Personality and risk for Alzheimer's disease in adults 72 years of age and older: a 6-year follow-up

Does personality affect the cognitive decline in aging? A systematic review

Cognitive decline is a natural consequence of aging, but several genetic, environmental, and psychological factors can influence its trajectories. Among the most enduring factors, the Big Five personality traits - defined as relatively stable tendencies to think, behave, and react to the environment - can influence both directly (e.g., by physiological correlates) and indirectly (e.g., healthy or risky behaviors) the risk of developing dementia and mild cognitive impairment (MCI) - a preclinical form of cognitive decline. Despite the great amount of studies focusing on the relationship between personality and cognitive decline, an updated systematic synthesis of the results including a broader range of study designs is still lacking. This systematic review aims to summarize the findings of studies investigating: (i) differences in personality traits between groups of healthy individuals and those with MCI, (ii) the impact of personality traits on the risk for both MCI and dementia, and (iii) changes in personality traits among individuals progressing from normal cognition to MCI. Neuroticism emerged as a significant risk factor for MCI and dementia; Conscientiousness and Openness appear to offer protection against dementia and moderate cognitive decline. Overall, these findings suggest a pivotal role of personality structure in shaping cognitive outcomes on the long run.

The relationship between personality and cognition in older adults with and without early-onset depression

Introduction

It is well established that personality traits impact cognition, as certain personality factors are associated with performance in specific cognitive domains. However, the findings on the relationships between the Big Five traits and cognition are mixed. Additionally, few studies have explored these relationships in older adults with a history of depression. The present study aimed to (a) evaluate the impact of the Big Five personality traits in older adults with and without a lifetime history of depression; and (b) test the hypotheses that higher trait neuroticism would correlate negatively with cognitive performance, while openness to experience would correlate positively with cognition.

Methods

The sample consisted of 138 participants between the ages of 55 and 78 (M = 65.56, SD = 6.36). Sixty-two participants met criteria for current or remitted Major Depressive Disorder, while 76 had no history of depression or other mental health disorders. Participants underwent comprehensive neuropsychological testing. Personality was assessed using the NEO Personality Inventory-Revised (NEO-PI-R), while depression status was determined using the Structured Clinical Interview for DSM-5 (SCID-5). Following a series of Pearson correlations of cognitive variables and the five personality factors, linear regression models were estimated for each significant correlation. Demographic variables (i.e., age, education and sex) were entered in block 1, depression status (never vs. ever) was entered in block 2, and the personality factor score, or sub-facet was entered in block 3.

Results

Neuroticism was not associated with cognitive performance on any outcome measure. The facets Openness to Feelings and Openness to Values were positively related to phonemic fluency. Further Openness to Values was positively related to cognitive flexibility.

Discussion

Our results suggest that older people who are (a) more capable of identifying and understanding their feelings and the feelings of others, and (b) who are more willing to re-examine social, political, and religious values perform stronger on tasks measuring verbal fluency and cognitive flexibility, which are aspects of executive functioning. Interventions that aim to enhance open mindedness in older adults may have a parallel impact on improving executive functioning, though this would need to be examined prospectively.

Associations between personality and psychological characteristics and cognitive outcomes among older adults

Prior research has shown that some personality traits are associated with cognitive outcomes and may confirm risk or protection against cognitive decline. The present study expands on previous work to examine the association between a more comprehensive set of psychological characteristics and cognitive performance in a diverse cohort of older adults. We also examine whether controlling for brain atrophy influences the association between psychological characteristics and cognitive function. A total of 157 older adults completed a battery of psychological questionnaires (Openness to Experience, Conscientiousness, Agreeableness, Neuroticism, Extraversion, positive affect, negative affect-sadness, negative affect-anger, sense of purpose, loneliness, grit, and self-efficacy). Cognitive outcomes were measured across multiple domains: episodic memory, semantic memory, executive function, and spatial ability. Baseline brain (MRI) variables included gray matter, hippocampus, and total white matter hyperintensity volume. Parallel process, multilevel models yielded intercept (individual cognitive domain scores) and linear slope (global cognitive change) random effects for the cognitive outcomes. Positive affect (β = 0.013, SE = 0.005, p = .004) and Openness (β = 0.018, SE = 0.007, p = .009) were associated with less cognitive change, independent of baseline brain variables and covariates. Greater sadness predicted more cognitive decline when controlling for covariates, but not brain atrophy. A variety of psychological characteristics were associated with the cross-sectional measures of cognition. This study highlights the important impact of positive and negative affect on reducing or enhancing the risk of longitudinal cognitive decline. Such findings are especially important, given the available efficacious interventions that can improve affect. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Personality predictors of dementia diagnosis and neuropathological burden: An individual participant data meta-analysis

INTRODUCTION

The extent to which the Big Five personality traits and subjective well-being (SWB) are discriminatory predictors of clinical manifestation of dementia versus dementia-related neuropathology is unclear.

METHODS

Using data from eight independent studies (Ntotal = 44,531; Ndementia = 1703; baseline Mage = 49 to 81 years, 26 to 61% female; Mfollow-up range = 3.53 to 21.00 years), Bayesian multilevel models tested whether personality traits and SWB differentially predicted neuropsychological and neuropathological characteristics of dementia.

RESULTS

Synthesized and individual study results indicate that high neuroticism and negative affect and low conscientiousness, extraversion, and positive affect were associated with increased risk of long-term dementia diagnosis. There were no consistent associations with neuropathology.

DISCUSSION

This multistudy project provides robust, conceptually replicated and extended evidence that psychosocial factors are strong predictors of dementia diagnosis but not consistently associated with neuropathology at autopsy.

HIGHLIGHTS

N(+), C(-), E(-), PA(-), and NA(+) were associated with incident diagnosis. Results were consistent despite self-report versus clinical diagnosis of dementia. Psychological factors were not associated with neuropathology at autopsy. Individuals with higher conscientiousness and no diagnosis had less neuropathology. High C individuals may withstand neuropathology for longer before death.

Openness to Experience is associated with neural and performance measures of memory in older adults

Age-related decline in episodic memory performance is a well-replicated finding across numerous studies. Recent studies focusing on aging and individual differences found that the Big Five personality trait Openness to Experience (hereafter: Openness) is associated with better episodic memory performance in older adults, but the associated neural mechanisms are largely unclear. Here, we investigated the relationship between Openness and memory network function in a sample of 352 participants (143 older adults, 50-80 years; 209 young adults, 18-35 years). Participants underwent functional magnetic resonance imaging (fMRI) during a visual memory encoding task. Functional memory brain-network integrity was assessed using the similarity of activations during memory encoding (SAME) scores, which reflect the similarity of a participant's memory network activity compared to prototypical fMRI activity patterns of young adults. Openness was assessed using the NEO Five-Factor Inventory. Older vs young adults showed lower memory performance and higher deviation of fMRI activity patterns (i.e. lower SAME scores). Specifically in older adults, high Openness was associated with better memory performance, and mediation analysis showed that this relationship was partially mediated by higher SAME scores. Our results suggest that trait Openness may constitute a protective factor in cognitive aging by better preservation of the brain's memory network.

An Investigation of Affective Personality Traits in Alzheimer's Disease: SEEKING as a Possible Predictor for Early-Stage Alzheimer's Dementia

OBJECTIVE

The aim of the current study was to investigate affective personality traits in Alzheimer's disease, a neurodegenerative condition mainly characterized by episodic memory impairment.

METHOD

The sample included 69 participants from 3 diagnostic categories. Twenty-five participants were diagnosed with subjective cognitive impairment (SCI), 26 participants were diagnosed with mild cognitive impairment of the amnestic type (aMCI), and the remaining 18 participants were diagnosed with early-stage Alzheimer's dementia (ADD). Diagnostic labels were given as a result of detailed neurological, neuropsychological, and neuroradiological assessment. Affective personality traits were assessed via Affective Neuroscience Personality Scales (ANPS).

RESULTS

The only significant intergroup difference was obtained for the SEEKING subscale of ANPS. Here, ADD group scored significantly lower compared to the SCI group. The results of logistic regression analysis also indicated that SEEKING score successfully predicted early-stage ADD diagnosis.

CONCLUSION

The results suggest that a specific personality constellation characterized by reduced investment in the outside world might be associated with Alzheimer's disease, either as a risk factor or a byproduct of the neurodegenerative process initiated by AD pathology.

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 traits and disorders in Alzheimer's disease

BACKGROUND

The relationships between axis II personality disorders and the normative personality traits were explored in the context of current and pre-morbid personality assessment in Alzheimer's disease (AD).

METHODS

The study was conducted with four groups who were administered the NEO-FFI and the PDQ-4+, in the form of individual interview sessions. Current personality measure: consisting of 44 female participants (AD group) and, the control group, consisting of 80 female participants from the population at large. Pre-morbid personality measure: AD group informants (n = 40); control group informants (n = 42).

RESULTS

The results are in line with the literature review and provide new research data. By factorial discriminant analysis, the current and pre-morbid personality variables that differentiate AD from control groups are identified. The personality traits variables are the best discriminators such as low agreeableness, low openness to experience, and high neuroticism, suggesting that the maladaptive personality functioning can be described extending the range of psychopathology to a dimensional approach.

CONCLUSIONS

The study of personality variables seems to suggest, in their inclusion, the possibility to increase sensitivity toward an assessment in AD.

Insights about personality traits and cognitive performance and decline in adults 51-59 Years old from the Wisconsin longitudinal study

OBJECTIVES

To delineate midlife personality dimensions of early cognitive change in an age-homogenous sample of U.S. older adults.

DESIGN

Longitudinal study of 6133 adults from the Wisconsin Longitudinal Study (WLS).

MEASURES

Middle-aged participants (mean age = 53.2; SD = 0.6) from the WLS completed the 'Big-5' personality assessment in 1992. Mixed effects models examined whether midlife personality traits were associated with change in cognitive performance from participant's mid-60s (2004-2005) to early 70s (2011). The cognitive battery assessed abstract reasoning (AR), category fluency (CF), working memory (WM), and delayed verbal memory (DVM). Models adjusted for sex, education, and subjective health.

RESULTS

High Openness was a significant predictor of change in AR, CF, and DVM. These cognitive outcomes declined less among those with high Openness, but the effect sizes for Openness by time were small (R2 s < 0.01). AR and CF were characterized by higher overall performance with high Openness, but with relatively parallel change for the highest and lowest Openness quartiles. There was no advantage of Openness to DVM by the second assessment. High Conscientiousness was a predictor of more change for DVM, though the effect size was small (R 2  < 0.01).

CONCLUSIONS

None of the midlife personality traits were uniformly associated with change in cognitive performance in early older adulthood. High midlife Openness had the most noteworthy impact on cognition. Interventions designed to target Openness have potential to elevate and maintain a higher threshold of performance in some cognitive domains, but may only have a small impact on cognitive change.

Facets of Personality and Risk of Cognitive Impairment: Longitudinal Findings in a Rural Community from Sardinia

Background: Few studies have examined the associations between personality facets and dementia risk and rarely included individuals from rural settings or with low education. Objective: To examine the association between personality and the risk of cognitive impairment. Methods: Participants (N = 1,668; age 50 to 94 at baseline; 56.4% women; 86.5% less than high school diploma) were from a rural region of Sardinia (Italy) who completed the Revised NEO Personality Inventory (NEO-PI-R) during the first wave (2001–2004) and the Mini-Mental State Examination (MMSE) at waves two to five (2005–2021). Cox regression was used to test personality and covariates as predictors of cognitive impairment based on MMSE education-adjusted cutoffs. Results: During the up to 18-year follow-up (M = 10.38; SD = 4.76), 187 individuals (11.2%) scored as cognitively impaired. Participants with higher neuroticism (particularly the depression facet [HR = 1.22, 95% CI = 1.06–1.40]), and lower agreeableness (particularly the modesty facet [HR = 0.83, 95% CI = 0.71–0.97]) and lower conscientiousness (particularly the dutifulness facet [HR = 0.78, 95% CI = 0.67–0.92]) were at higher risk of cognitive impairment. Lower warmth ([HR = 0.75, 95% CI = 0.65–0.87], facet of extraversion) and ideas ([HR = 0.76, 95% CI = 0.65–0.89], facet of openness) were also associated with increased risk of impairment. These associations were virtually unchanged in models that accounted for other risk factors, including smoking, depression, obesity, hypertension, diabetes, and apolipoprotein E (APOE) ɛ4 carrier status. Across the five domains, sex and the APOE variant did not moderate the associations. Conclusion: In a sample with demographic characteristics underrepresented in dementia research, this study identifies personality domains and facets most relevant to the risk of cognitive impairment.

Genome-wide association of polygenic risk extremes for Alzheimer's disease in the UK Biobank

In just over a decade, advances in genome-wide association studies (GWAS) have offered an approach to stratify individuals based on genetic risk for disease. Using recent Alzheimer's disease (AD) GWAS results as the base data, we determined each individual's polygenic risk score (PRS) in the UK Biobank dataset. Using individuals within the extreme risk distribution, we performed a GWAS that is agnostic of AD phenotype and is instead based on known genetic risk for disease. To interpret the functions of the new risk factors, we conducted phenotype analyses, including a phenome-wide association study. We identified 246 loci surpassing the significance threshold of which 229 were not reported in the base AD GWAS. These include loci that showed suggestive levels of association in the base GWAS and loci not previously suspected to be associated with AD. Among these, there are loci, such as IL34 and KANSL1, that have since been shown to be associated with AD in recent studies. We also show highly significant genetic correlations with multiple health-related outcomes that provide insights into prodromal symptoms and comorbidities. This is the first study to utilize PRS as a phenotype-agnostic group classification in AD genetic studies. We identify potential new loci for AD and detail phenotypic analysis of these PRS extremes.

Associations of Polygenic Risk Score for Late-Onset Alzheimer's Disease With Biomarkers

Late-onset Alzheimer's disease (LOAD) is a common irreversible neurodegenerative disease with heterogeneous genetic characteristics. Identifying the biological biomarkers with the potential to predict the conversion from normal controls to LOAD is clinically important for early interventions of LOAD and clinical treatment. The polygenic risk score for LOAD (AD-PRS) has been reported the potential possibility for reliably identifying individuals with risk of developing LOAD recently. To investigate the external phenotype changes resulting from LOAD and the underlying etiology, we summarize the comprehensive associations of AD-PRS with multiple biomarkers, including neuroimaging, cerebrospinal fluid and plasma biomarkers, cardiovascular risk factors, cognitive behavior, and mental health. This systematic review helps improve the understanding of the biomarkers with potential predictive value for LOAD and further optimizing the prediction and accurate treatment of LOAD.

CAG Repeats Within the Non-pathological Range in the HTT Gene Influence Personality Traits in Patients With Subjective Cognitive Decline: A 13-Year Follow-Up Study

OBJECTIVE

HTT is a gene containing a key region of CAG repeats. When expanded beyond 39 repeats, Huntington disease (HD) develops. HTT genes with <35 repeats are not associated with HD. The biological function of CAG repeat expansion below the non-pathological threshold is not well understood. In fact higher number of repeats in HTT confer advantageous changes in brain structure and general intelligence, but several studies focused on establishing the association between CAG expansions and susceptibility to psychiatric disturbances and to other neurodegenerative disease than HD. We hypothesized that HTT CAG repeat length below the pathological threshold might influence mood and personality traits in a longitudinal sample of individuals with Subjective Cognitive Decline.

METHODS

We included 54 patients with SCD. All patients underwent an extensive neuropsychological battery at baseline, APOE genotyping and analysis of HTT alleles. We used the Big Five Factors Questionnaire (BFFQ) and Hamilton Depression Rating Scale (HDRS), respectively, to assess personality traits of patients and depression at baseline. Patients who did not progress to Mild Cognitive Impairment (MCI) had at least 5-year follow-up time.

RESULTS

In the whole sample, CAG repeat number in the shorter HTT allele was inversely correlated with conscientiousness (Pearson = -0.364, p = 0.007). There was no correlation between HDRS and CAG repeats. During the follow-up, 14 patients [25.93% (95% C.I. = 14.24-37.61)] progressed to MCI (MCI⁺) and 40 [74.07% (95% C.I. = 62.39-85.76)] did not (MCI^-). When we performed the same analysis in the MCI⁺ group we found that: CAG repeat length on the shorter allele was inversely correlated with energy (Pearson = 0.639, p = 0.014) and conscientiousness (Pearson = -0.695, p = 0.006). CAG repeat length on the longer allele was inversely correlated with conscientiousness (Pearson = -0.901, p < 0.001) and directly correlated with emotional stability (Pearson = 0.639, p = 0.014). These associations were confirmed also by multivariate analysis. We found no correlations between BFFQ parameters and CAG repeats in the MCI^- group.

DISCUSSION

Personality traits and CAG repeat length in the intermediate range have been associated with progression of cognitive decline and neuropathological findings consistent with AD. We showed that CAG repeat lengths in the HTT gene within the non-pathological range influence personality traits.

The Moderating Role of Sleep Quality on the Association between Neuroticism and Frontal Executive Function in Older Adults

OBJECTIVE/BACKGROUND

Personality traits are regarded as risk factors for cognitive impairment in older adults, while sleep disturbance and physical inactivity are also considered as modifiable risk factors. Therefore, it could be beneficial to investigate the effects of those modifiable risk factors on the relationship between personality traits and cognitive functions, to prepare appropriate strategies for mitigating cognitive impairment.

PARTICIPANTS

A total of 155 cognitively unimpaired older adults were included.

METHODS

All participants underwent cognitive function tests using the Seoul Neuropsychological Screening Battery and examinations for personality traits using the Big Five Inventory. Individual physical activity and sleep quality were assessed using the International Physical Activity Questionnaire and Pittsburgh Sleep Quality Index, respectively. A hierarchical linear multiple regression analysis was performed to demonstrate the direct association between personality traits and cognitive functions, and the multiple moderator analysis was used to analyze the moderating effects of lifestyle factors on this association.

RESULTS

Among the five personality traits, only neuroticism was negatively associated with the frontal executive and visuospatial functions after controlling age, sex, and years of education. Interestingly, the negative relationship between neuroticism and frontal executive function was alleviated in older adults with higher sleep quality.

CONCLUSIONS

Our findings demonstrated that higher sleep quality has significant moderating effects on the negative association between neuroticism and frontal executive functions in older adults, which suggests intervention for improving sleep quality such as cognitive behavioral therapy can be considered in older adults who have personality traits associated with a high risk of cognitive impairment.

Subjective Cognitive Decline: Is a Resilient Personality Protective Against Progression to Objective Cognitive Impairment? Findings from Two Community-Based Cohort Studies

BACKGROUND

Subjective cognitive decline (SCD) is related to personality functioning and risk of subsequent objective cognitive impairment.

OBJECTIVE

The aim of this study was to examine whether lower neuroticism and higher conscientiousness-resilient personality traits-protect against conversion from SCD to objective cognitive impairment in two longitudinal community-based cohorts.

METHODS

Data from the Health and Retirement Study (N = 1,741, Mean age = 68.64 years, Follow-up mean = 7.34 years) and the National Health and Aging Trends Survey (N = 258, Mean age = 79.34 years, Follow-up mean = 4.31 years) were analyzed using Cox regression analysis, controlling for sociodemographic covariates, symptoms of anxiety and depression, and apolipoprotein ɛ4.

RESULTS

The pooled results showed that lower neuroticism and higher conscientiousness were associated with decreased risk of conversion from SCD to objective cognitive impairment.

CONCLUSION

Among individuals with SCD, those with a resilient personality may have more cognitive and psychological reserve to maintain cognitive functioning and delay conversion to objective cognitive impairment. The findings further contribute to a better understanding of personality along the cognitive continuum: The observed effect sizes were smaller than those reported in cognitively normal individuals but larger than in individuals with mild cognitive impairment. Personality could provide useful information to identify individuals with SCD who may develop objective cognitive impairment-namely those who hold a vulnerable personality (higher neuroticism, lower conscientiousness).

Neuroticism Is Associated with Tau Pathology in Cognitively Unimpaired Individuals with Autosomal Dominant Alzheimer's Disease

BACKGROUND

Greater neuroticism has been associated with higher risk for Alzheimer's disease (AD) dementia. However, the directionality of this association is unclear. We examined whether personality traits differ between cognitively-unimpaired carriers of autosomal-dominant AD (ADAD) and non-carriers, and are associated with in vivo AD pathology.

OBJECTIVE

To determine whether personality traits differ between cognitively unimpaired ADAD mutation carriers and non-carriers, and whether the traits are related to age and AD biomarkers.

METHODS

A total of 33 cognitively-unimpaired Presenilin-1 E280A mutation carriers and 41 non-carriers (ages 27-46) completed neuropsychological testing and the NEO Five-Factor Personality Inventory. A subsample (n = 46; 20 carriers) also underwent tau and amyloid PET imaging.

RESULTS

Carriers reported higher neuroticism relative to non-carriers, although this difference was not significant after controlling for sex. Neuroticism was positively correlated with entorhinal tau levels only in carriers, but not with amyloid levels.

CONCLUSION

The finding of higher neuroticism in carriers and the association of this trait with tau pathology in preclinical stages of AD highlights the importance of including personality measures in the evaluation of individuals at increased risk for cognitive impairment and dementia. Further research is needed to characterize the mechanisms of these relationships.

Association of Stress with Risk of Dementia and Mild Cognitive Impairment: A Systematic Review and Meta-Analysis

BACKGROUND

Although many studies have investigated the association between stress and risk of dementia, findings are inconsistent due to the variation in the measures used to assess stress.

OBJECTIVE

We conducted a systematic review and meta-analysis to investigate the association between psychological stress (including neuroticism, stressful life events, and perceived stress) and the risk of incident dementia and mild cognitive impairment in adults.

METHODS

PsycINFO, Embase, and MEDLINE were searched to October 2020 for eligible observational, prospective studies. Of the 1,607 studies screened, 26 (24 unique cohorts) were included in the qualitative analysis and 16 (15 unique cohorts) were included in the quantitative analysis.

RESULTS

Across studies, higher perceived stress was significantly associated with an increased risk of mild cognitive impairment (Cases/Total N = 207/860: hazard ratio [HR] = 1.19, 95% confidence interval [CI] = 1.03-1.38) and all-cause dementia (Cases/Total N = 203/1,882: HR = 1.44, 95% CI = 1.07-1.95). Exposure to two or more stressful life events (versus none) was significantly associated with an increased risk of all-cause dementia (Cases/Total N = 3,354/11,597: HR = 1.72, 95% CI = 1.14-2.60), while one or more stressful life events was not. Higher neuroticism was significantly associated with an increased risk of Alzheimer's disease dementia (Cases/Total N = 497/4,771: HR = 1.07, 95% CI = 1.01-1.12), but not all-cause dementia.

CONCLUSION

This review suggests that psychological stress in adulthood is associated with an increased risk of dementia. Further research is needed to clarify the mechanisms underlying these associations.

Neuroticism and Risk of Parkinson's Disease: A Meta-Analysis

BACKGROUND

Neuroticism is linked to mood disorders and Alzheimer's disease, but fewer studies have tested the prospective association with Parkinson's disease (PD).

OBJECTIVES

To examine the association between neuroticism and risk of PD in a large cohort and a meta-analysis of prospective cohort studies.

METHODS

Participants from the UK Biobank (N = 490,755) completed a neuroticism scale in 2006-2010. Incident PD was ascertained using electronic health records or death records up to 2018. The systematic search and meta-analysis followed the MOOSE guidelines.

RESULTS

During 11.91 years of follow-up (mean = 8.88 years; 4,360,105 person-years) 1142 incident PD cases were identified. Neuroticism was associated with higher risk of incident PD, both as continuous (HR = 1.28; 95% CI: 1.21-1.36) and categorical variable (top vs. bottom quartiles: HR = 1.88; 95% CI: 1.60-2.22). The association remained significant after accounting for age, sex, smoking, physical activity, anxiety, and depressed mood, and after excluding cases that occurred within the first 5 years of follow-up. The associations were similar for women and men and across levels of socioeconomic status. Random-effect meta-analysis of four prospective studies (N = 548,284) found neuroticism associated with increased risk of incident PD (HR = 1.82; 95% CI: 1.59-2.08; P = 7.31-19 ). There was no evidence of heterogeneity across studies with follow-ups ranging from one to four decades.

CONCLUSION

The results from the large UK Biobank and meta-analysis of prospective studies indicate that neuroticism is consistently associated with a higher risk of incident PD. © 2021 International Parkinson and Movement Disorder Society.

A coordinated analysis of the associations among personality traits, cognitive decline, and dementia in older adulthood

There are individual differences in the rates of cognitive decline across later adulthood. Personality traits are among the factors that may account for these differences. The current project investigated whether personality traits were associated with trajectories of cognitive decline, and whether the associations were different before and after dementia diagnosis. The data was analyzed using linear mixed effects regression. Across study aims is a focus on replicability and generalizability. Each question was addressed in four independent longitudinal studies (EAS, MAP, ROS, SATSA), then meta-analyzed, providing estimates of replicability. Results indicated that low neuroticism and high openness were associated with total cognitive function. We detected evidence for cognitive decline in all four samples, and openness was associated with decline post dementia diagnosis.

Evaluation relationships between subjective wellbeing, personality traits, and Alzheimer's disease: A two-sample Mendelian randomization study

OBJECTIVE

Observational studies have suggested that subjective wellbeing and personality traits link to risk of Alzheimer's disease (AD), but it is unclear if these associations are causal.

METHODS

We performed two-sample Mendelian randomization to assess potential causality. Genetic associations were obtained from the largest genome-wide association studies in Social Science Genetic Association Consortium (N = 298,420), Genetics of Personality Consortium (N = 81,036), and four independent consortia of AD (N = 455,258). We run the inverse variance weighted (IVW) approach as one primary analysis. A Bonferroni-corrected threshold of p < 8.33 × 10-3 was considered significant, and p values between 8.33 × 10-3 and 0.05 were considered to be suggestive of an association.

RESULTS

The suggestive association with decreased risk of AD was noted for a genetically predicted 1-SD increase in subjective wellbeing (odds ratio = 0.963, 95% confidence interval = 0.930-0.997; p = 0.032). Genetically predicted greater neuroticism was significantly associated with lower subjective wellbeing (β = -0.077; p = 0.004). No putative personality traits were significantly associated with AD risk after correction for multiple tests, including agreeableness (β = -0.0010; p = 0.477), conscientiousness (β = 0.0018; p = 0.270), openness (β = 0.0004; p = 0.738), neuroticism (β = -0.0098; p = 0.262), or extraversion (β = 0.0120; p = 0.262).

CONCLUSIONS

Subjective wellbeing may independently reduce the risk of AD. Residual confounding is likely to be responsible for the previous observational relationships between personality traits and AD.

Is personality associated with dementia risk? A meta-analytic investigation

This study provides a quantitative synthesis of the prospective associations between personality traits (neuroticism, extraversion, openness, agreeableness, conscientiousness) and the risk of incident Alzheimer's disease and related dementias. We conducted five separate meta-analyses with 8-12 samples (N = 30,036 to 33,054) that were identified through a systematic literature search following the MOOSE guidelines. Higher neuroticism (HR = 1.24, 95% CI [1.17, 1.31]) and lower conscientiousness (HR = 0.77, 95% CI [0.73, 0.81]) were associated with increased dementia risk, even after accounting for covariates such as depressive symptoms. Lower extraversion (HR = 0.92, 95% CI [0.86, 0.97]), openness (HR = 0.91, 95% CI [0.86, 0.96]), and agreeableness (HR = 0.90, 95% CI [0.83, 0.98]) were also associated with increased risk, but these associations were less robust and not significant in fully adjusted models. No evidence of publication bias was found. The strength of associations was unrelated to publication year (i.e., no evidence of winner's curse). Meta-regressions indicated consistent effects for neuroticism, openness, and conscientiousness across methods to assess dementia, dementia type, follow-up length, sample age, minority, country, and personality measures. The association of extraversion and agreeableness varied by country. Our findings indicate robust associations of neuroticism and conscientiousness with dementia risk.

Personality and Dementia Risk in England and Australia

Evidence for the relation between personality and dementia risk comes mainly from American samples. We tested whether personality-dementia links extend to populations from England and Australia. Data from the English Longitudinal Study of Ageing (ELSA; N = 6,887; Follow-up mean: 5.64 years) and the Household, Income and Labour Dynamics in Australia (HILDA; N = 2,778; Follow-up mean: 10.96 years) were analyzed using Cox PH models. In both samples, higher neuroticism was associated with increased dementia risk. In ELSA, lower conscientiousness was related to increased risk. In HILDA, conscientiousness had a similar effect but did not reach statistical significance. The present work found a consistent association for neuroticism and suggests similar personality-dementia links across demographic groups and high-income countries.

Personality Moderates Intervention Effects on Cognitive Function: A 6-Week Conversation-Based Intervention

BACKGROUND AND OBJECTIVES

Social isolation is associated with a higher risk of dementia. We previously conducted and showed the efficacy of an intervention which uses conversation (the core component of social interactions) as a tool to enhance cognitive function. We now explore whether cognitive improvements through conversation-based intervention depend on an individual's personality.

RESEARCH DESIGN AND METHODS

We reexamined data from a 6-week randomized controlled trial (ClinicalTrials.gov Number: NCT01571427) to determine whether conversation-based intervention effects were moderated by personality traits in 83 older adults (mean age = 80.51 years, 49 cognitively intact, 34 individuals with mild cognitive impairment). The intervention group participated in daily 30-min face-to-face semi-structured conversations with trained interviewers through a web-enabled system for 6 weeks. At baseline, psychosocial questionnaires and a neuropsychological battery were completed.

RESULTS

Intervention group participants with high agreeableness, conscientiousness, and extraversion exhibited significant improvements in language-based executive function tasks beyond changes in the control group (ps < .05). An opposite pattern for delayed recall memory and working memory tasks emerged among highly extraverted participants (ps < .05).

DISCUSSION AND IMPLICATIONS

Our exploratory findings suggest the adaptive role of personality traits in conversation-based cognitive interventions may be limited to tasks incorporating a language component, and offer initial evidence for personalized approaches to cognitive health in late life.

Conscientiousness is associated with less amyloid deposition in cognitively normal aging

Little is known about the association between personality and Alzheimer's disease (AD) biomarkers, and existing results are inconsistent. We aimed to determine whether personality was associated with β-amyloid (Aβ) accumulation in cognitively normal aging. One hundred twenty-nine participants were included in this cross-sectional study. Personality was measured with the Big Five Inventory (BFI) and brain Aβ deposition was assessed with [11C] Pittsburgh compound B (PiB)-positron emission tomography (PET) imaging. Conscientiousness scores had a negative association with global PiB distribution volume ratio (DVR) in all participants after adjusting for age, sex, education, and vascular risk factors (β[SE] = -0.19[0.09], 95% confidence interval [CI: -0.35, -0.02], p = .031), while agreeableness, extraversion, neuroticism, and openness had no association with global PiB DVR. Assuming the relative stability of personality traits, these findings suggest that conscientiousness may protect against Aβ accumulation in cognitively normal aging through mechanisms that are as yet unknown. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Self-Reported Personality Traits and Informant-Rated Cognition: A 10-Year Prospective Study

Personality traits, such as higher Neuroticism and lower Conscientiousness, are associated with risk of Alzheimer's disease and other dementias. A diagnosis of dementia relies, in part, on informant ratings of the individual's cognitive status. Here we examine whether self-reported personality traits are associated with four measures of informant-rated cognition up to a decade later. Participants from the Health and Retirement Study (N = 2,536) completed a five-factor model measure of personality in 2006 or 2008. Informants completed the 2016 Harmonized Cognitive Assessment Protocol (HCAP), which included ratings of the participant's current cognitive functioning and change in cognitive function over the last decade assessed with the IQCODE, Blessed, 1066, and CSID. Controlling for characteristics of the participant, informant, and their relationship, higher Neuroticism and lower Conscientiousness were associated consistently with worse informant-rated cognition. The association between Openness and better informant-rated cognition was due primarily to higher baseline cognitive function. Extraversion and Agreeableness were associated with better informant-rated cognition only among participants who were cognitively intact at follow-up. The present research suggests that knowledgeable informants are able to detect cognitive deficits associated with personality.

The power of personality in successful ageing: a comprehensive review of larger quantitative studies

In this paper, we highlighted links between personality traits and successful ageing through a systematic review of recent empirical studies. Particularly, we addressed the question of whether personality traits are related to successful ageing and, if so, why and how? Answers to this question provided, for example, arguments that supported personality's role in planning an individual's future based on self-knowledge, thereby contributing to a sense of identity throughout their life. Then, considering longitudinal studies, we examined whether personality is stable over one's life course, or does it change and, if so, why and under what conditions? Answers to this question gave substance to the idea that a stable personality allows for continuous and consistent development. In addition, certain personality changes are likely to allow an individual to develop the resilience to better adapt to life's challenges. Therefore, the arguments brought by these two questions can help clarify the modulating role of personality for successful ageing via health and well-being outcomes. These insights may contribute to the development of new prevention approaches, more focused on inter- and intraindividual differences, to promote successful ageing.

The Relation Between Personality and Biomarkers in Sensitivity and Conversion to Alzheimer-Type Dementia

OBJECTIVES

The present study explored relationships among personality, Alzheimer's disease (AD) biomarkers, and dementia by addressing the following questions: (1) Does personality discriminate healthy aging and earliest detectable stage of AD? (2) Does personality predict conversion from healthy aging to early-stage AD? (3) Do AD biomarkers mediate any observed relationships between personality and dementia status/conversion?

METHODS

Both self- and informant ratings of personality were obtained in a large well-characterized longitudinal sample of cognitively normal older adults (N = 436) and individuals with early-stage dementia (N = 74). Biomarkers included amyloid imaging, hippocampal volume, cerebral spinal fluid (CSF) Aβ42, and CSF tau.

RESULTS

Higher neuroticism, lower conscientiousness, along with all four biomarkers strongly discriminated cognitively normal controls from early-stage AD individuals. The direct effects of neuroticism and conscientiousness were only mediated by hippocampal volume. Conscientiousness along with all biomarkers predicted conversion from healthy aging to early-stage AD; however, none of the biomarkers mediated the relationship between conscientiousness and conversion. Conscientiousness predicted conversion as strongly as the biomarkers, with the exception of hippocampal volume.

CONCLUSIONS

Conscientiousness and to a lesser extent neuroticism serve as important independent behavioral markers for AD risk.

Relationships between big-five personality factors and Alzheimer's disease pathology in autosomal dominant Alzheimer's disease

INTRODUCTION

Changes in personality characteristics are associated with the onset of symptoms in Alzheimer's disease (AD) and may even precede clinical diagnosis. However, personality changes caused by disease progression can be difficult to separate from changes that occur with normal aging. The Dominantly Inherited Alzheimer Network (DIAN) provides a unique cohort in which to relate measures of personality traits to in vivo markers of disease in a much younger sample than in typical late onset AD.

METHODS

Personality traits measured with the International Personality Item Pool at baseline from DIAN participants were analyzed as a function of estimated years to onset of clinical symptoms and well-established AD biomarkers.

RESULTS

Both neuroticism and conscientiousness were correlated with years to symptom onset and markers of tau pathology in the cerebrospinal fluid. Self-reported conscientiousness and both neuroticism and conscientiousness ratings from a collateral source were correlated with longitudinal rates of cognitive decline such that participants who were rated as higher on neuroticism and lower on conscientiousness exhibited accelerated rates of cognitive decline.

DISCUSSION

Personality traits are correlated with the accumulation of AD pathology and time to symptom onset, suggesting that AD progression can influence an individual's personality characteristics. Together these findings suggest that measuring neuroticism and conscientiousness may hold utility in tracking disease progression in AD.

The Effect of Personality Traits on Risk of Incident Pre-dementia Syndromes

OBJECTIVES

Personality traits have been shown to be associated with the risk of dementia; less is known about their association with pre-dementia syndromes. The aim of the present study was to examine the role of personality traits as predictors of incident pre-dementia, motoric cognitive risk (MCR), and mild cognitive impairment (MCI) syndromes.

DESIGN

We prospectively examined the association between five personality traits (neuroticism, extraversion, conscientiousness, agreeableness, and openness) and the risk of incident MCR or MCI. MCR builds on MCI operational definitions, substituting the cognitive impairment criterion with slow gait, and it is associated with increased risk for both Alzheimer's disease and vascular dementia.

SETTING

Community based.

PARTICIPANTS

Nondemented participants (n = 524; 62% women) aged 65 years and older.

MEASUREMENTS

Cox proportional hazard analysis, adjusted for demographics and disease burden, was used to evaluate the risk of each pre-dementia syndrome based on baseline personality traits, measured using the Big Five Inventory.

RESULTS

Over a median follow-up of 3 years, 38 participants developed incident MCR, and 69 developed incident MCI (41 non-amnestic and 28 amnestic subtypes). Openness was associated with a reduced risk of developing incident MCR (adjusted hazard ratio [aHR] = .94; 95% confidence interval [CI] = .89-.99), whereas neuroticism was associated with an increased risk of incident non-amnestic MCI (aHR = 1.06; 95% CI = 1.01-1.11). These associations remained significant even after considering the confounding effects of lifestyle or mood. None of the personality traits were associated with MCI overall or amnestic MCI.

CONCLUSION

These findings provide evidence of a distinct relationship between personality traits and development of specific pre-dementia syndromes. J Am Geriatr Soc 68:1554-1559, 2020.

Personality Factors and Subjective Cognitive Decline: The FACEHBI Cohort

Individuals with subjective cognitive decline (SCD) have the perception of memory problems without showing impairment on standardized cognitive tests. SCD has been associated with an increased risk of developing Alzheimer's disease (AD). Neuroticism and openness personality dimensions have also been associated with SCD and AD. From the aforementioned, we aimed to ascertain whether the dimensions and traits defined by the Zuckerman-Kuhlman Personality Questionnaire (ZKPQ) differentiate between individuals with SCD and the general population (GP). A total of 187 participants with SCD and mild affective symptomatology recruited from the Fundació ACE Health Brain Initiative (FACEHBI) project completed the ZKPQ. Each SCD participant was matched by sex and age to an individual from the GP. Both samples included 71 men and 116 women with a mean age of 65.9 years. Results indicated that the SCD group scored significantly lower in Neuroticism-Anxiety and Activity than the GP group. Only Activity remained statistically significant in a multivariate analysis. These findings suggest that individuals with SCD have a low energy level and a dislike for an active and busy life. From the obtained results and knowing additional physical activities may delay the conversion from normal aging to cognitive impairment, we encourage promoting this lifestyle in daily routine. The assessment of personality may result in an SCD plus feature, which may serve as an upgrading strategy for future research.

Personality and Incident Alzheimer's Disease: Theory, Evidence, and Future Directions

Personality, especially the dimensions of neuroticism and conscientiousness, has prospectively predicted the risk of incident Alzheimer's disease (AD). Such a relationship could be explained by personality and AD risk having a common cause such as a gene; by personality creating a predisposition for AD through health behavior or inflammation; by personality exerting a pathoplastic effect on the cognitive consequences of neuropathology; or by AD and personality change existing on a disease spectrum that begins up to decades before diagnosis. Using the 5-dimensional taxonomy of personality, the present review describes how these models might arise, the evidence for each, and how they might be distinguished from one another empirically. At present, the evidence is sparse but tends to suggest predisposition and/or pathoplastic relationships. Future studies using noninvasive assessment of neuropathology are needed to distinguish these 2 possibilities.

Personality disorders characterized by anxiety predict Alzheimer's disease in women: A case-control studies

This research is geared toward the evaluation of current and pre-morbid personality psychopathology in Alzheimer's disease (AD). The study was conducted with four groups who were administered the Personality Diagnostic Questionnaire-4+, mainly in the form of individual interviews. Current measurement: AD Group, 44 female participants (M = 81.36 years); Control Group, 80 female participants from the population at large (M = 75.84 years). Pre-morbid measurement: AD Group Informants (n = 40); Control Group Informants (n = 42). The incidence of all clusters in clinical state are significant, and Cluster B incidence in pre-morbidity is evidenced. Cluster C is highlighted throughout the life course as a predictor. Logistic regression analyses showed that schizotypical, narcissistic, avoidant, obsessive-compulsive, pre-morbid schizotypical, pre-morbid histrionic, and pre-morbid obsessive-compulsive personality disorders, predicted the presence of AD diagnosis, accounting for 49% of the variance. These findings are relevant to research relating personality and psychopathology in Alzheimer's disease.

Five-factor model personality traits and cognitive function in five domains in older adulthood

BACKGROUND

Five-factor model (FFM) personality traits have been associated consistently with risk of Alzheimer's disease and related dementias (ADRD). Less is known about how these traits are associated with functioning in specific domains of cognitive function in older adulthood.

METHODS

Participants (N = 2865) were drawn from the 2016 Harmonized Cognitive Assessment Protocol sub-study of the Health and Retirement Study (HRS). Participants completed a battery of cognitive tasks that measured performance in five domains: Memory (eight tasks), speed-attention-executive (five tasks), visuospatial ability (three tasks), fluency (one task), and numeric reasoning (one task). Participants completed an FFM personality measure as part of the regular HRS assessment in either 2014 or 2016. Linear regression was used to examine the association between the traits and each cognitive task and composite scores for the five domains, controlling for age, sex, race, ethnicity, and education. We also tested whether the associations were moderated by these sociodemographic factors or mental status.

RESULTS

Neuroticism was associated with worse performance on all of the cognitive tasks. Conscientiousness was associated with better performance across all five cognitive domains, although not necessarily with every task. Openness and Agreeableness were associated with better performance in all domains, except for numeric reasoning. Extraversion was associated with better speed-attention-executive and fluency. There was no robust evidence that the association between personality and cognition was moderated by sociodemographic characteristics or global cognitive function.

CONCLUSIONS

Personality traits have pervasive associations with functioning across five cognitive domains. Consistent with the literature on personality and risk of ADRD, Neuroticism and Conscientiousness were associated with cognitive performance in the expected direction in all domains. Extraversion was the only trait that showed domain-specific associations. The present research supports models of personality and health in the context of cognition and suggests that personality is associated with intermediate markers of cognitive health.

Five-factor model personality traits and verbal fluency in 10 cohorts

Personality traits, such as Neuroticism and Conscientiousness, are associated with cognitive outcomes across the life span, including cognitive function in young adulthood and risk of cognitive impairment and dementia in old age. Research on personality and age-related cognition has focused primarily on memory-related tasks and outcomes. The purpose of this research is to address the relation between Five Factor Model personality traits and another critical marker of cognitive function that has received less attention-verbal fluency. We examine this relation across adulthood in 10 cohorts (11 samples) that totaled more than 90,000 participants (age range 16-101). Participants in all samples reported on their personality traits and completed at least one fluency task (semantic and/or letter). A meta-analysis of semantic fluency (N = 86,044) indicated that participants who scored lower in Neuroticism, and higher in Extraversion, Openness, and Conscientiousness, retrieved more words, independent of age, gender, and education. These associations generally replicated for the letter fluency task (3 samples; N = 11,551). Moderation analysis indicated that the associations between personality and semantic fluency were stronger in older samples (except for Openness) and among individuals with lower education. This pattern suggests that these associations are stronger in groups vulnerable to severe cognitive impairment. Personality traits have pervasive associations with fluency tasks that are replicable across samples and age groups. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Negative Affect Is Associated With Higher Risk of Incident Cognitive Impairment in Nondepressed Postmenopausal Women

Background

Positive affect (PA) and negative affect (NA) reflect subjective emotional experiences. Although related to depression and anxiety, these dimensions are distinct constructs representing affective states and patterns. Prior studies suggest that elevated depressive symptoms are associated with risk of mild cognitive impairment (MCI) and probable dementia, but whether affective states are associated with cognitive impairment is still unknown. The present study examined relationships between baseline affective states and cognitive impairment (MCI, probable dementia) in nondepressed women.

Method

Baseline PA and NA were assessed in postmenopausal women (N = 2,137; mean age = 73.8 years) from the Women's Health Initiative Study of Cognitive Aging (WHISCA) using the Positive and Negative Affect Schedule (PANAS). Women were followed annually for an average of 11.3 years; those with elevated depressive symptoms at baseline were excluded.

Results

Higher NA was associated with a higher risk of MCI and probable dementia, even after adjusting for important covariates including age, education, sociodemographic, lifestyle, and cardiovascular risk factors, global cognition, and hormone therapy assignment at baseline. PA was not significantly associated with either outcome.

Conclusions

We present the first evidence to date that greater NA, even in the absence of elevated depressive symptoms, is associated with higher risk of MCI and dementia. This suggests that NA may be an important, measureable and potentially modifiable risk factor for age-related cognitive decline.

Personality and Alzheimer's disease: An integrative review

The objective of this article is to review and integrate interrelated areas of research on personality and Alzheimer's disease (AD). Prospective studies indicate that individuals who score higher on conscientiousness (more responsible and self-disciplined) and lower on neuroticism (less anxious and vulnerable to stress) have a reduced risk of developing dementia, even in the presence of AD neuropathology. Personality is also related to measures of cognitive performance and cognitive decline, with effect sizes similar to those of other clinical, lifestyle, and behavioral risk factors. These associations are unlikely to be due to reverse causality: Long-term prospective data indicate that there are no changes in personality that are an early sign of the disease during the preclinical phase of AD. With the onset and progression of dementia, however, there are large changes in personality that are reported consistently by caregivers in retrospective studies and are consistent with the clinical criteria for the diagnosis of dementia. The review also discusses potential mechanisms of the observed associations and emphasizes the need for prospective studies to elucidate the interplay of personality traits with AD neuropathology (amyloid and tau biomarkers) in modulating the risk and timing of onset of clinical dementia. The article concludes with the implications of personality research for identifying those at greater risk of AD and the potential of personality-tailored interventions aimed at the prevention and treatment of AD. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Meta-Analysis of Personality Traits in Alzheimer's Disease: A Comparison with Healthy Subjects

BACKGROUND

The role of specific personality traits as factor risks of Alzheimer's disease (AD) has been consistently found, whereas personality traits specifically related to AD (after the diagnosis) have not been outlined yet.

OBJECTIVE

A meta-analysis of published studies was performed to determine whether AD patients have a distinctive personality trait profile compared to healthy subjects (HC), similar to or different from a premorbid personality profile consistently reported in previous studies.

METHODS

A systematic literature search was performed using PsycInfo (PROQUEST), PubMed, and Scopus. The meta-analysis pooled results from primary studies using Hedges' g unbiased approach.

RESULTS

The meta-analysis included 10 primary studies and revealed that, when the personality was evaluated by informant-rated measures, AD patients had significantly higher levels of Neuroticism, lower levels of Openness, Agreeableness, Conscientiousness, and Extraversion than HCs. When the personality was evaluated by self-rated measures, the results obtained from informants were confirmed for Neuroticism, Openness, and Extraversion but not for Agreeableness and Conscientiousness where AD patients and HCs achieved similar scores.

CONCLUSIONS

The meta-analysis revealed that high Neuroticism and low Openness and Extraversion are distinctive personality traits significantly associated with a diagnosis of AD when evaluated both self-rated and informant-rated measures. This personality trait profile is similar to premorbid one, which contributes to development of AD over time. Therefore, our findings indirectly support the idea of specific premorbid personality traits as harbingers of AD.

Depressive vulnerability in women with Alzheimer's disease: Relationship with personality traits and abnormal personality dimensions

BACKGROUND

This study sought to determine the evaluation of current and pre-morbid depressive vulnerability dimensions in Alzheimer's disease. Sidney Blatt´s personality developmental perspective, the Five-Factor model and Axis II personality disorders were taken as references.

METHODS

The study was conducted with two groups which were assessed using the Depressive Experiences Questionnaire, the NEO-FFI and the Personality Diagnostic Questionnaire-4+, in the form of individual interview sessions. Current personality measure: Alzheimer's disease Group, consisting of 44 female participants (M_Age= 81.36 years); Pre-morbid personality measure: Alzheimer's disease Group Informants (n = 40).

RESULTS

Self-Criticism personality vulnerability is a general indicator of psychopathology. In pre-morbidity, Neuroticism (β = 0.41), Agreeableness (β = -0.63) and Conscientiousness (β = -0.08) predicted Self-Criticism, explaining 64% of the variance; additionally, Self-Criticism (β = 0.72) and Neediness (β = 2.05) predicted the PDQ-4+ total, explaining 58% of the variance. In terms of current personality, the PDQ-4+ total was predicted by Self-Criticism (β = 0.55), explaining 30% of the variance.

LIMITATIONS

The small size of the samples, especially since it is difficult to access individuals diagnosed with AD at the onset or in its early stages; measuring personality changes by means of retrospective assessment by proxies may have introduced some memory bias.

CONCLUSIONS

These findings are relevant to research relating depressive vulnerability to personality traits and psychopathology in Alzheimer's disease.

Differences regarding the five-factor personality model in patients with subjective cognitive decline and mild cognitive impairment

Personality and dementia are connected in different ways. A broad knowledge about personality and prodromal stages of dementia might be helpful to identify dementia as early as possible. Hence, personality differences between three cognitively impaired groups on the basis of patients’ self-assessments of personality traits and connections between personality and cognitive functioning were examined via a cross-sectional study. The sample consisted of cognitively impaired patients (N = 133), aged 50 and older, who came to a memory clinic due to cognitive complaints. The test procedure encompassed a cognitive screening, the Neuropsychological Test Battery Vienna (NTBV), and self-assessment questionnaires such as the Big Five Plus One Persönlichkeitsinventar (B5PO). While patients with subjective cognitive decline (SCD) did not differ from those with non-amnestic mild cognitive impairment (naMCI) concerning the different personality traits, patients with amnestic mild cognitive impairment (aMCI) showed significantly lower scores for extraversion (p < 0.05), openness (p < 0.001), and empathy (p < 0.001) than patients with SCD as well as patients with naMCI. Thus, cognitively impaired groups mainly differ concerning personality traits depending on whether they do show memory decline or not.

Personality and its Relationship to Depression and Cognition in Older Adults: Implications for Practice

OBJECTIVES

Personality is an important contributor to an individual's mental health and is consistently linked to the two most prevalent mental health conditions among older adults: dementia and depression. This review summarizes the current findings on personality and its association with cognitive decline and depression, as well as treatment outcomes and possible intervention strategies.

METHODS

Literature searches were conducted in Web of Science, PubMed, and PsycINFO. Search terms included 'personality traits,' 'depression,' 'treatment,' and 'older adults.'

RESULTS

Cognitive decline and depressive disorders are both associated with a common personality profile: high neuroticism, and low conscientiousness, extraversion, openness, and agreeableness. Across studies, the most consistent predictor of late-life depression, its course, and treatment outcomes is higher neuroticism.

CONCLUSIONS

Personality traits are associated with cognitive decline, as well as the diagnosis and course of late-life depression in older adults. However, formal personality assessment is not typically incorporated in clients' treatment plans, even though personality traits may influence treatment efficacy and outcomes.

CLINICAL IMPLICATIONS

Formal assessment of personality traits may be beneficial in terms of treatment adherence and outcomes for older adults. Tailored interventions that specifically target the client's strengths are likely to be well received by both clients and clinicians.

[A Patient´s Personality: A Frequently Ignored but Important Component in General Medical Practice]

A Patient´s Personality: A Frequently Ignored but Important Component in General Medical Practice Abstract. In general medical practice, a patient's personality is hardly considered and assessed. In this mini-review the author summarises how a comprehensive personality assessment may provide valuable patient information. Prospective effects of personality traits on general lifestyle as well as mental and physical health are presented. In addition, original research is introduced that shows meaningful associations between personality traits, clinical disease markers, and all-cause mortality. These findings are discussed with respect to selected etiological models. The studies illustrate that a personality assessment could be a useful aid for diagnosis, prognosis, and treatment planning.

Personality and Suicidal Behavior in Old Age: A Systematic Literature Review

BACKGROUND

Suicide rates generally peak in the second half of life and are particularly high in older men; however, little is known about the contribution of dispositional factors to late-life suicide. Maladaptive personality traits have been strongly implicated in suicide among younger adults, but the extent to which they continue to play a role in late-life suicidal behavior is unclear. We also do not know whether specific personality profiles interact with the stressors of aging to cause suicidal behavior.

METHODS

We sought to synthesize the data on personality pathology in late-life suicidal ideation and behavior via a systematic review using the PubMed, Google Scholar, PsycInfo, Scopus, Ovid, Web of Science, Embase, and Cochrane search engines. The included key words related to three descriptors: "personality," "suicide," and "elderly." Included articles evaluated personality based on the Five-Factor Model (FFM) or ICD/DSM diagnostic criteria in older samples with minimum age cutoffs of 50 years or older. Our original search identified 1,183 articles, of which 31 were retained.

RESULTS

Included studies were heterogeneous in their design and personality measurements. Studies of categorical personality disorders were particularly scarce and suggested a stronger association with late-life suicidal ideation than with death by suicide. Only obsessive-compulsive and avoidant personality traits were associated with death by suicide in old age, but only in studies that did not control for depression. All personality constructs were positively linked to suicidal ideation, except for histrionic personality, which emerged as a negative predictor. Studies employing the FFM also indicated that older adults who died by suicide were less likely to display a maladaptive personality profile than elderly suicide attempters and younger suicide victims, having both lower levels of neuroticism and higher levels of conscientiousness than these comparison groups. Nevertheless, older suicide victims displayed lower levels of openness to experience than younger victims in two samples.

CONCLUSION

Maladaptive personality manifests in milder, subthreshold, and more heterogeneous forms in late-life vs. early-life suicide. An inability to adapt to the changes occurring in late life may help explain the association between suicide in old age and higher conscientiousness as well as obsessive-compulsive and avoidant personality disorders.

Facets of Conscientiousness and risk of dementia

BACKGROUND

Multiple studies have found Conscientiousness to be protective against dementia. The purpose of this study is to identify which specific aspects, or facets, of Conscientiousness are most protective against cognitive impairment and whether these associations are moderated by demographic factors and/or genetic risk.

METHODS

Health and Retirement Study participants were selected for analysis if they completed the facets of Conscientiousness measure, scored in the range of normal cognitive functioning at the baseline personality assessment, and had at least one follow-up assessment of cognition over the up to 6-year follow-up (N = 11 181). Cox regression was used to test for risk of incident dementia and risk of incident cognitive impairment not dementia (CIND).

RESULTS

Over the follow-up, 278 participants developed dementia and 2186 participants developed CIND. The facet of responsibility had the strongest and most consistent association with dementia risk: every standard deviation increase in this facet was associated with a nearly 35% decreased risk of dementia; self-control and industriousness were also protective. Associations were generally similar when controlling for clinical, behavioral, and genetic risk factors. These three facets were also independent predictors of decreased risk of CIND.

CONCLUSIONS

The present research indicates that individuals who see themselves as responsible, able to control their behavior, and hard workers are less likely to develop CIND or dementia and that these associations persist after accounting for some common clinical, behavioral, and genetic risk factors.

Self-reported personality traits are prospectively associated with proxy-reported behavioral and psychological symptoms of dementia at the end of life

OBJECTIVE

Behavioral and psychological symptoms of dementia (BPSD) are among the most challenging aspects of Alzheimer disease for patients and their families. Previous studies have found associations between informant-reported retrospective personality and BPSD; we test whether prospective, self-reported personality predicts who will experience these symptoms.

METHODS

Deceased participants from the Health and Retirement Study who had evidence of cognitive impairment at the end of life (N = 1988) were selected to examine whether self-reported five-factor model personality traits, measured up to 8 years before death, were associated with proxy-reported BPSD.

RESULTS

Neuroticism was associated with increased risk of the 7 BPSD: got lost in familiar places, wandered off, were not able to be left alone, experienced hallucinations, suffered from depression, had periodic confusion, and an uncontrolled temper. These associations were not moderated by age, gender, race, or education. Conscientiousness was associated with fewer symptoms overall and especially with lower risk of getting lost in familiar places and not being able to be left alone.

CONCLUSIONS

The present research indicates that self-reported personality, particularly Neuroticism, is associated prospectively with risk for a wide range of behavioral symptoms for individuals who had cognitive impairment at the end of life. The use of self-reported personality traits can help aid in identifying who is most at risk for behavioral symptoms. Such information may be useful for nonpharmacological interventions tailored to the individual's personality to reduce the prevalence and burden of these BPSD.