Bi-directional associations between physical activity and growth indicators of pre-school aged children.

Physical activity for young children provides a wealth of benefits for health and development. However, little is known about the inter-relationship of physical activity and growth indicators. The aim of this study was to test the bi-directional associations of physical activity and growth indicators in children under five years of age. This prospective study included 1,575 children with data on physical activity and growth indicators at ages 12, 24 and 48 months. Accelerometers were used to measure physical activity. Z-scores for length/height-for-age, weight-for-length/height, weight-for-age and body mass index (BMI)-for-age were calculated. Bi-directional associations between physical activity and growth indicators were evaluated using cross-lagged panels based on Generalized Estimating Equations and cross-lagged structural equation models. Physical activity was consistently associated with lower weight-related growth indicators: BMI-for-age: ß=-0.12; Weight-for-age: ß=-0.11; Weight-for-length/height: ß=-0.12. Higher BMI-for-age indicated lower physical activity (ß=-0.06). When the exposure was lagged, the association of physical activity on weight-related growth indicators remained, but weight-related growth indicators showed a negative association on physical activity. A bi-directional association between physical activity and weight-related growth indicators was observed. The magnitude of associations were stronger when physical activity was modelled as exposure. These results reinforce the importance of physical activity since early years.

Longitudinal Associations Between Device-Measured Physical Activity and Early Childhood Neurodevelopment.

BACKGROUND: The aim of this study was to investigate longitudinal associations between physical activity and early childhood neurodevelopment. METHODS: Data from 1673 children from the 2015 Pelotas (Brazil) birth cohort study were analyzed. Physical activity was measured using accelerometers on the wrist at ages 1, 2, and 4 years. Neurodevelopment was measured using the Battelle Development Inventory at age 4 years. Linear regression models were used to test trajectories and cumulative associations of physical activity with child neurodevelopment. RESULTS: Of the 3 physical activity trajectories observed, children in the medium (ß = 1.17; 95% confidence interval, 0.25 to 2.10) and high (ß = 2.22; 95% confidence interval, 0.61 to 3.82) trajectories showed higher neurodevelopment scores than children in the lower activity trajectory. Cumulative analyses showed that children in the highest tertile of physical activity in all follow-ups presented a mean neurodevelopment score 4.57 (95% confidence interval, 2.63 to 6.51) higher than children in the lowest tertile in all follow-ups. All analyses showed a dose-response characteristic of association, with higher physical activity indicating higher neurodevelopment scores. CONCLUSIONS: Physical activity may be an important predictor of neurodevelopment through early childhood.

Implementation of a Physician Incentive Program for 18-Month Developmental Screening in Ontario, Canada.

OBJECTIVES: To evaluate factors associated with uptake of a financial incentive for developmental screening at an enhanced 18-month well-child visit (EWCV) in Ontario, Canada. STUDY DESIGN: Population-based cohort study using linked administrative data of children (17-24 months of age) eligible for EWCV between 2009 and 2017. Logistic regression modeled associations of EWCV receipt by provider and patient characteristics. RESULTS: Of 910 976 eligible children, 54.2% received EWCV (annually, 39.2%-61.2%). The odds of assessment were lower for socially vulnerable children, namely, those from the lowest vs highest neighborhood income quintile (aOR, 0.84; 95% CI, 0.83-0.85), those born to refugee vs nonimmigrant mothers (aOR, 0.90; 95% CI, 0.88-0.93), and to teenaged mothers (aOR, 0.70; 95% CI, 0.69-0.71)). Children were more likely to have had developmental screening if cared for by a pediatrician vs family physician (aOR, 1.28; 95% CI, 1.13-1.44), recently trained physician (aOR, 1.38; 95% CI, 1.29-1.48 for ≤5 years in practice vs ≥21 years) and less likely if the physician was male (aOR, 0.64; 95% CI, 0.61-0.66). For physicians eligible for a pay-for-performance immunization bonus, there was a positive association with screening. CONCLUSIONS: In the context of a universal healthcare system and a specific financial incentive, uptake of the developmental assessment increased over time but remains moderate. The implementation of similar interventions or incentives needs to account for physician factors and focus on socially vulnerable children to be effective.

Baroreflex sensitivity is associated with sleep-related breathing problems in adolescents.

OBJECTIVES: To examine the relationship between sleep-related breathing problems (SRBPs) and baroreflex sensitivity (BRS) among adolescents and assesses whether body mass influences this relationship. STUDY DESIGN: SRBPs were assessed in 106 adolescents aged 11-14 years using the Pediatric Sleep Questionnaire. Body mass index (BMI) was calculated, and 5 minutes of continuous beat-to-beat blood pressure (Finapres) and R-R interval were recorded (standard electrocardiogram) after 15 minutes of supine rest. Spectral indices were computed using fast Fourier transform, and transfer function analysis was used to compute BRS. RESULTS: Regression analyses indicate an interaction between BMI and SRBPs (b=-.151, P=.015) on BRS. Graphing the interaction showed that those with higher SRBP scores had lower BRS but that this effect was stronger for those with higher BMI. CONCLUSIONS: Adolescents with elevated SRBP scores had lower BRS. In addition, higher BMI amplified the risk of higher SRBP scores on BRS.

Developmental coordination disorder, generalized self-efficacy toward physical activity, and participation in organized and free play activities.

OBJECTIVE: To test a theoretical model linking developmental coordination disorder (DCD) to reduced physical activity (PA) through the mediating influence of generalized self-efficacy regarding PA. STUDY DESIGN: This was a cross-sectional investigation of students in grades 4 through 8 from 5 elementary schools in the Niagara region of Ontario, Canada (n=590). Motor proficiency was evaluated using the short-form Bruininks-Oseretsky Test of Motor Proficiency. Generalized self-efficacy was assessed using the Children's Self-Perceptions of Adequacy in and Predilection for Physical Activity scale, and PA levels were evaluated using a 61-item Participation Questionnaire. Structural equation modeling was used to test the influence of generalized self-efficacy on the relationship between DCD and PA. RESULTS: In this sample, 7.5% (n=44) of the children met the requirements for probable DCD. The effect of DCD on PA was mediated by generalized self-efficacy. In this model, 28% of the variance in children's PA was predicted by generalized self-efficacy and DCD. CONCLUSIONS: Our results suggest that children with DCD are less likely to be physically active and that generalized self-efficacy can account for a considerable proportion of this relationship. The implications for appropriate interventions to increase PA among children with DCD are discussed.