting practices associated with healthier eating behaviors.

Maternal perception, concern and dissatisfaction with child weight and their association with feeding practices in the Generation XXI birth cohort

What a mother thinks about her child's weight status might influence what and how she feeds her child. We examined the association between maternal perception, concern and dissatisfaction with child weight alongside feeding practices. Participants were from the Generation XXI birth cohort (n = 3233). A validated version of the Child Feeding Questionnaire and the Overt/Covert Control scale were used. Associations were evaluated by linear regression models (β coefficients and 95 % confidence intervals (95 % CI) with Bonferroni correction). Perceived underweight was associated with practices promoting food intake, such as higher pressure to eat at ages 4 and 7 years (β = 0·229; 95 % CI: 0·059, 0·398 and β = 0·190; 95 % CI:0·005, 0·376, respectively) and lower restriction at age 4 (β = -0·175; 95 % CI: -0·0310, -0·039). At age 7, perceived overweight was associated with higher covert control (β = 0·203; 95 % CI: 0·029, 0·376). Mothers who were concerned about child weight reported higher restriction (β = 0·226; 95 % CI: 0·142, 0·310 at 4 years and β = 0·261; 95 % CI: 0·169, 0·353 at 7 years) and covert control (β = 0·183; 95 % CI: 0·083, 0·282 at 4 years and β = 0·171; 95 % CI: 0·073, 0·269 at 7 years). Maternal desire for a heavier child was associated with higher pressure to eat at both ages (β = 0·285; 95 % CI: 0·163, 0·406 and β = 0·393; 95 % CI: 0·266, 0·520), while the desire for a thinner child was related to higher covert control at 7 years of age (β = 0·158; 95 % CI: 0·001, 0·316). Maternal perceptions and concern for child weight status are associated with feeding practices independently of actual weight status.

Use of a hybrid method to derive dietary patterns in 7 years olds with explanatory ability of body mass index at age 10.

The usual definition of dietary patterns only accounts for the explanation of dietary choices and not a specific health outcome. This could partially explain the lack of consistent associations between diet and related diseases. This study aims to identify dietary patterns in 7 years olds explaining body mass index (BMI) at age 10 and to assess their association with early-life factors (sociodemographic, birth, and infancy characteristics). Children from the birth cohort Generation XXI at ages 7 and 10 were included (n = 4698). Diet was assessed by a validated food-frequency questionnaire. Measured BMI z-scores (zBMI) were calculated. Principal component analysis (PCA) and partial least squares (PLS) were run to derive dietary patterns. The component scores of PCA was able to explain 13.0% of food groups and only 0.2% of zBMI, while the PLS scores explained the variance of both food groups (10.1%) and zBMI at age 10 (4.2%). By using PLS, two dietary patterns were derived, but only one, higher in processed meats and energy-dense foods and lower in vegetable soup consumption, was significantly associated with an increased zBMI in 10 years olds (adjusted β̂ 0.032; 95% CI:0.017; 0.047). It was more likely followed by children from younger and less educated mothers and who were born heavier. A dietary pattern higher in processed and energy-dense foods and with lower vegetable soup intake in 7 years olds significantly explained zBMI of 10 years olds, and was predicted by early-life characteristics. The other dietary patterns were not significantly associated with zBMI at age 10.

Adiposity rebound and cardiometabolic health in childhood: results from the Generation XXI birth cohort.

We aimed to evaluate the association of adiposity rebound (AR) timing on cardiometabolic health in childhood. Participants were part of the Generation XXI birth cohort, enrolled in 2005/2006 in Porto. All measurements of the child's weight and height performed by health professionals as part of routine healthcare were collected. Individual body mass index (BMI) curves were fitted for 3372 children, using mixed-effects models with smooth spline functions for age and random effects. The AR was categorized into very early (<42 months), early (42-59 months), normal (60-83 months) and late (≥84 months). At age 10 years, cardiometabolic traits were assessed and age- and sex-specific z-scores were generated. Adjusted regression coefficients and 95% confidence intervals [β (95% CI)] were computed. The mean age at AR was 61.9 months (standard deviations 15.7). Compared with children with normal AR, children with very early or early AR had higher z-scores for BMI [β = 0.40 (95% CI: 0.28; 0.53); β = 0.21 (95% CI: 0.12; 0.30)], waist circumference [β = 0.33 (95% CI: 0.23; 0.43); β = 0.18 (95% CI: 0.10; 0.25)], waist-height ratio [β = 0.34 (95% CI: 0.24; 0.44); β = 0.14 (95% CI: 0.07; 0.22)], fat mass index [β = 0.24 (95% CI: 0.15; 0.33); β = 0.14 (95% CI: 0.08; 0.21)], fat-free mass index [β = 0.25 (95% CI: 0.14; 0.35); β = 0.11 (95% CI: 0.03; 0.19)], systolic blood pressure [β = 0.10 (95% CI: 0.01; 0.20); β = 0.08 (95% CI: 0.01; 0.15)], insulin [β = 0.16 (95% CI: 0.04; 0.29); β = 0.10 (95% CI: 0.01; 0.19)], HOMA-IR [β = 0.17 (95% CI: 0.04; 0.29); β = 0.10 (95% CI: 0.03; 0.19)] and C-reactive protein [β = 0.14 (95% CI: 0.02; 0.26); β = 0.10 (95% CI: 0.01; 0.19)]. Children with very early AR also had worse levels of diastolic blood pressure [β = 0.09 (95% CI: 0.02; 0.16)], triglycerides [β = 0.21 (95% CI: 0.08; 0.34)] and high-density lipoprotein cholesterol [β=-0.18 (95% CI: -0.31; -0.04)]. When analysed continuously, each additional month of age at the AR was associated with healthier cardiometabolic traits. The earlier the AR, the worse the cardiometabolic health in late childhood, which was consistently shown across a wide range of outcomes and in the categorical and continuous approach.

Use of antibiotics during pregnancy is associated with infection in children at four years of age in Portugal.

To assess the association between taking antibiotics in pregnancy and the occurrence of infections in children at four years of age. We studied children who participated in the follow-up of the birth cohort Generation XXI, Porto-Portugal, at the age of four years. We evaluated the associations between the use of antibiotics by the mother at any time in pregnancy with the occurrence of infections. Data were analysed using logistic regression, controlling for potential confounding variables. We studied 7459 children (50.7% boys). The use of antibiotics at any stage of pregnancy, and not only in the third trimester, was associated with the occurrence of tonsillitis at four years, even after controlling for potential confounders (OR 1.19, 95% CI 1.03-1.38). Other infections did not show association. Maternal use of antibiotics during pregnancy was associated with an increased risk of tonsillitis reported at four years of age. Antibiotics could favour the potential transmission of an unfavourable microbiome from mother to child.

Serum Levels of Vitamin D and Dental Caries in 7-Year-Old Children in Porto Metropolitan Area.

Vitamin D deficiency has been associated with significant changes in dental structures. In children, it can induce enamel and dentin defects, which have been identified as risk factors for caries. This study aimed to assess the association between low serum 25-hydroxyvitamin D (25(OH) D) levels (<30 ng/mL) and the prevalence of caries in the permanent teeth and mixed dentition of 7-year-old children. A sample of 335 children from the population-based birth cohort Generation XXI (Porto, Portugal) was included. Data on children’s demographic and social conditions, health status, dental health behaviours, dental examination including erupted permanent first molars, and blood samples available for vitamin D analysis were collected. Dental outcomes included the presence of caries, including non-cavitated lesions (d1–6mft/D1–6MFT > 0), and advanced caries (d3–6mft/D3–6MF > 0). Serum 25(OH) D was measured using a competitive electrochemiluminescence immunoassay protein-binding assay. Bivariate analysis and multivariate logistic regression were used. Advanced caries in permanent teeth was significantly associated with children’s vitamin D levels <30 ng/mL, gastrointestinal disorders, higher daily intake of cariogenic food, and having had a dental appointment at ≤7 years old. Optimal childhood levels of vitamin D may be considered an additional preventive measure for dental caries in the permanent dentition.

Mother-reported pain experience between ages 7 and 10: A prospective study in a population-based birth cohort.

Trajectory studies suggest considerable stability of persistent or recurrent pain in adolescence. This points to the first decade of life as an important aetiologic window for shaping future pain, where the potential for prevention may be optimised. We aimed to quantify changes in mother-reported pain experience in children between ages 7 and 10 and describe clusters of different pain experiences defined by complementary pain features. We conducted a prospective study using data from 4036 Generation XXI birth cohort participants recruited in 2005-06. Pain history was reported by mothers at ages 7 and 10 using the Luebeck pain screening questionnaire. We tracked changes in six pain features over time using relative risks (RRs) and their 95% confidence intervals (95% CIs). Clusters were obtained using the k-medoids algorithm. The risk of severe pain at age 10 increased with increasing severity at age 7, with RRs ranging from 2.18 (95% CI 1.90, 2.50) for multisite to 4.43 (95% CI 3.19, 6.15) for high frequency pain at age 7. A majority of children (59.4%) had transient or no pain but two clusters included children with stable recurrent pain (n=404, 10.2% of the sample). One of those (n=177) was characterised by higher probabilities of multisite pain (74.6% and 66.7% at ages 7 and 10, respectively), with psychosocial triggers/contexts (59.3% and 61.0%) and daily-living restrictions (72.2% and 84.6%). Most children in that cluster (58.3%) also self-reported recent pain at age 10 and had more frequent family history of chronic pain (60.5%). All pain features assessed tracked with a positive gradient between ages 7 and 10, arguing for the significance of the first decade of life in the escalation of the pain experience. Multisite pain and psychosocial attributions appeared to be early markers of more adverse pain experiences.

The effect of sugar-sweetened beverages at 4 years of age on appetitive behaviours of 7-year-olds from the Generation XXI birth cohort.

The consumption of energy-dense sugar-sweetened beverages (SSB) and its low satiating effects may influence the development of child eating behaviours. We aimed to investigate the association of SSB consumption at 4 years on appetitive behaviours at age 7 years. Children from the Generation XXI birth cohort were included (n 3880). SSB consumption was evaluated through a FFQ and appetitive behaviours were evaluated through the Children's Eating Behaviour Questionnaire, which includes eight subscales. Two composite factors, derived by principal component analysis (Appetite Restraint - related to Food Fussiness, Enjoyment of Food, Slowness in Eating and Satiety Responsiveness - and Appetite Disinhibition - related to Food Responsiveness, Emotional Under- and Overeating and Desire to Drink), were also investigated. The dose-response relationship between SSB consumption and appetitive behaviours was examined using multivariable linear regression (continuous eating behaviour scores) and multinomial logistic regression (tertile categories of eating behaviour scores). Child SSB consumption at 4 years was associated with higher Appetite Disinhibition and Desire to Drink and lower Food Fussiness and Slowness in Eating at 7 years. Consuming SSB ≥1 times/d (compared with a lower intake) was associated with 29 % increase in the odds of Desire to Drink (3rd v. 1st tertile). Pre-schoolers' SSB consumption was associated with higher food approach and less food avoidant behaviours later in childhood. Family characteristics, particularly maternal SSB consumption, explained part of these associations. It is essential to promote the intake of water, instead of sugary drinks, and make parents and caregivers aware of the importance of this exposure, since they have a pivotal role in shaping children's eating behaviours.

Ultra-processed food consumption, appetitive traits and BMI in children: a prospective study.

This study aimed to investigate the association of ultra-processed food consumption at 4 and 7 years of age with appetitive traits at 7 years and BMI at 10 years of age. Participants were 1175 children of the population-based birth cohort Generation XXI, who provided food diaries and complete data on socio-demographic variables, anthropometric measures and the Portuguese Children's Eating Behaviour Questionnaire (P-CEBQ). Foods were grouped according to NOVA classification into: 'unprocessed, minimally or moderately processed, and culinary preparations'; 'processed' and 'ultra-processed'. To assess tracking of groups' consumption, Pearson's correlation coefficient (r) and the intraclass correlation coefficient (ICC) were calculated. Generalised linear models were fitted to test main associations, mediators and interactions among the variables. Ultra-processed consumption exhibited a fair level of stability between ages 4 and 7 years (r 0·34; ICC = 0·32; 95 % CI 0·25, 0·39), corresponding, respectively, to 27·3 % (1881·9 (SD 908·8) kJ/d) and 29·3 % (2204·5 (SD 961·1) kJ/d) of total energy intake. After adjusting for maternal and child characteristics, higher ultra-processed consumption at 4 years was associated directly with 'Food Responsiveness' (β = 0·019; 95 % CI 0·007, 0·037) and indirectly through energy intake with avoidant traits: 'Food Fussiness' (β = -0·007; 95 % CI 0·002, 0·012) and 'Satiety Responsiveness' (β = -0·007; 95 % CI 0·003, 0·012). Ultra-processed consumption at 4 years old was associated with BMI at 10 years old, but appetitive behaviours were not powerful mediators of this association. The results suggest a path by which ultra-processed products may impact on later appetitive traits and higher BMI in children.