Stress, Obesity, and the Metabolic Syndrome: Soul and Metabolism

Adolescents' Depressive Symptom Experience Mediates the Impact of Long-Term Exposure to Maternal Depression Symptoms on Adolescents' Body Mass Index

BACKGROUND

Obesity is a cardiovascular disease risk factor and affects approximately 13.7 million U.S. children and adolescents between the ages 2 and 19 years old in 2015-2016.

PURPOSE

To determine the relationship between children's average long-term exposure to maternal depressive symptoms age 1 month to Grade 6 and adolescents' body mass index (BMI) z-score at age 15 mediated by the adolescents' depressive symptom experience.

METHODS

A total of 1,364 infants and their families from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Study of Early Child Care and Youth Development were recruited.

RESULTS

Mediation analyses revealed a significant relationship between children's average long-term exposure to maternal depressive symptoms from age 1 month to Grade 6 and adolescents' BMI z-score at age 15 (total effect = 0.015, p = .013, 95% confidence interval (CI): 0.0032, 0.027). The adolescents' experience of depressive symptoms significantly mediated this relationship (indirect effect = 0.0021, bias-corrected bootstrapped 95% CI: 0.0004, 0.0044), with this mediated relationship more pronounced in girls.

CONCLUSIONS

Findings indicate the possible existence of a mediating role of adolescents' depressive symptoms experience in the pathway from average long-term exposure to maternal depressive symptoms during children's early life to adolescents' elevated BMI.

Personality and psychopathology differences between bariatric surgery candidates, subjects with obesity not seeking surgery management, and healthy subjects

PURPOSE

To explore personological and psychopathological characteristics in individuals with obesity presenting for bariatric surgery compared with individuals with obesity not seeking bariatric surgery and healthy individuals to help clinician decision for surgical treatment.

METHODS

379 participants [160 candidates for bariatric surgery (B) vs 219 not seeking bariatric surgery (NB)] and 304 healthy subjects (HS) were assessed with a battery of well-validated psychometric tests.

RESULTS

The B group showed an intermediate personality profile between HS and NB. They also exhibited lower depressive and anxiety scores. Eating and attachment impairment were found lower in the B group with respect to the NB.

CONCLUSIONS

Candidates for bariatric surgery display advantageous personality features and lower rates in psychopathology compared to other participants with obesity. These features may represent both traits facilitating the search for a bariatric treatment, and the preferred ones selected by the surgeon. Implications for clinicians addressing obese participants towards bariatric surgery and limitations concerning "impression management" are discussed.

LEVEL OF EVIDENCE

Level III, case-control analytic study.

Yoga for Risk Reduction of Metabolic Syndrome: Patient-Reported Outcomes from a Randomized Controlled Pilot Study

Lifestyle change is recommended as treatment for adults at risk for metabolic syndrome (MetS), although adoption of new behavioral patterns is limited. In addition, most existing lifestyle interventions do not address psychological stress or quality of life, both of which impact the burden of MetS. Yoga, a form of physical activity that incorporates psychological components (e.g., maintaining attention, relaxation), is a promising intervention for improving the burden of MetS. This randomized controlled trial assessed the feasibility and preliminary efficacy of a 12-week yoga program coupled with an evidence-based health education program (HED) compared to HED alone. A secondary, exploratory aim examined perceived stress, quality of life, and related psychological outcomes (mindfulness, perceived health competence, and mood). Sixty-seven adults at risk for MetS enrolled (mean age [SD]: 58 [10] years; 50% male; 79% non-Hispanic White). Preliminary results revealed significantly larger improvements in two quality of life domains (role-physical and general health perceptions) in the HED plus yoga group versus HED alone (ps < 0.05). This is the first study that implemented lifestyle education along with yoga to evaluate the potential unique effects of yoga on participants at risk for MetS. A larger clinical trial is warranted to further investigate these promising patient-reported outcomes.

Stress, the stress system and the role of glucocorticoids

All living organisms have developed a highly conserved and regulatory system, the stress system, to cope with a broad spectrum of stressful stimuli that threaten, or are perceived as threatening, their dynamic equilibrium or homeostasis. This neuroendocrine system consists of the hypothalamic-pituitary-adrenal (HPA) axis and the locus caeruleus/norepinephrine-autonomic nervous system. In parallel with the evolution of the homeostasis and stress concepts from ancient Greek to modern medicine, significant advances in the field of neuroendocrinology have identified the physiologic biochemical effector molecules of the stress response. Glucocorticoids, the end-products of the HPA axis, play a fundamental role in the maintenance of both resting and stress-related homeostasis and, undoubtedly, influence the physiologic adaptive reaction of the organism against stressors. If the stress response is dysregulated in terms of magnitude and/or duration, homeostasis is turned into cacostasis with adverse effects on many vital physiologic functions, such as growth, development, metabolism, circulation, reproduction, immune response, cognition and behavior. A strong and/or long-lasting stressor may precipitate and/or cause many acute and chronic diseases. Moreover, stressors during pre-natal, post-natal or pubertal life may have a critical impact on our expressed genome. This review describes the central and peripheral components of the stress system, provides a comprehensive overview of the stress response, and discusses the role of glucocorticoids in a broad spectrum of stress-related diseases. © 2014 S. Karger AG, Basel.

Gender difference in interactions between MAOA promoter uVNTR polymorphism and negative familial stressors on body mass index among Chinese adolescents

OBJECTIVES

Monoamine oxidase A (MAOA) modulates metabolism of serotonin and dopamine metabolism, neurotransmitters involved in regulation of appetite and food intake. The gene coding for MAOA contains a 30-bp tandem repeat (uVNTR) polymorphism in its promoter region that has been previously identified to be associated with obesity with mixed findings in the literature. Our goals were to replicate the population effects of this functional polymorphism on obesity risk, and to further explore gender differences and interaction effects with negative stressors.

METHODS

Analyses were conducted with data on genotypes, measured weight and height, and self-reported behavioural characteristics among 1101 Chinese adolescents 11-15 years old living in Wuhan, China.

RESULTS

Girls with the high-activity allele had significantly lower body mass index (BMI; β = -0.25 ± 0.98, P = 0.011) compared to those with the low activity allele. Experience of negative familial stressors (e.g., death or illness of family members, hit or scolded by parents and increased quarrelling with parents, parents argued frequently) significantly weakened this protective genetic effect on BMI (P for interaction = 0.043). Stratified analyses showed a significant protective genetic effect on BMI only within the stratum of low stress level (β = -0.44 ± 0.14, P = 0.002). No similar effect was observed among boys.

CONCLUSIONS

Our findings confirm the genetic effects of MAOA uVNTR polymorphism on BMI in a Chinese adolescent population and suggest potential genetic interactions with negative familial stressors.

Attachment security and obesity in US preschool-aged children

OBJECTIVE

To estimate the association between attachment security in children aged 24 months and their risk for obesity at 4½ years of age. Insecure attachment is associated with unhealthy physiologic and behavioral responses to stress, which could lead to development of obesity.

DESIGN

Cohort study.

SETTING

National sample of US children born in 2001.

PARTICIPANTS

Children and mothers participating in the 2003 and 2005-2006 waves of the Early Childhood Longitudinal Study, Birth Cohort, conducted by the National Center for Education Statistics. Our analytic sample included 6650 children (76.0% of children assessed in both waves).

MAIN EXPOSURE

Attachment security at 24 months was assessed by trained interviewers during observation in the child's home. Insecure attachment was defined as lowest quartile of attachment security, based on the security score from the Toddler Attachment Sort-45 Item.

OUTCOME MEASURE

Obesity at 4½ years of age (sex-specific body mass index ≥95th percentile for age).

RESULTS

The prevalence of obesity was 23.1% in children with insecure attachment and 16.6% in those with secure attachment. For children with insecure attachment, the odds of obesity were 1.30 (95% confidence interval, 1.05-1.62) times higher than for children with secure attachment after controlling for the quality of mother-child interaction during play, parenting practices related to obesity, maternal body mass index, and sociodemographic characteristics.

CONCLUSIONS

Insecure attachment in early childhood may be a risk factor for obesity. Interventions to increase children's attachment security should examine the effects on children's weight.

Chronic stress and obesity in adolescents: scientific evidence and methodological issues for epidemiological research

AIMS

This review describes the role of chronic stress in the development of obesity and available methodologies for the assessment of chronic stress in humans, in particular adolescents, with the aim of developing a feasible methodology to implement in an epidemiological study.

DATA SYNTHESIS

Chronic stress seems to be associated with the aetiology of obesity by interacting with both mechanisms of energy intake (increase of appetite and energy intake) and expenditure (decrease of physical activity) and by stimulating visceral fat accumulation in favour of abdominal obesity. However, more research is necessary to unravel the underlying mechanisms of the obesity-inducing effects of chronic stress, especially in adolescents. In addition to experimental research, epidemiological observational studies, in particular cohort studies, are appropriate given their non-intervening character, lower budgetary costs and natural setting. In practice, stress can be assessed by means of either a subjective approach using stressor checklists or interviews, or an objective approach measuring biomarkers of stress. In epidemiological research in adolescents, a combination of both strategies is recommended, with a preference for a general stressor checklist for adolescents and measurement of salivary cortisol, one of the most used and well-characterized biomarkers of stress.

CONCLUSION

This review provides basic evidence for the positive association between chronic stress and obesity, but also points out the need for more research in adolescents to further elucidate the role of chronic stress in the aetiology of obesity in this crucial life period. Good, well-standardized epidemiological surveys could be of great benefit in this research area.

Fatty acids and postprandial inflammation

PURPOSE OF REVIEW

Postprandial inflammation is an independent factor in evaluating food quality in addition to the well known parameters of nutritional value, caloric content and amount of carbohydrates, fats, proteins, minerals and vitamins. Among the latter, the quality and quantity of fatty acids in a meal is a major determinant of the magnitude of postprandial inflammation. Purpose of this review is to describe this exciting new area of research and its repercussions in the way we, the consumers, and the food industry evaluate the type and quantity of fat in food.

RECENT FINDINGS

A number of, by now classical, epidemiologic studies have documented a strong association between the type of fatty acids consumed and the incidence of cardiovascular diseases. Recently published reports suggest that the adverse effect of dietary fatty acids on cardiovascular health depends on their postprandial modification of innate immunity ending in the so-called 'postprandial metabolic inflammation'.

SUMMARY

The quantity of fat and its qualitative characteristics such as the percentage of saturated fatty acids and the ratio of n-3 to n-6 polyunsaturated fatty acids (PUFAs) in a meal have emerged as major determinants of the magnitude of postprandial inflammatory response. In this review, we will summarize all experimental evidence suggesting that the two families of PUFA appear to have antagonistic effects on postprandial inflammation, n-3 PUFA being anti-inflammatory while n-6 PUFA proinflammatory.

Restorative yoga in adults with metabolic syndrome: a randomized, controlled pilot trial

BACKGROUND

Metabolic syndrome increases the risk of diabetes and cardiovascular disease. Yoga improves some metabolic parameters, but it has not been studied in persons with metabolic syndrome. We conducted a randomized controlled pilot trial to determine whether a restorative yoga intervention was feasible and acceptable in underactive, overweight adults with metabolic syndrome.

METHODS

Twenty six underactive, overweight adult men and women with metabolic syndrome were randomized to attend 15 yoga sessions of 90 minutes each over 10 weeks or to a wait-list control group. Feasibility was measured by recruitment rates, subject retention, and adherence. Acceptability was assessed by interview and questionnaires. Changes in metabolic outcomes and questionnaire measures from baseline to week 10 were calculated.

RESULTS

A total of 280 people were screened by phone, and 93 with high likelihood of metabolic syndrome were invited to a screening visit. Of the 68 who attended screening visits, 26 (38%) were randomized, and 24 (92%) completed the trial. Attendance at yoga classes and adherence to home practice exceeded our goals. In the yoga group, all participants gave the study the highest possible satisfaction rating, and the majority (87%) felt that the yoga poses were easy to perform. There was trend to reduced blood pressure (p = 0.07), a significant increase in energy level (p < 0.009), and trends to improvement in well-being (p < 0.12) and stress (p < 0.22) in the yoga versus control group.

CONCLUSIONS

Restorative yoga was a feasible and acceptable intervention in overweight adults with metabolic syndrome. The efficacy of yoga for improving metabolic parameters in this population should be explored in a larger randomized controlled trial.

Mitochondria as key components of the stress response

The exquisitely orchestrated adaptive response to stressors that challenge the homeostasis of the cell and organism involves important changes in mitochondrial function. A complex signaling network enables mitochondria to sense internal milieu or environmental changes and to adjust their bioenergetic, thermogenic, oxidative and/or apoptotic responses accordingly, aiming at re-establishment of homeostasis. Mitochondrial dysfunction is increasingly recognized as a key component in both acute and chronic allostatic states, although the extent of its role in the pathogenesis of such conditions remains controversial. Genetic and environmental factors that determine mitochondrial function might contribute to the significant variation of the stress response. Understanding the often reciprocal interplay between stress mediators and mitochondrial function is likely to help identify potential therapeutic targets for many stress and mitochondria-related pathologies.