Neuroticism, cognitive ability, and the metabolic syndrome: The Vietnam Experience Study

Association Between Diabetes and Personality Traits Among the Elderly in China: A Latent Class Analysis

BACKGROUND

The present study aimed to identify individuals with different personalities using latent class analysis and further distinguish those with a high risk of diabetes among different clusters.

METHODS

Data were utilized from a large-scale, cross-sectional epidemiological survey conducted in 2018 across 23 provinces in China, employing a multi-stage, stratified sampling technique. Latent class cluster analysis was performed to identify distinct personality clusters based on a series of variables concerning life attitudes. Logistic regression was used to calculate adjusted odds ratios (AORs) after controlling for potential confounding variables, including age, gender, body mass index, smoking status, alcohol consumption, hypertension, and physical activity levels, to determine the association between these groups and diabetes.

RESULTS

Four distinct personality clusters were identified, namely the energy-poor (2.0%), self-domination (61.3%), optimistic (21.3%), and irritable (15.4%) groups. The prevalence of diabetes in these groups was 14.6%, 9.7%, 9.3%, and 11.6%, respectively. After adjusting for potential confounders, the "energy-poor group" exhibited more odds of having diabetes as compared to the "optimistic group" (AOR 1.683, 95%CI: 1.052-2.693; P=0.030).

CONCLUSION

This study identified an energy-poor group of individuals with a high risk of diabetes. Targeted interventions should consider the emotional and personality characteristics of the elderly.

Neuroticism and white matter hyperintensities

Neuroticism is a major risk factor for neurodegenerative disorders, such as Alzheimer's disease and related dementias. This study investigates whether neuroticism is associated with white matter hyperintensities and whether this measure of brain integrity is a mediator between neuroticism and cognitive function. Middle-aged and older adults from the UK Biobank (N = 40,602; aged 45-82 years, M = 63.97, SD = 7.66) provided information on demographic and health covariates, completed measures of neuroticism and cognition, and underwent magnetic resonance imaging from which the volume of white matter hyperintensities was derived. Regression analyses that included age and sex as covariates found that participants who scored higher on neuroticism had more white matter hyperintensities (β = 0.024, 95% CI 0.015 to 0.032; p < .001), an association that was consistent across peri-ventricular and deep brain regions. The association was reduced by about 40% when accounting for vascular risk factors (smoking, obesity, diabetes, high blood pressure, heart attack, angina, and stroke). The association was not moderated by age, sex, college education, deprivation index, or APOE e4 genotype, and remained unchanged in sensitivity analyses that excluded individuals with dementia or those younger than 65. The mediation analysis revealed that white matter hyperintensities partly mediated the association between neuroticism and cognitive function. These findings identify white matter integrity as a potential neurobiological pathway that accounts for a small proportion of the association between neuroticism and cognitive health.

Personality and weight management in adults with type 2 diabetes: A systematic review

Aims

Managing weight in the context of type 2 diabetes presents unique hormonal, medicinal, behavioural and psychological challenges. The relationship between weight management and personality has previously been reviewed for general and cardiovascular disease populations but is less well understood in diabetes. This systematic review investigated the relationship between personality constructs and weight management outcomes and behaviours among adults with type 2 diabetes.

Methods

Medline, PubMed, Embase, PsycINFO and SPORTDiscus databases were searched to July 2021. Eligibility: empirical quantitative studies; English language; adults with type 2 diabetes; investigation of personality-weight management association. Search terms included variants of: diabetes, physical activity, diet, body mass index (BMI), adiposity, personality constructs and validated scales. A narrative synthesis, with quality assessment, was conducted.

Results

Seventeen studies were identified: nine cross-sectional, six cohort and two randomised controlled trials (N=6,672 participants, range: 30-1,553). Three studies had a low risk of bias. Personality measurement varied. The Big Five and Type D personality constructs were the most common measures. Higher emotional instability (neuroticism, negative affect, anxiety, unmitigated communion and external locus of control) was negatively associated with healthy diet and physical activity, and positively associated with BMI. Conscientiousness had positive associations with healthy diet and physical activity and negative associations with BMI and anthropometric indices.

Conclusions

Among adults with type 2 diabetes, evidence exists of a relationship between weight management and personality, specifically, negative emotionality and conscientiousness. Consideration of personality may be important for optimising weight management and further research is warranted.

Systematic review registration

www.crd.york.ac.uk/prospero/, identifier CRD42019111002.

Personality traits at age 16 and risk of metabolic syndrome at age 46

OBJECTIVE

To examine whether five-factor model personality traits at age 16 are associated with risk of metabolic syndrome 30 years later at age 46 and whether adolescent personality mediates the association between childhood social class and midlife metabolic health.

METHODS

Participants were from the British Cohort Study 1970, a birth cohort study of participants all born in the same week in 1970. Personality was assessed by participants' mothers (n = 3819) and participants' themselves (n = 2697) at age 16. The five components of the metabolic syndrome were measured at the age 46 assessment: elevated blood pressure, glucose, triglycerides, waist circumference and lower HDL cholesterol.

RESULTS

Mother-rated neuroticism and mother-rated conscientiousness at age 16 were associated with risk of metabolic syndrome at age 46 (OR = 1.19, 95% CI = 1.04, 1.36 and OR = 0.70, 95% CI = 0.62, 0.78, respectively). Self-reported neuroticism was also associated with metabolic syndrome risk (OR = 1.43, 95% CI = 1.08, 1.91). Mother-rated conscientiousness at age 16 accounted for 10% of the association between childhood social class and metabolic health at age 46. None of the other traits were significant mediators.

CONCLUSION

Consistent with lifespan models of personality and health, age 16 personality traits were associated with metabolic health measured 30 years later. Personality traits may also function as a mechanism through which early-life socioeconomic status contributes to midlife health.

Is neuroticism differentially associated with risk of Alzheimer's disease, vascular dementia, and frontotemporal dementia?

This study examines whether neuroticism is differentially associated with risk of incident Alzheimer's disease (AD), vascular dementia (VD), and frontotemporal dementia (FTD) using a prospective study design. Participants from the UK Biobank (N = 401,422) completed a self-report neuroticism scale in 2006-2010 and incident all-cause dementia, AD, VD, and FTD were ascertained using electronic health records or death records up to 2018. During an average follow-up of 8.8 years (3,566,123 person-years), there were 1798 incident of all-cause dementia, 675 AD, 376 VD, and 81 FTD. Accounting for age and sex, compared to individuals in the low quartile, individuals in the top quartile of neuroticism had higher risk of all-cause dementia (HR = 1.70; 95% CI: 1.49-1.93), AD (HR = 1.42; 1.15-1.75), VD (HR = 1.73; 1.30-2.29), but not FTD (HR = 0.89; 0.49-1.63). The associations with AD and VD were attenuated but remained significant after further accounting for education, household income, deprivation index, diabetes, hypertension, stroke, heart attack, ever smoker, physical activity, obesity, hemoglobin A1c, C-reactive protein, and low-density lipoprotein. The associations were not moderated by socioeconomic status. The findings were consistent in analyses that excluded cases that occurred within the first 5 years of follow-up. In conclusion, neuroticism is a robust predictor of incident AD and VD, but not FTD. This pattern suggests that the affective symptoms that distinguish dementia types may partly reflect premorbid differences in trait neuroticism.

The IDF Definition Is Better Suited for Screening Metabolic Syndrome and Estimating Risks of Diabetes in Asian American Adults: Evidence from NHANES 2011-2016

OBJECTIVE

extensive effort has been made to better define metabolic syndrome (MetS). Whether current definitions accurately diagnose MetS and predict risk of cardiovascular disease (CVD) or diabetes in diverse ethnic groups remains largely unknown. The objective of this study was to compare the prevalence of MetS and risk of CVD and diabetes among Asian American adults using two MetS definitions, one proposed by the Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (ATP III) and one by the International Diabetes Federation (IDF).

METHODS

we obtained a nationally representative sample of 2121 Asian American adults in the noninstitutionalized civilian population of the United States from the National Health and Nutrition Examination Survey (2011-2016). We computed age-adjusted, gender-specific MetS prevalence and each MetS component using ATP III and IDF definitions.

RESULTS

based on the IDF definition, MetS prevalence was 39.26% among Asian American men and 39.66% among Asian American women included in the study sample. Based on the ATP III definition, MetS prevalence in our sample was 39.38% among men and 36.11% among women. We found good concordance between the IDF and the ATP III definitions in identifying MetS in Asian American adults. Those with MetS defined only by the IDF definition had significantly higher body mass index (BMI) and waist circumference than those with MetS defined only by the ATP III definition. The IDF definition also better predicted elevated fasting insulin.

CONCLUSIONS

the IDF definition is more pertinent than the ATP III definition for screening and estimating risk of CVD and diabetes in Asian American adults. Future studies should examine differences in MetS prevalence across Asian ethnic groups to facilitate the development of culturally tailored strategies improve MetS prevention and detection in Asian Americans.

Impulsivity and midlife cardiometabolic risk: The role of maladaptive health behaviors

OBJECTIVE

The present study evaluated distinct facets of impulsivity related to cardiometabolic risk (CMR) to identify specific behavioral mechanisms driving these relationships.

METHOD

Community adults (N = 1,295) between 30 and 54 years old (53% female, 84% White) completed a battery of impulsivity measures, reported their engagement in health behaviors over the past week (i.e., cigarette smoking, alcohol use, physical activity, and dietary intake), and were assessed for CMR factors (i.e., blood pressure, insulin resistance, adiposity, and blood lipids). Structural equation modeling was used to estimate previously established hierarchical models of distinct facets of impulsivity and CMR. Indirect effects through the observed health behaviors were examined for each association between the latent impulsivity factors identified and the latent CMR factor.

RESULTS

Neuroticism/negative emotionality was the only latent impulsivity factor directly related to heightened CMR (β = 0.09, 95% confidence interval [CI] [0.01, 0.16], p = .020). Extraversion/positive emotionality indirectly related to lower CMR through greater physical activity (β = -0.04, 95% CI [-0.06, -0.02], p < .001), and measures of inhibition (β = 0.02, 95% CI [0.001, 0.04], p = .045) and delay discounting (β = 0.08, 95% CI [0.001, 0.15], p = .049) indirectly related to CMR through saturated fat intake.

CONCLUSIONS

These findings indicate that distinct facets of impulsivity differentially relate to CMR through varied behavioral pathways and identify physical activity and saturated fat intake as being particularly important health behaviors to target when tailoring treatment approaches to the unique behavioral characteristics of individuals high on certain facets of impulsivity. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Personality, Chrono-nutrition and Cardiometabolic Health: A Narrative Review of the Evidence

Growing evidence suggests that personality traits play a role in obesity and cardiometabolic health. In addition, irregularity of food intake has emerged as a potential risk factor for obesity, cardiovascular disease, and metabolic syndrome. Recent studies suggest that when we eat, termed "chrono-nutrition," may be as important to what we eat. This concept covers 3 aspects: 1) irregularity of energy intake in meals (varying amounts of energy intake throughout the day and at different times from one day to the next), 2) frequency (number of meals per day), and 3) timing of food intake (actual time of day). A narrative review was conducted to identify literature evaluating the effect of personality on chrono-nutrition and subsequently obesity and cardiometabolic health. The search focused on research published since 2000 in MEDLINE using the search terms "personality," "chrono-nutrition," "cardiometabolic," "BMI," "obesity," and "metabolic rate." Findings indicate an inverse relation between conscientiousness and obesity, with people who are more conscientious having a lower risk of obesity. Furthermore, time of day of energy intake has been linked to obesity, since meals consumed in the evening have been associated with lower resting metabolic rate. Inconsistent timing and frequency of meals have also been linked to increased body weight and worse cardiometabolic health. Together, the data indicate that eating meals at the same time every day at regular intervals might be the reason why those who score high in conscientiousness are able to maintain a healthier weight. Despite the reviewed observational evidence, there is an apparent gap in the existing literature on the interplay between personality, chrono-nutrition, and obesity and particularly on how dietary interventions should be designed considering different personality traits. Future research is needed to clarify this association and how it interacts with other factors, thus elucidating the role of chrono-nutrition in health.

Investigating the association between neuroticism and adverse obstetric and neonatal outcomes

Neuroticism is not only associated with affective disorders but also with certain somatic health problems. However, studies assessing whether neuroticism is associated with adverse obstetric or neonatal outcomes are scarce. This observational study comprises first-time mothers (n = 1969) with singleton pregnancies from several cohorts based in Uppsala, Sweden. To assess neuroticism-related personality, the Swedish universities Scales of Personality was used. Swedish national health registers were used to extract outcomes and confounders. In logistic regression models, odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for the outcomes by an increase of 63 units of neuroticism (equalling the interquartile range). Analyses were adjusted for maternal age, educational level, height, body mass index, year of delivery, smoking during pregnancy, involuntary childlessness, and psychiatric morbidity. Main outcomes were mode of delivery, gestational diabetes mellitus, gestational hypertension, preeclampsia, induction of delivery, prolonged delivery, severe lacerations, placental retention, postpartum haemorrhage, premature birth, infant born small or large for gestational age, and Apgar score. Neuroticism was not independently associated with adverse obstetric or neonatal outcomes besides gestational diabetes. For future studies, models examining sub-components of neuroticism or pregnancy-specific anxiety are encouraged.

Early maternal sensitivity, attachment security in young adulthood, and cardiometabolic risk at midlife

Children who experience high-quality early parenting tend to have better physical health, but limited research has tested whether this association extends into adulthood using prospective, observational assessments. Likewise, mechanisms that may explain such links have not yet been illuminated. In this study, we test whether the quality of early maternal sensitivity experienced during the first 3½ years of life predicts cardiometabolic risk at midlife (ages 37 and 39 years) via attachment representations measured in young adulthood (ages 19 and 26 years). We do so by comparing the predictive significance of two different forms of attachment representations coded from the Adult Attachment Interview (AAI): (a) secure base script knowledge and (b) coherence of mind. Using data from the Minnesota Longitudinal Study of Risk and Adaptation, we find that early maternal sensitivity is negatively associated with cardiometabolic risk at midlife. Secure base script knowledge (but not coherence of mind) partially mediated this link. These findings are consistent with the possibility that early parenting has lasting significance for physical health in part by promoting higher levels of secure base script knowledge.

Sex-specific moderation by lifestyle and psychosocial factors on the genetic contributions to adiposity in 112,151 individuals from UK Biobank

Evidence suggests that lifestyle factors, e.g. physical activity, moderate the manifestation of genetic susceptibility to obesity. The present study uses UK Biobank data to investigate interaction between polygenic scores (PGS) for two obesity indicators, and lifestyle and psychosocial factors in the prediction of the two indicators, with attention to sex-specific effects. Analyses were of 112 151 participants (58 914 females; 40 to 73 years) whose genetic data passed quality control. Moderation effects were analysed in linear regression models predicting body mass index (BMI) and waist-to-hip ratio (WHR), including interaction terms for PGS and each exposure. Greater physical activity, more education, higher income, moderate vs low alcohol consumption, and low material deprivation were each associated with a relatively lower risk for manifestation of genetic susceptibility to obesity (p < 0.001); the moderating effects of physical activity and alcohol consumption were greater in women than men (three-way interaction: p = 0.009 and p = 0.008, respectively). More income and less neuroticism were related to reduced manifestation of genetic susceptibility to high WHR (p = 0.007; p = 0.003); the effect of income was greater in women (three-way interaction: p = 0.001). Lifestyle and psychosocial factors appear to offset genetic risk for adiposity in mid to late adulthood, with some sex-specific associations.

Childhood Misfortune, Personality, and Heart Attack: Does Personality Mediate Risk of Myocardial Infarction?

Objective

Previous research has revealed a link between childhood experiences and adult health, but the mechanisms underlying this relationship are less clear. To elucidate this relationship, we investigated the pathway from childhood misfortune to nonfatal myocardial infarction (MI) via individual differences in personality.

Method

Longitudinal data were drawn from the National Survey of Midlife Development in the United States, which sampled 3,032 men and women aged 25-74 years at baseline. Big 5 personality traits and multiple measures of childhood misfortune were used to assess whether personality mediated the effect of childhood misfortune on MI risk.

Results

A series of proportional hazards models revealed that neuroticism mediated the effect of additive childhood misfortune on adult MI risk.

Discussion

Childhood misfortune may be formative in the development of personality, which, subsequently, can be consequential to health. These findings highlight the salient roles of early-life experiences and personality to shape health and aging.

Relationships among personality traits, metabolic syndrome, and metabolic syndrome scores: The Kakegawa cohort study

OBJECTIVE

Metabolic syndrome and the presence of metabolic syndrome components are risk factors for cardiovascular disease (CVD). However, the association between personality traits and metabolic syndrome remains controversial, and few studies have been conducted in East Asian populations.

METHODS

We measured personality traits using the Japanese version of the Eysenck Personality Questionnaire (Revised Short Form) and five metabolic syndrome components-elevated waist circumference, elevated triglycerides, reduced high-density lipoprotein cholesterol, elevated blood pressure, and elevated fasting glucose-in 1322 participants aged 51.1±12.7years old from Kakegawa city, Japan. Metabolic syndrome score (MS score) was defined as the number of metabolic syndrome components present, and metabolic syndrome as having the MS score of 3 or higher. We performed multiple logistic regression analyses to examine the relationship between personality traits and metabolic syndrome components and multiple regression analyses to examine the relationship between personality traits and MS scores adjusted for age, sex, education, income, smoking status, alcohol use, and family history of CVD and diabetes mellitus. We also examine the relationship between personality traits and metabolic syndrome presence by multiple logistic regression analyses.

RESULTS

"Extraversion" scores were higher in those with metabolic syndrome components (elevated waist circumference: P=0.001; elevated triglycerides: P=0.01; elevated blood pressure: P=0.004; elevated fasting glucose: P=0.002). "Extraversion" was associated with the MS score (coefficient=0.12, P=0.0003). No personality trait was significantly associated with the presence of metabolic syndrome.

CONCLUSIONS

Higher "extraversion" scores were related to higher MS scores, but no personality trait was significantly associated with the presence of metabolic syndrome.

Apolipoprotein E genotype does not moderate the associations of depressive symptoms, neuroticism and allostatic load with cognitive ability and cognitive aging in the Lothian Birth Cohort 1936

OBJECTIVES

In this replication-and-extension study, we tested whether depressive symptoms, neuroticism, and allostatic load (multisystem physiological dysregulation) were related to lower baseline cognitive ability and greater subsequent cognitive decline in older adults, and whether these relationships were moderated by the E4 allele of the apolipoprotein E (APOE) gene. We also tested whether allostatic load mediated the relationships between neuroticism and cognitive outcomes.

METHODS

We used data from the Lothian Birth Cohort 1936 (n at Waves 1-3: 1,028 [M age = 69.5 y]; 820 [M duration since Wave 1 = 2.98 y]; 659 [M duration since Wave 1 = 6.74 y]). We fitted latent growth curve models of general cognitive ability (modeled using five cognitive tests) with groups of APOE E4 non-carriers and carriers. In separate models, depressive symptoms, neuroticism, and allostatic load predicted baseline cognitive ability and subsequent cognitive decline. In addition, models tested whether allostatic load mediated relationships between neuroticism and cognitive outcomes.

RESULTS

Baseline cognitive ability had small-to-moderate negative associations with depressive symptoms (β range = -0.20 to -0.17), neuroticism (β range = -0.27 to -0.23), and allostatic load (β range = -0.11 to 0.09). Greater cognitive decline was linked to baseline allostatic load (β range = -0.98 to -0.83) and depressive symptoms (β range = -1.00 to -0.88). However, APOE E4 allele possession did not moderate the relationships of depressive symptoms, neuroticism and allostatic load with cognitive ability and cognitive decline. Additionally, the associations of neuroticism with cognitive ability and cognitive decline were not mediated through allostatic load.

CONCLUSIONS

Our results suggest that APOE E4 status does not moderate the relationships of depressive symptoms, neuroticism, and allostatic load with cognitive ability and cognitive decline in healthy older adults. The most notable positive finding in the current research was the strong association between allostatic load and cognitive decline.

Pettiness: Conceptualization, measurement and cross-cultural differences

Although pettiness, defined as the tendency to get agitated over trivial matters, is a facet of neuroticism which has negative health implications, no measure exists. The goal of the current study was to develop, and validate a short pettiness scale. In Study 1 (N = 2136), Exploratory Factor Analysis distilled a one-factor model with five items. Convergent validity was established using the Big Five Inventory, DASS, Satisfaction with Life Scale, and Conner-Davidson Resilience Scale. As predicted, pettiness was positively associated with neuroticism, depression, anxiety and stress but negatively related to extraversion, agreeableness, conscientiousness, openness, life satisfaction and resilience. Also, as predicted, pettiness was not significantly related to physical functioning, or blind and constructive patriotism, indicating discriminant validity. Confirmatory Factor Analysis in Study 2 (N = 734) revealed a stable one-factor model of pettiness. In Study 3 (N = 532), the scale, which showed a similar factor structure in the USA and Singapore, also reflected predicted cross-cultural patterns: Pettiness was found to be significantly lower in the United States, a culture categorized as "looser" than in Singapore, a culture classified as "tighter" in terms of Gelfand and colleagues' framework of national tendencies to oppose social deviance. Results suggest that this brief 5-item tool is a reliable and valid measure of pettiness, and its use in health research is encouraged.

Adverse metabolic and mental health outcomes associated with shiftwork in a population-based study of 277,168 workers in UK biobank<sup/>

BACKGROUND

Reported associations between shiftwork and health have largely been based on occupation-specific, or single sex studies that might not be generalizable to the entire working population. The objective of this study was to investigate whether shiftwork was independently associated with obesity, diabetes, poor sleep, and well-being in a large, UK general population cohort.

METHODS

Participants of the UK Biobank study who were employed at the time of assessment were included. Exposure variables were self-reported shiftwork (any shiftwork and night shiftwork); and outcomes were objectively measured obesity, inflammation and physical activity and self-reported lifestyle, sleep and well-being variables, including mental health.

RESULTS

Shiftwork was reported by 17% of the 277,168 employed participants. Shiftworkers were more likely to be male, socioeconomically deprived and smokers, and to have higher levels of physical activity. Univariately, and following adjustment for lifestyle and work-related confounders, shiftworkers were more likely to be obese, depressed, to report disturbed sleep, and to have neurotic traits.

CONCLUSIONS

Shiftwork was independently associated with multiple indicators of poor health and wellbeing, despite higher physical activity, and even in shiftworkers that did not work nights. Shiftwork is an emerging social factor that contributes to disease in the urban environment across the working population. Key messages Studies have linked shiftwork to obesity and diabetes in nurses and industry workers, but little is known about the implications of shiftwork for the general workforce In this large cross sectional study of UK workers, shiftwork was associated with obesity, depression and sleep disturbance, despite higher levels of physical activity. Shiftwork was associated with multiple indicators of compromised health and wellbeing and were more likely to report neurotic traits and evening preference.

Gender-specific association between serotonin transporter polymorphisms (5-HTTLPR and rs25531) and neuroticism, anxiety and depression in well-defined healthy Han Chinese

BACKGROUND

A tri-allelic serotonin transporter promoter polymorphism (5-HTTLPR/rs25531) more effectively determines the levels of transcriptional efficacy than that with the bi-allelic 5-HTTLPR polymorphism in vitro. Both are reportedly associated with personality traits of negative emotionality, but with conflicting findings. One explanation for this is that a gender difference may play a role in genetic contribution. Here, we hypothesized that the tri-allelic genotype of the serotonin transporter is more closely linked to neuroticism, an anxiety- and depression-related trait, than the bi-allelic variation, particularly in a gender-dependent way.

METHODS

The genotypes of the 5-HTTLPR and rs25531 loci were determined in 1139 well-defined physically and mentally healthy Han Chinese (550 men, 589 women; mean age 38.3±10.3 years). All participants completed the neuroticism measure of the short-form Maudsley Personality Inventory (MPI). The levels of anxiety and depression were assessed by the Beck Anxiety Inventory (BAI) and the Beck Depression Inventory (BDI), respectively.

RESULTS

A significant tri-allelic genotype-by-gender interaction effect was found in the MPI-neuroticism measure. S'S' homozygotes were associated with higher neuroticism than L' allele carriers in men. Also, both the BAI and BDI scores were higher in the S'S' homozygotic men. In the bi-allelic analyses, however, there was only an association between SS genotype and MPI-neuroticism in men.

LIMITATIONS

Sub-analyses by gender-stratification may reduce the statistical power.

CONCLUSIONS

Our findings confirm that gender differences exist in the genetic contributions of the serotonin transporter in human neuroticism, and anxiety/depression. Our data provide further support for rs25531, strengthening the effects of 5-HTTLPR.

Personality and metabolic dysfunction in young adulthood: A cross-sectional study

This research used the National Longitudinal Study of Adolescent to Adult Health ( N = 15,359; age range 25–34) to examine the cross-sectional relation between personality and four components of metabolic syndrome (elevated glucose, blood pressure, cholesterol, and waist circumference) and a metabolic risk index in young adulthood. Consistent with research on older adults, higher Neuroticism and lower Conscientiousness were associated with greater risk of metabolic dysfunction; Agreeableness, however, was unrelated to it. The relation between personality and metabolic health may unfold across the lifespan, with the association between Neuroticism/Conscientiousness and metabolic dysfunction starting early and the association with Agreeableness emerging at older ages.

Do personality traits moderate the manifestation of type 2 diabetes genetic risk?

OBJECTIVE

To test whether personality traits moderate type 2 diabetes (T2D) genetic risk.

METHODS

Using a large community-dwelling sample (n=837, Mage=69.59±0.85years, 49% males) we fitted a series of linear regression models predicting glycated haemoglobin (HbA1c) from T2D polygenic risk - aggregation of small individual effects of a large number of single nucleotide polymorphisms (SNPs) - and five personality traits. We tested the main effects of personality traits and their interactions with T2D polygenic risk score, controlling for age and sex. The models in the final set were adjusted for cognitive ability, highest educational qualification, and occupational class.

RESULTS

Lower levels of openness were associated with heightened levels of HbA1c (β=-0.014, p=.032). There was a significant interaction between T2D polygenic risk score and agreeableness: lower agreeableness was related to a stronger association between T2D polygenic risk and HbA1c (β=-0.08, p=.021). In the model adjusted for cognitive ability, the main effect of openness was not significant (β=-0.08, p=.057). The interaction between agreeableness and T2D polygenic risk was still present after controlling for cognitive ability and socioeconomic status indicators, and the interaction between conscientiousness and polygenic risk score was also significant: lower conscientiousness was associated with a stronger association between T2D polygenic risk and HbA1c levels (β=0.09, p=.04).

CONCLUSIONS

Personality may be associated with markers of diabetes, and may moderate the expression of its genetic risk.

Personality Correlates of Midlife Cardiometabolic Risk: The Explanatory Role of Higher-Order Factors of the Five-Factor Model

Varying associations are reported between Five-Factor Model (FFM) personality traits and cardiovascular disease risk. Here, we further examine dispositional correlates of cardiometabolic risk within a hierarchical model of personality that proposes higher-order traits of Stability (shared variance of Agreeableness, Conscientiousness, inverse Neuroticism) and Plasticity (Extraversion, Openness), and we test hypothesized mediation via biological and behavioral factors. In an observational study of 856 community volunteers aged 30-54 years (46% male, 86% Caucasian), latent variable FFM traits (using multiple-informant reports) and aggregated cardiometabolic risk (indicators: insulin resistance, dyslipidemia, blood pressure, adiposity) were estimated using confirmatory factor analysis (CFA). The cardiometabolic factor was regressed on each personality factor or higher-order trait. Cross-sectional indirect effects via systemic inflammation, cardiac autonomic control, and physical activity were tested. CFA models confirmed the Stability "meta-trait," but not Plasticity. Lower Stability was associated with heightened cardiometabolic risk. This association was accounted for by inflammation, autonomic function, and physical activity. Among FFM traits, only Openness was associated with risk over and above Stability, and, unlike Stability, this relationship was unexplained by the intervening variables. A Stability meta-trait covaries with midlife cardiometabolic risk, and this association is accounted for by three candidate biological and behavioral factors.

Associations between the five-factor model of personality and leukocyte telomere length in elderly men and women: The Helsinki Birth Cohort Study (HBCS)

OBJECTIVE

Personality traits have been associated with cardiometabolic diseases and mental disorders as well as with longevity. However, the underlying mechanisms are not fully understood. Accelerated cellular aging may play a role in this process. We studied whether personality traits in late adulthood, as defined in the five-factor model (FFM), were associated with a biomarker of cellular vitality, leukocyte telomere length (LTL).

METHODS

At a mean age of 63.4 (SD=2.8) years, 1671 (742 men, 929 women) participants from the Helsinki Birth Cohort Study filled in the Neuroticism, Extraversion and Openness Personality Inventory (NEO-PI). LTL was measured at a mean age of 61.5 (SD=2.9) years by using a real-time quantitative PCR method.

RESULTS

None of the FFM personality dimensions were significantly associated with the LTL in the analyses of both sexes combined. We however found interaction between sex and agreeableness (B=0.020, 95% CI=.008, 0.032, p=.001) and in the sex-specific analyses, men who scored higher on agreeableness (B=-0.086, 95% CI=-0.155, -0.016, p=.016) and women who scored lower on agreeableness (B=0.074, 95% CI=0.014, 0.134, p=.016) had shorter LTL.

CONCLUSIONS

FFM dimensions of personality were not associated with LTL in a sample of elderly individuals. The counterintuitive and sporadic sex specific finding on agreeableness requires replication. Overall our findings suggest that LTL, a biomarker of cellular aging, may not offer insight into the associations between personality, longevity and health.

Personality and diabetes mellitus incidence in a national sample

OBJECTIVE

To test whether personality traits were prospectively associated with type 2 diabetes incidence.

METHODS

The sample (n=6798) was derived from the National Health and Nutrition Examination Survey Epidemiological Follow-up Study cohort. We fit four logistic regression models to test whether neuroticism, extraversion, openness to experience, or the Type A behavior pattern predicted type 2 diabetes incidence. Model 1 included sex, age, and race/ethnicity. Model 2 added personality traits, Model 3 added depressive symptoms, and Model 4 added body mass index (BMI), hypertension, and cigarette smoking status as predictors.

RESULTS

In Model 1 age was associated with increased risk of diabetes (2% per year); being black as opposed to white was associated with a three-fold increase in risk. In Model 2 age and being black were still significant and extraversion was associated with decreased risk (17% per standard deviation [SD]). In Model 3 age, being black, and extraversion were still significant. In addition, neuroticism was associated with decreased risk (26% per SD) and depressive symptoms were associated with increased risk (28% per SD). In Model 4 age, being black, neuroticism, and depressive symptoms were still significant. BMI was associated with increased risk (14% per SD) and extraversion was no longer significant.

CONCLUSIONS

Higher neuroticism was associated with reduced type 2 diabetes risk even after controlling for race/ethnicity, age, depressive symptoms, and BMI. Extraversion and Type A behavior were not significant after including covariates.

Neuroticism and Extraversion in Youth Predict Mental Wellbeing and Life Satisfaction 40 Years Later

Neuroticism and Extraversion are linked with current wellbeing, but it is unclear whether these traits in youth predict wellbeing decades later. We applied structural equation modelling to data from 4583 people from the MRC National Survey of Health and Development. We examined the effects of Neuroticism and Extraversion at ages 16 and 26 years on mental wellbeing and life satisfaction at age 60-64 and explored the mediating roles of psychological and physical health. Extraversion had direct, positive effects on both measures of wellbeing. The impact of Neuroticism on both wellbeing and life satisfaction was largely indirect through susceptibility to psychological distress and physical health problems. Personality dispositions in youth have enduring influence on wellbeing assessed about forty years later.

Is change bad? Personality change is associated with poorer psychological health and greater metabolic syndrome in midlife

Personality change is emerging as an important predictor of health and well-being. Extending previous research, we examined whether two types of personality change, directional and absolute, are associated with both subjective and objective indicators of health. Utilizing the longitudinal Midlife in the United States survey (MIDUS) data, we examined whether both types of change over 10 years were associated with psychological well-being, self-reported global health, and the presence of metabolic syndrome (MetS) components and diagnosis. Socially undesirable personality change (e.g., becoming less conscientious and more neurotic) and absolute personality change were independently associated with worse perceived health and well-being at Time 2. Notably, absolute personality change, regardless of the direction, was also associated with having a greater number of MetS components and a greater probability of diagnosis at Time 2. In sum, too much personality change may be bad for one's health: Socially undesirable and absolute personality change were both associated with worse psychological health and worse metabolic profiles over 10 years. These findings suggest that personality change may contribute to psychological and physical health, and provide initial insight into potential intermediate links between personality change and distal outcomes such as mortality.

Do genetic factors contribute to the relation between education and metabolic risk factors in young adults? A twin study

BACKGROUND

Lower educated people have a higher prevalence of metabolic risk factors (MRF), that is, high waist circumference (WC), high systolic blood pressure, low high-density lipoprotein cholesterol level, high triglycerides and high fasting glucose levels. Behavioural and psychosocial factors cannot fully explain this educational gradient. We aim to examine the possible role of genetic factors by estimating the extent to which education and MRF share a genetic basis and the extent to which the heritability of MRF varies across educational levels.

METHODS

We examined 388 twin pairs, aged 18-34 years, from the Belgian East Flanders Prospective Twin Survey. Using structural equation modelling, a Cholesky bivariate model was applied to assess the shared genetic basis between education and MRF. The heritability of MRF across education levels was estimated using a non-linear multivariate Gaussian regression.

RESULTS

Fifteen percent (P < 0.01) of the negative relation between education and WC was because of genes shared between these two traits. Furthermore, the heritability of WC was lower in the lowest educated group (65%) compared with the highest educated group (78%, P = 0.04). The lower heritabilities among the lower educated twins for the other MRF were not significant. The heritability of glucose was higher in the lowest education (80%) group compared with the high education group (67%, P = 0.01).

CONCLUSION

Our findings suggest that genetic factors partly explain educational differences in WC. Furthermore, the lower heritability estimates in WC in the lower educated young adults suggest opportunities for environmental interventions to prevent the development of full-blown metabolic syndrome in middle and older age.

Personality as a risk factor for the metabolic syndrome: a systematic review

OBJECTIVE

The metabolic syndrome is a cluster of risk factors for the development of cardiovascular disease and/or type 2 diabetes. Personality can be defined as a stable set of behavioral characteristics of a person. In this review we systematically reviewed whether different personality characteristics are associated with the risk of having or developing the metabolic syndrome.

METHODS

Systematic review.

RESULTS

In total 18 studies were included. Thirteen cross-sectional analyses, and ten longitudinal analyses were grouped according to personality constructs: hostility, anger, and Type A behavior, temperament, neuroticism, and Type D personality. Conflicting evidence was reported on persons with high hostility, neuroticism, or Type D personality scores to be associated with an increased metabolic syndrome prevalence and development. All significant findings do point in the same direction: a more negative, or hostile personality type is associated with an increased prevalence of metabolic syndrome and its development over time.

CONCLUSION

There was no clear association between personality measures and the occurrence and development of the metabolic syndrome. There is, however, a cluster of risk factors that include the presence of the metabolic syndrome, as well as a more negative prone personality style, that both predispose to the development of coronary heart disease and diabetes. Future studies should investigate the role of personality measures in the development of these conditions, while taking into account metabolic syndrome, lifestyle and socio-demographic factors.

Neuroticism combined with slower and more variable reaction time: synergistic risk factors for 7-year cognitive decline in females

OBJECTIVE

Among adults, slower and more variable reaction times are associated with worse cognitive function and increased mortality risk. Therefore, it is important to elucidate risk factors for reaction time change over the life course. Method. Data from the Health and Lifestyle Survey (HALS) were used to examine predictors of 7-year decline in reaction time (N = 4,260). Regression-derived factor scores were used to summarize general change across 4 reaction time variables: simple mean, 4-choice mean, simple variability, and 4-choice variability (53.52% of variance).

RESULTS

Age (B = .02, p < .001) and HALS1 baseline reaction time (B = -.10, p = .001) were significant risk factors for males (N = 1,899). In addition to these variables, in females (N = 2,361), neuroticism was significant and interacted synergistically with baseline reaction time (B = .06, p = .04). Adjustment for physiological variables explained the interaction with neuroticism, suggesting that candidate mechanisms had been identified. Discussion. A priority for future research is to replicate interactions between personality and reaction time in other samples and find specific mechanisms. Stratification of population data on cognitive health by personality and reaction time could improve strategies for identifying those at greater risk of cognitive decline.

Type D personality and metabolic syndrome in a 7-year prospective occupational cohort

OBJECTIVE

Type D personality is a combination of high negative affectivity (NA) and high social inhibition (SI). This trait is related to increased mortality and poor health outcomes in patients with cardiovascular diseases, although it is less well-established if Type D personality also poses an increased risk in healthy populations. A potential underlying pathway could include the metabolic syndrome and the combination of abdominal obesity, subnormal levels of triglycerides and HDL-cholesterol, elevated blood pressure, and increased plasma glucose levels. We investigated if Type D personality shows a cross-sectional and longitudinal association with metabolic syndrome in a working population.

METHODS

Poisson regression and linear regression were used to estimate the association between Type D personality and its subscales (NA) and (SI) with objectively established metabolic syndrome markers in cross-sectional (n=458) and prospective (n=268, 6.3 years follow-up) analyses of data from an occupational cohort (mean age=35.9 years, SD=11.7; 80% male).

RESULTS

Type D personality was neither associated with the metabolic syndrome nor with any of its subcomponents.

CONCLUSION

The present study does not support a role for metabolic syndrome as a mediating mechanism. More research is needed that examines potential pathways linking Type D personality with cardiovascular disease outcomes.

Personality and longevity: knowns, unknowns, and implications for public health and personalized medicine

We review evidence for links between personality traits and longevity. We provide an overview of personality for health scientists, using the primary organizing framework used in the study of personality and longevity. We then review data on various aspects of personality linked to longevity. In general, there is good evidence that higher level of conscientiousness and lower levels of hostility and Type D or "distressed" personality are associated with greater longevity. Limited evidence suggests that extraversion, openness, perceived control, and low levels of emotional suppression may be associated with longer lifespan. Findings regarding neuroticism are mixed, supporting the notion that many component(s) of neuroticism detract from life expectancy, but some components at some levels may be healthy or protective. Overall, evidence suggests various personality traits are significant predictors of longevity and points to several promising directions for further study. We conclude by discussing the implications of these links for epidemiologic research and personalized medicine and lay out a translational research agenda for integrating the psychology of individual differences into public health and medicine.