Longitudinal associations between overweight/obesity and stress biology in low-income children

Psychosocial and environmental risk factors of obesity and hypertension in children and adolescents-a literature overview

Childhood obesity has become a worldwide epidemic in the 21st century. Its treatment is challenging and often ineffective, among others due to complex, often not obvious causes. Awareness of the existence and meaning of psychosocial and environmental risk factors seems to be an essential element in the prevention and treatment of obesity and its complications, especially arterial hypertension. In this review, we will discuss the role of that risk factors linking obesity and increased cardiovascular disorders including the role of nutritional factors (including the role of unhealthy diet, inadequate hydration), unhealthy behaviors (e.g. smoking, alcohol and drugs, sedentary behavior, low physical activity, disrupted circadian rhythms, sleep disorders, screen exposure), unfavorable social factors (such as dysfunctional family, bullying, chronic stress, mood disorders, depression, urbanization, noise, and environmental pollution), and finally differences in cardiovascular risk in girls and boys.

Longitudinal Examination of Hair Cortisol Concentrations and Weight Changes in Preschool-Aged Children of Latino Farmworkers

Background: Hair cortisol concentrations may serve as a measure of biologically embedded stress. While the cross-sectional association between hair cortisol and obesity in children has been examined, the data examining this relationship over time are limited. Methods: We examined hair cortisol and anthropometrics in 40 children with obesity from Latino families enrolled in a Head Start program serving farmworkers. All participants were enrolled in a clinical trial using parent mentors to encourage healthy lifestyles. We analyzed the proximal 3 cm of hair at the beginning and the end of the trial, a period of about 8 months. Linear mixed models were used to examine if changes in hair cortisol were associated with changes in adiposity. Results: Children had a median BMI percentile of 98% and parents with lower education with 25 of 40 having less than high school diploma and high food insecurity (17 of 40, 43%). Among the 40 children with valid data for both time points, the median hair cortisol concentration at baseline was 4.09 pg/mg (interquartile range [IQR] 2.65-8.68) and 6.05 pg/mg (IQR 3.95-9.33) at the end point. Increases in cortisol from baseline to follow-up had a small but significant association with decreased obesity over time. Hair cortisol did not moderate an association between food security and weight. Conclusion: In children with chronic stressors and obesity, we found that increases in cortisol over time were associated with decreases in adiposity. Further studies following hair cortisol concentrations over time are needed to understand how this biomarker relates to weight status and stressors. Clinicaltrials.gov ID: NCT03330743.

Associations between chronic stress and hair cortisol in children: A systematic review and meta-analysis

OBJECTIVES

This review systematically examined the associations between chronic stress and hair cortisol concentration (HCC) in children, and the potential modification effects of type, measurement period and scales of chronic stress, child age and sex, hair length and HCC measurement method, characteristics of study site, and congruence between time periods measured for chronic stress and HCC.

METHODS

Pubmed, Wed of Science, and APA PsycINFO were systematically searched for articles examining the association between chronic stress and HCC.

RESULTS

Thirteen studies from five countries with 1,455 participants were included in the systematic review and nine studies were included in the meta-analysis. Meta-analysis revealed that chronic stress was associated with HCC (pooled-r = 0.09, 95 % CI: 0.03, 0.16). Stratified analyses revealed that type, measurement time and scales of chronic stress, hair length and measurement method of HCC, and the congruence between time periods measured for chronic stress and HCC modified such correlations. The positive correlations between chronic stress and HCC were significant for studies measuring chronic stress as stressful life events, assessing chronic stress within the past six months, extracting HCC from 1 cm, 3 cm, or 6 cm of hair, measuring HCC by LC-MS/MS, or having congruence between time periods measured for chronic stress and HCC. The potential modifying effects of sex and country developmental status could not be concluded due to the limited number of studies included.

CONCLUSIONS

Chronic stress was positively correlated with HCC, varying by characteristics and measurements of chronic stress and HCC. HCC could be a biomarker for chronic stress among children.

Stress, Stress Reduction and Obesity in Childhood and Adolescence

BACKGROUND

Obesity in childhood and adolescence remains a great global health challenge. Stress exposure during childhood and adolescence is associated with a higher risk for obesity, yet the linkage between stress and obesity is multidimensional, and its biological and behavioral mechanisms are still not fully understood.

SUMMARY

In this literature review, we identified different types of stress exposure in children and adolescents, including first studied effects of the COVID-19 pandemic as a prolonged stress exposure and their association with obesity risk. We investigated studies on the connection of altered stress biology and behavioral pathways as well as intervention programs on stress reduction in children and adolescents with obesity.

KEY MESSAGES

There is evidence that stress exposure in childhood and adolescence promotes biological and behavioral alterations that contribute to the multifactorial pathogenesis of obesity. COVID-19 related-stress presents the most current example of a negative influence on weight development in children and adolescents. However, longitudinal studies on the linkage between environmental, behavioral, and biological factors across development are few, and results are partly equivocal. Intervention programs to reduce stress in children through mindfulness might be a promising adjunctive tool in the prevention and treatment of childhood and adolescent obesity that could further offer proof of concept of theoretically elaborated cause-and-effect relationships.

Changes in the Prevalence of Overweight and Obesity among Peruvian Children under Five Years before and during the COVID-19 Pandemic: Findings from a Nationwide Population-Based Study

This study aimed to identify changes in the prevalence of childhood (children under five years of age) overweight and obesity in Peru as a whole and at the departmental level, before and during the coronavirus disease (COVID-19) pandemic. We performed a secondary data analysis of two Demographic and Family Health Surveys (2019 and 2021) in Peru. The outcome was childhood overweight and obesity, defined as a weight-for-height score greater than 2 standard deviations. Poisson log generalized linear regression models adjusted for sex and/or age in months of the child were fitted to obtain the prevalence ratios of the changes in childhood overweight and obesity from 2019 to 2021. The analysis included 41,533 (2019: 20,414; 2021: 21,119) participants. The prevalence of childhood overweight and obesity was 6.4% in 2019 and 7.8% in 2021. Female children, aged 2, 3 and 4 years, and mothers who self-identified as non-native, had secondary and higher education, belonged to the middle and richer wealth quintile and resided in an urban area, in a village, in a small city and in the coastal region showed the largest increases in the prevalence of childhood overweight and obesity in 2021 compared to 2019. The departments of Pasco, Apurímac, Junín, Cusco, Lambayeque and La Libertad presented the largest increases in the prevalence of these nutritional disorders. During the pandemic, an increase in the prevalence of childhood overweight and obesity was observed, with demographic and socioeconomic factors accounting for the largest increases in the prevalence rates. A restructuring of overweight and obesity control strategies is required to curb this steady increase.

Glucocorticoids in preterm human milk

Background

Glucocorticoids (GCs), cortisol and cortisone, are essential regulators of many physiological responses, including immunity, stress and mammary gland function. GCs are present in human milk (HM), but whether maternal and infant factors are associated with HM GC concentration following preterm birth is unclear.

Materials and methods

HM samples were collected on postnatal day 5 and 10 and at 4 months’ corrected age (4m CA) in a cohort of moderate- and late-preterm infants. GCs in HM were measured by liquid chromatography-tandem mass spectrometry. Relationships between GCs in HM and both maternal and infant characteristics were investigated using Spearman’s correlations and linear mixed models.

Results

170 mothers of 191 infants provided 354 HM samples. Cortisol concentrations in HM increased from postnatal day 5–4m CA (mean difference [MD] 0.6 ± 0.1 ng/ml, p < 0.001). Cortisone concentration did not change across lactation but was higher than cortisol throughout. Compared to no antenatal corticosteroid (ANS), a complete course of ANS was associated with lower GC concentrations in HM through to 4m CA (cortisol: MD –0.3 ± 0.1 ng/ml, p < 0.01; cortisone MD –1.8 ± 0.4 ng/ml, p < 0.001). At 4m CA, higher maternal perceived stress was negatively associated with GC concentrations in HM (cortisol adjusted beta-coefficient [aβ] –0.01 ± 0.01 ng/ml, p = 0.05; and cortisone aβ –0.1 ± 0.03 ng/ml, p = 0.01), whereas higher postpartum depression and maternal obesity were associated with lower cortisone concentrations (aβ –0.1 ± 0.04 ng/ml p < 0.05; MD [healthy versus obese] –0.1 ± 0.04 ng/ml p < 0.05, respectively). There was a weak positive correlation between GC concentrations in HM and gestational age at birth (r = 0.1, p < 0.05). Infant birth head circumference z-score was negatively associated with cortisol concentrations (aβ –0.01 ± 0.04 ng/ml, p < 0.05). At hospital discharge, fat-free mass showed a weak positive correlation with cortisol concentrations (r = 0.2, p = 0.03), while fat mass showed a weak negative correlation with cortisone concentrations (r = –0.25, p < 0.001).

Conclusion

The mammary gland appears to protect the infant from cortisol through inactivation into cortisone. Maternal and infant characteristics were associated with concentration of GCs in HM, including ANS, stress and depression scores, obesity, gestational age and infant size. The effects of HM glucocorticoids on long-term health outcomes requires further research.

Associations Between Different Cortisol Measures and Adiposity in Children: A Systematic Review and Meta-Analysis

This study examined associations between hair, salivary, serum, and urinary cortisol concentration with adiposity-related indicators in children, and explored their potential effects modification by age, sex, cortisol measurement method, and country developmental context. We systematically searched PubMed, Web of Science, and Embase for studies examining at least one of the four aforementioned cortisol with objectively measured adiposity-related outcomes in children. Meta-analyses of cross-sectional studies revealed that hair cortisol concentration was associated with fat mass index (FMI)-standard deviation score (SDS)/FMI z-score (pooled-β = 0.04, 95% CI: 0.01, 0.08) and BMI/BMI z-score (pooled-β = 0.15, 95% CI: 0.06, 0.25), and these associations were significant among children aged ≤ 12 years (pooled-β = 0.15, 95% CI: 0.05, 0.26) and >12 years (pooled-β = 0.13, 95% CI: 0.04, 0.22), children from developed countries (pooled β = 0.12, 95% CI: 0.03, 0.21) and developing countries (pooled-β = 0.193, 95% CI: 0.188, 0.198), and in studies extracting cortisol via LC-MS/MS (pooled-β = 0.18, 95% CI: 0.06, 0.29) but not ELISA (pooled-β = 0.08, 95% CI: −0.06, 0.22). Meta-analyses of both cohort and cross-sectional studies revealed non-significant associations of morning salivary cortisol concentration and total daily cortisol output with BMI/BMI z-score. Serum cortisol concentration was not associated with BMI or waist circumference. Meta-analysis of urinary cortisol concentration and adiposity was hindered by insufficient data. These findings further corroborate understanding of chronic stress’ physiological contribution to increased pediatric obesity risk.

Obesity and COVID-19 in Children and Adolescents: Reciprocal Detrimental Influence—Systematic Literature Review and Meta-Analysis

The dramatic lifestyle changes forced by COVID-19-related lockdown promoted weight gain, with a stronger impact on obese subjects, at higher risk of severe infection. The PubMed database was searched to identify original studies assessing: (1) the extent and risk factors of lockdown-induced weight increase; and (2) the impact of obesity on the risk of hospital admission in children and adolescents. A systematic literature review and meta-analyses were performed. Twenty out of 13,986 identified records were included. A significant weight increase was reported in the majority of subjects, with no apparent gender or age differences. It was induced by a higher consumption of hypercaloric/hyperglycemic/junk food and/or the reduction of physical activity, often associated with an altered sleep–wake cycle. On the other hand, obesity increased the risk of hospitalization (OR = 4.38; 95% C.I. 1.46–13.19; p = 0.009; I² = 96%) as compared to the normal weight population. COVID-19 and obesity represent epidemic conditions with reciprocal detrimental impact. Urgent public health interventions, targeting the various age and social strata, and involving governmental authorities, health care personnel, teachers and families are warranted to increase awareness and actively promote healthy lifestyles to contrast pediatric obesity and its detrimental consequences at a global level.

Difference in Hair Cortisol Concentrations between Obese and Non-Obese Children and Adolescents: A Systematic Review

Childhood obesity has been linked to physical and psychological comorbidities that can be carried into adulthood. A bidirectional link between body weight and the stress system appears to exist, as cortisol may affect the regulation of appetite, while adiposity can affect cortisol secretion. Among the biological tissues used to evaluate cortisol concentrations, scalp hair can provide retrospective measures. The aim of this systematic review was to investigate the difference in hair cortisol concentrations between obese and non-obese minors ≤ 19 years of age. Children and adolescents with genetic, somatic or psychiatric comorbidities were excluded. The work was conducted following the PRISMA guidelines, using prespecified search terms in the Pubmed database. The initial search yielded 56 studies, while the last step of the screening procedure concluded in 9 observational studies. Among them, the results could be characterized as inconclusive. Five of them demonstrated significantly higher hair cortisol concentrations in obese children and adolescents than normal weight subjects. On the contrary, the remaining four found no statistically significant differences in hair cortisol concentrations between obese and non-obese subjects. Different methodologies applied, and confounding factors could explain the inconsistency in the findings. Further research is needed to provide more solid results.

Stressed out and fed up: The effect of stress on maternal feeding behaviors and the moderating role of executive function

Stress is associated with a range of unhealthy eating habits, yet few studies have examined how stress may influence the intergenerational transmission of eating habits from parents to their children. Specifically, there is a lack of data regarding the role of stress on feeding practices. Moreover, most work investigating the associations between parental stress and their feeding behaviors has been correlational, limiting our understanding of causality. In the current study, we used an experimental design, induced high and low stress in mothers using a standard laboratory stressor, and observed mother-child interactions during a snack break. We also examined the potential role of maternal executive functioning (EF) for buffering the effects of stress on maternal feeding behaviors. Levels of maternal stress were manipulated with the Trier Social Stress Task (TSST) in a community sample (N = 80 dyads, Child M_age = 41.89 months, female = 43). We measured maternal EF with a series of computerized tasks. Maternal feeding behaviors were coded for controlling behaviors, which included pressuring and restricting behaviors. Results indicate a main effect of stress on controlling feeding behaviors, such that mothers in the high-stress condition exhibited higher levels of controlling behaviors. The effect of stress on controlling feeding behaviors was ameliorated among mothers with higher levels of EF after controlling for child age and income. Results provide causal evidence for the role of stress on feeding behaviors and suggest EF as a factor to be considered in the treatment and prevention of diet-related illnesses.

The Impact of Stress on Health in Childhood and Adolescence in the Era of the COVID-19 Pandemic

BACKGROUND

The ongoing pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is posing many challenges to global health. Efforts from the whole scientific community have shed light on the pathogenetic mechanisms and the clinical features of SARS-CoV-2 infection as well as on potential therapeutic strategies.

SUMMARY

The consequences of stress related to social isolation and anxiety generated by the pandemic on mental and physical health are collateral effects that are yet poorly investigated.

A practical approach to obesity prevention: Healthy home habits

ABSTRACT

Families have the potential to foster a healthy home environment aimed at reducing the risk of overweight and obesity. Establishing habits associated with reduced risk of obesity and overweight early in childhood can have lasting effects into adulthood. Nurse practitioners can encourage families to participate in healthy habits by addressing areas of growth for obesity prevention within the home. A review of the most recent literature, approximately over the past decade, was used to provide a consolidated source of reference for healthy home habits for the nurse practitioner. The search included terms such as "obesity," "overweight," "healthy habits," "physical activity," "obesogenic behaviors," "family meals," "screen time," "depression," "sugary beverages," and "portion sizes." The information was synthesized into three content areas: nutrition and consumption, patterns of activity, and stress within the home. Establishing healthy habits early in life can protect against the development of overweight and obesity. Nurse practitioners can serve a vital role in the prevention of pediatric, adolescent, and adult obesity. Equipped with the unique role of assisting those from a diverse patient base, nurse practitioners can inform patients how to improve healthy habits to decrease the likelihood of obesity or overweight. Encouraging behavior change related to the healthy habits associated with the prevention of overweight and obesity can have a long-term impact on the health of an entire family.

Diffusion of scientific concepts on obesity in the global context: a historical review

ABSTRACT This article aimed to carry out a historical analysis of the dissemination of the scientific concepts on obesity, overweight and excess weight in the field of nutritional epidemiology in the world. The methodological procedures comprised: (1) Systematic search in the PubMed® database using single keywords and without date filter; (2) Documentary analysis of normative instruments on the websites of the World Health Organization, the Centers for Disease Control and Prevention and the World Obesity Federation; and (3) Analysis of the scientific production of scientists participating in the obesity classification of the International Obesity Task Force. The historical analysis showed that, considering the volume of publications on obesity, it appears that in the 1940-1949 decade the problem of obesity emerged on the world scenario. From the number of publications issued in the last 20 years, which corresponds to 85% of the investigated period, we can deduct that scientists’ concern to investigate the subject as a phenomenon coincides with the World Health Organization declaration of obesity as a global epidemic issued in the year 2000. In accordance with normative procedures established by international organizations, there has been a hegemonic use of the concepts of obesity and overweight, in this order of priority, by scientists worldwide. The concept of excess weight has experienced a relative rise since the year 2000, but its use has been very restricted, expressing dissonance in face of the recommendations of international standardization organizations, a fact that suggests discussion and review of its use by the world scientific community.

Food Addiction and Psychosocial Adversity: Biological Embedding, Contextual Factors, and Public Health Implications

The role of stress, trauma, and adversity particularly early in life has been identified as a contributing factor in both drug and food addictions. While links between traumatic stress and substance use disorders are well documented, the pathways to food addiction and obesity are less established. This review focuses on psychosocial and neurobiological factors that may increase risk for addiction-like behaviors and ultimately increase BMI over the lifespan. Early childhood and adolescent adversity can induce long-lasting alterations in the glucocorticoid and dopamine systems that lead to increased addiction vulnerability later in life. Allostatic load, the hypothalamic-pituitary-adrenal axis, and emerging data on epigenetics in the context of biological embedding are highlighted. A conceptual model for food addiction is proposed, which integrates data on the biological embedding of adversity as well as upstream psychological, social, and environmental factors. Dietary restraint as a feature of disordered eating is discussed as an important contextual factor related to food addiction. Discussion of various public health and policy considerations are based on the concept that improved knowledge of biopsychosocial mechanisms contributing to food addiction may decrease stigma associated with obesity and disordered eating behavior.

Exploring the Temporal Relation between Body Mass Index and Corticosteroid Metabolite Excretion in Childhood

Childhood obesity is associated with alterations in hypothalamus–pituitary–adrenal (HPA) axis activity. However, it is unknown whether these alterations are a cause or a consequence of obesity. This study aimed to explore the temporal relationship between cortisol production and metabolism, and body mass index (BMI). This prospective follow-up study included 218 children (of whom 50% were male), born between 1995 and 1996, who were assessed at the ages of 9, 12 and 17 years. Morning urine samples were collected for assessment of cortisol metabolites by gas chromatography-tandem mass spectrometry, enabling the calculation of cortisol metabolite excretion rate and cortisol metabolic pathways. A cross-lagged regression model was used to determine whether BMI at various ages during childhood predicted later cortisol production and metabolism parameters, or vice versa. The cross-lagged regression coefficients showed that BMI positively predicted cortisol metabolite excretion (p = 0.03), and not vice versa (p = 0.33). In addition, BMI predicted the later balance of 11β-hydroxysteroid dehydrogenase (HSD) activities (p = 0.07), and not vice versa (p = 0.55). Finally, cytochrome P450 3A4 activity positively predicted later BMI (p = 0.01). Our study suggests that changes in BMI across the normal range predict alterations in HPA axis activity. Therefore, the alterations in HPA axis activity as observed in earlier studies among children with obesity may be a consequence rather than a cause of increased BMI.

Children's implicit food cognition: Developing a food Implicit Association Test

Assessing children's reasoning about food, including their health knowledge and their food preferences, is an important step toward understanding how health messages may influence children's food choices. However, in many studies, assessing children's reasoning relies on parent report or could be susceptible to social pressure from adults. To address these limitations, the present study describes the development of a food version of the Implicit Association Test (IAT). The IAT has been used to examine children's implicit stereotypes about social groups, yet few studies have used the IAT in other domains (such as food cognition). Four- to 12-year-olds (n = 123) completed the food IAT and an explicit card sort task, in which children assessed foods based on their perception of the food's healthfulness (healthy vs. unhealthy) and palatability (yummy vs. yucky). Surprisingly, children demonstrated positive implicit associations towards vegetables. This pattern may reflect children's health knowledge, given that the accuracy of children's healthfulness ratings in the card sort task positively predicted children's food IAT d-scores. Implications for both food cognition and the IAT are discussed.