Genetically predicted gene expression of prefrontal DRD4 gene and the differential susceptibility to childhood emotional eating in response to positive environment.

Genetic differential susceptibility states that individuals may vary both by exhibiting poor responses when exposed to adverse environments, and disproportionally benefiting from positive settings. The dopamine D4 receptor gene (DRD4) may be particularly implicated in these effects, including disturbed eating behaviors that might lead to obesity. Here, we explore differential susceptibility to positive environments according to the predicted genetically regulated gene expression of prefrontal cortex DRD4 gene. Using MAVAN as the discovery cohort (Maternal Adversity, Vulnerability and Neurodevelopment) and GUSTO as the replication cohort (Growing Up in Singapore Towards Healthy Outcomes), we analyzed the interaction between a) a Positive postnatal environmental score, that accounts for positive outcomes in the postnatal period and b) the genetically regulated gene expression of prefrontal DRD4, computed using a machine learning prediction method (PrediXcan). The outcome measures were the pro-intake domains (Emotional over-eating, Food Responsiveness, Food Enjoyment and Desire to Drink) from the Child Eating Behavior Questionnaire at 48 months of age (MAVAN) and 60 months of age (GUSTO). The interaction between the positive environment and the predicted prefrontal DRD4 gene expression was significant for emotional over-eating in MAVAN (ß = -0.403, p < 0.02), in which the high gene expression group had more or less emotional eating according to the exposure to lower or higher positive environment respectively, showing evidence of differential susceptibility criteria. In the replication cohort, a similar result was found with the pro-intake domain Desire to drink (ß = -0.583, p < 0.05). These results provide further evidence for the genetic differential susceptibility, accounting for the benefit of positive environments.

Does social capital moderate the association between children's emotional overeating and parental stress? A cross-sectional study of the stress-buffering hypothesis in a sample of mother-child dyads.

Parental stress has been shown associated with children's eating behaviors. The stress-buffering hypothesis suggests that social resources, i.e., resources accessed via one's social networks, may prevent or attenuate the impact of stress on health. Prior research on the stress-buffering hypothesis has found evidence for the protective effects of social support (emotional, instrumental, or informational resources available in a person's life); less is known about social capital (resources available through one's social networks) as a stress buffer. Further, these studies have often examined the association between a person's direct access to social resources and their health; less research has examined whether the benefits of social resources may extend two degrees from parents to their children. Using data from a community-based birth cohort of mother-child dyads, this study examined whether mother's social capital moderated the association between maternal stress and children's emotional overeating (EO). Mothers completed health questionnaires on an annual basis and a one-time social network questionnaire in 2011-2012. EO was measured using the Children's Eating Behavior Questionnaire. Maternal stress was measured using the 18-item Parental Stress Scale. Social capital was measured using a position generator and based on the number of occupations to which a mother had access. Poisson regression analysis was used. Results showed that mother's social capital moderated the positive association between greater maternal stress and children's EO, such that maternal stress was associated with children's EO in only those mothers with low social capital. This study suggests that social capital may disrupt the transmission of maternal stress from parent to child, thereby playing a potential role in the production and reproduction of health inequalities.

Attachment and eating: A meta-analytic review of the relevance of attachment for unhealthy and healthy eating behaviors in the general population.

Attachment relationships play an important role in people's wellbeing and affliction with physical and mental illnesses, including eating disorders. Seven reviews from the clinical field have consistently shown that higher attachment insecurity-failure to form trusting and reliable relationships with others-systematically characterized individuals with eating disorders. Nevertheless, to date, it is unclear whether (and if so how) these findings apply to the population at large. Consequently, the objective of the present meta-analysis is to quantify the relationship between attachment and unhealthy and healthy eating in the general population. Data from 70 studies and 19,470 participants were converted into r effect sizes and analysed. Results showed that higher attachment insecurity (r = 0.266), anxiety (r = 0.271), avoidance (r = 0.119), and fearfulness (r = 0.184) was significantly associated with more unhealthy eating behaviors, ps = 0.000; conversely, higher attachment security correlated with lower unhealthy eating behaviors (r = -0.184, p = 0.000). This relationship did not vary across type of unhealthy eating behavior (i.e., binge eating, bulimic symptoms, dieting, emotional eating, and unhealthy food consumption). The little exploratory evidence concerning healthy eating and attachment was inconclusive with one exception-healthy eating was associated with lower attachment avoidance (r = -0.211, p = 0.000). Our results extend previous meta-analytic findings to show that lack of trusting and reliable relationships does not only set apart eating disordered individuals from controls, but also characterizes unhealthy eating behaviors in the general population. More evidence is needed to determine how attachment and healthy eating are linked and assess potential mechanisms influencing the attachment-eating relationship.

Genetic Differential Susceptibility to Socioeconomic Status and Childhood Obesogenic Behavior: Why Targeted Prevention May Be the Best Societal Investment.

IMPORTANCE: Genes may work by modulating the way individuals respond to environmental variation, and these discrete and differential genes vs environmental interactions may not be readily captured in simple association studies. OBJECTIVE: To determine whether children carrying the 7-repeat allele of the DRD4 gene living under adverse economic conditions have worse-than-average fat intake compared with those living in a healthy environment. DESIGN, SETTING, AND PARTICIPANTS: Data from an established prospective birth cohort (Maternal Adversity, Vulnerability, and Neurodevelopment) were used to study 4-year-old children from Montreal, Quebec, Canada and Hamilton, Ontario, Canada. A total of 190 children (94 girls and 96 boys) had height and weight measured and complete food diaries and were therefore eligible for the study. The study is derived from a birth cohort started in June 2003 and still ongoing. The last age of follow-up was at 6 years. EXPOSURES: Social environment was characterized based on the gross family income, and DNA was genotyped for the 7-repeat allele of the DRD4 gene. MAIN OUTCOMES AND MEASURES: Fat intake. RESULTS: The 5 steps to distinguish the differential susceptibility from other types of interaction were followed, and the study confirms that differential susceptibility is a relevant model to address the association between the 7-repeat allele of DRD4 and food choices in girls. Of the 190 children, 112 did not have the DRD4 7-repeat allele and 78 did. Baseline characteristics did not differ in these 2 groups. Although not different in several confounders, such as maternal educational level, maternal smoking during gestation, birth weight, and breastfeeding duration, girls carrying the 7-repeat allele of the DRD4 gene and living in adverse socioeconomic conditions have increased fat intake compared with girls who are noncarriers (DRD4 7+ mean, 33.95% of calories derived from fat; 95% CI, 28.76%-39.13%; DRD4 7- mean, 28.76%; 95% CI, 26.77%-30.83%). However, girls carrying the 7-repeat allele of the same gene and living in better socioeconomic conditions have decreased fat intake compared with noncarriers (DRD4 7+ mean, 29.03% of calories derived from fat; 95% CI, 26.69%-31.51%; DRD4 7- mean, 31.88%; 95% CI, 30.28%-33.58%). CONCLUSIONS AND RELEVANCE: Alleles previously considered to be obesity risk alleles might in fact function as plasticity alleles, determining openness to environmental modification and/or intervention, as seen in the girls in this study. This finding has important implications for obesity prevention and social pediatrics.

Association between the seven-repeat allele of the dopamine-4 receptor gene (DRD4) and spontaneous food intake in pre-school children.

BACKGROUND: Studies in adults show associations between the hypofunctional seven-repeat allele (7R) of the dopamine-4 receptor gene (DRD4), increased eating behaviour and/or obesity, particularly in females. We examined whether 7R is associated with total caloric intake and/or food choices in pre-schoolers. METHODS: 150 four-year-old children taking part in a birth cohort study in Canada were administered a snack test meal in a laboratory setting. Mothers also filled out a food frequency questionnaire to address childrens' habitual food consumption. Total caloric and individual macronutrient intakes during the snack meal and specific types of foods as reported in the food diaries were compared across 7R allele carriers vs. non-carriers, using current BMI as a co-variate. RESULTS: We found significant sex by genotype interactions for fat and protein intake during the snack test. Post hoc testing revealed that in girls, but not boys, 7R carriers ate more fat and protein than did non-carriers. Based on the food diaries, across both sexes, 7R carriers consumed more portions of ice cream and less vegetables, eggs, nuts and whole bread, suggesting a less healthy pattern of habitual food consumption. CONCLUSION: The 7R allele of DRD4 influences macronutrient intakes and specific food choices as early as four years of age. The specific pattern of results further suggests that prior associations between the 7R allele and adult overeating/obesity may originate in food choices observable in the preschool years. Longitudinal follow-up of these children will help establish the relevance of these findings for obesity risk and prevention.

Global health diplomacy for obesity prevention: lessons from tobacco control.

To date the global health diplomacy agenda has focused primarily on infectious diseases. Policymakers have not dedicated the same level of attention to chronic diseases, despite their rising contribution to the global burden of disease. Negotiation of the Framework convention on tobacco control provides an apt example from global health diplomacy to tackle diet-related chronic diseases. What lessons can be learned from this experience for preventing obesity? This article looks at why a global policy response is necessary, at the actors and interests involved in the negotiations, and at the forum for diplomacy.

Interactive effects of reward sensitivity and residential fast-food restaurant exposure on fast-food consumption.

BACKGROUND: Local fast-food environments have been increasingly linked to obesity and related outcomes. Individuals who are more sensitive to reward-related cues might be more responsive to such environments. OBJECTIVE: This study aimed to assess the moderating role of sensitivity to reward on the relation between residential fast-food restaurant exposure and fast-food consumption. DESIGN: Four hundred fifteen individuals (49.6% men; mean age: 34.7 y) were sampled from 7 Montreal census tracts stratified by socioeconomic status and French/English language. The frequency of fast-food restaurant visits in the previous week was self-reported. Sensitivity to reward was self-reported by using the Behavioral Activation System (BAS) scale. Fast-food restaurant exposure within 500 m of the participants' residence was determined by using a Geographic Information System. Main and interactive effects of the BAS and fast-food restaurant exposure on fast-food consumption were tested with logistic regression models that accounted for clustering of observations and participants' age, sex, education, and household income. RESULTS: Regression results showed a significant interaction between BAS and fast-food restaurant exposure (P < 0.001). Analysis of BAS tertiles indicated that the association between neighborhood fast-food restaurant exposure and consumption was positive for the highest tertile (odds ratio: 1.49; 95% CI: 1.20, 1.84; P < 0.001) but null for the intermediate (odds ratio: 1.03; 95% CI: 0.80, 1.34; P = 0.81) and lowest (odds ratio: 0.84; 95% CI: 0.51, 1.37; P = 0.49) tertiles. CONCLUSION: Reward-sensitive individuals may be more responsive to unhealthful cues in their immediate environment.

Exploring women's psychoneuroendocrine responses to cancer threat: insights from a computer-based guided imagery task.

It is proposed that computers could be used to examine patients' subjective experience in the face of cancer threat. This study provides initial validation of a computer-based stress task by examining the psychological, autonomic, and endocrine aspects of an individual's subjective experience of cancer threat surrounding mammography screening. A repeated measures design was used. A total of 38 healthy women performed a stress task (pertaining to mammography) and a control task (pertaining to osteoporosis prevention) on separate days during which psychological, autonomic, and endocrine reactions were monitored. Compared with the control task, the stress task induced higher autonomic responses (skin conductance and heart rate variability) and endocrine responses (salivary cortisol) but not psychological distress. Further, both the autonomic (skin conductance) and endocrine responses to cancer threat were moderated by mastery, a trait known to have a stress-buffering effect. Yet such a moderating effect was not observed for psychological indices of stress--that is, mood. Implications for nursing research and interventions are discussed.