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

Evaluation of ethnic differences in cardiometabolic risk in children

PURPOSE

In adults, cardiometabolic conditions manifest differently by ethnicity with South Asians particularly predisposed. Whether these differences arise in childhood remains narrowly explored. To address this evidence gap, we examined whether children of different ethnicities display differences in cardiometabolic risk (CMR).

METHODS

A cross-sectional analysis was conducted among 5557 children (3-11 years). Multivariable linear regression models adjusted for age, sex, z-body mass index, and demographic factors were used to estimate differences in CMR outcomes between children with parents that self-reported European ancestry (reference group) and one of 13 other ethnicities (African, Arab, East Asian, Latin American, South Asian, Southeast Asian, Mixed Ethnicities, and Other). The primary outcome was a CMR score, calculated as the sum of age- and sex-standardized waist circumference, systolic blood pressure (SBP), glucose, log-triglycerides, and inverse high-density lipoprotein cholesterol (HDL-C), divided by √5.

RESULTS

Lower mean CMR scores were observed among children with African (β = -0.62, 95% CI: -0.92; -0.32) and East Asian (β = -0.41, 95% CI: -0.68, -0.15) ancestry compared to children with European ancestry. Children with South Asian ancestry had higher SBP (β = 2.25, 95% CI: 1.27, 3.22) and non-HDL-C (β = 0.17, 95% CI: 0.07, 0.26) than children with European ancestry.

CONCLUSIONS

Ethnic differences in CMR were observed in early and middle childhood.

Association between Objectively Determined Physical Activity Levels and Body Composition in 6-8-Year-Old Children from a Black South African Population: BC-IT Study

Physical inactivity in children is a global pandemic in parallel with increasing obesity prevalence. However, studies assessing the association between physical activity (PA) and body composition (BC) report conflicting findings, possibly because of the different methodologies across studies, with objective methods promising reliable results. This study determines the association between objectively determined PA levels and BC in 6–8-year-old children from a black South African population. Ninety-three children aged 6–8 years, who formed part of a larger study on BC using the deuterium dilution method (DDM), were included. Height and weight were measured according to the standard procedures, and body mass index z-score was calculated. Fatness was determined by DDM. An accelerometer was used to measure PA levels. Regression models were performed to determine the relationship between PA and BC. Approximately 23% of the children did not meet the recommended PA guidelines and 27% were overfat. After adjustments were made, more time spent in vigorous PA was significantly associated with lower fat mass (β = −0.25, p = 0.01, 95%CI: −11.08; −1.20) and fat mass % (β = −0.20, p = 0.04, 95%CI: −12.63; −0.18). Participation in high PA, especially of high intensity, was associated with reduced adiposity in children. Behavioural changes such as increasing high intensity PA is strongly recommended for reducing adiposity.