Is BMI a relevant marker of fat mass in 4 year old children? Results from the MINISTOP trial

Hyperactivity in preschool age is associated with higher fat-free mass and healthy lifestyle behaviours five years later: A longitudinal study of Swedish children

BACKGROUND

There is evidence for a link between hyperactivity and obesity, especially among older children. Both conditions seem to be multifactorial in origin and hypotheses of common underlying issues, such as emotional dysregulation, have been suggested. However, studies of the co-occurrence of the two conditions in younger age groups have been inconclusive.

OBJECTIVES

We aimed to study the longitudinal associations of psychological strengths and difficulties at 4 years of age with health behaviours, body composition, physical fitness, and cardiovascular disease (CVD) risk factors 5 years later.

METHODS

Parents of 226 4-year-old children filled out the Strengths and Difficulties Questionnaire (SDQ). At 9 years of age, we assessed health behaviours, physical fitness, body composition, and CVD risk factors. Associations were examined with linear regression models that were adjusted for sex, age of the child at 9, and maternal education.

RESULTS

In the adjusted models, hyperactivity at 4 was associated with higher fat-free mass (β = 0.18, p = 0.007) and lower levels of sedentary behaviour (β -0.14, p = 0.043) at 9 years. Furthermore, greater emotional problems at 4 were associated with lower intake of fruit and vegetables (β -0.14, p = 0.038) at 9 years. However, there were no statistically significant associations between psychological difficulties and fat-mass index.

CONCLUSIONS

Our novel data provide no evidence of an association between hyperactivity in preschool age and obesity or obesity-related behaviours in school age. Future studies examining how psychological factors relate to obesity development should consider a developmental perspective.

Subcutaneous Adipose Tissue Measured by B-Mode Ultrasound to Assess and Monitor Obesity and Cardio-Metabolic Risk in Children and Adolescents

Simple Summary

The prevention and treatment of childhood and adolescent overweight and obesity raises the need for accurate body fat assessment. Precise methods are at high technical expense, require exposure to ionizing radiation and are limited to institutional investigations, while common body indicators fail to identify excess body fat. Subcutaneous adipose tissue measured by ultrasound is an alternative approach, which was evaluated in relation to commonly applied body indicators to assess cardio–metabolic risk and its applicability in the field. Subcutaneous adipose tissue measured by ultrasound indicated a clear advantage over commonly applied body indicators and implies that severe body fat assessment errors are to be expected when BMI is used as a measure for body fatness in children. Children or adolescents with identical BMIs may have large differences (>200%) in their amount of subcutaneous adipose tissue. Ultrasound provides an easily applicable, reliable and safe method for accurate assessment of obesity and monitoring treatment responses in children and adolescents at cardio–metabolic risk.

Abstract

Monitoring of children at heightened risk of cardio–metabolic diseases raises the need for accurate assessment of obesity. A standardized approach for measuring subcutaneous adipose tissue (SAT) by bright-mode ultrasound was evaluated in relation to body indices and anthropometry in a cross-sectional sample of 76 South African children (7–10 years) and 86 adolescents (13–17 years) to assess cardio–metabolic risk. SAT was higher in girls as compared to boys (children: 50.0 ± 21.7 mm > 34.42 ± 15.8 mm, adolescents: 140.9 ± 59.4 mm > 79.5 ± 75.6 mm, p < 0.001) and up to four times higher in adolescents than in children. In children, measures of relative body weight showed only a poor correlation to SAT (BMI: r = 0.607, p < 0.001), while in adolescents, BMI correlated high with SAT (r = 0.906, p < 0.001) based on high rates of overweight and obesity (41.8%). Children with identical BMIs may have large differences (>2–3-fold) in their amount of SAT. The moderate association to systolic (r = 0.534, r = 0.550, p < 0.001) and diastolic blood pressure (r = 0.402, r = 0.262, p < 0.001) further substantiates that SAT measured by ultrasound provides an accurate, safe and easy applicable approach for monitoring in children and adolescents at cardio–metabolic risk.

Associations of mothers' source of feeding information with longitudinal trajectories of sugar-sweetened beverage intake, 100% juice intake and adiposity in early childhood

BACKGROUND

There remains a need to understand how information sources can promote young children's healthy beverage consumption and prevent obesity.

OBJECTIVES

To examine associations of mothers' primary feeding information source with children's sugar-sweetened beverage (SSB) intake, 100% juice intake and adiposity between ages 3 and 7 years.

METHODS

We analyzed data from a prospective cohort study (n = 371 children; 13 visits). Mothers reported their primary feeding information source at baseline and completed child 3-day dietary records each visit. Child adiposity indicators were calculated from repeated height/weight measurements and dual-energy X-ray absorptiometry. Longitudinal models examined beverage intakes and adiposity over time by source.

RESULTS

Primary feeding information sources included doctors (48.2%), mothers (17.5%), grandmothers (13.5%), other healthcare professionals (11.3%) and other family/friends (9.4%). Children's juice intake with age differed by source (P interaction = 0.03), with steepest and slightest intake decreases in the doctor (-19.7% each year; 95% CI: -23.7%, -15.5%) and grandmother (-5.0%; -14.5%, 5.5%) subgroups, respectively. Children's SSB intake did not differ by source, but increased annually by 7.1% (4.5%, 9.8%) overall. The grandmother subgroup had the greatest child adiposity over time.

CONCLUSIONS

Mothers' primary feeding information source may have important, yet heterogeneous, influences on young children's beverage intakes and adiposity over time. Consistent evidence-based messages are likely needed.

Hyperactivity is associated with higher fat-free mass and physical activity in Swedish preschoolers: A cross-sectional study

Aim

We investigated psychological strengths and difficulties in a Swedish population of preschool children and analysed how these behavioural variables were related to body composition, cardiorespiratory fitness, physical activity levels, sedentary behaviour and diet.

Methods

Three hundred and fifteen boys and girls were recruited during 2014‐2015. Body composition was measured using air‐displacement plethysmography, and anthropometric measures were taken. Parents responded to questions about age, sex and educational attainment, diet, physical activity levels and smoking habits, as well as the Strengths and Difficulties Questionnaire (SDQ). Regression models were created to analyse associations between psychological variables, body composition and health behaviours.

Results

Hyperactivity scores were positively related to fat‐free mass (β = 0.20, P = .001) and moderate‐to‐vigorous physical activity (β = 0.16, P = .003) and negatively associated with sedentary behaviours (β = 0.18, P = .001), but showed no statistically significant associations with fat mass.

Conclusion

Our findings suggest that the adverse health consequences of hyperactivity on obesity and obesity‐related health behaviours may be established after the preschool period. Questions about the time frame of contributing and modulating factors in obesity development are discussed.

Changes in body composition by age and obesity status in preschool-aged children: the STEPS study

BACKGROUND/OBJECTIVES

Obesity in early childhood is associated with increased risk of chronic diseases, but studies of body composition at preschool ages are sparse. Therefore, we examined differences in body composition by sex and obesity status in Finnish preschool-aged children and within-individual changes in body composition in normal and overweight children.

SUBJECT/METHODS

Body composition was measured using segmental multifrequency bioimpedance analysis (BIA) in 476 children and in 781 children at age 3 and 5 years, respectively. Of those, 308 had repeated BIA measurements at both ages. BMI-SDS was used for classification of normal weight and overweight children.

RESULTS

Sex difference in the amount of lean mass (LM) was already seen at 3 years of age (boys 11.7 kg, girls 11.3 kg; p < 0.001). At 5 years of age, boys had lower fat mass (FM; 3.6 kg vs. 3.9 kg, p < 0.001), lower percent fat mass (%FM; 17.2% vs. 19.1%; p < 0.001), and higher LM (16.0 kg vs. 15.2 kg; p < 0.001) than girls. Overweight children had higher values in FM, %FM, and LM compared with normal weight peers at both ages. Among normal weight children, the increase of LM by age was associated with only minor changes in FM, whereas children who were or became overweight both LM and FM was substantially increased between 3 and 5 years of age.

CONCLUSIONS

BIA-assessed body composition differs by sex and obesity status already at age of 3 years. For children who are or become overweight at very young age, the patterns for the changes in LM and FM by age are different than for normal weight children.

Fat and fat-free mass of healthy Swedish children show tracking during early life, but there are differences

AIM

Obesity may start early in life. We investigated relationships between size and body composition variables in infancy and at 4 years of age using valid estimates of body composition. The results were compared to those obtained when body mass index (BMI) was used to estimate body fatness at 4 years.

METHODS

Using air displacement plethysmography, size, fat mass and fat-free mass were studied, between 2007 and 2015, in 253 full-term healthy Swedish children at 1 week, 12 weeks and 4 years of age.

RESULTS

Positive associations between variables in infancy and at 4 years were found at 1 and 12 weeks for weight, height, BMI, fat-free mass and fat-free mass index (p ≤ 0.002) and for fat mass, per cent body fat and fat mass index (p ≤ 0.04) at 12 weeks. Fat mass gained during infancy correlated positively (p ≤ 0.031) with per cent fat mass, fat mass index and BMI, all at 4 years. In girls, gains in fat-free mass during infancy correlated with BMI (p = 0.0005) at 4 years.

CONCLUSION

The results provide information regarding body composition trajectories during early life and demonstrate limitations of BMI as a proxy for body fatness when relating early weight gain to variables, relevant for later obesity risk.

Physical fitness in relation to later body composition in pre-school children

OBJECTIVES

Although physical fitness is considered a marker of health in youth, little is known whether physical fitness in pre-school age is related to later body composition. Thus, this study investigated (i) associations of physical fitness at 4.5years of age with body composition 12months later and (ii) whether improvements in physical fitness during the 12-month follow-up were associated with changes in body composition.

DESIGN

This study included 142 children, measured at 4.5 and 5.5years, from the control group of the MINISTOP trial.

METHODS

Physical fitness (cardiorespiratory fitness, lower- and upper-body muscular strength and motor fitness) was measured using the PREFIT test battery. Body composition was assessed using air-displacement plethysmography.

RESULTS

In adjusted regression analyses, greater cardiorespiratory fitness, lower-body muscular strength and motor fitness at 4.5years were associated with a lower fat mass index at 5.5years (standardized β=-0.182 to -0.229, p≤0.028). Conversely, greater cardiorespiratory fitness, lower- and upper-body muscular strength as well as motor fitness at 4.5years of age were associated with a higher fat-free mass index (standardized β=0.255-0.447, p≤0.001). Furthermore, improvements in cardiorespiratory fitness, lower-body muscular strength and motor fitness during the 12-month follow-up period were associated with decreases in fat mass index and/or % fat mass.

CONCLUSIONS

In conclusion, the results of this study provide evidence of the importance of physical fitness early in life. Nevertheless, further studies are needed in order to clarify the influence of physical fitness in the pre-school age with later health outcomes.