Association of Physical Activity and Cardiometabolic Risk in Children 3-12 Years.

BACKGROUND: This study aimed to examine the association between physical activity (PA) and a total cardio metabolic risk (CMR) score in children aged 3-12 years. Secondary objectives were to examine the association between PA and individual CMR factors. METHODS: A longitudinal study with repeated measures was conducted with participants from a large primary care practice-based research network in Toronto, Canada. Mixed effects models were used to examine the relationship between parent-reported physical activity and outcome variables (total CMR score, triglycerides, glucose, high-density lipoprotein cholesterol, systolic blood pressure, waist circumference, weight-to-height ratio, and non-high-density lipoprotein cholesterol). RESULTS: Data from 1885 children (6.06 y, 54.4% male) with multiple visits (n = 2670) were included in the analyses. For every unit increase of 60 minutes of PA, there was no evidence of an association with total CMR score (adjusted: -0.02 [-0.014 to 0.004], P = .11]. For the individual CMR components, there was evidence of a weak association between PA and systolic blood pressure (-0.01 [-0.03 to -0.01], P < .001) and waist-to-height ratio (-0.81 [-1.62 to -0.003], P < .001). CONCLUSION: Parent-reported PA among children aged 3-12 years was not statistically associated with total CMR, but was weakly associated with systolic blood pressure and waist-to-height ratio.

Sugar-containing beverage consumption and cardiometabolic risk in preschool children.

OBJECTIVE: Sugar-containing beverages (SCBs) including 100% fruit juice, fruit drinks and soda substantially contribute to total caloric intake in young children. The objective of this study was to examine whether consumption of SCB is associated with cardiometabolic risk (CMR) in preschool children, along with whether 100% fruit juice and sugar sweetened beverage (SSB) is associated with CMR. STUDY DESIGN: We used a repeated measures study design examining SCB consumption and CMR outcomes measured concurrently in children 3-6 years of age participating in TARGet Kids!, a primary-care, practice-based research network in Canada (2008-2017). To account for within-person variability, multivariable linear regression models using generalized estimating equation was used to examine the association between SCB consumption and CMR score and the individual CMR score components including systolic blood pressure, waist circumference, high-density lipoprotein cholesterol (HDL-c), triglycerides, and glucose. RESULTS: After adjusting for sociodemographic, familial and child-related covariates, higher SCB consumption was associated with elevated CMR score [0.05 (95% CI -0.0001 to 0.09), p = 0.05], including lower HDL-c [-0.02 mmol/L (95% CI -0.03 to -0.01), p = 0.01] and higher triglycerides [0.02 mmol/L (95% CI 0.004 to 0.04), p = 0.02]. When examined separately, higher 100% fruit juice [-0.02 mmol/L (95% CI -0.03 to -0.003), p = 0.02] and SSB[-0.03 mmol/L (95% CI -0.06 to -0.001), p = 0.04] consumption were each associated with lower HDL-c. CONCLUSION: Higher SCB consumption was associated with small elevations of CMR in preschool children. Our findings support recommendations to limit overall intake of SCBs in early childhood, in effort to reduce the potential long-term burden of CMR.

A Positive Association Between Dietary Intake of Higher Cow's Milk-Fat Percentage and Non-High-Density Lipoprotein Cholesterol in Young Children.

OBJECTIVES: To determine the association between cow's milk-fat and non-high-density lipoprotein (non-HDL) cholesterol, a marker of cardiovascular disease (CVD) risk in young children, and whether this association is mediated by the typical volume of cow's milk consumed. STUDY DESIGN: A longitudinal study in 2- to 8-year-old children (n = 2890) was conducted through The Applied Research Group for Kids (TARGet Kids!), a practice-based research network in Toronto, Canada. Generalized estimating equations were used to examine the relationship between parent-reported cow's milk-fat percentage intake and serum non-HDL cholesterol concentrations as well as having high non-HDL cholesterol (≥3.75 mmol/L [145 mg/dL]), adjusting for covariates including age, sex, body mass index z score, breastfeeding duration, mother's ethnicity, and parental history of CVD. Bootstrap resampling (10 000 repetitions) was used to assess whether typical volume consumed mediated the association between cow's milk-fat percentage and non-HDL cholesterol. RESULTS: In total, 156 (5.4%) had high non-HDL cholesterol. Each percent increase in cow's milk-fat was associated with a 0.035 mmol/L (1.35 mg/dL) (P < .001) and 0.024 mmol/L (0.92 mg/dL) (P = .01) increase in non-HDL cholesterol, unadjusted and adjusted for covariates respectively. Cow's milk-fat percentage was not associated with greater odds of having high non-HDL cholesterol. Volume of cow's milk partially mediated the association between cow's milk-fat percentage and non-HDL cholesterol, accounting for 28% of the relationship (P < .001). CONCLUSIONS: Consumption of higher-fat cow's milk was associated with a small increase in non-HDL cholesterol but not greater odds of having high non-HDL cholesterol. Further research is needed to assess this relationship with other CVD risk factors in young children. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01869530.

Association of accelerated body mass index gain with repeated measures of blood pressure in early childhood.

BACKGROUND/OBJECTIVES: We examined the association for rates of age- and sex-standardized body mass index (zBMI) gain between 0-3, 3-18, and 18-36 months with BP in children at 36-72 months of age. METHODS: We collected repeated measures of zBMI and BP in 2502 children. zBMI was calculated using the World Health Organization standards. Each child's zBMI at birth and rates of zBMI gain in each period from birth to 36 months were estimated using linear spline multilevel models. Generalized estimating equations were used to determine whether zBMI at birth and zBMI gain between 0-3, 3-18, and 18-36 months were each associated with repeated measures of BP at 36-72 months of age. We sequentially conditioned on zBMI at birth and zBMI gain in each period prior to each period tested, as covariates, and adjusted for important socio-demographic, familial, and study design covariates. We examined whether these associations were modified by birthweight or maternal obesity, by including interaction terms. RESULTS: After adjusting for all covariates and conditioning on prior zBMI gains, a 1 standard deviation unit faster rate of zBMI gain during 0-3 months, (ß = 0.59 mmHg; 95% CI 0.31, 0.86) and 3-18 months (ß = 0.74 mmHg; 95% CI 0.46, 1.03) were each associated with higher systolic BP at 36-72 months. No significant associations were observed, however, for zBMI at birth or zBMI gain in the 18-36 month growth period. zBMI gains from 0-3 and 3-18 months were also associated with diastolic BP. Birthweight significantly modified the relationship during the 3-18 month period (p = 0.02), with the low birthweight group exhibiting the strongest association for faster rate of zBMI gain with higher systolic BP (ß = 1.31 mmHg; 95% CI 0.14, 2.48). CONCLUSIONS: Given that long-term exposure to small elevations in BP are associated with subclinical cardiovascular disease, promoting interventions targeting healthy growth in infancy may be important.

Total Breastfeeding Duration and Household Food Insecurity in Healthy Urban Children.

OBJECTIVE: Health care policy positions breastfeeding as an important part of the solution to household food insecurity; however, there are critical gaps in our knowledge of the relationship between breastfeeding duration (exposure variable) and household food insecurity (outcome variable). Our objective was to examine this relationship. METHODS: A cross-sectional study was conducted from 2008 to 2016 of healthy urban children (N = 3838) who were 0 to 3 years old and recruited from The Applied Research Group for Kids (TARGet Kids!), a practice-based research network in Toronto, Canada. Total breastfeeding duration was collected from parent-reported questionnaires. Household food insecurity was measured using 1-item and 2-item food insecurity screens. Multivariable regression analysis was performed adjusting for prespecified covariates. RESULTS: The median total breastfeeding duration was 10.5 months (interquartile range, 6.0-14.0), and 14.7% of households were food insecure. After adjusting for child characteristics (age, sex), maternal characteristics (age, ethnicity, education, employment), and family characteristics (number of children, single parent family, neighborhood equity score), there was no significant association between total breastfeeding duration and household food insecurity (odds ratio, 0.99; 95% confidence interval, 0.98-1.01). Although low-income families had an increased odds of being household food insecure (P ≤ .001), we found no significant association between total breastfeeding duration and household food insecurity at varying income levels. CONCLUSIONS: We found no association between breastfeeding duration and household food insecurity, regardless of family income. Although breastfeeding is associated with improved child health outcomes and considered to be part of the solution to household food insecurity, interventions focused on social determinants may provide more promising targets for the prevention of household food insecurity.

Mobile Media Device Use is Associated with Expressive Language Delay in 18-Month-Old Children.

OBJECTIVE: The objective was to examine the association between mobile media device use and communication delays in 18-month-old children. METHODS: A cross-sectional study was conducted from September 2011 and December 2015 within the TARGet Kids! primary care research network. Children were included if parents reported their child's mobile media device use and completed a validated questionnaire for communication delay at the 18-month well child visit. Mobile media device use was measured using a parent-reported survey instrument. Daily mobile media device use was calculated as a weighted average of typical weekday and weekend day mobile media device use. Two communication outcomes were investigated: (1) expressive speech delay and (2) other communication delays, as measured by the Infant Toddler Checklist. RESULTS: The study sample included 893 children (mean age 18.7 months, 54.1% male). Most parents reported 0 minutes per day of mobile media device use in their children (n = 693, 77.6%). Among children whose parents reported any mobile media device use (n = 200, 22.4%), the median daily mobile media device use was 15.7 minutes (range 1.4-300). The prevalence of parent-reported expressive speech delay was 6.6%, and the prevalence of other parent-reported communication delays was 8.8%. For children who used a mobile media device, each additional 30-minute increase in daily mobile media device use was associated with increased odds of parent-reported expressive speech delay (ORa = 2.33, 95% confidence interval, 1.25-4.82). No relationship was observed between mobile media device use and other parent-reported communication delays. CONCLUSION: Our study demonstrated a significant association between mobile media device use and parent-reported expressive speech delay in 18-month-old children.

Effect of High-Dose Vitamin D Supplementation on Upper Respiratory Tract Infection Symptom Severity in Healthy Children.

BACKGROUND: Observational studies support the role of vitamin D in reducing viral upper respiratory tract infection (URTI) symptom severity in adults and children. This study assessed whether wintertime high-dose vitamin D supplementation (2000 IU/day) reduces URTI symptom severity compared with standard-dose (400 IU/day) supplementation in preschool children. Secondary objectives were to assess effects of high-dose supplementation on outpatient physician visits, emergency department (ED) visits and antibiotic prescriptions for URTI. METHODS: This was a secondary analysis of a multisite randomized clinical trial involving 703 healthy 1- to 5-year-old children in Toronto, Canada. High-dose or standard-dose oral vitamin D was randomly assigned for 1 winter season. For each URTI, parents completed symptom checklists based on the Canadian Acute Respiratory and Flu Scale. Symptom severity, frequency of outpatient visits, ED visits and antibiotic prescriptions for URTI between groups were analyzed using negative binomial regression. RESULTS: URTI symptom severity was not reduced in the high-dose vs. standard-dose group [incidence rate ratio (IRR) = 0.97; 95% confidence interval (CI): 0.76-1.23]. High-dose vitamin D did not decrease frequency of outpatient visits (IRR = 1.16; 95% CI: 0.84-1.60), ED visits (IRR = 1.17; 95% CI: 0.57-2.40) or antibiotic prescriptions (IRR=1.02; 95% CI: 0.61-1.72). Serum 25-hydroxyvitamin D was higher in the high-dose group (48.7 ng/mL; 95% CI: 46.9-50.5) than the standard-dose group (36.8 ng/mL; 95% CI: 35.4-38.2; P < 0.001). CONCLUSIONS: High-dose vitamin D supplementation did not reduce URTI symptom severity, outpatient visits, ED visits or antibiotic prescriptions relative to standard-dose. These results do not support vitamin D supplementation above the standard recommended dose for reducing URTI symptoms in children.

Breastfeeding to 12 mo and beyond: nutrition outcomes at 3 to 5 y of age.

Background: Little is known about nutrition outcomes in preschoolers associated with breastfeeding duration beyond 12 mo of age. Objective: The aim was to examine the association between total breastfeeding duration and nutrition outcomes at 3 to 5 y of age. Design: A cross-sectional study in healthy children, ages 3-5 y, recruited from 9 primary care practices in Toronto was conducted through the TARGet Kids! (The Applied Research Group for Kids) research network. Parents completed standardized surveys, including the Nutrition Screening for Every Preschooler (NutriSTEP) used to assess nutrition risk. Results: A total of 2987 children were included. Ninety-two percent of children were breastfed, and the mean ± SD breastfeeding duration was 11.4 ± 8.4 mo. The prevalence of nutrition risk (score >20) was 17.0%. We examined breastfeeding duration as a continuous variable. With the use of restricted cubic spline modeling, we confirmed a nonlinear relation between breastfeeding duration and NutriSTEP score, dietary intake and eating behavior subscores, and sugar-sweetened beverage and sweet-savory snack consumption. Segmented linear regression was used to examine this nonlinear relation in a piecewise approach. We found a decreasing trend in NutriSTEP score for children who were breastfed for 0-6 mo (ß = -0.14; 95% CI: -0.29, 0.004), a significant decrease in NutriSTEP score for children breastfed for 6-12 mo (ß = -0.20; 95% CI: -0.33, -0.07), and no significant change after 12 mo (ß = 0.09; 95% CI: -0.07, 0.24) and beyond. The mean ± SD NutriSTEP scores were 17.1 ± 7.4 for no breastfeeding, 15.9 ± 6.5 for breastfeeding >0-6 mo, 13.9 ± 6.2 for >6-12 mo, 13.7 ± 6.3 for >12-18 mo, 14.6 ± 6.7 for >18-24 mo, and 14.3 ± 6.8 for >24-36 mo. Conclusions: Breastfeeding for ≤12 mo was associated with decreased nutrition risk and healthier eating behaviors and dietary intake at 3-5 y of age. We found insufficient evidence of additional benefit for breastfeeding beyond 12 mo of age. The TARGet Kids! practice-based research network is registered at www.clinicaltrials.gov as NCT01869530.

Persistent High Non-High-Density Lipoprotein Cholesterol in Early Childhood: A Latent Class Growth Model Analysis.

OBJECTIVES: To examine patterns of non-high-density lipoprotein (HDL) cholesterol in early childhood and identify factors associated with persistent high non-HDL cholesterol in healthy urban children. STUDY DESIGN: We identified all children enrolled in a primary care practice-based research network called TARGet Kids! (The Applied Research Group for Kids) with ≥3 laboratory measurements of non-HDL cholesterol. Latent class growth model analysis was performed to identify distinct trajectory groups for non-HDL cholesterol. Trajectory groups were then categorized into "normal" vs "persistent-high" non-HDL cholesterol based on guideline cut-off values and logistic regression was completed to examine the association between trajectory group and the presence of anthropometric and cardiometabolic risk factors. RESULTS: A total of 608 children met inclusion criteria for the trajectory analysis (median age at enrolment = 18.3, IQR = 27.9 months). Four trajectory groups were identified with 2 groups (n = 451) categorized as normal non-HDL cholesterol and 2 groups (n = 157) as persistent high non-HDL cholesterol. Family history of high cholesterol (OR 2.04, 95% CI 1.27-3.28) was associated significantly with persistent high non-HDL cholesterol, whereas East/Southeast Asian vs European ethnicity (OR 0.33, 95% CI 0.14-0.78), longer breastfeeding duration (OR 0.96, 95% CI 0.93-1.00), and greater birth weight (OR 0.69, 95% CI 0.48-1.00) were associated with lower odds of persistent high non-HDL cholesterol. CONCLUSIONS: Patterns of non-HDL cholesterol are identified during early childhood, and family history of high cholesterol was associated most strongly with persistent high non-HDL cholesterol. Future research should inform the development of a clinical prediction tool for lipids in early childhood to identify children who may benefit from interventions to promote cardiovascular health.