Overweight and obese children have lower cortisol levels than normal weight children

Nocturnal Salivary Cortisol Is an Accurate Non-Invasive Test to Assess Endogenous Hypercortisolism in Children with Obesity and a Clinical Phenotype Suspicious for Cushing's Syndrome

INTRODUCTION

Cushing's syndrome (CS) constitutes one of the most challenging diagnostic assessments for paediatric endocrinologists. The clinical presentation of some children with exogenous obesity overlaps with those observed in hypercortisolism states. Accurate, non-invasive first-line tests are necessary to avoid false-positive results in the obese. We aimed to evaluate the diagnostic accuracy of salivary cortisol to assess endogenous hypercortisolism in children with obesity and clinical overlapping signs of CS.

METHODS

Case-control study that included children aged 2-18 years, BMI-SDS ≥2.0 and a follow-up >2 years. Patients were assigned to three categories: group A, features strongly indicative of paediatric CS (growth failure combined with increasing weight); group B, features suggestive of CS (e.g., moon face and striae); and group C, less specific features overlapping with CS (e.g., hypertension, hirsutism, insulin resistance). Children in categories A and B formed the control group. Ten patients with confirmed CS were the case group. All children collected saliva samples on the same day in the morning between 7 and 8:00 a.m. (morning salivary cortisol: mSC) and at 11 p.m. (nocturnal salivary cortisol: nSC). The mSC and nSC results were used to calculate the percentage decrease of cortisol at night (%D). Main outcomes by receiver operating characteristic for nSC and the %D were sensitivity, specificity, positive (P) and negative (N) predictive values (PV) and their corresponding 95% CI. Salivary cortisol was measured by electrochemiluminescence assay (lower limit of quantification: 2.0 nmol/L).

RESULTS

75/112 children met the inclusion criteria, whereas 22/75 children were eligible for the control group. Only controls decreased nSC (median and interquartile range: 2.0 [2.0-2.5] nmol/L) compared to mSC (6.9 [4.8-10.4] nmol/L), p < 0.0001. A cut-off for nSC ≥8 nmol/L confirmed CS within a sensitivity: 1.0 (0.69-1.0), specificity: 1.0 (0.85-1.0), PPV: 1.0 (0.69-0.99), and NPV: 1.0(0.85-0.99), achieving a diagnostic efficiency of 100%. The cut-off obtained for %D was 50%. No child with CS had a %D ≥50%, but 6/22 children in the control group had a %D below the cut-off, resulting in a lower overall diagnostic accuracy of 81% compared to nSC.

CONCLUSION

Salivary cortisol at 11 p.m. is an accurate, feasible, and non-invasive first-line test to assess endogenous hypercortisolism in children with obesity and clinical suspicion of CS. The nSC was also useful in showing that the circadian rhythm of cortisol was preserved in children with exogenous obesity. In patients with nSC ≥8.0 nmol/L, other biochemical assessments and imaging studies are needed to further confirm the aetiology.

Hair cortisol levels are associated with overweight and obesity in the ELSA-Brasil cohort

Introduction

Hair cortisol level has recently been identified as a promising marker for detecting long-term cortisol levels and a marker of hypothalamic-pituitary-adrenal cortex (HPA) axis activity. However, research on the association between obesity and an altered cortisol metabolism remains controversial.

Objective

This study aimed to investigate the relationship between hair cortisol levels and overweight and obesity in participants from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

Methods

This was a cross-sectional study involving 2,499 participants from the second follow-up (visit 3, 2017-2019) attending research centers in Rio de Janeiro and Rio Grande do Sul states. Hair samples were collected, and cortisol levels were analyzed using enzyme-linked immunosorbent assay (ELISA) kits. Cortisol levels were classified as low (< 40 pg/mg), medium (40-128 pg/mg), or high (> 128 pg/mg). The participants were classified as eutrophic, overweight, or obese according to their weight (kg) and height (m2). Odds ratios (ORs) with 95% confidence intervals (95%CI) were estimated.

Results

Of the 2499 individuals, 30% had eutrophic weight, 40% were overweight, and 30% were obese. Notably, cortisol levels gradually increased with increasing body weight. Among participants with high hair cortisol levels, 41.2% were classified as overweight and 34.2% as obese. Multinomial logistic regression analysis indicated that participants with high cortisol levels were 43% (OR =1.43; 95%CI: 1.02-2.03) more likely to be overweight and 72% (OR =1.72; 95%CI:1.20-2.47) more likely to be obese than participants with low hair cortisol levels. After adjustment for all covariates, high cortisol levels remained associated with obesity (OR = 1.54; 95%CI:1.02-2.31) and overweight (OR =1.33; 95%CI:0.91-1.94).

Conclusion

In the ELSA-Brazil cohort, hair stress were positively associated with overweight and obesity. These results underscore the importance of considering stress and cortisol as potential factors in obesity prevention and intervention efforts, and highlight a novel aspect of the complex relationship between stress and obesity in the Brazilian population.

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.

The Effect of Neighborhood-level Resources on Children's Physical Development: Trajectories of Body Mass Index and Pubertal Development and the Influence of Child Biological Sex

Growing research substantiates the role of neighborhood disadvantage in contributing to early pubertal maturation and higher body mass index; however, previous studies in this area have design limitations. Specifically, many studies have been cross-sectional, have used singular indicators of neighborhood disadvantage (e.g., poverty), and have provided mixed findings about the role of biological sex. The present study addresses these gaps by examining how neighborhood resources (spanning educational, health/environmental, and social/economic domains) predict trajectories of pubertal maturation and body mass index using longitudinal multi-wave data. Furthermore, multigroup analyses assessed how these associations may differ by child biological sex. Participants in this study (n = 505; 54% male) were assessed every 3 years at age 9 (M = 9.17, SD = 0.39), age 12 (M = 12.63, SD = 0.43), and age 15 (M = 15.23, SD = 0.37). Approximately 12% of the sample identified as Hispanic, and 11% as non-White. Using multigroup latent growth analyses, the study examined how neighborhood resources predicted trajectories of pubertal maturation and body mass index using multi-wave data across middle childhood through mid-adolescence. The findings suggested that greater neighborhood resources were cross-sectionally associated with lower pubertal development and predicted slower trajectories across time. Although all girls in the study eventually progressed through pubertal development, girls in lower resourced neighborhoods experienced a much earlier onset of puberty. Additionally, greater neighborhood resources predicted lower BMI both cross sectionally and longitudinally. Specifically, higher resourced neighborhoods were protective against obesity risk for both boys and girls across mid-childhood through mid-adolescence. In sum, the study highlights the role of broader neighborhood factors on early maturity risk for female children, and obesity risk for children regardless of biological sex.

Clinical and biological correlates of morning serum cortisol in children and adolescents with overweight and obesity

Background and aim

A fraction of children with obesity have increased serum cortisol levels. In this study, we describe the clinical characteristics of obese children and adolescents with elevated morning serum cortisol levels and the relationship between the cortisol levels and components of the metabolic syndrome.

Methods

Retrospective medical record review study of children aged 4 to 18 years with overweight or obesity seen for obesity management in the Pediatric Obesity Clinic of the UZ Brussel between 2013 and 2015.

Results

A total of 234 children (99 boys and 135 girls) with overweight (BMI z-score > 1.3) without underlying endocrine or genetic conditions were included. Mean (SD) age was 10.1 (2.8) years, BMI SD-score 2.5 (0.6), and body fat percentage 37% (7.9). Serum fasting cortisol levels were elevated (>180 μg/L) in 49 children, normal (62–180 μg/L) in 168, and decreased (<62 μg/L) in 12. Serum fasting cortisol was not significantly correlated with gender, age, or degree of adiposity. But correlated significantly with fasting glucose (R_s = 0.193; p < 0.005), triglycerides (R_s = 0. 143; p < 0.05), fibrinogen (R_s = 0.144; p < 0.05) and leptin levels (R_s = 0.145; p < 0.05). After adjustment for serum insulin and leptin, the correlation between serum cortisol and fasting glucose remained significant.

Conclusion

Elevated morning serum cortisol levels were found in 20% of overweight or obese children and adolescents, irrespective of the degree of adiposity, and were associated with higher fasting glucose, irrespective of underlying insulin resistance. The long-term cardiometabolic consequences of hypercortisolemia in childhood obesity needs further study.

Cortisol concentration affects fat and muscle mass among Polish children aged 6-13 years

Background

Cortisol is a steroid hormone acting as a stress hormone, which is crucial in regulating homeostasis. Previous studies have linked cortisol concentration to body mass and body composition.

Methods

The investigations were carried out in 2016–2017. A total of 176 children aged 6–13 years in primary schools in central Poland were investigated. Three types of measurements were performed: anthropometric (body weight and height, waist and hip circumferences), body composition (fat mass FM (%), muscle mass – MM (%), body cellular mass - BCM (%), total body water - TBW (%)), and cortisol concentration using saliva of the investigated individuals. Information about standard of living, type of feeding after birth, parental education and maternal trauma during pregnancy was obtained with questionnaires.

Results

The results of regression models after removing the environmental factors (parental education, standard of living, type of feeding after birth, and maternal trauma during pregnancy) indicate a statistically significant association between the cortisol concentration and fat mass and muscle mass. The cortisol concentration was negatively associated with FM (%) (Beta=-0.171; p = 0.026), explaining 2.32 % of the fat mass variability and positively associated with MM (%) (Beta = 0.192; p = 0.012) explaining 3.09 % of the muscle mass variability.

Conclusions

Cortisol concentration affects fat and muscle mass among Polish children.

Trial registration

The Ethical Commission at the University of Lodz (nr 19/KBBN-UŁ/II/2016).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02837-3.

Associations between second to fourth digit ratio, cortisol, vitamin D, and body composition among Polish children

Associations between body characteristics (body composition: fat mass, muscle mass, cell, and water mass as well as body proportion—BMI), the 2D:4D digit ratio, and the concentrations of cortisol and vitamin (25-OH)D among Polish children have not been studied before. A total of 133 (73 girls and 60 boys) healthy Polish children aged 7–11 years were examined. The investigation was divided into three parts: measuring (the length of the second and fourth fingers in both hands, body composition, and body height and mass), questionnaires (socioeconomic status), and laboratory investigations (25-OH vitamin D and cortisol concentrations in saliva measured with ELISA methods). Boys with digit ratios below 1 had lower vitamin D concentration than those with digit ratios equal to or higher than 1 (Z = − 2.33; p = 0.019). Only boys with the male-typical pattern of 2D:4D digit ratio tended to have a lower 25-OH vitamin D concentration in saliva. Thus, it might indicate an effect of prenatal programming on the concentrations of steroid hormones in later life. Neither vitamin D, 2D:4D digit ratio nor the cortisol level was associated with the body components or proportions. More studies are needed to evaluate the molecular and genetic background of this phenomenon.

Do stressed children have a lot on their plates? A cross-sectional study of long-term stress and diet among Finnish preschoolers

We examined the association between hair cortisol concentration (HCC) - an indicator of long-term stress - and diet among preschoolers in a cross-sectional design. The participants were 597 Finnish 3-6-year-olds, and the data were collected in 2015-16. We used 4-cm hair samples to analyze HCC during the past four months. Food consumption was assessed using a food frequency questionnaire, and we used consumption frequencies of selected food groups as well as data-driven dietary pattern scores in the analyses. The parents of the participating children reported their educational level and family income. The researchers measured the children's weight and height. We examined the associations between HCC and diet using multilevel linear mixed models adjusted for age, gender, the highest education in the family, household relative income, and child BMI. Higher HCCs were associated with less frequent consumption of fruit and berries (B estimate -1.17, 95% CI -2.29, -0.05) and lower scores in a health-conscious dietary pattern (B estimate -0.38, 95% CI -0.61, -0,14). Higher HCCs were also associated with more frequent consumption of sugary beverages (B estimate 1.30, 95% CI 0.06, 2.54) in a model adjusted for age, gender and highest education in the family, but the association attenuated after further adjustments. Our results are parallel with previous studies that show a link between stress and unhealthy diet. In the future, longitudinal studies are needed to establish a causal relationship between stress and diet among children.

Evidence for disruption of diurnal salivary cortisol rhythm in childhood obesity: relationships with anthropometry, puberty and physical activity

Background

The aim of this study was to examine the characteristics of diurnal cortisol rhythm in childhood obesity and its relationships with anthropometry, pubertal stage and physical activity.

Methods

Thirty-five children with obesity (median age: 11.80[interquartile range 10.30, 13.30] and median BMI z-score: 3.21[interquartile range 2.69, 3.71]) and 22 children with normal weight (median age: 10.85[interquartile range 8.98, 12.13] and median BMI z-score: − 0.27[interquartile range − 0.88, 0.35]) were recruited. Saliva samples were collected at 08:00, 16:00 and 23:00 h. Cortisol concentrations at 3 time points, corresponding areas under the curve (AUCs) and diurnal cortisol slope (DCS) were compared between the two groups. Anthropometric measures and pubertal stage were evaluated, and behavioural information was obtained via questionnaires.

Results

Children with obesity displayed significantly lower cortisol_08:00 (median [interquartile range]: 5.79[3.42,7.73] vs. 8.44[5.56,9.59] nmol/L, P = 0.030) and higher cortisol_23:00 (median [interquartile range]: 1.10[0.48,1.46] vs. 0.40[0.21,0.61] nmol/L, P < 0.001) with a flatter DCS (median [interquartile range]: − 0.29[− 0.49, 0.14] vs. -0.52[− 0.63, 0.34] nmol/L/h, P = 0.006) than their normal weight counterparts. The AUC increased with pubertal development (AUC_{08:00–16:00}:P = 0.008; AUC_{08:00–23:00}: P = 0.005). Furthermore, cortisol_08:00 was inversely associated with BMI z-score (β = − 0.247, P = 0.036) and waist-to-height ratio (WHtR) (β = − 0.295, P = 0.027). Cortisol_23:00 was positively associated with BMI z-score (β = 0.490, P<0.001), WHtR (β = 0.485, P<0.001) and fat mass percentage (FM%) (β = 0.464, P<0.001). Absolute values of DCS were inversely associated with BMI z-score (β = − 0.350, P = 0.009), WHtR (β = − 0.384, P = 0.004) and FM% (β = − 0.322, P = 0.019). In multivariate analyses adjusted for pubertal stage and BMI z-score, Cortisol_08:00, AUC_{08:00–16:00} and absolute values of DCS were inversely associated with the relative time spent in moderate to vigorous intensity physical activity (P < 0.05). AUC_{16:00–23:00} was positively associated with relative non-screen sedentary time and negatively associated with sleep (P < 0.05).

Conclusions

The disorder of diurnal salivary cortisol rhythm is associated with childhood obesity, which is also influenced by puberty development and physical activity. Thus, stabilizing circadian cortisol rhythms may be an important approach for childhood obesity.

Hair Cortisol Concentrations in Overweight and Obese Children and Adolescents

INTRODUCTION

Obesity in childhood and adolescence is associated with complications that resemble those seen in hypercortisolism. Hair cortisol concentration (HCC) in children is a reliable marker of long-term endogenous cortisol concentrations. We determined HCC in overweight and obese children and adolescents, and examined the relation between HCC and other cardiometabolic parameters.

METHODS

Three hundred children and adolescents aged 4-18 years (mean age ± standard error of the mean [SEM]: 10.49 ± 0.15 years; 140 [46.7%] obese, 94 [31.3%] overweight, 66 [22%] of normal BMI; 76 males, 224 females) were studied prospectively. Blood samples for determination of hematological, biochemical, and endocrinologic parameters were obtained. Systolic (SBP) and diastolic blood pressure (DBP) was determined. Scalp hair samples were collected from the posterior vertex, and HCC was measured using an electrochemiluminescence immunoassay.

RESULTS

Obese subjects had significantly higher SBP, DBP, waist and hip circumferences, waist-to-hip ratio, waist-to-height ratio, ALT, γ-GT, triglycerides, apolipoprotein-B, insulin, and HbA1C concentrations than overweight and normal-BMI subjects. HCC did not differ significantly among the three groups of subjects (mean ± SEM: 8.74 ± 0.43 vs. 8.88 ± 0.52 vs. 9.33 ± 0.72, all p > 0.05). No significant association was noted between HCC and cardiometabolic or body composition parameters. HCC was significantly higher in prepubertal girls than prepubertal boys (9.45 ± 0.38 vs. 7.35 ± 0.39, p = 0.007).

CONCLUSION

In our study, overweight and obesity was not associated with elevated HCC. Furthermore, no association was found between HCC with cardiometabolic parameters and fat mass. Further studies are required to delineate the association between overweight/obesity and HCC.

Cortisol secretion pattern in overweight/obese and normal-weight infants: a cross-sectional study

Background The salivary circadian diurnal cortisol plays an important role in growth and development. Inappropriate levels may induce changes associated with an increased risk of obesity later in life. It is unknown if there are differences in cortisol secretion pattern between overweight/obese infants when compared with theirs peers in infancy. Thus, this study aimed to compare the salivary cortisol secretion pattern in overweight/obese and normal-weight infants. Methods Thirty-three (overweight/obese = 17 and normal weight = 16) infants between 6 and 24 months of age had saliva samples collected upon awakening (T1), 30 min after waking (T2), at 12:00 am or before the baby's meal (T3), and prior to bedtime (T4). Highly sensitive enzyme immunoassays were used for cortisol analyses. Results Salivary cortisol levels were similar between the groups: T1 (p = 0.22; 95% confidence interval [CI]: -5.65, 1.37), T2 (p = 0.24; 95% CI: -8.23, 2.17), T3 (p = 0.95; 95% CI: -3.16, 2.96), and T4 (p = 0.81; 95% CI: -1.39, 1.08); and no differences were observed between area under the curve (AUC) (p = 0.80; 95% CI: -4.58-13.66). The cortisol level reduced in T4 (95% CI: 1.35-2.96) compared to T1 (95% CI: 5.15-8.49) and T2 in the overweight/obese group (p < 0.001; 95% CI: 6.02-11.04). In the normal-weight group, the cortisol reduced in T3 (95% CI: 2.86-8.18) compared to T1 (95% CI: 5.64-12.28) and decreased until T4 (p = 0.001; 95% CI: 1.25-3.37). Conclusions The overweight/obese infant group presented a different pattern of cortisol secretion, although cortisol levels did not differ between the control group.

Diurnal cortisol and obesity in adolescents with and without Down syndrome

BACKGROUND

The prevalence of obesity in adolescents with Down syndrome (DS) far exceeds that in the general population. Cortisol, an adrenal hormone, can be obesogenic when dysregulated. However, the diurnal patterns of this hormone have not been examined among individuals with DS. Variations in adiposity may also mediate cortisol regulation. This study sought to examine diurnal cortisol patterns in adolescents with DS as well as associations between cortisol function and obesity.

METHOD

A total of 32 adolescents, including 16 with DS and 16 controls with typical development (TD) of similar sex, age and Tanner pubertal stage (P > 0.05), participated in this preliminary study. Participants completed a dual-energy X-ray absorptiometry scan to measure body composition and collected saliva samples for cortisol measurements in the morning, afternoon and night. Linear mixed models with random intercepts and repeated measures were used to examine the daily trajectory of log-transformed cortisol concentrations between adolescents with and without DS. A second model examined the interaction between DS and presence of elevated body fatness.

RESULTS

Adolescents with DS had higher morning cortisol concentrations (intercept = 0.37 μg/dL), but this was not significantly different than in TD (0.35 μg/dL, P = 0.16). Cortisol significantly declined across hours (b = -0.026 μg/dL/h, P < 0.001), but this decline also did not differ from that observed in TD (b = -0.024 μg/dL/h, P = 0.43). While cortisol levels were slightly higher among adolescents with elevated body fatness, this difference was not statistically significant (P > 0.05; d = 0.30).

CONCLUSIONS

This study is the first to examine diurnal cortisol in DS but is limited in sample size. These preliminary findings suggest that diurnal cortisol patterns are not significantly different between adolescents with DS and TD and that cortisol levels are not associated with adiposity in this population. Despite these non-significant differences, youth with DS continue to be an 'at-risk' population for paediatric obesity in need of clinical intervention.

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

Background/Objectives

Associations between overweight and altered stress biology have been reported cross-sectionally during childhood, but it is unclear whether overweight precedes altered stress biology or if altered stress biology predicts greater likelihood of overweight over time. The current longitudinal study investigates associations between overweight/obesity, salivary alpha amylase and cortisol morning intercept, diurnal slope, and reactivity to social stress in a cohort of low-income children during preschool and middle childhood.

Subjects/Methods

Children were recruited through Head Start and were observed and followed into middle childhood (N = 257; M = 8.0 years). Height and weight were measured at both time points. Saliva samples were collected across the day and in response to a social challenge at both ages for alpha amylase and cortisol determination.

Results

Cross-lagged panel analyses indicated that overweight/obesity at preschool predicted lower morning alpha amylase (β = −0.18, 95% CI: −0.34, −0.03; p = .023), lower morning cortisol (β = −0.22, 95% CI: −0.38, −0.06; p = .006), lower sAA diurnal slope (β = −0.18, 95% CI: −0.34, −0.03; p = .021), and lower cortisol stress reactivity (β = −0.19, 95% CI: −0.35, −0.02; p = .031) in middle childhood. Lower alpha amylase reactivity at preschool was the only biological factor that predicted higher likelihood of overweight/obesity at middle childhood (β = −0.20, 95% CI: −0.38, −0.01; p = .035).

Conclusions

These findings suggest that overweight/obesity may be driving changes in stress biology across early to middle childhood, particularly in down-regulation of morning levels of stress hormones, diurnal sAA slope, and cortisol reactivity to stress, rather than stress biology driving overweight/obesity.

Gelatinolytic activity in gingival crevicular fluid and saliva of growing patients with Marfan syndrome: a case-control study

Background

Aim of the study was to evaluate the gelatinolytic activity in the saliva and gingival crevicular fluid from a sample group of subjects with Marfan syndrome.

Methods

Two groups were analyzed in this case-control study. A group of 28 subjects with Marfan syndrome (MG) was recruited from the Centre for Rare Disease, Marfan Clinic of Tor Vergata University Hospital. The second sample, 23 subjects, with the same characteristics and without any syndrome, was the control group (CG). Saliva and gingival crevicular fluid were collected and transferred to a sterile test tube and stored frozen at − 20 °C until analysis at the Medical Chemistry Laboratory. Gelatin substrate zymography was used for the evaluation and characterization of saliva and crevicular fluid proteinases. Correlation test and Student’s t-test have been used to analyze data.

Results

In all samples different gelatin-degrading activities were observed. Two bands, which are related to the molecular weights of pro-MMP-9 and active MMP-9, respectively, were detectable in 100% of Marfan and control samples. MMP-2 activity was higher in Marfan group. Additional bands (55/48 kDa), corresponding to the activated forms of collagenase (MMP-13), were observed in saliva samples of both groups.

Conclusions

The association of an enhanced activity by MMP-13 with an increased amount of active MMP-9 might be an important biomarker for the diagnosis of Marfan syndrome.

Longitudinal Associations of Sleep Duration, Morning and Evening Cortisol, and BMI During Childhood

OBJECTIVE

This study aimed to examine associations between sleep duration, BMI, and cortisol levels across childhood.

METHODS

Participants included 361 children adopted domestically in the United States. Random-intercept cross-lagged panel models tested for between-person and bidirectional within-person associations of sleep duration, BMI, and morning and evening cortisol at age 4.5 to 9 years.

RESULTS

Sleep duration and BMI were stable during childhood, inversely associated at the between-person level, and unrelated to morning or evening cortisol. BMI at age 6 years predicted longer sleep duration and lower evening cortisol at age 7 years, and lower morning cortisol at age 7 years predicted higher BMI at age 9 years within individuals.

CONCLUSIONS

The association between sleep and BMI is more likely a stable between-person phenomenon rather than a unidirectional association that develops within individuals over time.

The Influence of Psychological Stress, Depressive Symptoms, and Cortisol on Body Mass and Central Adiposity in 10- to-12-Year-Old Children

PURPOSE

The purpose of this study was to examine the influence of psychological stress and depressive symptoms on body mass and central adiposity in 10-to-12-year-old children and to determine the mediating role of cortisol in the relationships among psychological stress, depressive symptoms, body mass, or central adiposity.

DESIGN AND METHODS

The convenience sample included 147 children (84 females; 63 males) who were recruited from one middle school and three elementary schools in a rural area of a southeastern state. Height, weight, waist circumference (WC), and salivary cortisol were measured. Children completed the Rating Scale for Pubertal Development for screening, Children's Depression Inventory, and the Feel Bad Scale. Bivariate correlation, multiple regression analyses, and univariate regression techniques were used in data analyses.

RESULTS

A positive relationship between psychological stress and depressive symptoms (r = 0.559, p < .001) was found. Depressive symptoms explained a significant amount of the variance in body mass index (BMI) (β = 0.37, p ≤.001) and central adiposity (β = 0.40, p ≤ .001) when sex, race/ethnicity, puberty, and socioeconomic status were controlled. No statistically significant relationships were found between psychological stress and cortisol or between depressive symptoms and cortisol.

CONCLUSIONS

Depressive symptoms were reported by normoweight, overweight, and obese children. Depressive symptoms accounted for variance in body mass and central adiposity. Practice Implications In addition to regular screening of BMI and WC, nurses and other health care professionals need to consider psychological factors that contribute to childhood obesity.

Diurnal Cortisol Concentrations and Growth Indexes of 12- to 48-Month-Old Children From Mexico City

CONTEXT

Early life cortisol plays an important role in bone, muscle, and fat mobilization processes, which could influence body composition, affecting anthropometric indicators such as weight and height.

OBJECTIVE

To explore the association between diurnal cortisol levels and growth indexes in children from 12 to 48 months of age.

DESIGN

This study includes data from 404 children from the Programming Research in Obesity, Growth, Environment and Social Stressors Mexican birth cohort. Cortisol was measured in eight saliva samples collected at four time points during the day (from wakeup to bedtime), over 2 days, when the child was either 12, 18, or 24 months old. Total daytime cortisol levels were calculated by averaging the area under the curve (AUC) for the 2 days. Height and weight were measured from 12 to 48 months of age. Growth indexes were constructed according to z scores following World Health Organization standards: weight-for-age z score (Z-WFA), height/length-for-age z score, weight-for-height/length z score (Z-WFH), and body mass index-for-age z score (Z-BMIFA). Mixed models were used to analyze the association between cortisol AUC quartiles and growth indexes.

RESULTS

Cortisol showed an inverted U-shaped association with the four growth indexes. Compared with the first quartile, all quartiles had a positive association with indexes that include weight, with the second quartile having the strongest association, resulting in an average change of β (95% CI) 0.38 (0.13-0.64) for Z-WFA, 0.36 (0.10-0.62) for Z-WFH, and 0.43 (0.17-0.69) for Z-BMIFA.

CONCLUSIONS

Results suggest that early life daytime cortisol levels, as a reflection of hypothalamic-pituitary-adrenal axis development, might influence growth in early infancy.

Pathways of Association from Stress to Obesity in Early Childhood

OBJECTIVE

The objective of this study is to critically review the literature on early life stress in relation to obesity in humans, including the multiple biological and behavioral mechanisms through which early life stress exposure (birth to the age of 5 years) may associate with obesity risk during childhood.

METHODS

A review of the literature was conducted to identify studies on associations between early childhood stress and risk for obesity and the mechanisms of association. Multiple databases (PubMed, PsycInfo, Google Scholar) were used in the search as well as a "snowball" search strategy. All study designs were included.

RESULTS

Early life stress and adverse childhood experiences are associated with obesity and overweight in adults. Evidence is less consistent in children. Studies vary in the nature of the stress examined (e.g., chronic vs. acute), sample characteristics, and study designs. Longitudinal studies are needed, as the effects of early life stress exposure may not emerge until later in the life-span. Early life stress exposure is associated with biological and behavioral pathways that may increase risk for childhood obesity.

CONCLUSIONS

There is evidence that early life stress is associated with multiple biological and behavioral pathways in children that may increase risk for later obesity. Little work has detailed the interconnections among these mechanisms across development or identified potential moderators of the association. Mapping the mechanisms connecting early life stress exposure to obesity risk in young children longitudinally should be a priority for obesity researchers. Recommendations for developmentally sensitive approaches to research that can inform obesity prevention strategies are presented.

Parenting matters: Moderation of biological and community risk for obesity

Contributions of parental limit setting, negativity, scaffolding, warmth, and responsiveness to Body Mass Index (BMI) were examined. Parenting behaviors were observed in parent-child interactions, and child BMI was assessed at 5 years of age. Mothers provided demographic information and obtained child saliva samples used to derive cortisol concentration indicators (N = 250). Geospatial crime indices were computed based on publically available information for a subsample residing within the boundaries of a Pacific Northwest city (N = 114). Maternal warmth and limit setting moderated the association between child HPA-axis regulation and BMI. BMI was higher for children at lower cortisol concentrations with greater maternal warmth and lower for youngsters with mid-range cortisol values under high maternal limit setting. Maternal scaffolding moderated the effects of crime exposure, so that lower scaffolding translated into higher child BMI with greater neighborhood crime exposure. These parenting behaviors could be leveraged in obesity prevention/intervention efforts.

Is There an Association Between Cortisol and Hypertension in Overweight or Obese Children?

OBJECTIVE

The precise mechanisms behind the development of hypertension in overweight or obese children are not yet completely understood. Alterations in hypothalamic-pituitary-adrenal axis activity may play a role. We aimed to investigate the association between cortisol parameters and hypertension in overweight or obese children.

METHODS

Random urine (n=180) and early-morning saliva samples (n=126) for assessment of cortisol and cortisone were collected from 1) hypertensive overweight children (n=50), 2) normotensive overweight children (n=145), and 3) normotensive non-overweight children (n=75).

RESULTS

The age of participants was 10.4±3.3 years and 53% were boys. The urinary cortisol-to-cortisone ratio [β 1.11, 95% confidence interval (CI) 1.05-1.19] as well as urinary cortisol/creatinine (β 1.38, 95% CI 1.09-1.54), and cortisone/creatinine ratios (β 1.26, 95% CI 1.17-1.36) were significantly higher in overweight or obese than in non-overweight children. After adjusting for body mass index-standard deviation score and urinary cortisone/creatinine ratio, but not cortisol/creatinine ratio, was significantly associated with presence of hypertension (β 1.12, 95% CI 1.02-1.23). Salivary cortisol and cortisone levels were significantly lower in overweight or obese than in non-overweight children (β -4.67, 95% CI -8.19- -1.15, and β 0.89, 95% CI 0.80-0.97 respectively). There were no significant differences in cortisol parameters between hypertensive and normotensive overweight or obese children.

CONCLUSION

This study provided further evidence for an increased cortisol production rate with decreased renal 11β-hydroxysteroid dehydrogenase 2 activity and flattening of early-morning peak cortisol and cortisone in overweight or obese children. However, there were no significant differences in cortisol parameters between hypertensive and normotensive overweight and obese children.

Is HPA axis reactivity in childhood gender-specific? A systematic review

BACKGROUND

In adults, hypothalamus-pituitary-adrenal (HPA) axis activity shows sexual dimorphism, and this is thought to be a mechanism underlying sex-specific disease incidence. Evidence is scarce on whether these sex differences are also present in childhood. In a meta-analysis, we recently found that basal (non-stimulated) cortisol in saliva and free cortisol in 24-h urine follow sex-specific patterns. We explored whether these findings could be extended with sex differences in HPA axis reactivity.

METHODS

From inception to January 2016, PubMed and EMBASE.com were searched for studies that assessed HPA axis reactivity in healthy girls and boys aged ≤18 years. Articles were systematically assessed and reported in the categories: (1) diurnal rhythm, (2) cortisol awakening response (CAR), (3) protocolled social stress tests similar or equal to the Trier Social Stress Test for children (TSST-C), (4) pharmacological (ACTH and CRH) stress tests, and (5) miscellaneous stress tests.

RESULTS

Two independent assessors selected 109 out of 6158 records for full-text screening, of which 81 studies (with a total of 14,591 subjects) were included. Studies showed that girls had a tendency towards a more variable diurnal rhythm (12 out of 29 studies), a higher CAR (8 out of 18 studies), and a stronger cortisol response to social stress tests (9 out of 21 studies). We found no evidence for sex differences in cortisol response after a pharmacological challenge or to miscellaneous stress tests.

DISCUSSION

Sex differences in HPA axis reactivity appear to be present in childhood, although evidence is not unequivocal. For a better evaluation of sex differences in HPA axis reactivity, standardization of protocols and reports of stress tests is warranted.

Associations between stress biology indicators and overweight across toddlerhood

Biological stress responses are proposed as a pathway through which stress exposure can "get under the skin" and lead to health problems, specifically obesity. Yet, it is not clear when such associations may emerge or whether they are bidirectional. Cortisol and salivary alpha amylase (sAA) were considered indicators of the biological stress response. We tested the longitudinal association between cortisol and sAA and weight in 215 low-income children at ages 21, 27, and 33 months (52% male; 46% non-Hispanic white). sAA and cortisol intercept and slope (representing morning level and rate of change across the day) were calculated for each age point using random effect models. Children were weighed and length measured and categorized as overweight versus normal weight (overweight defined as weight-for-length z-score ≥85th percentile for age and sex). Cross-lagged models stratified by sex and controlling for birthweight z-score tested the concurrent and cross-lagged associations between each of 4 indices of stress biology individually (cortisol and sAA intercept and slope) and overweight. Overweight status was correlated across time. Cortisol and sAA were correlated across occasions of measurement, though somewhat less strongly in boys. There were no concurrent associations between stress indicators and overweight. sAA at 27 months predicted greater risk of overweight at 33 months in girls, such that both lower sAA intercept and more rapidly increasing sAA at 27 months predicted greater risk of overweight at 33 months (β=-0.64, p<0.05 and β=1.09, p<0.05, respectively). For boys only, overweight at 21 months predicted lower sAA intercept at 27 months (β=-0.35, p<0.05). Findings suggest that longitudinal associations of stress biology and weight status may be present only on a limited basis very early in the lifespan.

Increased Cortisol and Cortisone Levels in Overweight Children

BACKGROUND It has been unclear whether relatively high cortisol and cortisone levels are related to overweight in childhood, parental body mass index (BMI), and family dietary habits. The aim of this study was to compare cortisol and cortisone levels in urine and saliva from overweight and normal children, as well as correlations between children's BMI, parental BMI and family dietary behavior questionnaire score (QS). MATERIAL AND METHODS We analyzed the data from 52 overweight children and 53 age- and sex-matched normal-weight children aged 4-5 years. The concentrations of salivary cortisol (SF), salivary cortisone (SE), urinary cortisol (UF) and urinary cortisone (UE) were measured using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The family dietary behavior QS was answered by the parent mainly responsible for the family diet. RESULTS Average cortisol and cortisone levels were significantly higher in overweight children. There was no significant difference in the ratio of cortisol to cortisone (Rcc) and the marker of 11b-hydroxysteroid dehydrogenase type 2 (11β-HSD2) activities. The results displayed correlations among cortisol, cortisone, and Rcc. Positive correlations were weak-to-moderate between BMI and SF, SE, UF, and UE. There were correlations between BMI and maternal BMI (mBMI), and BMI was significantly associated with QS. CONCLUSIONS Our results suggest that cortisol and cortisone levels are associated with overweight in children, but the 11β-HSD2 activities showed no significant differences. Unhealthy family diet was associated with higher BMI, UF, and UE, and families with maternal overweight or obesity had a higher prevalence of children's overweight or obesity.

Gender-specific differences in hypothalamus-pituitary-adrenal axis activity during childhood: a systematic review and meta-analysis

BACKGROUND

Gender-specific differences in hypothalamus-pituitary-adrenal (HPA) axis activity have been postulated to emerge during puberty. We conducted a systematic review and meta-analysis to test the hypothesis that gender-specific differences in HPA axis activity are already present in childhood.

METHODS

From inception to January 2016, PubMed and EMBASE.com were searched for studies that assessed non-stimulated cortisol in serum or saliva or cortisol in 24-h urine in healthy males and females aged ≤18 years. Studies that conform with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement were reported. Standardized mean differences (95% CIs) were calculated and analyzed using fixed-effect meta-analysis stratified for age: <8 years (prepubertal) and 8-18 years (peri-/postpubertal). For comparison, we ran the same analyses using random-effects models.

RESULTS

Two independent assessors selected 413 out of 6158 records (7%) for full-text screening, of which 79 articles were included. Of these, 58 (with data on 16,551 subjects) were included in the meta-analysis. Gender differences in cortisol metabolism differed per age group. Boys aged <8 years had 0.18 (0.06; 0.30) nmol/L higher serum and 0.21 (0.05; 0.37) nmol/L higher salivary cortisol levels, while between 8 and 18 years, boys had 0.34 (0.28; 0.40) nmol/L lower serum and 0.42 (0.38; 0.47) nmol/L lower salivary cortisol levels. In 24-h urine, cortisol was consistently higher in boys, being 0.34 (0.05; 0.64) and 0.32 (0.17; 0.47) μg/24 h higher in the <8- and 8-18-year groups, respectively. However, gender-differences in serum cortisol <8 years and between 8 and 18 years were absent when using random-effects models.

CONCLUSIONS

Gender differences in cortisol metabolism are already present in childhood, with higher salivary cortisol in boys aged <8 years compared to girls. This pattern was reversed after the age of 8 years. In contrast, the gender-specific difference in cortisol production as assessed through 24-h urine did not change with age. Although differences were small, and analyses of gender differences in serum cortisol were inconclusive, they might contribute to gender-specific origins of health and disease.

Stress-Related and Circadian Secretion and Target Tissue Actions of Glucocorticoids: Impact on Health

Living organisms are highly complex systems that must maintain a dynamic equilibrium or homeostasis that requires energy to be sustained. Stress is a state in which several extrinsic or intrinsic disturbing stimuli, the stressors, threaten, or are perceived as threatening, homeostasis. To achieve homeostasis against the stressors, organisms have developed a highly sophisticated system, the stress system, which provides neuroendocrine adaptive responses, to restore homeostasis. These responses must be appropriate in terms of size and/or duration; otherwise, they may sustain life but be associated with detrimental effects on numerous physiologic functions of the organism, leading to a state of disease-causing disturbed homeostasis or cacostasis. In addition to facing a broad spectrum of external and/or internal stressors, organisms are subject to recurring environmental changes associated with the rotation of the planet around itself and its revolution around the sun. To adjust their homeostasis and to synchronize their activities to day/night cycles, organisms have developed an evolutionarily conserved biologic system, the "clock" system, which influences several physiologic functions in a circadian fashion. Accumulating evidence suggests that the stress system is intimately related to the circadian clock system, with dysfunction of the former resulting in dysregulation of the latter and vice versa. In this review, we describe the functional components of the two systems, we discuss their multilevel interactions, and we present how excessive or prolonged activity of the stress system affects the circadian rhythm of glucocorticoid secretion and target tissue effects.

Association between Hair Cortisol Concentration and Adiposity Measures among Children and Parents from the "Healthy Start" Study

Background

Previous studies have suggested a direct association between hair cortisol concentration (HCC) and Body Mass Index (BMI), as well as other adiposity measures. However, these studies have mostly been conducted among adult populations.

Objective

To examine the association between HCC and different measures of adiposity among a selected group of children predisposed to obesity and their parents.

Methods

We conducted a cross-sectional study based on 363 children and their parents (301 mothers and 231 fathers) participating in the “Healthy Start” study. Linear regression analysis was used to investigate associations between HCC and adiposity measures while taking into account possible confounding factors. Analyses were performed examining the association between HCC and BMI, fat mass and fat free mass index Z-scores, as well as waist circumference and waist-hip ratio among the children. Likewise, the association between HCC and BMI among the parents was explored. Finally, we examined the association between parental HCC and children’s adiposity measures.

Results

HCC was directly associated with a higher BMI among the fathers (0.49 kg/m² [95% CI: 0.09, 0.90, P = 0.02] per 100 pg/mg) and the mothers (0.93 kg/m² [95% CI: 0.24, 1.61, P = 0.01] per 100 pg/mg). We found no clear evidence of an association between HCC and adiposity measures among children. However, a high maternal HCC was associated with a high fat mass index and low fat free mass index z-score in the offspring (0.14 SD [95% CI: 0.02, 0.26, P = 0.02] and -0.17 SD [95% CI: -0.30, -0.05, P = 0.01] per 100 pg/mg, respectively).

Conclusions

Our study found no evidence of an association between HCC and measures of adiposity among children predisposed to obesity. However, HCC may be directly associated with BMI among men and women, and maternal HCC may be related to a higher fat mass and a lower fat free mass among their children.

Glucocorticoids and Metabolic Control

In response to stress, the central nervous system initiates a signaling cascade, which leads to the production of glucocorticoids (GCs). GCs act through the glucocorticoid receptor (GR) to coordinate the appropriate cellular response with the primary goal of mobilizing the storage forms of carbon precursors to generate a continuous glucose supply for the brain. Although GCs are critical for maintaining energy homeostasis, excessive GC stimulation leads to a number of undesirable side effects, including hyperglycemia, insulin resistance, fatty liver, obesity, and muscle wasting leading to severe metabolic dysfunction. Summarized below are the diverse metabolic roles of glucocorticoids in energy homeostasis and dysregulation, focusing specifically on glucose, lipid, and protein metabolism.

Glucocorticoid Receptor Mediates the Effect of High-Fat Diet on Mitochondrial Oxidative Phosphorylation in Mouse Liver

Obesity is associated with hepatic mitochondrial dysfunction. The relationship between glucocorticoids (GCs) and obesity has also been demonstrated in several researches. Recent research showed that GCs can affect the mitochondrial function. However, the role of glucocorticoid receptor (GR) in obesity-induced mitochondrial dysfunction remains unclear. C57BL/6 male mice fed with a high-fat diet (HFD) for 7 weeks were used as a model. The mice were shown to be overweight, together with lower serum and hepatic corticosterone levels. The hepatic expressions of mitochondrial DNA (mtDNA)-encoded genes were lower in the HFD mice, same as the mtDNA copy number, ATP content, and COX enzyme activity. Both the translocation of GR (NR3C1) into mitochondria and the binding of GR to the mtDNA were lower in the liver of HFD mice. The PGC1α mRNA expression, protein content, and translocation into mitochondria were also found to be reduced, with the lower GR binding to the promoter region of PGC1α in the liver of HFD mice. GR, as a transcription factor, may take an important role in the regulation of mitochondrial oxidative phosphorylation in the HFD mice by interacting with PGC1α and controlling mtDNA expression.

Nurse-Led School-Based Child Obesity Prevention

School-based childhood obesity prevention programs have grown in response to reductions in child physical activity (PA), increased sedentariness, poor diet, and soaring child obesity rates. Multiple systematic reviews indicate school-based obesity prevention/treatment interventions are effective, yet few studies have examined the school nurse role in obesity interventions. Building on a previous study, this study examines a refined health messaging (Let’s Go 5-2-1-0) program delivered to fourth and fifth graders ( n = 72) by a school nurse with reinforcement on-site health coaching by senior nursing students. Two nursing schools and two elementary schools participated. Measures of PA, body mass index percentile, and self-reported health habits were collected at baseline (School A, September 2009 and School B, January 2010) and end of year (April 2010 for both schools). Findings included statistically significant increases in PA levels and improvements in child-reported health habits. School nurses can influence obesity prevention. Further research on adoption of school nurse–led obesity interventions is warranted.

Adrenal Clocks and the Role of Adrenal Hormones in the Regulation of Circadian Physiology

The mammalian circadian timing system consists of a master pacemaker in the suprachiasmatic nucleus (SCN) and subordinate clocks that disseminate time information to various central and peripheral tissues. While the function of the SCN in circadian rhythm regulation has been extensively studied, we still have limited understanding of how peripheral tissue clock function contributes to the regulation of physiological processes. The adrenal gland plays a special role in this context as adrenal hormones show strong circadian secretion rhythms affecting downstream physiological processes. At the same time, they have been shown to affect clock gene expression in various other tissues, thus mediating systemic entrainment to external zeitgebers and promoting internal circadian alignment. In this review, we discuss the function of circadian clocks in the adrenal gland, how they are reset by the SCN and may further relay time-of-day information to other tissues. Focusing on glucocorticoids, we conclude by outlining the impact of adrenal rhythm disruption on neuropsychiatric, metabolic, immune, and malignant disorders.

Relationships between 24-hour urinary free cortisol concentrations and metabolic syndrome in obese children

CONTEXT

Clinical features of Metabolic Syndrome (MetS) and Cushing's Syndrome are similar, suggesting a pathogenetic role of hypothalamus-pituitary-adrenal axis in MetS.

OBJECTIVE

The aim of the study was to determine whether MetS diagnosis and specific clusters of MetS components (waist circumference, dyslipidemia, hypertension, and impaired glucose metabolism) are associated with serum cortisol (SC) or 24-h urinary free cortisol (UFC) levels.

DESIGN AND SETTING

We conducted cross-sectional analyses of data from our obesity cohort. We studied 264 obese children (age, 11.0 ± 2.8 years; male, 48%; BMI, 28.2 ± 5.4 kg/m(2)). We examined UFC, SC, homeostasis model assessment (HOMA), and features of MetS (waist circumference, blood pressure, fasting lipids, and glucose).

RESULTS

Slightly increased UFC concentrations were measured in 30.7% of the children. Obese children with MetS had significantly (P = .003) higher UFC levels compared with obese children without MetS. Girls demonstrated significantly higher UFC concentrations compared with boys independent of pubertal stage. UFC and SC levels were significantly related to features of MetS, but the associations were stronger for UFC. In multivariate analyses adjusted for age, sex, and body mass index, none of the features of MetS but HOMA index was correlated with UFC, whereas SC demonstrated no significant association to any parameter of MetS or HOMA.

CONCLUSIONS

Our findings support the hypothesis that changes in the hypothalamus-pituitary-adrenal axis are related to MetS in obesity. UFC seems to be a suitable marker for this relationship. Norm values for UFC adapted to obese children may help to avoid unnecessary dexamethasone suppression tests.