Personality and risk of diabetes in adults: pooled analysis of 5 cohort studies

Personality nuances and risk of dementia: Evidence from two longitudinal studies

Personality traits are broad constructs composed of nuances, operationalized by personality items, that can provide a more granular understanding of personality associations with health outcomes. This study examined the associations between personality nuances and incident dementia and evaluated whether nuances associations replicate across two samples. Health and Retirement Study (HRS, N = 11,400) participants were assessed in 2006/2008, and the English Longitudinal Study of Ageing (ELSA, N = 7453) participants were assessed in 2010/2011 on personality and covariates. Dementia incidence was tracked for 14 years in the HRS and 8 years in ELSA. In both HRS and ELSA, higher neuroticism domain and nuances (particularly nervous and worry) were related to a higher risk of incident dementia, whereas higher conscientiousness domain and nuances (particularly responsibility and organization) were associated with a lower risk of dementia. To a lesser extent, higher extraversion (active), openness (broad-minded, curious, and imaginative), and agreeableness (helpful, warm, caring, and sympathetic) nuances were associated with a lower risk of dementia, with replicable effects across the two samples. A poly-nuance score, aggregating the effects of personality items, was associated with an increased risk of incident dementia in the HRS and ELSA, with effect sizes slightly stronger than those of the personality domains. Clinical, behavioral, psychological, and genetic covariates partially accounted for these associations. The present study provides novel and replicable evidence for specific personality characteristics associated with the risk of incident dementia.

Examining sense of purpose and conscientiousness as unique correlates of health: A bifactor examination

Conscientiousness and sense of purpose consistently predict health, wellbeing, and health behavior. However, it remains an open question whether they are unique or overlapping predictors of health and wellbeing. The current study considered this question using the MOSAiCH study, a nationally representative sample of 2305 Swiss adults (M: 52.33 years old; SD = 17.36). Participants reported on sense of purpose and conscientiousness, in addition to multiple health, wellbeing, and health behavior indicators (e.g. dietary practices, activity engagement, health conditions, psychological concerns, and doctor visits). Results found conscientiousness and sense of purpose were moderately associated with multiple health, wellbeing, and health behavior indicators. Bifactor modeling was employed to test the incremental validity of conscientiousness and sense of purpose, when accounting for their shared variance. The specific factor for purpose predicted outcomes even when accounting for conscientiousness. However, conscientiousness had little incremental validity over the general factor.

Association of Personality Traits and Self-Care Behaviors in People With Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Diabetes self-care is critical for individuals with type 2 diabetes mellitus (T2DM), and exploring the impact of personality traits on this domain remains pivotal. This study aimed to investigate the association between personality traits and various dimensions of self-care in people with T2DM. A Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA)-guided systematic review with meta-analysis was conducted. Two reviewers independently screened articles, extracted data, and assessed the risk of bias. Estimates were pooled using random-effects meta-analysis. Twenty-three studies, that met our inclusion criteria, revealed distinct associations between certain personality traits and various aspects of self-care. Notably, traits such as openness, conscientiousness, and agreeableness showed associations with improved foot care compliance (odds ratio (OR) = 2.53, 95% CI = 1.49-4.28; OR = 1.84, 95% CI = 1.10-3.08; and OR = 2.07, 95% CI = 1.23-3.48, respectively). Openness was also linked to better overall self-care behaviors (OR = 2.00, 95% CI = 1.17-3.41), while conscientiousness correlated with reduced smoking (OR = 0.96, 95% CI = 0.93-0.99), and agreeableness was associated with improved medication adherence (OR = 1.68, 95% CI = 1.34-2.31). Conversely, traits like extraversion and neuroticism showed associations with decreased medication adherence (OR = 0.77, 95% CI = 0.61-0.96 and OR = 0.51, 95% CI = 0.40-0.65, respectively), with neuroticism additionally linked to lower overall self-care behaviors (OR = 0.67, 95% CI: 0.55-0.81). This study emphasizes the intricate role of personality traits in shaping self-care practices in individuals with T2DM, underscoring the significance of factoring these traits into tailoring and improving diabetes self-care strategies. Nevertheless, establishing definitive causal relationships mandates further in-depth longitudinal investigations and broader meta-analyses to achieve a more conclusive understanding.

Personality traits and the risk of sensory impairment: Evidence from the National Health and Aging Trends Study

OBJECTIVE

Sensory impairment has pervasive effects on older individuals' quality of life and health. Although recent research found an association between personality traits and the risk of hearing and vision impairment, data on older adults is limited, and no study has examined dual-sensory impairment. Therefore, the present study examined the prospective relationship between personality traits and risk of hearing, vision, and dual sensory impairment among older adults.

METHOD

Participants were older adults aged 67 to 94 years (N = 829) from the National Health and Aging Trends Study (NHATS). Personality traits, demographic, clinical (body mass index, diabetes, and high blood pressure), and behavioral (smoking and physical activity) factors were assessed in 2013/2014. Objective measures of hearing and vision were obtained in 2021.

RESULTS

Controlling for demographic factors, higher conscientiousness was associated with a lower risk of hearing (OR: 0.81; 95%CI: 0.67-0.97, p = .022), vision (OR: 0.83, 95%CI: 0.71-0.97, p = .022) and dual sensory impairment (OR: 0.70, 95%CI: 0.56-0.86, p < .001). Higher openness (OR: 0.81, 95%CI: 0.68-0.97, p = .023) and neuroticism (OR: 0.74, 95%CI: 0.62-0.88, p < .001) were associated with a lower risk of hearing impairment. Clinical and behavioral covariates partially accounted for these associations.

CONCLUSION

Consistent with other age-related health and cognitive outcomes, conscientiousness may be protective against sensory impairment. Surprisingly, neuroticism had a protective effect for hearing, but not vision. The findings provide novel evidence for an association between personality and sensory impairment among older adults.

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.

Association Between Big Five Personality Traits and Hypertension in Saudi Patients: A Case Control Study

Background

The association between personality traits and hypertension is complex and has so far not been studied in depth.

Objective

The present study aims to explore the connection between the Big Five personality traits and hypertension.

Methods

This case control study includes 310 participants, and the relationship between personality traits and hypertension was investigated in normotensive and hypertensive patients by the Big Five Inventory-10. We examined the association of each of the Big Five personality traits in hypertensive patients and a control group using binary logistic regression analysis.

Results

The findings of the study revealed that amongst the Big Five personality factors, low conscientiousness (OR: 1.09, 95% CI: 0.92-1.29, P<0.005) and high neuroticism (OR: 0.54, 95% CI: 0.45-0.66, P<0.001) were related with high risk of hypertension. Male, older people, and physically inactive individuals have been found to be at a higher risk of hypertension. No significant relationship was found between hypertension and marital status, education, or smoking habits.

Conclusion

These results suggested that a low score in conscientiousness trait and a high neuroticism score may be an additional risk factor of hypertension. Thus, it may be worthy to investigate further in order to identify patients at risk and develop a more individual treatment strategy. Cognitive behavioral therapy and pharmacological options can be used preemptively in high-risk patients.

Personality and Risk of Incident Stroke in 6 Prospective Studies

BACKGROUND

A large literature has examined a broad range of factors associated with increased risk of stroke. Few studies, however, have examined the association between personality and stroke. The present study adopted a systematic approach using a multi-cohort design to examine the associations between 5-Factor Model personality traits (neuroticism, extraversion, openness, agreeableness, and conscientiousness) and incident stroke using data from 6 large longitudinal samples of adults.

METHODS

Participants (age range: 16-104 years old, N=58 105) were from the MIDUS (Midlife in the United States) Study, the HRS (Health and Retirement Study), The US (Understanding Society) study, the WLS (Wisconsin Longitudinal Study), the NHATS (National Health and Aging Trends Study), and the LISS (Longitudinal Internet Studies for the Social Sciences). Personality traits, demographic factors, clinical and behavioral risk factors were assessed at baseline; stroke incidence was tracked over 7 to 20 years follow-up.

RESULTS

Meta-analyses indicated that higher neuroticism was related to a higher risk of incident stroke (hazard ratio, 1.15 [95% CI, 1.10-1.20]; P<0.001), whereas higher conscientiousness was protective (HR, 0.89 [95% CI, 0.85-0.93]; P<0.001). Additional meta-analyses indicated that BMI, diabetes, blood pressure, physical inactivity, and smoking as additional covariates partially accounted for these associations. Extraversion, openness, and agreeableness were unrelated to stroke incidence.

CONCLUSIONS

Similar to other cardiovascular and neurological conditions, higher neuroticism is a risk factor for stroke incidence, whereas higher conscientiousness is a protective factor.

Health literacy across personality traits among older adults: cross-sectional evidence from Switzerland

This research aims to better understand the association of personality traits (PT)-Openness to Experience, Conscientiousness, Extraversion, Agreeableness, and Neuroticism-with health literacy (HL) skills of adults aged 58 years and older in a nationally representative sample from Switzerland. Analyses were conducted on a subsample (n = 1546) of respondents living in Switzerland from wave 8 (2019/2020) of the Survey of Health, Ageing, and Retirement in Europe (SHARE). PT were assessed with the Big-Five inventory ten (BFI-10). HL was measured using the short version of the European Health Literacy Survey questionnaire (HLS-EU-Q16). We used multivariable regressions to explore how respondents' PT are independently associated with (1) the HLS-EU-Q16 and (2) seven sub-indices derived from this HL scale. Results demonstrated that even when controlling for social, regional, and health characteristics, PT were significantly associated with HL among older adults in Switzerland. More open individuals showed better HL competencies. By contrast, individuals who scored higher on neuroticism expressed more difficulties regarding concrete health-relevant tasks or situations. These findings call for public health policies targeting older adults with lower levels of openness who are less likely to engage in self-examination, and individuals with higher levels of neuroticism who tend to experience more negative emotions. Moreover, health information and communication strategies content development that accounts for different personality types and addresses the needs of individuals with low levels of openness and high neuroticism may help improve HL among older adults whose personalities may otherwise put them at a disadvantage in handling health information.

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.

Joint Exposure to Positive Affect, Life Satisfaction, Depressive Symptoms, and Neuroticism and Incident Type 2 Diabetes

CONTEXT

Whether the psychological wellbeing status could be a risk factor for type 2 diabetes is unclear.

OBJECTIVE

We aimed to measure the association between combined psychological wellbeing factors and type 2 diabetes and investigate whether this association was modified by genetic predisposition.

METHODS

Prospective cohort study from the UK Biobank. In total, 127 496 participants who completed a psychological wellbeing questionnaire and did not have type 2 diabetes at baseline (2006-2010) were included; among them, 88 584 (69.5%) were analyzed to determine their genetic predisposition. The main outcome measure was incident type 2 diabetes.

RESULTS

During the median follow-up of 10.0 years, 2547 incident type 2 diabetes cases were documented. Moderate to extreme unhappiness, satisfaction score ≤3, presence of broad depression, and a neuroticism score ≥3 were all significantly and independently associated with an increased risk of diabetes. When considered as a combination indicator, compared with individuals in the highest quartile of the psychological wellbeing score, the fully adjusted hazard ratios (95% CI) of type 2 diabetes were 1.41 (1.21-1.65) in the third quartile, 1.45 (1.24-1.69) in the second quartile, and 1.73 (1.48-2.01) in the lowest quartile. In the stratified analysis, we observed significant interactions between age and physical activity, and type 2 diabetes (Pinteraction < .001 and 0.049, respectively). However, there was no significant interaction between the psychological wellbeing score and genetic susceptibility to diabetes (Pinteraction = .980).

CONCLUSION

Worse overall psychological wellbeing was associated with a significantly increased risk of type 2 diabetes in a dose-response fashion regardless of genetic predisposition.

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.

Preliminary Support of a Behavioral Intervention for Trait Conscientiousness in Multiple Sclerosis

Background

Conscientiousness, or the proclivity for deliberation, achievement, and order, declines in many individuals with multiple sclerosis (MS). Decreased conscientiousness predicts future cognitive deterioration, brain atrophy, and employment loss in individuals with MS. As a psychological trait, it may be an actionable antecedent to these important outcomes. We pilot tested an application (app)-facilitated behavioral intervention to help adaptation to low conscientiousness and, in turn, improve employment.

Methods

Eleven individuals with MS (5 treatment, 6 control) with low conscientiousness were recruited for a 12-week randomized controlled trial. The treatment group received a newly developed behavioral treatment and smartphone app designed to help people behave more conscientiously, 2 teleconference booster sessions, and weekly telephone calls to monitor progress. Employment changes were recorded at baseline and follow-up. Patients provided detailed posttreatment interviews.

Results

Participant groups were matched on baseline age, sex, education, disease duration, hours worked, and conscientiousness. All participants in the treatment arm reported benefits, found the app easy to use, and would recommend it to others. The treatment group reported significantly more positive work outcomes relative to controls at follow-up (P = .028). Other positive life changes were described by treatment participants during post-treatment interviews.

Conclusions

These results support the hypothesis that behaviors typically associated with low conscientiousness may be addressed by behavioral therapy in the MS population. In addition to the positive employment changes in the treatment group, several other quality of life changes were described by study participants. Additional research is needed.

Agreeableness and Its Consequences: A Quantitative Review of Meta-Analytic Findings

Agreeableness impacts people and real-world outcomes. In the most comprehensive quantitative review to date, we summarize results from 142 meta-analyses reporting effects for 275 variables, which represent N > 1.9 million participants from k > 3,900 studies. Arranging variables by their content and type, we use an organizational framework of 16 conceptual categories that presents a detailed account of Agreeableness’ external relations. Overall, the trait has effects in a desirable direction for 93% of variables (grand mean [Formula: see text]). We also review lower order trait evidence for 42 variables from 20 meta-analyses. Using these empirical findings, in tandem with existing theory, we synthesize eight general themes that describe Agreeableness’ characteristic functioning across variables: self-transcendence, contentment, relational investment, teamworking, work investment, lower results emphasis, social norm orientation, and social integration. We conclude by discussing potential boundary conditions of findings, contributions and limitations of our review, and future research directions.

Personality Associations With Amyloid and Tau: Results From the Baltimore Longitudinal Study of Aging and Meta-analysis

BACKGROUND

Higher neuroticism and lower conscientiousness are risk factors for Alzheimer's disease and related dementias, but the underlying neuropathological correlates remain unclear. Our aim was to examine whether personality traits are associated with amyloid and tau neuropathology in a new sample and meta-analyses.

METHODS

Participants from the BLSA (Baltimore Longitudinal Study of Aging) completed the Revised NEO Personality Inventory and underwent amyloid (¹¹C-labeled Pittsburgh compound B) and tau (¹⁸F-flortaucipir) positron emission tomography.

RESULTS

Among cognitively normal BLSA participants, neuroticism was associated with higher cortical amyloid burden (odds ratio 1.68, 95% CI 1.20-2.34), and conscientiousness was associated with lower cortical amyloid burden (odds ratio 0.61, 95% CI 0.44-0.86). These associations remained significant after accounting for age, sex, education, depressive symptoms, hippocampal volume, and APOE ε4. Similar associations were found with tau in the entorhinal cortex. Random-effects meta-analyses of 12 studies found that higher neuroticism (N = 3015, r = 0.07, p = .008) and lower conscientiousness (N = 2990, r = -0.11, p < .001) were associated with more amyloid deposition. Meta-analyses of 8 studies found that higher neuroticism (N = 2231, r = 0.15, p < .001) and lower conscientiousness (N = 2206, r = -0.14, p < .001) were associated with more tau pathology. The associations were moderated by cognitive status, with stronger effects in cognitively normal compared with heterogeneous samples, suggesting that the associations between personality and proteopathies are not phenomena that emerge with neuropsychiatric clinical symptoms.

CONCLUSIONS

By aggregating results across samples, this study advances knowledge on the association between personality and neuropathology. Neuroticism and conscientiousness may contribute to resistance against amyloid and tau neuropathology.

Personality traits are consistently associated with blood mitochondrial DNA copy number estimated from genome sequences in two genetic cohort studies

Background

Mitochondrial DNA copy number (mtDNAcn) in tissues and blood can be altered in conditions like diabetes and major depression and may play a role in aging and longevity. However, little is known about the association between mtDNAcn and personality traits linked to emotional states, metabolic health, and longevity. This study tests the hypothesis that blood mtDNAcn is related to personality traits and mediates the association between personality and mortality.

Methods

We assessed the big five personality domains and facets using the Revised NEO Personality Inventory (NEO-PI-R), assessed depressive symptoms with the Center for Epidemiologic Studies Depression Scale (CES-D), estimated mtDNAcn levels from whole-genome sequencing, and tracked mortality in participants from the Baltimore Longitudinal Study of Aging. Results were replicated in the SardiNIA Project.

Results

We found that mtDNAcn was negatively associated with the Neuroticism domain and its facets and positively associated with facets from the other four domains. The direction and size of the effects were replicated in the SardiNIA cohort and were robust to adjustment for potential confounders in both samples. Consistent with the Neuroticism finding, higher depressive symptoms were associated with lower mtDNAcn. Finally, mtDNAcn mediated the association between personality and mortality risk.

Conclusions

To our knowledge, this is the first study to show a replicable association between mtDNAcn and personality. Furthermore, the results support our hypothesis that mtDNAcn is a biomarker of the biological process that explains part of the association between personality and mortality.

Funding

Support for this work was provided by the Intramural Research Program of the National Institute on Aging (Z01-AG000693, Z01-AG000970, and Z01-AG000949) and the National Institute of Neurological Disorders and Stroke of the National Institutes of Health. AT was also supported by the National Institute on Aging of the National Institutes of Health Grant R01AG068093.

Vital personality scores and healthy aging: Life-course associations and familial transmission

OBJECTIVES

Personality traits are linked with healthy aging, but it is not clear how these associations come to manifest across the life-course and across generations. To study this question, we tested a series of hypotheses about (a) personality-trait prediction of markers of healthy aging across the life-course, (b) developmental origins, stability and change of links between personality and healthy aging across time, and (c) intergenerational transmission of links between personality and healthy aging. For our analyses we used a measure that aggregates the contributions of Big 5 personality traits to healthy aging: a "vital personality" score.

METHODS

Data came from two population-based longitudinal cohort studies, one based in New Zealand and the other in the UK, comprising over 6000 study members across two generations, and spanning an age range from birth to late life.

RESULTS

Our analyses revealed three main findings: first, individuals with higher vital personality scores engaged in fewer health-risk behaviors, aged slower, and lived longer. Second, individuals' vital personality scores were preceded by differences in early-life temperament and were relatively stable across adulthood, but also increased from young adulthood to midlife. Third, individuals with higher vital personality scores had children with similarly vital partners, promoted healthier behaviors in their children, and had children who grew up to have more vital personality scores themselves, for genetic and environmental reasons.

CONCLUSION

Our study shows how the health benefits associated with personality accrue throughout the life-course and across generations.

The relationship between personality disorder, depression and eating disorder with treatment adherence in patients with type 2 diabetes; a cross-sectional study in diabetic patients in Iran

Purpose

Adherence to treatment is of great importance in patients with diabetes mellitus due to its necessity and benefits. The purpose of this study was to evaluate the relationship between personality disorder, depression and eating disorder with appropriate treatment acceptance and follow-up in patients with type 2 diabetes.

Methods

This cross-sectional study was performed in Imam Ali Medical Education Center in Karaj city of Alborz province of Iran. A total of 1320 patients were evaluated and were screened according to the inclusion criteria, including type 2 diabetes and those over 18 years of age. Finally, considering the exclusion criteria, 600 patients with type 2 diabetes were included in the study. Patients were divided into 4 groups. 150 patients with type 2 diabetes in the control group, 150 patients with type 2 diabetes with major depressive disorder, 150 patients with type 2 diabetes with personality disorder and 150 patients with type 2 diabetes and eating disorder were studied. Questionnaires used in the study included Hamilton Depression Rating Scale(HAM-D) for depression, Minnesota Multiphasic Personality Inventory II (MMPI II) questionnaire for personality disorders and Eating Disorder Diagnostic Scale(EDDS) for eating disorder. The Murisky questionnaire also assessed adherence to treatment in patients, which included 8 questions. Scores measure the degree of adherence to treatment.

Results

600 patients with type 2 diabetes were studied. Patients were divided into 4 groups (each group consisting of 150 patients) of control, depression, personality disorder and eating disorder. Mean age, sex, marital status and duration of diabetes were not significantly different in the study groups (P > 0.05). The mean Murisky score in patients with depression and personality disorder was significantly lower than the control group (P < 0.05) but the mean Murisky score in patients with eating disorder was not significantly different (P > 0.05). Patients with depression, paranoid, schizotypal, antisocial, borderline, avoidant and dependent personality disorder had less adherent to treatment than the control group.

Conclusions

Early psychiatric evaluation of patients with diabetes and identification of possible disorders can help improve diabetes control.

Personality and health literacy among community-dwelling older adults living in Japan

BACKGROUND

Previous studies have demonstrated that health behaviours may be one of the major mechanisms underlying the relationship between personality and health outcomes. Such health behaviours may be established by consciousness toward one's health that include health literacy. Thus, this study aimed to explore the relationship between health literacy and its correlates, including personality, among community-dwelling older adults.

METHODS

This was a cross-sectional study with 683 older individuals (aged 60-84 years; 326 men and 357 women). A questionnaire was used to assess health literacy, personality, socioeconomic status, health status, and lifestyles. Health literacy was measured using the Communicative and Critical Health Literacy Scale, which is a self-report questionnaire comprising five items assessing degrees of health literacy. The Big Five personality traits were measured using the Japanese version of the Ten-Item Personality Inventory. Other variables were measured as factors associated with health literacy, including age, gender, education, subjective economic status, social isolation, chronic diseases, functional capacity, smoking and drinking.

RESULTS

Multiple regression analysis showed that education (β = 0.10), subjective economic status (β = -0.09), social isolation (β = -0.08), functional dependence (β = -0.22), neuroticism, (β = -0.08), extraversion (β = 0.10), openness (β = 0.17), and conscientiousness (β = 0.09) were independently and significantly associated with health literacy (coefficient of determination = 0.28).

CONCLUSIONS

This study found significant and independent associations of personality, socioeconomic status, and health status with health literacy. These results may help facilitate the development of efficient strategies to improve health status by promoting health literacy in community-dwelling older adults.

Personality and HbA1c: Findings from six samples

Personality traits are associated with risk of diabetes, but most research to date has relied on participants reported diagnosis rather than objective markers of glycaemia. The present study examined the association between the five major domains of personality (neuroticism, extraversion, openness, agreeableness and conscientiousness) and haemoglobin A1c (HbA1c). Participants (N > 26,000) were individuals aged from 16 to 104 years from six large community samples from the US, Europe, and Japan who had data on personality, demographic factors, body mass index (BMI), physical activity, and HbA1c. Of the five factors, only higher conscientiousness was related consistently to lower HbA1c level across most samples and in the meta-analysis. Conscientiousness was also related to lower risk of HbA1c ≥6.5 % (OR = .85, 95 %CI = 0.80-0.90). BMI and physical activity partially mediated the link between conscientiousness and HbA1c. There were not consistent associations for the other four traits across the six samples and no consistent associations between personality and likelihood of undiagnosed diabetes. The present study found replicable associations between conscientiousness and HbA1c in adulthood. Assessment of conscientiousness may improve the identification of individuals at risk of diabetes and guide personalized interventions for regulation of HbA1c level.

Personality, disability-free life years, and life expectancy: Individual participant meta-analysis of 131,195 individuals from 10 cohort studies

OBJECTIVE

We examined how personality traits of the Five Factor Model were related to years of healthy life years lost (mortality and disability) for individuals and the population.

METHOD

Participants were 131,195 individuals from 10 cohort studies from Australia, Germany, the United Kingdom, and the United States (n = 43,935 from seven cohort studies for the longitudinal analysis of disability, assessed using scales of Activities of Daily Living).

RESULTS

Lower Conscientiousness was associated with higher mortality and disability risk, but only when Conscientiousness was below its median level. If the excess risk associated with low Conscientiousness had been absent, population life expectancy would have been 1.3 years longer and disability-free life 1.0 years longer. Lower emotional stability was related to shorter life expectancy, but only among those in the lowest 15% of the distribution, and disability throughout the distribution: if the excess risk associated with low emotional stability had been absent, population life expectancy would have been 0.4 years longer and disability-free life 2.4 years longer.

CONCLUSIONS

Personality traits of low Conscientiousness and low emotional stability are associated with reduced healthy life expectancy of individuals and population.

Neuroticism, conscientiousness, and in vivo Alzheimer pathologies measured by amyloid PET and MRI

AIM

It has been suggested that personality traits, particularly neuroticism and conscientiousness, are risk factors for Alzheimer's disease (AD) and related cognitive decline. However, the underlying pathological links between personality traits and AD-related cognitive impairments remain unclear. Thus, the present study investigated associations of neuroticism and conscientiousness with in vivo cerebral amyloid-beta (Aβ) burden, AD-signature regional neurodegeneration, and white matter hyperintensities (WMH) in non-demented middle- and old-aged adults.

METHODS

A total of 397 non-demented participants underwent comprehensive clinical and neuropsychological assessments, ¹¹ C-labeled Pittsburgh Compound B positron emission tomography, and magnetic resonance imaging. Additionally, the NEO Five-Factor Inventory was administered to both the participants and their informants to measure neuroticism and conscientiousness.

RESULTS

Neither neuroticism nor conscientiousness was associated with cerebral Aβ deposition or WMH. In contrast, higher neuroticism and lower conscientiousness, reported by informants in particular, were significantly associated with reduced AD-signature region cortical thickness. In regards to the direct and indirect effect of each personality on AD-signature region cortical thickness, only the direct effects were found, whereas indirect effects via Aβ deposition or WMH were not.

CONCLUSION

The present findings suggest that amyloid-independent regional neurodegeneration might underlie relations of neuroticism and conscientiousness with AD.

Trajectories of Big Five Personality Traits: A Coordinated Analysis of 16 Longitudinal Samples

This study assessed change in self-reported Big Five personality traits. We conducted a coordinated integrative data analysis using data from 16 longitudinal samples, comprising a total sample of over 60 000 participants. We coordinated models across multiple datasets and fit identical multi-level growth models to assess and compare the extent of trait change over time. Quadratic change was assessed in a subset of samples with four or more measurement occasions. Across studies, the linear trajectory models revealed declines in conscientiousness, extraversion, and openness. Non-linear models suggested late-life increases in neuroticism. Meta-analytic summaries indicated that the fixed effects of personality change are somewhat heterogeneous and that the variability in trait change is partially explained by sample age, country of origin, and personality measurement method. We also found mixed evidence for predictors of change, specifically for sex and baseline age. This study demonstrates the importance of coordinated conceptual replications for accelerating the accumulation of robust and reliable findings in the lifespan developmental psychological sciences.

Five Factor Model Personality Traits and Subjective Cognitive Failures

Momentary lapses in memory, perception, or action, known as cognitive failures, are relatively common. These lapses may reflect, in part, aspects of psychological functioning, such as personality traits. The present research addresses how Five Factor Model personality traits and facets are associated with cognitive failures, and whether these associations are accounted for by depressed affect. Participants (N=5,133; 50% female) who ranged in age from 18 to 91 completed an online survey that assessed their personality traits, cognitive failures, and depressed affect. Higher neuroticism was associated with more cognitive failures, whereas Conscientiousness and Agreeableness were associated with fewer failures, controlling for sociodemographic characteristics. Controlling for depressed affect reduced the associations in most cases by about 50%, but most relations were still apparent. Facet-level analyses provided a more detailed picture of how the traits are associated with cognitive failures. Subjective perceptions of lapses in cognition are associated with basic personality traits and may reflect, in part, processes related to those traits beyond depressed affect.

Personality traits and risk of lifetime asthma diagnosis

OBJECTIVE

Traits defined by the Five-Factor Model (FFM) of personality have been linked to physical health, leading to treatment implications and psychophysiological conceptualizations. Previous studies have reported a consistent link between neuroticism and asthma. This study aims to reinforce this finding and further its scope by looking at all five personality traits and lifetime asthma diagnosis.

METHODS

The current study examined associations between personality traits and lifetime asthma diagnosis in a sample of 3993 participants and, for the purposes of replication, a second sample of 1692 participant siblings. Personality was measured at a single time point in adulthood (mean age: 53 years), while asthma diagnosis by a medical professional was self-reported across three time points over a range of 54 years. A binary logistic regression was performed to examine the association between FFM personality traits and the likelihood of having endorsed asthma at any time point.

RESULTS

Higher scores in the traits of neuroticism (β = 0.024, p = .03, OR = 1.025) and openness (β = 0.041, p < .001, OR = 1.042) were associated with increased risk of lifetime asthma diagnosis, while the trait of conscientiousness (β = -0.034, p = .009, OR = 0.967) was associated with decreased risk of lifetime asthma diagnosis. The associations with neuroticism and openness were replicated in the sibling sample.

CONCLUSION

These findings suggest that research into certain personality traits might help us better understand psychophysiological connections. Neuroticism, openness, and conscientiousness might be salient factors in developing asthma education and treatment.

Prevalence of the Effects of Anxiety and Depression on People with Type 2 Diabetes Mellitus: An Analysis of Health Policy Studies in Improving the Quality of Life of Poor Families in the Urban Areas of West Lombok, Indonesia

BACKGROUND

To explore the tendency of the effects of anxiety and depression that occur in type 2 diabetes patients, especially poor patients who live in the urban areas with poor economic conditions, who do not have health access from the government, and live away from the hospitals.

METHODS

It is a cross-sectional study which aimed to determine the number of patients who experienced anxiety and depression problems due to the declining health conditions caused by diabetes. A sample size of 98 diabetics experiencing anxiety and depression when the treatment was carried out was included. The study design included a qualitative study with in-depth interviews with respondents who were at risk of diabetes, as well as to determine the level of anxiety and depression that occurred when medical care was provided and the feelings experienced by the respondents after the completion of treatment.

RESULTS

Diabetic patients are generally unaware that their illness is a chronic disease that takes a long time to treat. When the patients are sick, most of them do not immediately go to the hospital or a specialist to get their health examination and treatment, because the hospital is far from the patients' residence. Furthermore, some patients still use traditional medicine and non-medical treatment, so when the patients with critical conditions are taken to the hospital, they already have chronic diabetes.

CONCLUSION

The lack of access to health for chronic patients with poor economic conditions who live far from the hospitals and the scarcity of medical staff to carry out treatment of chronic diseases such as diabetes for poor patients in urban areas certainly have an impact on increasing the number of patients with chronic diseases. Therefore, the government is expected to be able to provide easy health policies to remote rural communities in order to achieve optimal community welfare and health.

Personality Traits Do Not Have Influence on Glycemic Control in Outpatients with Type 2 Diabetes Mellitus

OBJECTIVE

Glycemic control varies based on lifestyle factors and stress coping mechanisms, which are influenced by personality. The psychological factors associated with glycemic control have not yet been established in patients with type 2 diabetes mellitus (T2DM). The relationship between a 5-factor model of personality and glycemic control was evaluated in individuals with T2DM.

METHODS

The subjects were 503 Japanese outpatients with T2DM. Glycated hemoglobin A1c (HbA1c) levels, depressive status, insomnia and personality traits were assessed. Lifestyle factors of the patients, such as habitual alcohol consumption and smoking, were also included in the analyses.

RESULTS

Because the influence of insulin therapy on HbA1c is so strong, we stratified the patients according to insulin use. Simple regression analysis showed a significant correlation between HbA1c and neuroticism in patients who did not use insulin. After adjustment for confounders, multiple regression analyses revealed that none of the personality factors, including neuroticism, were found to be associated with HbA1c.

CONCLUSION

These findings suggest that personality traits do not have a large impact on glycemic control. Further studies are required to confirm the relationships between psychological factors and glycemic control using a longitudinal study design.

Personality traits predict dietary habits in middle-to-older adults

Personality traits are consistently associated with health behaviors, but little research has examined the role of personality on eating habits among middle-to-older adults. The current study (n = 665) examined the associations between traits and dietary habits and whether healthy eating predicted health at age 60, with the Hawaii Personality and Health Cohort. Eating healthy foods was associated with higher agreeableness, conscientiousness, emotional stability, and openness, and predicted better self-rated health and lower BMI. Eating unhealthy foods was associated with lower agreeableness, conscientiousness, emotional stability, and openness, and predicted lower self-rated health. Results were not moderated by SES.

The influence of personality on trajectories of distress, health and functioning in mild-to-moderately depressed adults with type 2 diabetes

Identification of mental health risk is important for optimising diabetes care in type 2 diabetes mellitus (T2DM). Personality is linked to diabetes health and may assist detection of individuals with T2DM most at risk of chronic mental health difficulties. This study examined the moderator effect of personality factors on changes in psychological distress and functioning in adults with T2DM and mild-to-moderate depressive symptoms across a 12-month period. Data were obtained from participants in a randomised controlled trial of adults with T2DM.  Participants completed measures of depression (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder-7), general functioning (Work and Social Adjustment Scale), diabetes distress (Diabetes Distress Scale), and diabetes self-management (Self-Management Profile for Type 2 Diabetes) at baseline, 3-, 6- and 12-months. Glycaemic control (HbA1c) was measured at baseline, 6- and 12-months. Two hundred trial completers agreed to complete a personality inventory (Big Five Inventory). Low neuroticism was linked with reduced depression, anxiety, functional impairment and diabetes distress over the year. High extraversion was associated with decreased anxiety and functional impairment. High conscientiousness was linked to increased healthy eating. No personality trait moderated HbA1c levels. Personality screening may help identify mental health risk and guide medical carer approach in T2DM patients.

Differential associations of depression-related phenotypes with cardiometabolic risks: Polygenic analyses and exploring shared genetic variants and pathways

BACKGROUND

Numerous studies have suggested associations between depression and cardiometabolic (CM) diseases. However, little is known about the mechanism underlying this comorbidity, and whether the relationship differs by depression subtypes.

METHODS

Using polygenic risk scores (PRS) and linkage disequilibrium (LD) score regression, we investigated the genetic overlap of various depression-related phenotypes with a comprehensive panel of 20 CM traits. GWAS results for major depressive disorder (MDD) were taken from the PGC and CONVERGE studies, with the latter focusing on severe melancholic depression. GWAS results on general depressive symptoms (DS) and neuroticism were also included. We identified the shared genetic variants and inferred enriched pathways. We also looked for drugs over-represented among the top-shared genes, with an aim to finding repositioning opportunities for comorbidities.

RESULTS

We found significant genetic overlap between MDD, DS, and neuroticism with cardiometabolic traits. In general, positive polygenic associations with CM abnormalities were observed except for MDD-CONVERGE. Counterintuitively, PRS representing severe melancholic depression was associated with reduced CM risks. Enrichment analyses of shared SNPs revealed many interesting pathways such as those related to inflammation that underlie the comorbidity of depressive and CM traits. Using a gene-set analysis approach, we also revealed several repositioning candidates with literature support (e.g., bupropion).

CONCLUSIONS

Our study highlights shared genetic bases of depression with CM traits, and suggests the associations vary by depression subtypes, which may have implications in targeted prevention of cardiovascular events for patients. Identification of shared genetic factors may also guide drug discovery for the comorbidities.

Alcohol use and personality trait change: pooled analysis of six cohort studies

BACKGROUND

Personality has been associated with alcohol use, but less is known about how alcohol use may influence long-term personality trait change.

METHODS

The present study examines associations between alcohol use and change in the five major personality traits across two measurement occasions (mean follow-up of 5.6 years). A total of 39 722 participants (54% women) were pooled from six cohort studies for an individual-participant meta-analysis. Alcohol use was measured as (1) average alcohol consumption, (2) frequency of binge drinking, (3) symptoms of alcohol use disorder, and (4) a global indicator of risky alcohol use. Changes in the five major personality traits (extraversion, emotional stability, agreeableness, conscientiousness, and openness to experience) were used as outcomes.

RESULTS

Risky alcohol use was associated with increasing extraversion [0.25 T-scores over the mean follow-up of 5.6 years; 95% confidence interval (CI) 0.07-0.44] and decreasing emotional stability (-0.28; 95% CI -0.48 to -0.08), agreeableness (-0.67; 95% CI -0.87 to -0.36), and conscientiousness (-0.58; 95% CI -0.79 to -0.38). Except the association between alcohol use and extraversion, these associations were consistent across cohort studies and across different measures of alcohol use.

CONCLUSIONS

These findings suggest that alcohol use is associated with personality trait changes in adulthood.

Analysis of Cardiovascular Fitness, Sleep Quality, Depression, Fatigue, and Quality of Life among Individuals with Respect to the Glycated Hemoglobin Level in Type 2 Diabetes Mellitus

<b><i>Background:</i></b> Diabetes as a metabolic disorder can affect the various systems of the body, resulting in a decrease in cardiovascular fitness, sleep quality, and life quality that can lead to depression and fatigue. <b><i>Aim:</i></b> We analyzed cardiovascular fitness, sleep quality, depression, fatigue, and quality of life among individuals with a glycated hemoglobin (HBA1C) level &#x3e;6.5% and ≤6.5%, as well as the relationship among glycated hemoglobin, maximal oxygen consumption (VO₂max), obesity, sleep quality, depression, and duration of diabetes. <b><i>Method:</i></b> HBA1C (mean: 5.90 ± 0.93%) was studied in a total of 70 subjects (mean age: 62.37 ± 7.5 years). The 2 study groups were as follows: group A, HBA1C &#x3e;6.5%, and group B, HBA1C ≤6.5%. BMI, VO₂max, quality of sleep and life, depression, and fatigue were assessed in both groups. <b><i>Results:</i></b> There was a statistically significant difference between the groups at a significance level of <i>p</i> &#x3c; 0.001. Group A had a lower cardiovascular fitness, a poor sleep quality, and increased depression compared to group B. A statistically significant negative linear correlation was found between VO₂max and glycated hemoglobin, and a significant positive linear correlation was found between glycated hemoglobin and duration of diabetes, poor quality of sleep, and depression for all subjects, which was insignificant in the groups. <b><i>Conclusions:</i></b> A long duration of diabetes and an increased glycemic status may influence cardiovascular fitness, sleep quality, and life quality, leading to depression and fatigue.

The Life Skills of Older Americans: Association with Economic, Psychological, Social, and Health Outcomes

Studies of children and adolescents indicate that success in life is determined in part by attributes such as conscientiousness, emotional stability and sense of control, independently of childhood socioeconomic status and cognitive ability. Less is known about the role of these characteristics at older ages. This study investigated the relationship of five life skills - conscientiousness, emotional stability, persistence, optimism and sense of control - with a range of outcomes in 8,843 participants (mean age 72.57 years) in the Health and Retirement Study, a representative study of older Americans. More life skills were associated with greater wealth and income, better emotional wellbeing, stronger social relationships, less loneliness, better health, fewer chronic illnesses and impaired activities of daily living, better mobility and less obesity, after controlling for childhood socioeconomic status and current cognitive ability. Longitudinally, more life skills predicted emotional wellbeing, less loneliness and more prosocial behavior, better health and mobility over a 4 year period. Associations were independent of gender, ethnicity, family background, education and cognitive ability. The number of attributes was important rather than any single life skill. Life skills continue to matter at advanced ages, and fostering these characteristics in older adults may pay dividends in terms of later life health and wellbeing.

White matter tract network disruption explains reduced conscientiousness in multiple sclerosis

Quantifying white matter (WM) tract disruption in people with multiple sclerosis (PwMS) provides a novel means for investigating the relationship between defective network connectivity and clinical markers. PwMS exhibit perturbations in personality, where decreased Conscientiousness is particularly prominent. This trait deficit influences disease trajectory and functional outcomes such as work capacity. We aimed to identify patterns of WM tract disruption related to decreased Conscientiousness in PwMS. Personality assessment and brain MRI were obtained in 133 PwMS and 49 age- and sex-matched healthy controls (HC). Lesion maps were applied to determine the severity of WM tract disruption between pairs of gray matter regions. Next, the Network-Based-Statistics tool was applied to identify structural networks whose disruption negatively correlates with Conscientiousness. Finally, to determine whether these networks explain unique variance above conventional MRI measures and cognition, regression models were applied controlling for age, sex, brain volume, T2-lesion volume, and cognition. Relative to HCs, PwMS exhibited lower Conscientiousness and slowed cognitive processing speed (p = .025, p = .006). Lower Conscientiousness in PwMS was significantly associated with WM tract disruption between frontal, frontal-parietal, and frontal-cingulate pathways in the left (p = .02) and right (p = .01) hemisphere. The mean disruption of these pathways explained unique additive variance in Conscientiousness, after accounting for conventional MRI markers of pathology and cognition (ΔR²  = .049, p = .029). Damage to WM tracts between frontal, frontal-parietal, and frontal-cingulate cortical regions is significantly correlated with reduced Conscientiousness in PwMS. Tract disruption within these networks explains decreased Conscientiousness observed in PwMS as compared with HCs.

Investigating the Early Life Determinants of Type-II Diabetes Using a Project Talent-Medicare Linked Data-set

The increasing prevalence of Type II Diabetes (T2D) presents a serious health and financial public crisis. Our study examines the hypothesis that adolescents' perceptions of economic insecurity, along with absolute and relative socioeconomic status (SES), can contribute to T2D prevalence later in life. Project Talent (PT) Survey data, collected on high school students in 1960, have been linked to Medicare records from 2012, presenting a unique opportunity to examine measures gathered in adolescence and T2D prevalence later-in-life among a large, national, and diverse sample (n=88,849). Our results provide compelling evidence that real, perceived, and relative SES in adolescence have persistent impacts on later-in-life diabetes risk, even when controlling for possible confounders such as cognitive ability, conscientiousness, and early-adulthood educational attainment.

Risk factors for type 2 diabetes mellitus: An exposure-wide umbrella review of meta-analyses

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a global epidemic associated with increased health expenditure, and low quality of life. Many non-genetic risk factors have been suggested, but their overall epidemiological credibility has not been assessed.

METHODS

We searched PubMed to capture all meta-analyses and Mendelian randomization studies for risk factors of T2DM. For each association, we estimated the summary effect size, its 95% confidence and prediction interval, and the I2 metric. We examined the presence of small-study effects and excess significance bias. We assessed the epidemiological credibility through a set of predefined criteria.

RESULTS

We captured 86 eligible papers (142 associations) covering a wide range of biomarkers, medical conditions, and dietary, lifestyle, environmental and psychosocial factors. Adiposity, low hip circumference, serum biomarkers (increased level of alanine aminotransferase, gamma-glutamyl transferase, uric acid and C-reactive protein, and decreased level of adiponectin and vitamin D), an unhealthy dietary pattern (increased consumption of processed meat and sugar-sweetened beverages, decreased intake of whole grains, coffee and heme iron, and low adherence to a healthy dietary pattern), low level of education and conscientiousness, decreased physical activity, high sedentary time and duration of television watching, low alcohol drinking, smoking, air pollution, and some medical conditions (high systolic blood pressure, late menarche age, gestational diabetes, metabolic syndrome, preterm birth) presented robust evidence for increased risk of T2DM.

CONCLUSIONS

A healthy lifestyle pattern could lead to decreased risk for T2DM. Future randomized clinical trials should focus on identifying efficient strategies to modify harmful daily habits and predisposing dietary patterns.

Personality and Risk of Frailty: the English Longitudinal Study of Ageing

Background

There is evidence that the personality traits conscientiousness, extraversion and neuroticism are associated with health behaviours and with risk of various health outcomes. We hypothesised that people who are lower in conscientiousness or extraversion or higher in neuroticism may be at greater risk of frailty in later life.

Methods

We used general linear models to examine the prospective relation between personality, assessed using the Midlife Development Inventory, and change in frailty, modelled by a frailty index, in 5314 men and women aged 60 to over 90 years from the English Longitudinal Study of Ageing.

Results

Men and women with higher levels of neuroticism or lower levels of extraversion or conscientiousness had an increased frailty index score at follow-up. After adjustment for potential confounding or mediating variables, including frailty index score at baseline, the frailty index score at follow-up—which potentially ranges from 0 to 1—was higher by 0.035 (95 % confidence interval 0.018, 0.052) for a standard deviation increase in neuroticism and lower by 0.061 (0.031, 0.091) or 0.045 (0.020, 0.071) for a standard deviation increase in extraversion or conscientiousness, respectively. There was some evidence that the association between extraversion and frailty may be due to reverse causation whereby poorer health affected responses to items in the personality inventory.

Conclusions

Higher levels of neuroticism or lower levels of conscientiousness or extraversion may be risk factors for the onset or progression of frailty. Future studies need to replicate these observations in other populations and explore the mechanisms underlying these associations.

Conscientiousness, hair cortisol concentration, and health behaviour in older men and women

Conscientious is associated with greater longevity and other favourable health outcomes, but the processes underlying these links are poorly understood. Health behaviours such as physical activity and avoidance of smoking and excessive alcohol consumption may contribute, but direct associations with neuroendocrine and inflammatory processes may also be relevant. We tested the associations between conscientiousness and hair cortisol concentration in 2318 older men and women (mean age 66.2 years) from the English Longitudinal Study of Ageing. Conscientiousness was positively associated with physical activity and fruit and vegetable consumption, and negatively related to alcohol intake, sedentary behaviour, body mass index and depressive symptoms (all p<0.001). We found an inverse association between conscientiousness and hair cortisol concentration that was independent of age, sex, education and wealth (β=-0.053, p=0.012), and the relationship remained significant with additional adjustment for health behaviour and depressive symptoms (β=-0.048, p=0.025). The observation that greater conscientiousness was correlated with lower hair cortisol indicates that this trait might impact central nervous regulation of hypothalamic-pituitary-adrenocortical function, with effects that are possibly advantageous for health.

Personality traits and risk of cognitive impairment and dementia

We investigated the association between five factor model personality traits (neuroticism, extraversion, openness, agreeableness, and conscientiousness) and risk of dementia, cognitive impairment not dementia (CIND), and conversion from CIND to dementia in a large national cohort. Participants from the Health and Retirement Study (N > 10,000) completed a personality scale in 2006-2008 and their cognitive status was tracked for up to 8 years using the modified Telephone Interview for Cognitive Status (TICSm). Adjusting for age, sex, education, race, and ethnicity, lower conscientiousness and agreeableness and higher neuroticism were independently associated with increased risk of dementia. These associations remained significant after adjusting for other risk factors for dementia, including income, wealth, smoking, physical inactivity, obesity, diabetes, hypertension, and blood biomarkers. These associations were not modified by age, sex, race, ethnicity, and education, suggesting that the associations of personality with risk of dementia were similar across demographic groups. Neuroticism and conscientiousness were also associated with risk of CIND. Low conscientiousness predicted conversion from CIND to dementia. Using brief assessments of personality and cognition, we found robust evidence that personality is associated with risk of cognitive impairment and dementia in a large national sample.

The five-factor model of personality and self-reported versus biomarker diabetic control

Five-factor personality was examined as an element of self-report diabetic control accuracy versus biomarker control (HbA1c) for 1474 diabetics in the 2006 and 2008 Health and Retirement Study. Correlations of extraversion and self-reported control ( r = −.06, p < .01), and extraversion and HbA1c ( r = .03, non-significant), were significantly different ( t = 2.87, p < .01). Correlations of openness and self-reported control ( r = −.05, p < .05), and openness and HbA1c ( r = .01, non-significant), were significantly different ( t = 1.91, p < .05). Associations were found between self-reported control and conscientiousness ( r = −.05, p < .05), neuroticism ( r = .04, p < .05), and openness ( r = −.05, p < .05). Neuroticism was associated with self-reports that diabetes was worse ( r = .07, p < .01). Other correlations and comparisons were non-significant.

Towards More Rigorous Personality Trait–Outcome Research

Much of personality research attempts to identify causal links between personality traits and various types of outcomes. I argue that causal interpretations require traits to be seen as existentially and holistically real and the associations to be independent of specific ways of operationalizing the traits. Among other things, this means that, to the extents that causality is to be ascribed to such holistic traits, items and facets of those traits should be similarly associated with specific outcomes, except for variability in the degrees to which they reflect the traits (i.e. factor loadings). I argue that, before drawing causal inferences about personality trait–outcome associations, the presence of this condition should be routinely tested by, for example, systematically comparing the outcome associations of individual items or facets, or sampling different indicators for measuring the same purported traits. Existing evidence suggests that observed associations between personality traits and outcomes at least sometimes depend on which particular items or facets have been included in trait operationalizations, calling trait–level causal interpretations into question. However, this has rarely been considered in the literature. I argue that when outcome associations are specific to facets, they should not be generalized to traits. Furthermore, when the associations are specific to particular items, they should not even be generalized to facets. Copyright © 2016 European Association of Personality Psychology

Pleiotropy between neuroticism and physical and mental health: findings from 108 038 men and women in UK Biobank

People with higher levels of neuroticism have an increased risk of several types of mental disorder. Higher neuroticism has also been associated, less consistently, with increased risk of various physical health outcomes. We hypothesised that these associations may, in part, be due to shared genetic influences. We tested for pleiotropy between neuroticism and 17 mental and physical diseases or health traits using linkage disequilibrium regression and polygenic profile scoring. Genetic correlations were derived between neuroticism scores in 108 038 people in the UK Biobank and health-related measures from 14 large genome-wide association studies (GWASs). Summary information for the 17 GWASs was used to create polygenic risk scores for the health-related measures in the UK Biobank participants. Associations between the health-related polygenic scores and neuroticism were examined using regression, adjusting for age, sex, genotyping batch, genotyping array, assessment centre and population stratification. Genetic correlations were identified between neuroticism and anorexia nervosa (rg=0.17), major depressive disorder (rg=0.66) and schizophrenia (rg=0.21). Polygenic risk for several health-related measures were associated with neuroticism, in a positive direction in the case of bipolar disorder, borderline personality, major depressive disorder, negative affect, neuroticism (Genetics of Personality Consortium), schizophrenia, coronary artery disease, and smoking (β between 0.009-0.043), and in a negative direction in the case of body mass index (β=-0.0095). A high level of pleiotropy exists between neuroticism and some measures of mental and physical health, particularly major depressive disorder and schizophrenia.

Personality and smoking: individual-participant meta-analysis of nine cohort studies

AIMS

To investigate cross-sectional and longitudinal associations between personality and smoking, and test whether socio-demographic factors modify these associations.

DESIGN

Cross-sectional and longitudinal individual-participant meta-analysis.

SETTING

Nine cohort studies from Australia, Germany, the United Kingdom and the United States.

PARTICIPANTS

A total of 79 757 men and women (mean age = 50.8 years).

MEASUREMENTS

Personality traits of the five-factor model (extraversion, neuroticism, agreeableness, conscientiousness and openness to experience) were used as exposures. Outcomes were current smoking status (current smoker, ex-smoker and never smoker), smoking initiation, smoking relapse and smoking cessation. Associations between personality and smoking were modelled using logistic and multinomial logistic regression, and study-specific findings were combined using random-effect meta-analysis.

FINDINGS

Current smoking was associated with higher extraversion [odds ratio per 1 standard deviation increase in the score: 1.16; 95% confidence interval (CI) = 1.08-1.24], higher neuroticism (1.19; 95% CI = 1.13-1.26) and lower conscientiousness (95% CI = 0.88; 0.83-0.94). Among non-smokers, smoking initiation during the follow-up period was predicted prospectively by higher extraversion (1.22; 95% CI = 1.04-1.43) and lower conscientiousness (0.80; 95% CI = 0.68-0.93), whereas higher neuroticism (1.16; 95% CI = 1.04-1.30) predicted smoking relapse among ex-smokers. Among smokers, smoking cessation was negatively associated with neuroticism (0.91; 95% CI = 0.87-0.96). Socio-demographic variables did not appear to modify the associations between personality and smoking.

CONCLUSIONS

Adult smokers have higher extraversion, higher neuroticism and lower conscientiousness personality scores than non-smokers. Initiation into smoking is associated positively with higher extraversion and lower conscientiousness, while relapse to smoking among ex-smokers is associated with higher neuroticism.