Associations of Personality Traits With Chronic Low-Grade Inflammation in a Swiss Community Sample

Correlations between personality traits, personality disorders, and immunometabolic markers

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

Personality and Cognition: The Mediating Role of Inflammatory Markers

OBJECTIVES

Five-Factor Model personality traits are associated consistently with cognition. Inflammation has been hypothesized as a biological pathway in this association, but this assumption has yet to be tested. The present study tested inflammatory markers as mediators between personality traits and cognition.

METHODS

Participants were from the Health and Retirement Study (HRS; N = 4,364; 60% women; mean age = 64.48 years, standard deviation = 8.79). Personality traits and demographic factors were assessed in 2010/2012. Data on inflammatory markers (high-sensitivity C-reactive protein [hsCRP], interleukin-6 [IL-6], soluble tumor necrosis factor 1 (sTNFR1), interleukin-10 [IL-10], interleukin-1 receptor antagonist [IL-1Ra], and transforming growth factor [TGF]-β1) were obtained in 2016 from the HRS Venuous Blood Study. Cognition was assessed in 2020 using the modified Telephone Interview for Cognitive Status.

RESULTS

Higher neuroticism was related to lower cognition at follow-up, whereas higher extraversion, openness, agreeableness, and conscientiousness were associated with better cognition. Higher extraversion and higher conscientiousness were related to lower hsCRP, IL-6, IL-10, IL-1Ra, and sTNFR1, and higher openness was associated with lower IL-10, IL-1Ra, and sTNFR1 and to higher soluble TGF-β1. Lower sTNFR1 partially mediated the associations between conscientiousness, extraversion, and openness and cognition at follow-up, explaining an estimated 4%-12% of these associations. The mediating role of sTNFR1 persisted when physical activity and depressive symptoms were included as additional mediators.

DISCUSSION

The present study provides new evidence on personality and inflammatory markers. Consistent with the inflammation hypothesis, the sTNFR1 finding supports a potential biological pathway between personality and cognition.

The association between personality and plasma biomarkers of astrogliosis and neuronal injury

Personality traits have been associated with the risk of dementia and Alzheimer's disease neuropathology, including amyloid and tau. This study examines whether personality traits are concurrently related to plasma glial fibrillary acidic protein (GFAP), a marker of astrogliosis, and neurofilament light (NfL), a marker of neuronal injury. Cognitively unimpaired participants from the Baltimore Longitudinal Study on Aging (N = 786; age: 22-95) were assayed for plasma GFAP and NfL and completed the Revised NEO Personality Inventory, which measures 5 domains and 30 facets of personality. Neuroticism (particularly vulnerability to stress, anxiety, and depression) was associated with higher GFAP and NfL. Conscientiousness was associated with lower GFAP. Extraversion (particularly positive emotions, assertiveness, and activity) was related to lower GFAP and NfL. These associations were independent of demographic, behavioral, and health covariates and not moderated by age, sex, or apolipoprotein E genotype. The personality correlates of astrogliosis and neuronal injury tend to be similar, are found in individuals without cognitive impairment, and point to potential neurobiological underpinnings of the association between personality traits and neurodegenerative diseases.

Personality and aging-related immune phenotype

An aging-related immune phenotype (ARIP) has been defined as a decrease in naïve T cells (T_N) relative to the accumulation of memory T cells (T_M). Recent research implicates ARIP measures, such as CD4 +T_N/T_M and CD8 +T_N/T_M ratios, in multimorbidity and mortality. This study examined whether psychological dispositions that assess how people think, feel, and behave are related to CD4 +T_N/T_M and CD8 +T_N/T_M. Participants were adults aged 50-104 years (N = 4798; 58% women, Mean Age= 67.95, SD= 9.56) from the Health and Retirement Study. Data on CD4 +T_N/T_M and CD8 +T_N/T_M were obtained in 2016. Data on personality, demographic factors, and potential clinical (body mass index, disease burden), behavioral (smoking, alcohol, physical activity), psychological (depressive symptoms, stress), and biological (cytomegalovirus IgG antibodies) mediating factors were obtained in 2014/2016. Controlling for demographic factors, higher conscientiousness was related to higher CD4 +T_N/T_M and CD8 +T_N/T_M. To a lesser extent, higher neuroticism and lower extraversion were associated with lower CD4 +T_N/T_M. Physical activity, and to a lesser extent BMI and disease burden, were the most robust mediators between personality and ARIP measures. Cytomegalovirus IgG level mediated the association between conscientiousness and both CD4 +T_N/T_M and CD8 +T_N/T_M. This study provides novel evidence that personality is related to ARIP. Higher conscientiousness and, to a lesser extent, higher extraversion may be protective against age-related immunophenotype change, whereas neuroticism may be a risk factor.

Network analysis of the associations between personality traits, cognitive functioning, and inflammatory markers in elderly individuals without dementia

Introduction

Lower cognitive functioning in old age has been associated with personality traits or systemic inflammatory markers. Associations have also been found between personality traits and inflammatory markers. However, no study has explored the inter-relationships between these three components simultaneously. The present study aims to better understand the inter-relationships among personality traits, inflammatory markers, and cognitive performance in elderly individuals without dementia.

Methods

This study utilizes a network analysis approach, a statistical method that allows visualization of the data's unique pairwise associations. We performed a cross-sectional analysis on 720 elderly individuals without dementia, using data from Colaus|PsyColaus, a population-based study conducted in Lausanne, Switzerland. The Revised NEO Five-Factor Inventory (NEO-FFI-R) was used to assess personality traits, and interleukin (IL)-1β, IL-6, tumor necrosis factor-α (TNF-α), and C-reactive protein (CRP) were used as peripheral inflammatory markers. Cognitive domains were investigated using the Mini-Mental State Examination (MMSE), the Verbal Fluency Test, the Stroop Test, the DO40, and the Free and Cued Selective Reminding (FCSR) test.

Results

Openness was associated with verbal fluency and Agreeableness with immediate free recall. In contrast, no association between inflammatory markers and personality traits or cognition was identified.

Discussion

In elderly individuals without dementia, a high level of Openness or Agreeableness was associated with executive functioning/semantic memory and episodic memory, respectively.

Association of Stroke and Cerebrovascular Pathologies With Scam Susceptibility in Older Adults

Importance

Scam susceptibility is associated with adverse financial and health outcomes, including an increased risk of cognitive decline and dementia. Very little is known about the role of cerebrovascular pathologies with scam susceptibility.

Objective

To examine the association of diverse cerebrovascular pathologies (globally and regionally) with scam susceptibility.

Design, setting, and Participants

This clinical-pathological cohort study included participants from 2 ongoing studies of aging that began enrollment in 1994 and 1997. In 2010, participants were enrolled in the decision-making and behavioral economics substudy and were followed up for a mean (SD) of 3.4 (2.6) years prior to death. From 1365 older persons with clinical evaluations, 69 were excluded for having dementia at baseline. From 538 older persons who died, 408 had annual assessments for scam susceptibility, cardiovascular risk burden, and cognitive function and consented to brain donation for detailed neuropathologic examination. Data were analyzed from June 2021 through September 2022.

Exposures

Neuropathologic examination identified the presence of macroscopic and microscopic infarcts, atherosclerosis, arteriolosclerosis, cerebral amyloid angiopathy, and common neurodegenerative pathologies (Alzheimer disease, limbic-predominant age-related transactive response DNA-binding protein 43 encephalopathy, and Lewy bodies).

Results

There was a total of 408 participants. The mean (SD) age at death was 91 (6.1) years, the mean (SD) amount of education was 15.6 (3.1) years, and 297 (73%) were women. Participants included 4 Latino individuals (1%), 7 non-Latino Black individuals (2%), and 397 non-Latino White individuals (97%). The frequency of participants with macroscopic infarcts was 38% (n = 154), microinfarcts was 40% (n = 163), and moderate to severe vessel disease; specifically, atherosclerosis was 20% (n = 83), arteriolosclerosis was 25% (n = 100), and cerebral amyloid angiopathy was 35% (n = 143). In linear regression models adjusted for demographics and neurodegenerative pathologies, macroscopic infarcts were associated with greater scam susceptibility (estimate [SE], 0.18 [0.07]; P = .009). This association persisted after adjusting for cardiovascular risk burden and global cognition. Regionally, infarcts localized to the frontal, temporal, and occipital lobes and thalamus were associated with greater scam susceptibility. Neither arteriosclerosis, atherosclerosis, cerebral amyloid angiopathy, nor microinfarcts were associated with scam susceptibility.

Conclusions and Relevance

Cerebrovascular pathologies, specifically cerebral infarcts, is linked with greater scam susceptibility in older adults, independent of common neurodegenerative diseases such as Alzheimer disease. Future studies examining in vivo magnetic resonance imaging markers of cerebrovascular pathologies with scam susceptibility and related decision-making outcomes will be important.

Personality Traits and Inflammation in Depressive Disorders

Depression is a psychiatric disorder of heterogeneous etiology. One of the leading theories suggests an inflammatory background to it. It is often found in the scientific literature that certain personality traits, such as high neuroticism, low extroversion and conscientiousness, are being associated with depression. We combined biochemical tests of IL-1 and IL-6 serum levels and scores in the personality test EPQ-R among 50 depressed patients and 37 healthy participants. The results confirmed increased serum levels of IL-1 and IL-6 in a study group when compared to healthy volunteers. Additionally, personality traits (psychoticism and neuroticism) were increased in the depressed group when compared to healthy volunteers. The authors analyzed correlations in both groups. However, only one statistically significant link was observed in IL-6 and K levels (scale associated with the need for social acceptance) in the control group.

Exploring the Links between Personality and Immune Function

Decades of research finds associations between personality traits and health. In recent years, it has become clear that the activities of the immune system play a key role in linking these variables. In the current work, we add to this research by exploring the relationship between Big Five personality traits and (Study 1) polymorphisms known to impact cytokine release and (Study 2) immunological parameters measured in vivo (differential white blood cell counts, plasma proinflammatory cytokine levels) and in vitro (proinflammatory cytokine release by peripheral blood mononuclear cells, Staphylococcus aureus growth in plasma). Results provide insights into potential mechanistic drivers of the link between personality and immune function and the possibility that, in some cases, relationships between personality and immune function may be sex differentiated.

Perfectionistic cognitions, Interleukin-6, and C-Reactive protein: A test of the perfectionism diathesis stress model

Previous research has demonstrated that perfectionism is implicated in poorer health and earlier mortality. However, to our knowledge, research has not yet determined how individual differences in perfectionistic cognitions are related to intermediary health markers such as inflammation. Thus, within the theoretical frameworks of the perfectionism diathesis-stress model (Hewitt and Flett, 1993) and the cognitive theory of perfectionism (Flett et al., 2018; Flett et al., 2016) the aims of our study were to test whether individual differences in perfectionistic cognitions were associated with low-grade inflammation via c-reactive CRP and IL-6 biomarkers and whether these relationships varied as a function perceived stress. The sample included 248 Canadian young adults (52% female, Mage ​= ​22.89, SD ​= ​1.53) who completed surveys assessing key constructs such as perfectionistic cognitions and perceived stress along with providing assessments of body fat percentage and serum samples of IL-6 and CRP. Regression analyses indicated that perfectionistic cognitions were not related to IL-6 under any conditions of stress. However, under high levels of stress perfectionistic cognitions were associated with elevated levels of CRP and these findings held after accounting for the effects of smoking status, body fat percentage, and respondent sex. The present work adds to the growing body of evidence supporting links between personality and inflammation. These findings raise the possibility that experiencing more frequent thoughts centered on the need to be perfect when coupled with higher levels of stress may set the stage for greater vulnerability for chronic inflammation.

•

Perfectionistic cognitions were related to elevated levels of CRP under high levels of perceived stress.

•

Perfectionistic cognitions were not related to CRP under low or moderate levels of perceived stress.

•

Perfectionistic cognitions were not related to IL-6 under any conditions of stress.

Personality matters: relationship between personality characteristics, spirituality, demoralization, and perceived quality of life in a sample of end-of-life cancer patients

PURPOSE

Personality could be an interesting dimension to explore in end-of-life cancer patients, in order to investigate how personality affects quality of life. Thus, this study aimed to investigate the relationship among personality through the Big Five Inventory (BFI), spirituality, and demoralization and to explore their impact on their quality of life.

METHODS

A sample of 210 end-of-life Italian cancer patients were assessed with the BFI, the Demoralization Scale (DS), the Functional Assessment of Chronic Illness Therapy-Spiritual Well-Being (FACIT-SP-12), the Functional Assessment of Cancer Therapy Scale-General Measure (FACT-G), and the Karnofsky performance status.

RESULTS

Correlational analysis highlighted a significantly negative relationship between extraversion and agreeableness traits and all the demoralization dimensions. On the other side, neuroticism trait was significantly and positively correlated with the Demoralization Scale (p < 0.01). To understand the impact of these variables on quality of life (FACT-G), we performed a hierarchical multiple regression: in the final model, demoralization remained the strongest contributing factor (β =  - 0.509, p < 0.001), followed by neuroticism (β =  - 0.175, p < 0.001), spirituality (β = 0.163, p = 0.015), and Karnofsky index (β = 0.115, p = 0.012).

CONCLUSION

Our data underlined how both the neuroticism trait and demoralization are correlated with a worst health status in terminal cancer patients, whereas spirituality is a protective factor. The study of personality may allow to better understand the inner patient's experience and improve communication between patient and healthcare staff in order to build and apply better-tailored psychological treatment.

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

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

Analysis of Personality Traits in Patients with Hodgkin Lymphoma

Hodgkin lymphoma (HL) is a highly-curable malignancy mostly affecting young people. As far as we know, there is no published study that has analyzed personality profiles in HL nor their potential role in lymphomagenesis, natural history, or response to treatment. We aim to explore the personality traits of HL patients, as well as the prevalence of mental disorders and suicide ideas. We retrospectively identified all alive HL patients from three centers (Son Espases and Son Llatzer University Hospitals and Hospital del Mar of Barcelona) for using NEO Five-Factor Inventory (NEO-FFI) and Personality Inventory for DSM-5 Brief Form. Patients with HL showed significantly higher neuroticism scores and lower conscientiousness, extraversion, and openness. Considering maladaptive personality traits, HL patients showed higher levels of detachment and psychoticism. All of these translated into the fact that HL patients showed more than double the prevalence of mental illnesses (41%) and more than triple the prevalence of suicidal ideation or attempts than the general population (15 and 6%, respectively). An exploratory analysis of biomarkers associated with HL personality traits showed that higher scores of neuroticism correlated with more elevated erythrocyte sedimentation rate (ESR) and red cell distribution width (RDW), suggesting a potential link between neuroticism and proinflammatory activity in HL.

Personality pathways to mortality: Interleukin-6 links conscientiousness to mortality risk

Personality is associated consistently with mortality hazards, but the physiological pathways are not yet clear. Immune system dysregulation may be one such pathway due to its role in age-related morbidity and mortality. In this preregistered study, we tested whether interleukin-6 (IL-6) and C-reactive protein (CRP) mediated the associations between personality traits and mortality hazards. The sample included 957 participants (M ± SD = 58.65 ± 11.51 years; range = 35-86 years) from the Midlife in the United States Survey that had 14 years of follow-up. Higher conscientiousness was associated with lower mortality hazards, with each one standard deviation higher conscientiousness associated with a 35% lower mortality risk. IL-6, but not CRP, partially mediated this association, with IL-6 accounting for 18% of this association in the fully adjusted model. While there was initial evidence that the biomarkers mediated both neuroticism and agreeableness and mortality risk, the indirect effects were not significant when controlling for the sociodemographic variables. Taken together, higher conscientiousness may lead to a longer life partially as a result of lower IL-6. This work highlights the importance of biological pathways that link personality to future mortality risk.

Going beyond the mean in examining relationships of adolescent non-cognitive skills with health-related quality of life and biomarkers in later-life

Several studies have established associations between early-life non-cognitive skills and later-life health and health behaviours. However, no study addresses the more important policy concern about how this relationship varies along the health distribution. We use unconditional quantile regression to analyse the effects of adolescent non-cognitive skills across the distributions of the health-related quality of life at age 50 and biomarkers at age 45 years. We examine the effects of measures of conscientiousness, agreeableness and neuroticism recorded at age 16 for 3585 individuals from the National Child Development Study. Adolescent conscientiousness is positively associated with ability to cope with stress and negatively associated with risk of cardiovascular disease in middle-age. Adolescent agreeableness is associated with higher health-related quality of life and lower physiological 'wear and tear', but negatively associated with ability to cope with stress in middle-age. Adolescent neuroticism is associated with lower health-related quality of life, higher physiological 'wear and tear', and a higher risk of cardiovascular disease in middle-age. All of these associations are stronger at the lower end of the health distribution except for the cardiovascular risk biomarkers. These associations are robust to correcting for attrition using inverse probability weighting and consistent with causal bounds assuming proportional selection on observables and unobservables. They suggest policies that improve non-cognitive skills in adolescence could offer most long-term health benefit to those with the poorest health.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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