Personality traits and leptin

Association between endocrine and neuropsychological endophenotypes and gambling disorder severity

BACKGROUND

Neurobiological characteristics have been identified regarding the severity of gambling disorder (GD). The aims of this study were: (1) to examine, through a path analysis, whether there was a relationship between neuroendocrine features, potentially mediational GD variables, and GD severity, and (2) to associate neuroendocrine variables, with GD severity-related variables according to gambling preferences.

METHODS

The sample included 297 outpatients with GD. We analyzed endocrine concentrations of different appetite-related hormones (ghrelin, liver antimicrobial peptide 2 [LEAP-2], leptin, adiponectin), and neuropsychological performance (working memory, cognitive flexibility, inhibition, decision making, premorbid intelligence). Path analysis assessed mechanisms between neuroendocrine features and GD severity, including mediational GD variables (impulsivity traits and gambling-related cognitive distortions). Partial correlations evaluated the associations between neuroendocrine variables, including impulsivity traits, and variables related to GD severity (DSM-5, South Oaks Gambling Screen, illness duration, and gambling-related cognitive distortions).

RESULTS

Lower adiponectin concentrations predicted greater GD severity, while higher LEAP-2 concentrations predicted more gambling-related cognitive distortions. Likewise, better neuropsychological performance directly predicted GD severity, but worse neuropsychological performance was associated with GD severity through the mediational variables of impulsivity traits and gambling-related cognitive distortions. Also, in non-strategic individuals with GD, poor working memory was associated with gambling expectancies and predictive control. In strategic individuals with GD, poor cognitive flexibility was associated with illusion of control, predictive control, and inability to stop gambling.

CONCLUSIONS

These results provide updated information about the comprehension of the interaction between neuroendocrine features, clinical variables, and severity of GD. Thus, neurobiological functions seem to be strongly related to GD severity.

Correlations between personality traits, personality disorders, and immunometabolic markers

Evidence links immune system alterations to major psychiatric disorders. The few previous studies on personality traits or personality disorders (PDs) indicate that immunometabolic dysregulation may be prevalent in this population. This study aimed to investigate relationships between personality traits, PDs, and immunometabolic markers in peripheral blood. We hypothesized that neuroticism would be correlated with elevated leptin. Participants were recruited as young adults seeking care for general psychiatric disorders. They responded to a personality inventory and were assessed for PDs, and reevaluated again at a 12 years follow-up. Blood samples were collected at the follow-up and analyzed for 29 immunometabolic markers. A positive correlation was found between the personality trait neuroticism and leptin (ρ = 0.31, p = 0.02). An exploratory analysis also revealed a positive correlation between brain-derived neurotrophic factor (ρ = 0.36, p < 0.01) and neuroticism. These findings remained after adjusting for other variables in general linear models. There were no relationships between PDs and any immunometabolic markers. Results both confirm previous findings of correlations between the immunometabolic system and personality traits and suggest directions for future research.

Personality traits and the risk of urinary incontinence: Evidence from three longitudinal samples

OBJECTIVE

Urinary incontinence (UI) is a common condition with a substantial negative impact on older adults' quality of life. This study examines whether individual differences in behavioral, cognitive, and emotional traits assessed by the five major dimensions of personality are related to the risk of concurrent and incident UI.

METHODS

Participants were older women and men (N > 26,000) from the Midlife in the United States Survey, the Health and Retirement Study, and the English Longitudinal Study of Aging. In each cohort, personality traits (measured with the Midlife Development Inventory) and demographic (age, sex, education, and race), clinical (body mass index, diabetes, blood pressure), and behavioral (smoking) factors were assessed at baseline. UI was assessed at baseline and again 8-20 years later. Results for each cohort were combined in random-effect meta-analyses.

RESULTS

Consistently across cohorts, higher neuroticism and lower conscientiousness were related to a higher risk of concurrent and incident UI. To a lesser extent, extraversion, openness, and agreeableness were also related to lower risk of concurrent and incident UI. BMI, diabetes, blood pressure, and smoking partially accounted for these associations. There was little evidence that age or sex moderated the associations.

CONCLUSIONS

The present study provides novel, robust, and replicable evidence linking personality traits to UI. The higher vulnerability for UI for individuals who score higher on neuroticism and lower on conscientiousness is consistent with findings for other multifactorial geriatric syndromes. Personality traits can help identify individuals at risk and may help contextualize the clinical presentation of comorbid emotional, cognitive, and behavioral symptoms.

Whither dominance? An enduring evolutionary legacy of primate sociality

This article discusses dominance personality dimensions found in primates, particularly in the great apes, and how they compare to dominance in humans. Dominance traits are seen in virtually all primate species, and these dimensions reflect how adept an individual is at ascending within a social hierarchy. Among great apes, dominance is one of the most prominent personality factors but, in humans, dominance is usually modeled as a facet of extraversion. Social, cultural, and cognitive differences between humans and our closest ape relatives are explored, alongside humanity's hierarchical and egalitarian heritage. The basic characteristics of dominance in humans and nonhuman great apes are then described, alongside the similarities and differences between great apes. African apes live in societies each with its own hierarchical organization. Humans were a possible exception for some of our history, but more recently, hierarchies have dominated. The general characteristics of high-dominance humans, particularly those living in industrialized nations, are described. Dominance itself can be subdivided into correlated subfactors: domineering, prestige, and leadership. Various explanations have been posed for why dominance has declined in prominence within human personality factor structures, and several possibilities are evaluated. The value of dominance in personality research is discussed: dominance has links to, for instance, age, sex, aggression, self-esteem, locus of control, stress, health, and multiple socioeconomic status indicators. The piece concludes with recommendations for researchers who wish to assess dominance in personality.

Cluster analysis in gambling disorder based on sociodemographic, neuropsychological, and neuroendocrine features regulating energy homeostasis

BACKGROUND

The heterogeneity of gambling disorder (GD) has led to the identification of different subtypes, mostly including phenotypic features, with distinctive implications on the GD severity and treatment outcome. However, clustering analyses based on potential endophenotypic features, such as neuropsychological and neuroendocrine factors, are scarce so far.

AIMS

This study firstly aimed to identify empirical clusters in individuals with GD based on sociodemographic (i.e., age and sex), neuropsychological (i.e., cognitive flexibility, inhibitory control, decision making, working memory, attention, and set-shifting), and neuroendocrine factors regulating energy homeostasis (i.e., leptin, ghrelin, adiponectin, and liver-expressed antimicrobial peptide 2, LEAP-2). The second objective was to compare the profiles between clusters, considering the variables used for the clustering procedure and other different sociodemographic, clinical, and psychological features.

METHODS

297 seeking-treatment adult outpatients with GD (93.6% males, mean age of 39.58 years old) were evaluated through a semi-structured clinical interview, self-reported psychometric assessments, and a protocolized neuropsychological battery. Plasma concentrations of neuroendocrine factors were assessed in peripheral blood after an overnight fast. Agglomerative hierarchical clustering was applied using sociodemographic, neuropsychological, and neuroendocrine variables as indicators for the grouping procedure. Comparisons between the empirical groups were performed using Chi-square tests (χ2) for categorical variables, and analysis of variance (ANOVA) for quantitative measures.

RESULTS

Three-mutually-exclusive groups were obtained, being neuropsychological features those with the greatest weight in differentiating groups. The largest cluster (Cluster 1, 65.3%) was composed by younger males with strategic and online gambling preferences, scoring higher on self-reported impulsivity traits, but with a lower cognitive impairment. Cluster 2 (18.2%) and 3 (16.5%) were characterized by a significantly higher proportion of females and older patients with non-strategic gambling preferences and a worse neuropsychological performance. Particularly, Cluster 3 had the poorest neuropsychological performance, especially in cognitive flexibility, while Cluster 2 reported the poorest inhibitory control. This latter cluster was also distinguished by a poorer self-reported emotion regulation, the highest prevalence of food addiction, as well as a metabolic profile characterized by the highest mean concentrations of leptin, adiponectin, and LEAP-2.

CONCLUSIONS

To the best of our knowledge, this is the first study to identify well-differentiated GD clusters using neuropsychological and neuroendocrine features. Our findings reinforce the heterogeneous nature of the disorder and emphasize a role of potential endophenotypic features in GD subtyping. This more comprehensive characterization of GD profiles could contribute to optimize therapeutic interventions based on a medicine of precision.

Plasma concentration of leptin is related to food addiction in gambling disorder: Clinical and neuropsychological implications

Background

Data implicate overlaps in neurobiological pathways involved in appetite regulation and addictive disorders. Despite different neuroendocrine measures having been associated with both gambling disorder (GD) and food addiction (FA), how appetite-regulating hormones may relate to the co-occurrence of both entities remain incompletely understood.

Aims

To compare plasma concentrations of ghrelin, leptin, adiponectin, and liver-expressed antimicrobial peptide 2 (LEAP-2) between patients with GD, with and without FA, and to explore the association between circulating hormonal concentrations and neuropsychological and clinical features in individuals with GD and FA.

Methods

The sample included 297 patients diagnosed with GD (93.6% males). None of the patients with GD had lifetime diagnosis of an eating disorder. FA was evaluated with the Yale Food Addiction Scale 2.0. All patients were assessed through a semi-structured clinical interview and a psychometric battery including neuropsychological tasks. Blood samples to measure hormonal variables and anthropometric variables were also collected.

Results

From the total sample, FA was observed in 23 participants (FA+) (7.7% of the sample, 87% males). When compared participants with and without FA, those with FA+ presented both higher body mass index (BMI) (p < 0.001) and leptin concentrations, after adjusting for BMI (p = 0.013). In patients with FA, leptin concentrations positively correlated with impulsivity, poorer cognitive flexibility, and poorer inhibitory control. Other endocrine measures did not differ between groups.

Discussion and conclusions

The present study implicates leptin in co-occurring GD and FA. Among these patients, leptin concentration has been associated with clinical and neuropsychological features, such as impulsivity and cognitive performance in certain domains.

The use of non-invasive brain stimulation techniques to reduce body weight and food cravings: A systematic review and meta-analysis

Several studies demonstrated non-invasive brain stimulation (NIBS) techniques such as transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS) are safe and simple techniques that can reduce body weight, food cravings, and food consumption in patients with obesity. However, a systematic to evaluate the efficacy of active NIBS versus sham stimulation in reducing body weight and food cravings in patients with obesity is not available. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) using PubMed, Embase, MEDLINE, and Cochrane Central Register of Control Trial between January 1990 and February 2022. Mean differences (MDs) for continuous outcome variables with 95% confidence intervals (95% CIs) were used to examine the effects of NIBS on body weight and body mass index (BMI), whereas the hedges's g test was used to measure the effects on food craving. Nineteen RCTs involving 571 participants were included in this study. Active neurostimulation (TMS and tDCS) was significantly more likely than sham stimulation to reduce body weight (TMS: -3.29 kg, 95% CI [-5.32, -1.26]; I2  = 48%; p < .001; tDCS: -0.82 kg, 95% CI [-1.01, -0.62]; I2  = 0.0%; p = .00) and BMI (TMS: -0.74, 95% CI [-1.17, -0.31]; I2  = 0% p = .00; tDCS: MD = -0.55, 95% CI [-2.32, 1.21]; I2  = 0% p = .54) as well as food cravings (TMS: g = -0.91, 95% CI [-1.68, -0.14]; I2  = 88 p = .00; tDCS: g = -0.32, 95% CI [-0.62, -0.02]; p = .04). Compared with sham stimulation, our findings indicate that active NIBS can significantly help to reduce body weight and food cravings. Hence, these novel techniques may be used as primary or adjunct tools in treating patients with obesity.

Are Signals Regulating Energy Homeostasis Related to Neuropsychological and Clinical Features of Gambling Disorder? A Case-Control Study

Gambling disorder (GD) is a modestly prevalent and severe condition for which neurobiology is not yet fully understood. Although alterations in signals involved in energy homeostasis have been studied in substance use disorders, they have yet to be examined in detail in GD. The aims of the present study were to compare different endocrine and neuropsychological factors between individuals with GD and healthy controls (HC) and to explore endocrine interactions with neuropsychological and clinical variables. A case−control design was performed in 297 individuals with GD and 41 individuals without (healthy controls; HCs), assessed through a semi-structured clinical interview and a psychometric battery. For the evaluation of endocrine and anthropometric variables, 38 HCs were added to the 41 HCs initially evaluated. Individuals with GD presented higher fasting plasma ghrelin (p < 0.001) and lower LEAP2 and adiponectin concentrations (p < 0.001) than HCs, after adjusting for body mass index (BMI). The GD group reported higher cognitive impairment regarding cognitive flexibility and decision-making strategies, a worse psychological state, higher impulsivity levels, and a more dysfunctional personality profile. Despite failing to find significant associations between endocrine factors and either neuropsychological or clinical aspects in the GD group, some impaired cognitive dimensions (i.e., WAIS Vocabulary test and WCST Perseverative errors) and lower LEAP2 concentrations statistically predicted GD presence. The findings from the present study suggest that distinctive neuropsychological and endocrine dysfunctions may operate in individuals with GD and predict GD presence. Further exploration of endophenotypic vulnerability pathways in GD appear warranted, especially with respect to etiological and therapeutic potentials.

The relationship between Big Five Personality Traits, eating habits, physical activity, and obesity in Indonesia based on analysis of the 5th wave Indonesia Family Life Survey (2014)

This study investigated the association between Big Five Personality Traits (Openness to new experience, Conscientiousness, Extraversion, Agreeableness, Neuroticism) and nutrition-related variables (eating habits, physical activity, and obesity using Body Mass Index). We used secondary data from the Indonesia Family Life Survey (IFLS) wave 5 involving a total of 14,473 men and 16,467 women aged 15-101 years (mean = 37.34; SD = 14.916) in Indonesia that was selected by stratified random sampling conducted in the period 2014 to 2015. Data were collected through interviews with the Big Five Index 15 and a questionnaire similar to the Global Physical Activity Questionnaire which was translated into the Indonesian language, and based on measurements of height and weight. Analyses used binary logistic regression test controlled by socio-demographic factors (age, gender, education, occupation, and marital status) to determine the association between Big Five Personality Traits and eating habits (recommended and non-recommended foods), physical activity, and obesity. Results showed that openness and extraversion were positively associated with recommended and non-recommended foods, conscientiousness was positively associated with only recommended foods, agreeableness was positively associated with recommended foods, and negatively associated with only one non-recommended food. Whereas, neuroticism was positively associated with non-recommended foods and negatively associated with recommended foods. Openness (p = 0.010; OR = 1.015; 95% CI = 1.004-1.027) and conscientiousness (p < 0.001; OR = 1.045; 95% CI = 1.030-1.059) were associated with physical activity. Conscientiousness (p = 0.002; OR = 1.025; 95% CI = 1.009-1.041), extraversion (p < 0.001; OR = 1.079; 95% CI = 1.065-1.092), and neuroticism (p < 0.001; OR = 0.966; 95% CI = 0.953-0.978) were associated with obesity. Although some results were different from previous studies, these associations can be used as strategies of behavioral change due to the adaptation of personality characteristics, which can be modified even though the personality tends to be persistent. Further studies are needed to understand other mechanisms that might underlie this association.

Reduction of impulsivity in patients receiving deep transcranial magnetic stimulation treatment for obesity

PURPOSE

Aims of the present study were to investigate a wide array of psychological symptoms through validated psychometric tests, before and after 5 weeks of deep Transcranial Magnetic Stimulation (dTMS) in individuals with obesity, and to identify possible relationships with neuroendocrine parameters.

METHODS

Forty-five patients with obesity (33 F, 12 M; age 48.8 ± 9.9 years; body wt 97.6 ± 14.2 Kg; BMI 36.2 ± 4.2) were randomized into two groups: 26 received high frequency (HF) dTMS and 19 Sham stimulation for 5 weeks. At baseline and after the 5-week treatment, all patients underwent the following psychometric evaluations: Food Cravings Questionnaire-Trait (FCQ-T) and its subscales, Barratt Impulsiveness Scale-11 (BIS-11), State and Trait Anxiety Inventory (STAI-y1 and STAI-y2), and Beck Depression Inventory (BDI). Hormonal and neuroendocrine markers were assessed at the first and last dTMS session.

RESULTS

By adjusting for baseline variables and treatment arms, a significant decrease in body wt and BMI was found in HF group, both with univariate (p = 0.019) and multivariate analyses (p = 0.012). Impulsivity significantly decreased in HF group, both with univariate (p = 0.031) and multivariate analyses (p = 0.011). A positive association between the impulsivity score change and the leptin level variation (p = 0.031) was found.

CONCLUSION

The decrease of impulsivity together with the BMI reduction in individuals with obesity, treated with real stimulation, suggests that impulsivity may be a risk factor for obesity. Treatment with dTMS revealed to be effective in reducing both BMI and impulsivity by enhancing inhibitory capacity of Pre-Frontal Cortex (PFC), and modulating neuroendocrine system, especially leptin.

Alcohol use disorders and ADHD

Despite a growing literature on the complex bidirectional relationship of ADHD and substance use, reviews specifically focusing on alcohol are scarce. ADHD and AUD show a significant genetic overlap, including genes involved in gluatamatergic and catecholaminergic neurotransmission. ADHD drives risky behavior and negative experiences throughout the lifespan that subsequently enhance a genetically increased risk for Alcohol Use Disorders (AUD). Impulsive decisions and a maladaptive reward system make individuals with ADHD vulnerable for alcohol use and up to 43 % develop an AUD; in adults with AUD, ADHD occurs in about 20 %, but is vastly under-recognized and under-treated. Thus, routine screening and treatment procedures need to be implemented in AUD treatment. Long-acting stimulants or non-stimulants can be used to treat ADHD in individuals with AUD. However, it is crucial to combine medical treatment for ADHD with pharmacotherapy and psychotherapy for AUD, and other comorbid disorders. Identification of individuals at risk for AUD, especially those with ADHD and conduct disorder or oppositional defiant disorder, is a key factor to prevent negative outcomes.

Neuroticism is positively associated with leptin/adiponectin ratio, leptin and IL-6 in young adults

High neuroticism is related to cardiovascular morbidity. Early detection of metabolic and cardiovascular risk is important in high-risk groups to enable preventive measures. The aim of this study was therefore to explore if neuroticism is associated with early biomarkers for cardiovascular and metabolic disease in young adults from a psychiatry cohort. Blood samples and self-ratings on neuroticism with the Swedish universities Scales of Personality (SSP) questionnaire were collected from 172 psychiatric outpatients and 46 healthy controls. The blood samples were analysed for plasma leptin, adiponectin, CRP, IL-6 and TNF-α. Associations between neuroticism and biomarkers were assessed using Spearman's correlation coefficients and generalized linear models adjusting for confounders. In the adjusted generalized linear models, neuroticism predicted the leptin/adiponectin ratio (p = 0.003), leptin (p = 0.004) and IL-6 (p = 0.001). These associations were not better explained by current major depressive disorder and/or anxiety disorder. Adiponectin, CRP and TNF-α were not associated with neuroticism. In conclusion, the findings suggest that high neuroticism is related to elevated levels of plasma leptin/adiponectin ratio, leptin and IL-6 in young adults. Young adults with high neuroticism may therefore benefit from preventive interventions to decrease the risk for future metabolic and cardiovascular morbidity, but more research is required to test this hypothesis.

The effect of dietary approaches to stop hypertension (DASH) diet on attention-deficit hyperactivity disorder (ADHD) symptoms: a randomized controlled clinical trial

BACKGROUND

The dietary approaches to stop hypertension (DASH) diet have several components like high amounts of fruits, vegetables, low-fat dairy products, and vitamin C and low amounts of simple sugars that might improve attention-deficit hyperactivity disorder (ADHD) symptoms. We aimed to investigate the effect of a DASH diet on children (aged 6-12 years) with ADHD, for the first time.

METHODS

Participants were randomized to receive a DASH or a control diet for 12 weeks. The severity of ADHD symptoms [determined by abbreviated 10-item Conner's scale (ACS), 18-item Swanson, Nolan and Pelham (SNAP-IV) scale and strengths and difficulties questionnaire (SDQ)] were assessed every four weeks.

RESULTS

Eighty children completed the study. After adjustment for confounders, parent (- 4.71 for the DASH group vs. - 3 for the control group) and teacher-reported (- 5.35 vs. - 1.87) ACS scores, parent-, teacher-, child-reported hyperactivity (- 1.40 vs. - 0.66, - 1.95 vs. -0.63, - 1.60 vs. - 0.43, respectively), emotional symptoms (- 1.50 vs. - 0.45, - 1.42 vs. - 0.63, and - 1.09 vs. - 0.61, respectively), and total SDQ scores (- 3.81 vs. - 1.65, - 4.11 vs. - 1.23, - 4.44 vs. - 1.26, respectively), teacher-reported of conduct problems (- 1.42 vs. - 0.63), peer relationship problems (- 0.87 vs. - 0.07), and prosocial behaviors (1.36 vs. 0.08) assessed by the SDQ were significantly improved in the DASH group compared with the control group (P < 0.05).

CONCLUSION

Adherence to a DASH-style diet might improve ADHD symptoms. Further RCTs which include participants from both sexes and with longer follow-up periods are needed to warrant current findings (The trial registration code: IRCT20130223012571N6; http://irct.ir/trial/12623 ). Trial registration Trial registration number: The trial was registered in the Iranian registry of clinical trials (registration code: IRCT20130223012571N6), URL: http://irct.ir/trial/12623 .

Association between personality profile and subclinical atherosclerosis: The role of genes and environment

BACKGROUND

The mechanism underlying the association between personality profile and subclinical atherosclerosis is poorly understood. This study explores the association between personality, carotid atherosclerosis and arterial stiffness, and the contribution of genes and environment to this association.

METHODS

Early atherosclerotic traits, including carotid intima-media thickness (CCA-IMT), aortic pulse wave velocity (PWVao) and heart rate, were assessed in 318 adult twins, who also completed a Big Five personality questionnaire. Using the co-twin control approach, the association between intra-pair differences in clinical and personality scores was assessed in dizygotic (DZ) and monozygotic (MZ) twins separately.

RESULTS

An association between CCA-IMT and extroverted personality, as well as between PWVao and openness to experience was detected. The inverse association between CCA-IMT and extraversion was persistent in DZ and disappeared in MZ twins, suggesting genetic confounding. In contrast, the association between PWVao and openness to experience was of the same magnitude in DZ and MZ twins, thus surviving the adjustment for genetic and shared environmental factors.

CONCLUSIONS

This study highlights that the association between some psychological factors and cardiovascular traits may be partly explained by genetic factors. This result may provide support for the feasibility of prevention programs based on assessing familiarity for personality disorders to detect genetic risk for subclinical cardiovascular disease.

The association between leptin receptor polymorphism and suicidal behaviour in depressed adolescents

Objective: Suicide is the second leading cause of death in adolescence. Genetic studies implicate the genetic component of suicide independent from associated psychiatric disorder. Although genetics is an important factor that might be associated with suicide, limited progress is achieved to identify the candidate genes in adolescents.Methods: The study included 97 patients and 106 controls. Five leptin receptor single nucleotide polymorphism (SNP) region examined. Depressive scores were measured with Children Depression Inventory and suicidal behaviour was measured by Suicide Probability Scale. Logistic and linear regression analysis used for determining to predictors.Results: In linear regression analysis (R²: 0.786) both previous suicide attempt (B:5.553, t:2.613 p: .035) and having a mutant allele in rs1171276 SNP region (B:4.346 t:2.220 p: .048) have been associated with suicidal behaviour. In logistic regression analysis, family history of depression (p < .0001, OR: 4.2 [1.7-9.6]) and number of stressful life events (p: .001, OR: 1.7 [1.3-2.1]) predicted depression significantly.Conclusion: Leptin receptor polymorphism could result in an increase in impulsive behaviour and suicide scores with leptin resistance. Our research is the first study to investigate the relationship between depression, suicidal behaviour and leptin receptor polymorphism in adolescent sample. Similar studies could be carried out on a community basis.KEY POINTSAn association has been found between rs1171276 single nucleotide polymorphism of leptin receptor and the suicide probability scores in depressed adolescents.Family history of depression and number of stressful life events predict depressive scores significantly.Leptin receptor single nucleotide polymorphism may be a risk factor for adolescent suicide by increasing impulsive behaviour.

The association of leptin secretion with cognitive performance in patients with eating disorders

This study is an investigation of neuropsychological performance in patients with anorexia nervosa, bulimia nervosa, and binge eating disorder and hormonal secretion patterns for ghrelin, leptin, insulin, and glucose. An oral glucose tolerance test (OGTT) was performed in a cohort of n = 30 female patients suffering from eating disorders as well as n = 20 control females. All participants underwent the Wisconsin Card Sorting Test (WCST), the Trail Making Test (TMT), and a go/no-go task using food vs. neutral stimuli. Patients with anorexia nervosa differed from controls in their leptin response to the OGTT. While the four groups under investigation did not differ in neuropsychological performance, we found leptin responses to the OGTT to be associated with performance in the food-specific go/no-go task. These preliminary results may indicate a putative association between leptin concentrations and neuropsychological performance, particularly in measures of inhibitory control. Further studies investigating the role of leptin in impulsive behaviors in eating disorders would be useful.

The Effectiveness of Dietary Approaches to Stop Hypertension Diet Intervention in Persons with Arterial Hypertension and Obesity: A Key Role of the Patients' Personality Profile

BACKGROUND/AIMS

Benefits resulting from weight loss and dietary approaches to stop hypertension (DASH) diet in the treatment of arterial hypertension led to a search for a better therapy that would include psychological factors. The present study aimed to assess the relationship between the personality traits included in the Big Five personality traits and the effectiveness of treatment for weight loss in patients with essential hypertension and excessive body weight.

METHODS

The study involved 84 patients with essential hypertension, overweight or obesity, managed by a hypertensiologist. All patients underwent a 3-month diet treatment as part of the development process of an individualised eating plan that follows the principles of DASH diet and food education. Body mass index and DASH index were calculated before and after the therapy. NEO Five-Factor Inventory was applied to measure psychological variables.

RESULTS

The intervention led to a statistically significant increase of DASH index measured before and after treatment. There was a significant correlation between the increase of DASH index and gender. Patients presented higher intensity of openness to experience, extraversion, conscientiousness and lower levels of neuroticism and agreeableness compared to general population.

CONCLUSION

The influence of psychological variables on the observed difference between men and women in DASH values and weight loss was not demonstrated.

Personality and Body Weight: Mechanisms, Longitudinal Associations and Context

Models of personality and health have grown in complexity as more is discovered about how traits are related to health-related behaviors, morbidity, and mortality. The present article applies a model of personality and health that incorporates longitudinal relations, behavioral and physiological mechanisms, and context to the relation between Five-Factor Model personality traits and body mass index (BMI) and obesity (BMI≥30). Conscientiousness is associated consistently with lower body weight; the relation between the other traits and BMI is more complex. Conscientiousness is also associated with risk of obesity over time, and specific aspects of Conscientiousness and Neuroticism are associated with greater weight gain and are also sensitive to changes in weight over time. Behavioral (e.g., physical activity) and physiological (e.g., inflammation) factors explain part of the association between personality and BMI. Finally, the broader social environment shapes the expression of personality in relation to body weight. This review highlights replicable associations between personality and BMI and potential mechanisms of this association. Future research needs to better address how specific aspects of the social and family environment moderate the relation between personality and BMI and take a lifespan perspective to better incorporate how traits contribute to weight starting in childhood.

Modelling Gender Differences in the Economic and Social Influences of Obesity in Australian Young People

In Australia, as in many other developed economies, the prevalence of obesity has risen significantly in all age groups and especially in young males and females over the past decade. Using data from the Household, Income and Labour Dynamics in Australia (HILDA) Survey, this paper investigates the influence of economic, personality and social factor demographics on the incidence of obesity in Australian youths. The study uses two random parameters logit models, including one that allows for gender-specific differences in the conditioning variables. The models reveal notable differences between the most important variables affecting the incidence of obesity amongst females compared to males. These differences are notable to consider for policy and intervention programs aimed at reducing the problem of obesity.

The Obesity-Impulsivity Axis: Potential Metabolic Interventions in Chronic Psychiatric Patients

Pathological impulsivity is encountered in a broad range of psychiatric conditions and is thought to be a risk factor for aggression directed against oneself or others. Recently, a strong association was found between impulsivity and obesity which may explain the high prevalence of metabolic disorders in individuals with mental illness even in the absence of exposure to psychotropic drugs. As the overlapping neurobiology of impulsivity and obesity is being unraveled, the question asked louder and louder is whether they should be treated concomitantly. The treatment of obesity and metabolic dysregulations in chronic psychiatric patients is currently underutilized and often initiated late, making correction more difficult to achieve. Addressing obesity and metabolic dysfunction in a preventive manner may not only lower morbidity and mortality but also the excessive impulsivity, decreasing the risk for aggression. In this review, we take a look beyond psychopharmacological interventions and discuss dietary and physical therapy approaches.

Impulsivity is associated with blood pressure and waist circumference among adolescents with bipolar disorder

OBJECTIVE

Cardiovascular risk factors (CVRFs) and impulsivity are common in bipolar disorder (BD), and CVRFs are also linked with impulsivity through a number of mechanisms, both behavioral and biological. This study examines the association between CVRFs and impulsivity in adolescents with BD.

METHODS

Subjects were 34 adolescents with BD and 35 healthy control (HC) adolescents. CVRFs were based on International Diabetes Federation metabolic syndrome criteria (triglycerides, high-density lipoprotein cholesterol, waist circumference, blood pressure (BP) and glucose). Impulsivity was measured using the computerized Cambridge Gambling Task (CGT). Analyses controlled for age, IQ, lifetime attention deficit hyperactivity disorder, and current antipsychotic use.

RESULTS

Adolescents with BD had higher diastolic BP (73.36 ± 9.57 mmHg vs. 67.91 ± 8.74 mmHg, U = 401.0, p = 0.03), higher triglycerides (1.13 ± 0.60 mmol/L vs. 0.78 ± 0.38 mmol/L, U = 373.5, p = 0.008), and were more likely to meet high-risk criteria for waist circumference (17.6% vs. 2.9%, p = 0.04) vs. HC. Within the BD group, CGT sub-scores were correlated with CVRFs. For example, overall proportion bet was positively correlated with systolic (r = 0.387, p = 0.026) and diastolic (ρ = 0.404, p = 0.020) BP. Quality of decision-making was negatively correlated with systolic BP (ρ = -0.401, p = 0.021) and waist circumference (ρ = -0.534, p = 0.003). Significant interactions were observed, such that BD diagnosis moderates the relationship between both waist circumference and BP with CGT sub-scores.

CONCLUSION

BP and waist circumference are associated with impulsivity in BD adolescents, but not in HC adolescents. Future studies are warranted to determine temporality and to evaluate whether optimizing CVRFs improves impulsivity among BD adolescents.

Student Characteristics and Behaviours in Childhood Predict Self–reported Health in Middle Adulthood

We examined how self–reported and teacher–rated student characteristics in primary school were associated with adult self–reported health. A representative sample of Luxembourgish students was assessed in 1968 ( M age = 11.9, SD = 0.6) and 2008 (N = 745; M age = 51.8, SD = 0.6). Self–reported sense of inferiority and pessimism in childhood were negatively related to subjective health and vitality–related quality of life/health in adulthood (rs = −.08 to −.12); teacher–rated studiousness (age 12 years) was positively related to subjective health, healthcare utilization and vitality–related quality of life/health (age 52 years; rs = .13 to .16). After controlling for childhood IQ, parental socio–economic status, educational attainment and sex in multiple regression analyses, most effects of teacher–rated studiousness showed incremental validity beyond the controls. School entitlement, sense of inferiority, impatience and pessimism were positively related to body mass index (rs = .08 to .13). The responsible student scale and teacher–rated studiousness were negatively related to body mass index (rs = −.09 to −.13). The findings demonstrate that childhood characteristics and behaviours are important life–course predictors of key health dimensions beyond childhood IQ and parental socio–economic status. In addition, this narrower level of assessment adds significantly to the empirical body of knowledge on long–term predictors of health outcomes in adulthood. Copyright © 2016 European Association of Personality Psychology.

Are Trait–Outcome Associations Caused by Scales Or Particular Items? Example Analysis of Personality Facets and Bmi

In personality research, trait–outcome associations are often studied by correlating scale sum scores with an outcome. For example, an association between the NEO Impulsiveness scale and body mass index (BMI) is often interpreted to pertain to underlying trait Impulsiveness. We propose that this expectation can be corroborated by testing for Spearman's theorem of indifference of indicator. Namely, an underlying trait–outcome association should not depend on the specific items (i.e. indicators) used to measure the trait. To test this theorem, we outline an indicator exclusion procedure and demonstrate its viability using a simulation design. We then apply this procedure to test personality–BMI associations for indifference of indicator in a large population–based sample of adult Estonians (N = 2581) using self–ratings and informant ratings obtained with the NEO Personality Inventory–3. Our results show that the N5: Impulsiveness–BMI association mostly depends on two eating–related items, suggesting that the trait associated with BMI may be narrower than the trait the N5: Impulsiveness scale is supposed to measure. Associations between BMI, E3: Assertiveness and C2: Order seem to pertain to the trait. In sum, testing for indifference of indicator provides a potentially useful method to clarify trait–outcome relationships. R scripts are provided that implement the indicator exclusion procedure. Copyright © 2015 European Association of Personality Psychology

Personality traits and body mass index: Modifiers and mechanisms

OBJECTIVE

To identify how demographic factors (sex, age, ethnicity) modify the association between personality traits and body mass index (BMI) and to test the extent that diet and physical activity account for the personality-BMI relations.

DESIGN

Cross-sectional study with a diverse sample (N = 5150, 50% female, 19% African American, 15% Hispanic). Participants completed a measure of the five major dimensions of personality and reported on their physical activity, diet and food intake behaviour, and height and weight.

MAIN OUTCOME MEASURES

BMI and obesity (BMI ≥ 30).

RESULTS

High Neuroticism was associated with higher BMI and risk for obesity, whereas Conscientiousness and, to a lesser extent, Extraversion and Openness were protective. These associations were generally stronger among women and older participants; there was less evidence for ethnicity as a moderator. Personality had similar relations with the behavioural factors, and physical activity, diet and regular meal rhythms accounted for approximately 50% of the association between Neuroticism and Conscientiousness and BMI.

CONCLUSION

This study supports the links between personality traits and BMI and suggests that physical activity, more than diet, is a key factor in these associations.

Personality traits and circadian blood pressure patterns: a 7-year prospective study

OBJECTIVE

A nighttime dip in blood pressure is associated with decreased risk of cardiovascular morbidity and mortality. We examined whether personality traits predict nighttime dipping blood pressure.

METHODS

A community-based sample of 2848 adults from Sardinia (Italy) completed the Revised NEO Personality Inventory and 7 years later were examined with 24-hour ambulatory blood pressure monitoring. The primary analyses examined the associations of personality traits with continuous and categorical measures of mean arterial, systolic, and diastolic blood pressure nighttime dipping.

RESULTS

Agreeableness and conscientiousness were associated with more nocturnal blood pressure dipping (β = .05 [p = .025] and β = .07 [p < .001], respectively) and lower systolic blood pressure at night (β = -.05 [p = .018] and β = -.03 [p = .072], respectively). Nondippers were particularly more impulsive (p = .009), less trusting (p = .004), and less self-disciplined (p = .001), but there was no significant association between nocturnal dipping blood pressure and trait anxiety (p = .78) or depression (p = .59). The associations were stronger when comparing extreme dippers (nighttime drop ≥ 20%) to reverse dippers (nighttime increase in blood pressure). Indeed, scoring 1 standard deviation higher on conscientiousness was associated with approximately 40% reduced risk of reverse dipping (odds ratio = 1.43, confidence interval = 1.08-1.91).

CONCLUSIONS

We found evidence that reduced nighttime blood pressure dipping is associated with antagonism and impulsivity-related traits but not with measures of emotional vulnerability. The strongest associations were found with conscientiousness, a trait that may have a broad impact on cardiovascular health.

Personality traits and body mass index in a Korean population

Background

Overweight and obesity is a serious problem worldwide related to cardiovascular and other diseases. Personality traits are associated with the abnormal body mass indices (BMIs) indicative of overweight and obesity. However, the links between personality traits and BMI have been little studied in Korea.

Methods

We evaluated the association between personality traits and BMI in men and women using the rural Ansung and urban Ansan cohort from the Korean Genome Epidemiology Study, and the Kangbuk Samsung Hospital Cohort Study datasets. A shorter version of the original Revised Neuroticism-Extroversion-Openness Personality Inventory (NEO-PI-R) was used to measure the five-factor model of personality (neuroticism, extraversion, openness to experience, agreeableness, and conscientiousness).

Results

Data from a total of 1,495 men (mean age 60.0±9.8 years; mean BMI 24.3±3.0 kg/m²) and 2,547 women (mean age 47.0±15.5 years; mean BMI 22.8±3.4 kg/m²) were included in the analysis. Compared with the normal weight groups, overweight and obese men scored higher on openness to experience and lower on conscientiousness. Overweight and obese women scored lower on neuroticism and openness to experience and higher on agreeableness. Extraversion was positively associated with BMI in men (β = 0.032, P<0.05). BMI and waist circumference were significantly increased in individuals who were less dutiful. In women, neuroticism was inversely associated with BMI (β = −0.026, P<0.05). Openness to experience was negatively, and agreeableness was positively, associated with BMI (openness to experience: β = −0.072, agreeableness β = 0.068) and waist circumference (openness to experience: β = −0.202, agreeableness: β = 0.227) (P<0.05).

Conclusion

Personality traits were associated with underweight, overweight, and obesity in men and women. Increased understanding of the underlying factors contributing to this association will aid in the prevention and treatment of abnormal BMI.