The relationship between executive function, AD/HD, overeating, and obesity

Functional activity of the caudate mediates the relation between early childhood microstructural variations and elevated metabolic syndrome scores

BACKGROUND

Metabolic syndrome score in children assesses the risk of developing cardiovascular disease in future. We aim to probe the role of the caudate in relation to the metabolic syndrome score. Furthermore, using both functional and structural neuroimaging, we aim to examine the interplay between functional and structural measures.

METHODS

A longitudinal birth cohort study with functional and structural neuroimaging data obtained at 4.5, 6.0 and 7.5 years and metabolic syndrome scores at 8.0 years was used. Pearson correlation and linear regression was used to test for correlation fractional anisotropy (FA) and fractional amplitude of low frequency fluctuations (fALFF) of the caudate with metabolic syndrome scores. Mediation analysis was used to test if later brain measures mediated the relation between earlier brain measures and metabolic syndrome scores. Inhibitory control was also tested as a mediator of the relation between caudate brain measures and metabolic syndrome scores.

RESULTS

FA at 4.5 years and fALFF at 7.5 years of the left caudate was significantly correlated with metabolic syndrome scores. Post-hoc mediation analysis showed that fALFF at 7.5 years fully mediated the relation between FA at 4.5 years and metabolic syndrome scores. Inhibitory control was significantly correlated with fALFF at 7.5 years, but did not mediate the relation between fALFF at 7.5 years and metabolic syndrome scores.

CONCLUSIONS

We found that variations in caudate microstructure at 4.5 years predict later variation in functional activity at 7.5 years. This later variation in functional activity fully mediates the relation between microstructural changes in early childhood and metabolic syndrome scores at 8.0 years.

The Mediation Role of Health Behaviors in the Association between Self-Regulation and Weight Status among Preschool Children: A Sex-Specific Analysis

Previous studies have supported the link between children’s self-regulation (CSR) and weight status, but the potential pathways have not been elucidated yet. We aimed to investigate whether and to what extent health behaviors mediate this association, as well as to explore the sex effect. For this study, we recruited 3740 preschoolers in Wuhan, China. The height and weight of children were measured, and a body mass index of the ≥85th percentile was defined as overweight/obesity (OWO). We used the Children’s Behavior Questionnaire, with measured domains including inhibitory control, impulsivity, anger, and attentional focusing, to assess CSR. The primary caregivers’ SR (PSR) was assessed with the Self-Control Scale. Information on lifestyles collected from questionnaires was utilized to construct the health behavior index (HBI). We found that Children’s HBI was associated with both CSR and PSR, inhibitory control (OR = 0.81, p < 0.001), anger (OR = 1.23, p < 0.001), attentional focusing (OR = 0.70, p < 0.001), impulsivity (OR = 1.23, p < 0.001), and PSR (OR = 0.73, p < 0.001). Children’s impulsivity was associated with their OWO (OR = 1.11, p = 0.013) which was partly mediated by the HBI (direct effect: β = 0.092, p = 0.026; indirect effect: β = 0.011, p = 0.007). The sex-specific analysis indicated that this mediation effect was only significant in boys. These results indicated that impulsivity is associated with childhood weight status, which is partially mediated by health behaviors, especially in boys.

Advertising Influences Food Choices of University Students With ADHD

Objective: Previous research in adults with ADHD showed high rates of obesity and unhealthy food choices. There is evidence that contextual cues, for example, advertisements, influence food choices. This study assessed the sensitivity of university students with ADHD to advertised food. Method: University students (N = 457) with and without ADHD participated in a cafeteria field experiment. Food choices were examined in periods of advertising either healthy or unhealthy sandwiches. Results: Students with ADHD (a) chose less healthy food items, (b) were more influenced by advertising, (c) showed the same overall healthy food choices as controls when exposed to healthy advertising. Conclusion: Students with ADHD chose unhealthier foods at the cafeteria but were also more influenced by advertising. Healthy food advertisements raised their healthy food choices. As this population has strong association with unhealthy dietary patterns, it is important to investigate the influence of food cues on their eating habits.

Obesity and ADHD: Exploring the role of body composition, BMI polygenic risk score, and reward system genes

The association between obesity and attention-deficit hyperactivity disorder (ADHD) has been extensively reported in the literature. However, the potential mechanisms underlying this association are not completely understood. This study aimed to evaluate the association between body composition and ADHD and explore the possible genetic mechanisms involved. We used data from the 1982 Pelotas (Brazil) Birth Cohort at age 30-year follow-up (N = 3630). We first used logistic regression analysis to test whether body mass index (BMI), fat mass (FM), and fat-free mass (FFM) were associated with ADHD. We further tested the association between BMI polygenic risk score (BMI-PRS) and ADHD and the role of the genes upregulated in the reward system using a gene-set association approach. BMI (odds ratio [OR] = 1.05; 95% confidence interval [CI], 1.00-1.09; p = 0.038) and FM (OR = 1.04; 95% CI, 1.00-1.07; p = 0.043) were associated with ADHD. The BMI-PRS was associated with ADHD (using p-value threshold (P_T) = 0.4; OR = 1.65; 95% CI, 1.02-2.65) at a nominal level. In gene-set analysis, the reward system genes were associated with BMI in subjects with a high BMI-PRS score, considering P_T = 0.4 (p = 0.014). The results suggest that BMI genetic components, especially those genes related to the reward system, may be involved in this association.

The relation between symptoms of ADHD and symptoms of eating disorders in university students

There is evidence to suggest an association between Attention-Deficit/Hyperactivity Disorder (ADHD) and eating disorders (EDs). As those with subclinical symptoms of ADHD or ED often experience impairment, this cross-sectional study examined the relationship between ADHD symptoms and ED symptoms in a predominately subclinical undergraduate population. Students (n = 133; 80% female) completed questionnaires measuring ADHD and ED symptomatology. The relation between overall ADHD symptoms and ED symptoms was examined using linear regression; findings indicated that higher ADHD symptoms significantly predicted higher ED symptoms. When symptoms of both disorders were further delineated, inattentive ADHD symptoms consistently predicted higher ED symptoms (bulimia, body dissatisfaction, and drive for thinness). A number of mechanisms may explain the association between ADHD and ED symptoms, including shared executive function deficits, poor emotion regulation, and mood challenges. These mechanisms may have clinical relevance in ADHD and ED treatment and prevention efforts.

Eating behaviors, depression, and anxiety levels of pre bariatric surgery patients with obesity comorbid with or without Attention deficit and hyperactivity disorder: ADHD or Major Depression? Which is more related with eating behaviors?

OBJECTIVE

A high rate of attention deficit and hyperactivity disorder (ADHD) has been reported in patients undergoing obesity treatment. It is controversial whether ADHD solely or its comorbid disorders account for eating behaviors associated with obesity.

METHODS

After presurgery psychiatric assessment, 100 severely obese patients (50 with ADHD and 50 without ADHD) were administered Adult Attention Deficit Hyperactivity Disorder Self-Report Scale(ASRS), Wender Utah Rating Scale(WURS), Three-Factor Eating Questionnaire(TFEQ), and Beck Depression Inventory(BDI) and Beck Anxiety Inventory(BAI).

RESULTS

Patients with obesity and ADHD had significantly greater emotional eating, susceptibility to hunger, depression, and anxiety but less restraint of eating scores than those without ADHD. Disinhibition of eating scores and presence of Binge Eating Disorder(BED) did not differ significantly between ADHD and non-ADHD groups. Obese patients with major depression had significantly higher ASRS, WURS, TFEQ, BAI scores, disinhibition of eating control, emotional eating, susceptibility to hunger, and diagnosis of BED than nondepressed ones.

CONCLUSIONS

Major depression and anxiety disorder have associations with disinhibition of eating control, emotional eating, susceptibility to hunger and BED, ADHD. Disinhibition of eating and BED did not differ according to the presence of ADHD; thus, depression was associated with eating control on more constructs than ADHD in our study.

A Behavioral Genetic Model of the Mechanisms Underlying the Link Between Obesity and Symptoms of ADHD

Objective: The ADHD-obesity link has been suggested to result from a shared underlying basis of suboptimal dopamine (DA); however, this theory conflicts evidence that an amplified DA signal increases the risk for overeating and weight gain. A model was tested in which ADHD symptoms, predicted by hypodopaminergic functioning in the prefrontal cortex, in combination with an enhanced appetitive drive, predict hedonic eating and, in turn, higher body mass index (BMI). Method: DRD2 and DRD4 markers were genotyped. The model was tested using structural equation modeling in a nonclinical sample (N = 421 adults). Results: The model was a good fit to the data. Controlling for education, all parameter estimates were significant, except for the DRD4-ADHD symptom pathway. The significant indirect effect indicates that overeating mediated the ADHD symptoms-BMI association. Conclusion: Results support the hypothesis that overeating and elevated DA in the ventral striatum-representative of a greater reward response-contribute to the ADHD symptom-obesity relationship.

The role of emotion regulation in childhood obesity: implications for prevention and treatment

Stress and negative emotions pose a major threat to public health, by increasing the risk of obesity. Since the management process for emotions (emotion regulation; ER) is developed in childhood, we present a novel conceptual framework model for the role of ER in the prevention and treatment of childhood obesity. A narrative review of the literature by electronic database search (MEDLINE, Web of Knowledge and Scopus) was conducted of observational and interventional/experimental literature on ER and obesity and the underlying concepts. We also present an overview of ER intervention techniques. Our model indicates that childhood ER is a link between stress and obesity. Stress along with ineffective ER leads to abnormal cortisol patterns, emotional eating, sedentary lifestyle, reduction of physical activity, and sleep problems. Simultaneously, a healthy lifestyle could show benefits on ER and in developing adaptive ER strategies. In the development of obesity and ER, parents also play a role. By contrast, effective ER skills decrease obesity-related unhealthy behaviour and enhance protective factors, which boost health. The literature contains some observational studies of children but very few intervention studies, most of which are pilot or on-going studies. In conclusion, encouraging effective ER could be a useful new approach for combating and treating childhood obesity. Future ER intervention studies are needed to confirm the validity of this model in children.

Is there an association between eating behaviour and attention-deficit/hyperactivity disorder symptoms in preschool children?

BACKGROUND

There is some evidence that aberrant eating behaviours and obesity co-occur with attention-deficit/hyperactivity disorder (ADHD) symptoms. The present study is the first that aims to investigate the association between eating behaviours and ADHD symptoms in early childhood in a population-based cohort.

METHODS

We included 471 preschool children from the Rhea mother-child cohort in Crete, Greece. Parents completed the Children's Eating Behaviour Questionnaire to assess children's eating behaviour and the 36-item ADHD test (ADHDT) to evaluate ADHD symptoms at 4 years of age. Multivariable linear regression models were used to examine the association of eating behaviours with ADHD symptoms.

RESULTS

Regarding children's food approach eating behaviours, we observed a positive association between food responsiveness and total ADHD index, as well as impulsivity, inattention and hyperactivity subscale, separately. Similarly, there was a significant positive association between emotional overeating and ADHD symptoms. With regard to children's food avoidant behaviours, food fussiness was found to be significantly associated with the impulsivity subscale. A dose-response association between the food approach behaviours and ADHD symptoms was also observed. Children on the medium and highest tertile of the food responsiveness subscale had increased scores on the ADHD total scale, as compared to those on the lowest tertile. As regards emotional overeating, children in the highest tertile of the scale had higher scores on ADHD total and hyperactivity.

CONCLUSIONS

Our findings provide evidence that food approach eating behaviours such as food responsiveness and emotional overeating are associated with the increased ADHD symptoms in preschool children. Future studies to better understand this overlap will enhance potential interventions.

Toward a Better Understanding of the Link Between Parent and Child Physical Activity Levels: The Moderating Role of Parental Encouragement

BACKGROUND

Research on adolescent physical activity is mixed regarding the role of parent activity. This study tested parent encouragement, direct modeling, and perceived influence as moderators of objectively-measured (accelerometer) parent and child moderate-to-vigorous physical activity (MVPA) associations.

METHODS

Parent-child dyads (n = 423; mean child age = 11.33 yrs.) wore accelerometers for 7 days; parents completed surveys. Hierarchical linear regression models tested moderation using a product of constituent terms interaction.

RESULTS

Parent-reported encouragement moderated the association between parent and child MVPA (β = -.15, P = .01, ΔR2 = .02, P < .01). Among parents with lower MVPA, child MVPA was higher for children receiving high encouragement (mean = 3.06, SE = .17) vs. low (mean = 3.03, SE = .15, P = .02) and moderate encouragement (mean = 3.40, SE = .09) vs. low (P = .04).

CONCLUSIONS

Physical activity promotion programs may use parent encouragement as a tool to boost child activity, but must consider other child and parent characteristics that could attenuate effects.

Overlapping neurobehavioral circuits in ADHD, obesity, and binge eating: evidence from neuroimaging research

Attention-deficit/hyperactivity disorder (ADHD) and conditions involving excessive eating (eg, obesity, binge/loss of control eating) are increasingly prevalent within pediatric populations, and correlational and some longitudinal studies have suggested inter-relationships between these disorders. In addition, a number of common neural correlates are emerging across conditions, eg, functional abnormalities within circuits subserving reward processing and executive functioning. To explore this potential cross-condition overlap in neurobehavioral underpinnings, we selectively review relevant functional neuroimaging literature, specifically focusing on studies probing (i) reward processing, (ii) response inhibition, and (iii) emotional processing and regulation, and we outline 3 specific shared neurobehavioral circuits. Based on our review, we also identify gaps within the literature that would benefit from further research.

Executive function and food approach behavior in middle childhood

Executive function (EF) has long been considered to be a unitary, domain-general cognitive ability. However, recent research suggests differentiating “hot” affective and “cool” cognitive aspects of EF. Yet, findings regarding this two-factor construct are still inconsistent. In particular, the development of this factor structure remains unclear and data on school-aged children is lacking. Furthermore, studies linking EF and overweight or obesity suggest that EF contributes to the regulation of eating behavior. So far, however, the links between EF and eating behavior have rarely been investigated in children and non-clinical populations. First, we examined whether EF can be divided into hot and cool factors or whether they actually correspond to a unitary construct in middle childhood. Second, we examined how hot and cool EF are associated with different eating styles that put children at risk of becoming overweight during development. Hot and cool EF were assessed experimentally in a non-clinical population of 1657 elementary-school children (aged 6–11 years). The “food approach” behavior was rated mainly via parent questionnaires. Findings indicate that hot EF is distinguishable from cool EF. However, only cool EF seems to represent a coherent functional entity, whereas hot EF does not seem to be a homogenous construct. This was true for a younger and an older subgroup of children. Furthermore, different EF components were correlated with eating styles, such as responsiveness to food, desire to drink, and restrained eating in girls but not in boys. This shows that lower levels of EF are not only seen in clinical populations of obese patients but are already associated with food approach styles in a normal population of elementary school-aged girls. Although the direction of effect still has to be clarified, results point to the possibility that EF constitutes a risk factor for eating styles contributing to the development of overweight in the long-term.

Attention-deficit/hyperactivity disorder and impairment in executive functions: a barrier to weight loss in individuals with obesity?

BACKGROUND

An increasing body of research points to a significant association of obesity to Attention-Deficit/Hyperactivity Disorder (ADHD) and deficits in executive functions. There is also preliminary evidence suggesting that children with ADHD may be at risk of obesity in adulthood.

DISCUSSION

In this article, we discuss the evidence showing that ADHD and/or deficits in executive functions are a barrier to a successful weight control in individuals enrolled in weight loss programs. Impairing symptoms of ADHD or deficits in executive functions may foster dysregulated eating behaviors, such as binge eating, emotionally-induced eating or eating in the absence of hunger, which, in turn, may contribute to unsuccessful weight loss. ADHD-related behaviors or neurocognitive impairment may also hamper a regular and structured physical activity. There is initial research showing that treatment of comorbid ADHD and executive functions training significantly improve the outcome of obesity in individuals with comorbid ADHD or impairment in executive functions.

SUMMARY

Preliminary evidence suggests that comorbid ADHD and deficits in executive functions are a barrier to a successful weight loss in individuals involved in obesity treatment programs. If further methodologically sound evidence confirms this relationship, screening and effectively managing comorbid ADHD and/or executive functions deficits in individuals with obesity might have the potential to reduce not only the burden of ADHD but also the obesity epidemics.

Neurocognitive correlates of obesity and obesity-related behaviors in children and adolescents

Childhood obesity rates have risen dramatically over the past few decades. Although obesity has been linked to poorer neurocognitive functioning in adults, much less is known about this relationship in children and adolescents. Therefore, we conducted a systematic review to examine the relationship between obesity and obesity-related behaviors with neurocognitive functioning in youth. We reviewed articles from 1976 to 2013 using PsycInfo, PubMed, Medline and Google Scholar. Search terms included cognitive function, neurocognitive function/performance, executive function, impulsivity, self-regulation, effortful control, cognitive control, inhibition, delayed gratification, memory, attention, language, motor, visuo-spatial, academic achievement, obesity, overweight, body mass index, waist-hip ratio, adiposity and body fat. Articles were excluded if participants had health problems known to affect cognitive functioning, the study used imaging as the only outcome measure, they were non-peer-reviewed dissertations, theses, review papers, commentaries, or they were non-English articles. Sixty-seven studies met inclusion criteria for this review. Overall, we found data that support a negative relationship between obesity and various aspects of neurocognitive functioning, such as executive functioning, attention, visuo-spatial performance, and motor skill. The existing literature is mixed on the effects among obesity, general cognitive functioning, language, learning, memory, and academic achievement. Executive dysfunction is associated with obesity-related behaviors, such as increased intake, disinhibited eating, and less physical activity. Physical activity is positively linked with motor skill. More longitudinal research is needed to determine the directionality of such relationships, to point towards crucial intervention time periods in the development of children, and to inform effective treatment programs.

ADHD symptomatology in eating disorders: a secondary psychopathological measure of severity?

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) has commonly been described in psychiatric disorders. Although several studies have found positive associations between abnormal eating patterns during childhood and ADHD, there is a lack of studies on ADHD and Eating Disorders (ED). The aims of this exploratory study were 1) to assess the ADHD symptoms level in ED and to ascertain whether there are differences among ED subtypes; 2) to analyze whether the presence of ADHD symptoms is associated with more severe eating disorder symptoms and greater general psychopathology; and 3) to assess whether the ADHD symptoms level is associated with specific temperament and character traits.

METHODS

191 female ED patients were included. Assessment was carried out with the EDI-2, ASRS-v1.1, the SCL-90-R and the TCI-R.

RESULTS

The ADHD symptoms level was similar in bulimia, eating disorder not otherwise specified and binge eating subtypes, and lower in anorexic patients. Obsessiveness and Hostility were significantly positively associated with ADHD symptoms. A path model showed that ADHD was associated with high Novelty Seeking and low Self-Directedness, whereas ED severity was influenced by ADHD severity and low Self-Directedness.

CONCLUSIONS

Bingeing/purging ED subtypes have a high ADHD symptoms level, also related with more severe eating, general and personality psychopathology.

Impact of serotonin (5-HT)2C receptors on executive control processes

Although the serotonin (5-hydroxytryptamine, 5-HT) neurotransmitter system has been implicated in modulating executive control processes such as attention, response inhibition, and behavioral flexibility, the contributions of particular serotonin receptors remain unclear. Here, using operant-based behavioral paradigms, we demonstrate that mice with genetically ablated 5-HT2C receptors (2CKO mice) display deficits in executive functions. 2CKO mice were impaired in the acquisition of a visuospatial attention task as assessed in the 5-choice serial reaction time task (5-CSRTT). In this task, 2CKO mice exhibited marked impairment of attentional processes, with normal response inhibition. We assessed dynamic changes in neurotransmitter levels within the nucleus accumbens (NAc) by in vivo microdialysis in task-performing animals. Extracellular dopamine concentrations were elevated in the NAc of 2CKO mice during task performance, indicating that 5-HT2C receptors impact dopamine homeostasis during a visuospatial attention task. These findings raise the possibility that disinhibition of mesolimbic dopamine pathways contributes to impaired attention and perturbed task performance in 2CKO mice. Additionally, in a spatial reversal learning task, 2CKO mice failed to improve their performance over a series of reversals, indicating that intact 5-HT2C receptor signaling is required to accurately respond to repeated changes in reward contingencies. In contrast to the 2CKO phenotype in the 5-CSRTT, wild-type mice treated with the 5-HT2C receptor antagonist SB242084 exhibited diminished response inhibition, suggesting differing effects of acute pharmacological blockade and constitutive loss of 5-HT2C receptor activity. Altogether, these findings provide insights into the serotonergic regulation of executive control processes and suggest that impaired 5-HT2C receptor signaling during development may predispose to executive function disorders.

Attention-deficit/hyperactivity disorder and adverse health outcomes

Attention-deficit/hyperactivity disorder (ADHD) is defined by extreme levels of inattention-disorganization and/or hyperactivity-impulsivity. In DSM-IV, the diagnostic criteria required impairment in social, academic, or occupational functioning. With DSM-5 publication imminent in 2013, further evaluation of impairment in ADHD is timely. This article reviews the current state of knowledge on health-related impairments of ADHD, including smoking, drug abuse, accidental injury, sleep, obesity, hypertension, diabetes, and suicidal behavior. It concludes by suggesting the need for new avenues of research on mechanisms of association and the potential for ADHD to be an early warning sign for secondary prevention of some poor health outcomes.