Associations Between Sedentary Time, Physical Activity, and Cardiovascular Health in 6-Year-Old Children Born to Mothers With Increased Cardiometabolic Risk.

PURPOSE: To assess associations between sedentary time (ST), physical activity (PA), and cardiovascular health in early childhood. METHOD: Cross-sectional study including 160 children (age 6.1 y [SD 0.5], 86 boys, 93 maternal body mass index ≥ 30 kg/m2, and 73 gestational diabetes) assessed for pulse wave velocity, echocardiography, ultra-high frequency 48-70 MHz vascular ultrasound, and accelerometery. RESULTS: Boys had 385 (SD 53) minutes per day ST, 305 (SD 44) minutes per day light PA, and 81 (SD 22) minutes per day moderate to vigorous PA (MVPA). Girls had 415 (SD 50) minutes per day ST, 283 (SD 40) minutes per day light PA, and 66 (SD 19) minutes per day MVPA. In adjusted analyses, MVPA was inversely associated with resting heart rate (ß = -6.6; 95% confidence interval, -12.5 to -0.7) and positively associated with left ventricular mass (ß = 6.8; 1.4-12.3), radial intima-media thickness (ß = 11.4; 5.4-17.5), brachial intima-media thickness (ß = 8.0; 2.0-14.0), and femoral intima-media thickness (ß = 1.3; 0.2-2.3). MVPA was inversely associated with body fat percentage (ß = -3.4; -6.6 to -0.2), diastolic blood pressure (ß = -0.05; -0.8 to -0.1), and femoral (ß = -18.1; -32.4 to -0.8) and radial (ß = -13.4; -24.0 to -2.9) circumferential wall stress in boys only. ST and pulse wave velocity showed no significant associations. CONCLUSIONS: In young at-risk children, MVPA is associated with cardiovascular remodeling, partly in a sex-dependant way, likely representing physiological adaptation, but ST shows no association with cardiovascular health in early childhood.

Childhood cardiovascular morphology and function following abnormal fetal growth.

Studies examining the link between abnormal fetal growth and cardiac changes in childhood have presented conflicting results. We studied the effect of abnormal fetal growth on cardiac morphology and function during childhood, while controlling for body size, composition and postnatal factors. We report on the follow-up of 90 children (median age 5.81 years, IQR 5.67; 5.95) born appropriate for gestational age (AGA, N = 48), small for gestational age (SGA, N = 23), or large for gestational age (LGA, N = 19); SGA and LGA defined as birth weight Z-score < - 2 and > + 2, respectively. We examined the heart using echocardiography, including Doppler and strain imaging, in relation to anthropometrics, body composition, blood pressure, physical activity, and diet. Although groupwise differences in body size decreased during the first year after birth, LGA remained larger at follow-up, with higher lean body mass and BMI, while SGA were smaller. Slight changes in left ventricular diastolic function were present in SGA and LGA, with SGA showing increased mitral diastolic E- and A-wave peak flow velocities, and increased septal E/E' ratio, and LGA showing larger left atrial volume adjusted for sex and lean body mass. In univariate analyses, lean body mass at follow-up was the strongest predictor of cardiac morphology. We found no groupwise differences at follow-up for ventricular sphericity, cardiac morphology adjusted for lean body mass and sex, or blood pressure, diet, or physical activity. Cardiac morphology is predicted by lean body mass during childhood, even in the setting of abnormal fetal growth. Our results are consistent with a limited effect of fetal programming on cardiac dimensions during childhood. Minor changes in diastolic function are present in both SGA and LGA children, however, the clinical significance of these changes at this stage is likely small.

Arterial health during early childhood following abnormal fetal growth.

BACKGROUND: Abnormal fetal growth is associated with increased cardiovascular risk in adulthood. We investigated the effect of fetal programming on arterial health and morphology during early childhood. METHODS: We examined 90 children (median age 5.81 years, interquartile range: 5.67; 5.95), born small for gestational age with fetal growth restriction, large or appropriate for gestational age (SGA, N = 23, LGA, N = 19, AGA N = 48). We measured body composition, anthropometrics, blood pressure, pulse wave velocity (PWV), lipids, glucose and inflammatory markers, and assessed carotid, brachial, radial and femoral arterial morphology and stiffness using very-high resolution ultrasound (46-71 MHz). RESULTS: LGA showed increased anthropometry, lean body mass and body mass index. SGA displayed decreased anthropometry and lean body mass. Blood pressure, PWV, carotid artery stiffness and blood work did not differ groupwise. Differences in lumen diameters, intima-media thicknesses (IMT) and adventitia thicknesses disappeared when adjusted for lean body mass and sex. In multiple regression models arterial dimensions were mainly predicted by lean body mass, with birth weight remaining associated only with carotid and brachial lumen dimensions, and not with IMTs. Carotid-femoral PWV was predicted by height and blood pressure only. No independent effect of adiposity was observed. CONCLUSIONS: Arterial dimensions in childhood associate with current anthropometrics, especially lean body mass, and sex, explaining differences in arterial layer thickness. We found no signs of fetal programming of cardiovascular risk or arterial health in early childhood.

Neonatal Arterial Morphology Is Related to Body Size in Abnormal Human Fetal Growth.

BACKGROUND: Restriction in fetal growth is associated with cardiovascular disease in adulthood. It is unclear whether abnormal intrauterine growth influences arterial morphology during the fetal or neonatal stage. The objective was to study the regional arterial morphology with respect to gestational age and abnormal fetal body size. METHODS AND RESULTS: We studied body anthropometrics and arterial morphology and physiology in 174 neonates born between 31 and 42 weeks of gestation, including neonates with birth weights appropriate, small, and large for age, with very high resolution vascular ultrasound (35-55 MHz). In simple linear regressions, parameters of body size (body weight, body surface area, and organ circumference) and gestational age were statistically significantly associated with common carotid, brachial, femoral arterial parameters (lumen diameter [LD], wall layer thickness [intima-media thickness and intima-media-adventitia thickness], and carotid artery wall stress [CAWS]). Male sex was statistically significantly associated with LD and CAWS. In multiple linear regression models, body size, gestational age, and sex explained a large proportion of the arterial variance (R( 2) range, 0.37-0.47 for LD; 0.09-0.35 for intima-media thickness; 0.21-0.41 for intima-media-adventitia thickness; and 0.23 for CAWS; all models P<0.001). Arterial wall layer thickness, LDs, and CAWS were independently and strongly predicted by body size, and no effect of maternal disease was observed when added to the models. Gestational age and male sex were also independently but more weakly associated with arterial LDs and CAWS (P<0.01), but not with arterial wall layers. CONCLUSIONS: These results indicate that the intrauterine growth of fetal arterial LD and wall layer thickness are primarily attributed to body growth overall. LD and CAWS show weaker association with gestational age and sex.

Feasibility and precision of transcutaneous very-high resolution ultrasound for quantification of arterial structures in human neonates - comparison with conventional high resolution vascular ultrasound imaging.

BACKGROUND: Non-invasive transcutaneous very-high resolution ultrasound (VHRU, 25-55 MHz) has recently been developed to quantify superficial vascular structures in humans. The performance of the method has yet not been evaluated in vivo in neonates. The aim of the study was to compare VHRU with conventional high-resolution ultrasound (HRU, 7-12 MHz), and to assess the feasibility and precision of VHRU in this population. METHODS: 150 images from central elastic (common carotid, CCA) and peripheral muscular (brachial, BA; femoral, FA) arteries were obtained in 25 neonates of different gestational ages (range 33 + 0 to 41 + 5 gestational weeks) and weights (range 1570-4950 g) with VHRU, and the use of HRU for comparison assessed in five. RESULTS: Images were captured from CCAs with 35 MHz, FAs using 35 and 55 MHz, and BAs using 55 MHz. 12 MHz was unable to assess FAs and BAs, and the CCA IMT was grossly overestimated compared with 35-55 MHz. IMTs of the smallest BAs and FAs were beyond the axial resolution of VHRU (<0.05 mm), thus immeasurable. For VHRU, the intra-, inter- and test-retest coefficients of variation (CV) were for LDs (range 1.44-2.62 mm, CVs between 1.6 and 4.8%), IMATs (range 0.141-0.161 mm, CVs between 8.8 and 19.9%), and IMTs (range 0.062-0.165 mm, CVs between 12.8 and 24.8%) for the different arteries. CONCLUSION: VHRU is feasible, accurate and precise in the assessment of superficial proximal conduit arteries but unable to assess the abdominal aorta in human neonates HRU-derived neonatal conduit arterial wall layer thicknesses are below the ultrasound axial resolution.