Personality changes in Alzheimer's disease: a systematic review

Risk-Taking Behavior Differs Between Older Adults with and without Mild Cognitive Impairment

Background

Adequately evaluating risk and making decisions is vital but understudied for older adults living independently but with compromised cognition, as seen in those with mild cognitive impairment (MCI), specifically those with amnestic MCI (aMCI) which is associated with higher risk of conversion to Alzheimer's disease.

Objective

We propose to comprehensively evaluate risk-taking behaviors across domains important for everyday activities between an aMCI group and their cognitively healthy counterparts (HC).

Methods

A case-control study design. Data on risk-taking behaviors via the Domain-Specific Risk-Taking Scale (DOSPERT), and candidate confounding mental health factors (i.e., neurodegeneration, depression, and fatigue) were collected. Analyses on group difference and interaction between group and confounding factors on risk-taking behaviors were conducted.

Results

The aMCI group showed a higher likelihood of risk-taking than HC (t = 4.38, df = 73, p < 0.001). Moderation analysis showed fatigue (F = 5.91, p = 0.018) and presence of depression (F = 4.52, p = 0.037), but not neurodegeneration, as significant moderators for group and DOSPERT total score, controlling for sex. In post-hoc analyses, there was a significant relationship between both fatigue (B = -7.83, SE = 3.65, t = -2.14, p = 0.036), and presence of depression (B = -20.80, SE = 9.97, t = -2.09, p = 0.041), with DOSPERT total score for HC but not for aMCI. There were no significant relationships between neurodegeneration, fatigue, or depression with any specific risk-taking domains after correction for multiple comparisons.

Conclusions

Our results show differences in risk-taking behavior between older adults with and without intact cognition, and overall decision-making is affected by fatigue and depression in HC but not aMCI, together suggesting the importance of cognition in the ability to adjust risk-taking behaviors.

Improving preclinical to clinical translation of cognitive function for aging-related disorders: the utility of comprehensive touchscreen testing batteries in common marmosets

Concerns about poor animal to human translation have come increasingly to the fore, in particular with regards to cognitive improvements in rodent models, which have failed to translate to meaningful clinical benefit in humans. This problem has been widely acknowledged, most recently in the field of Alzheimer's disease, although this issue pervades the spectrum of central nervous system (CNS) disorders, including neurodevelopmental, neuropsychiatric, and neurodegenerative diseases. Consequently, recent efforts have focused on improving preclinical to clinical translation by incorporating more clinically analogous outcome measures of cognition, such as touchscreen-based assays, which can be employed across species, and have great potential to minimize the translational gap. For aging-related research, it also is important to incorporate model systems that facilitate the study of the long prodromal phase in which cognitive decline begins to emerge and which is a major limitation of short-lived species, such as laboratory rodents. We posit that to improve translation of cognitive function and dysfunction, nonhuman primate models, which have conserved anatomical and functional organization of the primate brain, are necessary to move the field of translational research forward and to bridge the translational gaps. The present studies describe the establishment of a comprehensive battery of touchscreen-based tasks that capture a spectrum of domains sensitive to detecting aging-related cognitive decline, which will provide the greatest benefit through longitudinal evaluation throughout the prolonged lifespan of the marmoset.

Informant-rated change in personality traits, psychological distress, well-being, and social connection with dementia

OBJECTIVES

Studies of retrospective personality change with dementia consistently find caregivers report large changes in personality (e.g., increases in neuroticism) of their care recipients compared to before dementia. This work seeks to replicate the established pattern of personality change, extend it to change in psychological distress, well-being, and social connection, and evaluate whether changes vary by stage of dementia.

METHODS

Caregivers of people with dementia (N = 188) reported on the psychological and social health of their care recipient currently and how they were before they developed dementia. Personality was measured as five factor model traits. Psychological distress was measured as symptoms of depression and anxiety, perceived stress, and pessimism. Psychological well-being was measured as purpose in life, life satisfaction, happiness, self-efficacy, and optimism. Social connection was measured as loneliness, belonging, social support, and social strain.

RESULTS

There were substantial increases in neuroticism (d = 1.14) and decreases in the other four personality traits (d range=-0.85 to -1.37). There were significant increases in psychological distress (e.g., d = 1.07 for depression) and substantial decreases in well-being (e.g., d=-1.18 for purpose in life) and social connection (e.g., d=-1.12 for belonging). Change was apparent across dementia stage and generally larger in more severe dementia.

DISCUSSION

In addition to personality, there are large retrospective changes in psychological distress, well-being, and social connection with dementia. These quantitative findings complement clinical observations of the natural history of psychosocial changes in people with dementia, and can inform families, clinicians, and researchers on commonly observed changes and improve interventions to mitigate dementia burden.

Machine learning-based classification of Alzheimer's disease and its at-risk states using personality traits, anxiety, and depression

BACKGROUND

Alzheimer's disease (AD) is often preceded by stages of cognitive impairment, namely subjective cognitive decline (SCD) and mild cognitive impairment (MCI). While cerebrospinal fluid (CSF) biomarkers are established predictors of AD, other non-invasive candidate predictors include personality traits, anxiety, and depression, among others. These predictors offer non-invasive assessment and exhibit changes during AD development and preclinical stages.

METHODS

In a cross-sectional design, we comparatively evaluated the predictive value of personality traits (Big Five), geriatric anxiety and depression scores, resting-state functional magnetic resonance imaging activity of the default mode network, apoliprotein E (ApoE) genotype, and CSF biomarkers (tTau, pTau181, Aβ42/40 ratio) in a multi-class support vector machine classification. Participants included 189 healthy controls (HC), 338 individuals with SCD, 132 with amnestic MCI, and 74 with mild AD from the multicenter DZNE-Longitudinal Cognitive Impairment and Dementia Study (DELCODE).

RESULTS

Mean predictive accuracy across all participant groups was highest when utilizing a combination of personality, depression, and anxiety scores. HC were best predicted by a feature set comprised of depression and anxiety scores and participants with AD were best predicted by a feature set containing CSF biomarkers. Classification of participants with SCD or aMCI was near chance level for all assessed feature sets.

CONCLUSION

Our results demonstrate predictive value of personality trait and state scores for AD. Importantly, CSF biomarkers, personality, depression, anxiety, and ApoE genotype show complementary value for classification of AD and its at-risk stages.

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.

Informant-rated change in personality traits, psychological distress, well-being, and social connection with dementia

Objectives

Studies of retrospective personality change with dementia consistently find caregivers report large changes in personality (e.g., increases in neuroticism) of their care recipients compared to before dementia. This work seeks to replicate the established pattern of personality change, extend it to change in psychological distress, well-being, and social connection, and evaluate whether changes vary by stage of dementia.

Methods

Caregivers of people with dementia (N=194) reported on the psychological and social health of their care recipient currently and how they were before they developed dementia. Personality was measured as five factor model traits. Psychological distress was measured as symptoms of depression and anxiety, perceived stress, and pessimism. Psychological well-being was measured as purpose in life, life satisfaction, happiness, self-efficacy, and optimism. Social connection was measured as loneliness, belonging, social support, and social strain.

Results

There were substantial increases in neuroticism (d=1.10) and decreases in the other four personality traits (d range=-.82 to -1.31). There were significant increases in psychological distress (e.g., d=1.05 for depression) and substantial decreases in well-being (e.g., d=-1.07 for purpose in life) and social connection (e.g., d=-1.09 for belonging). Change was apparent across dementia stage and generally larger in more severe dementia.

Discussion

In addition to personality, there are large retrospective changes in psychological distress, well-being, and social connection with dementia. These quantitative findings complement clinical observations of the natural history of psychosocial changes in people with dementia, and can inform families, clinicians, and researchers on commonly observed changes and improve interventions to mitigate dementia burden.

The associations between personality traits and quality of life, satisfaction with life, and well-being over time in people with dementia and their caregivers: findings from the IDEAL programme

BACKGROUND

Cross-sectional evidence indicates that certain personality traits may influence how well people with dementia and their caregivers are able to live alongside the condition. However, no studies to date have explored these associations longitudinally. The present study aimed to explore whether each of the Five-Factor personality traits were associated with change over two years in perceptions of 'living well' for people with dementia and their caregivers. 'Living well' was conceptualized as a composite of quality of life, satisfaction with life, and subjective well-being.

METHODS

Data were analyzed from 1487 people with dementia and 1234 caregivers who took part in the IDEAL cohort. Participants were categorized into low, medium, and high groups for each trait using stanine scores. Latent growth curve models investigated associations between these groups and 'living well' scores for each trait at baseline and at 12 and 24 months. Covariates included cognition in people with dementia and stress in caregivers. A Reliable Change Index was calculated against which to evaluate changes in 'living well' scores over time.

RESULTS

At baseline, neuroticism was negatively associated with 'living well' scores for people with dementia, while conscientiousness, extraversion, openness, and agreeableness were positively associated. For caregivers, neuroticism was negatively associated with 'living well' scores at baseline while conscientiousness and extraversion were positively associated. 'Living well' scores were mostly stable over time with no influence of personality traits on observed changes.

CONCLUSIONS

Findings suggest that personality traits, particularly neuroticism, have a meaningful impact on how people with dementia and caregivers rate their capability to 'live well' at baseline. Over time 'living well' scores for each personality trait group were largely stable. Studies utilizing longer follow-up periods and more appropriate measures of personality are needed to corroborate and extend the findings of the present study.

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.

Changes in personality traits in patients with Alzheimer's Disease

Changes in personality traits in patients with Alzheimer's disease (AD) are extremely common throughout the course of the pathology, and these behavioral changes present themselves as challenges in clinical management and as a significant cause of caregivers’ burden.

Elderly Helping Other Elderly: A Comparative Study of Family Caregiver Burden Between Patients With Dementia or Cancer at the End of Life

A new reality is being observed around the world as the population ages: family caregivers, who are themselves older adults helping their ill older relatives. The aim of this study is to assess the burden of the older family caregiver assisting older patients in his or her end-of-life who are suffering from dementia or cancer. In this context, the elderly person is involved in the dual role of patient and caregiver. In this comparative study, a total of 87 older family caregivers (age ≥ 65 years) completed the Caregiver Burden Inventory (CBI) measurement. The sample was divided into 2 subgroups based on the individuals' advanced disease: Alzheimer's disease (AD) or cancer. Compared to cancer caregivers, the AD subgroup reported significantly higher scores in the CBI-emotional subscale (P = 0.006), confirmed by the evaluation of the generalized linear model (multivariate). There were no significant differences in the other CBI subscales and overall scores. According to the findings of this study, elderly who help elderly with AD are at a higher risk of experiencing an emotional burden than cancer caregivers. This data could be considered in designing interventions to reduce the caregiver burden of older family caregivers as they provide informal end-of-life care.

Traditional Uses, Phytochemical Constituents and Pharmacological Properties of Averrhoa carambola L.: A Review

Averrhoa carambola L. (star fruit) is an edible fruit that is extensively cultivated in southern China, Southeast Asia, India, and northern South America. It has a sweet and juicy taste and is frequently used in fruit salads and fruit platters, as a garnish in cocktail drinks and beverages, or squeezed into juice and served as a beverage. Traditionally, it has been used for treating diabetes and diabetic nephropathy, arthralgia, vomiting, lithangiuria, coughing, hangovers, and chronic paroxysmal headache for thousands of years. Currently, approximately 132 compounds have been isolated from A. carambola. Among them, flavonoids, benzoquinone, and their glycosides have been considered as biologically active substances, which are responsible for various biological activities. Pharmacological studies have revealed that crude extracts or monomeric compounds from A. carambola exhibit multiple bioactivities, such as anti-oxidant, anti-hyperglycemic, anti-obesity, anti-hyperlipidemic, anti-tumor, anti-inflammatory, hepatoprotective, cardioprotective, anti-hypertensive, neuroprotective, and others. Thus, A. carambola is a valuable treatment in Chinese medicine with therapeutic potential for multiple diseases, especially diabetes and diabetes-related diseases. Even though it is a very promising candidate in the development of functional food and the pharmaceutical industry, reports on its bioactivities have only been conducted in vivo and in vitro and there is a gap in research regarding clinical settings and safety. This review therefore provides a comprehensive and systematic overview of current progress on botany, ethnopharmacology, phytochemistry, pharmacology, and toxicity of A. carambola, providing a valuable reference for further developments and applications of A. carambola in the pharmaceutical industry and functional food.

Assessing the Effects of Healthy and Neuropathological Aging on Personality with the Iowa Scales of Personality Change

Personality changes in older adults with brain disease may be confounded by effects of normal aging. In this cross-sectional study, ratings with the Iowa Scales of Personality Change for 62 healthy older adults (OA-H, aged 60+) were compared to matched older adults with brain diseases (OA-BD). OA-H did not show any significant personality changes from middle age to older adulthood. However, between 10% and 20% of OA-H developed a disturbance in Lack of Stamina, Inflexibility, Lability, and Lack of Insight. Otherwise, the pattern of findings suggesting normal aging effects on personality disturbances in clinical groups are generally minimal.

Mortality in patients with behavioural and psychological symptoms of dementia: a registry-based study

OBJECTIVES

Behavioural and psychological symptoms of dementia (BPSD) are common in patients with dementia. In the elderly population, comorbidities frequently coexist with dementia and mortality in dementia is high. The aim of this study was to investigate the impact of BPSD on mortality in severe dementia.

METHODS

This study of 11,448 individuals was based on linked information from the Swedish BPSD registry, the National Patient Register and the Cause of Death register. BPSD was assessed with the Neuropsychiatric Inventory (NPI). Cox proportional hazards regressions were performed for survival analysis. To study different degrees of BPSD, data was categorized into groups: no (NPI, 0 points), mild (NPI, 1-3 points on ≥1 item), moderate (NPI, 4-8 points on ≥1 item) and severe (NPI, 9-12 points on ≥1 item) BPSD based on the highest score on any of the BPSD assessed (NPI items).

RESULTS

The presence of moderate or severe BPSD was associated with a stepwise increased risk of mortality (hazard ratio (HR), 1.31; 95% confidence interval (CI), 1.08-1.60 and HR 1.74; 95% CI 1.44-2.12, respectively) compared with individuals with no BPSD. In addition, there was an association between total NPI score and mortality (HR 1.01; 95% CI 1.007-1.010). The results remained significant after multivariable adjustment for age, sex, dementia diagnosis, medication, previous myocardial infarction, hip fracture and stroke.

CONCLUSIONS

The results show a stepwise increase in mortality risk with increased BPSD, highlighting the importance of adequate management of BPSD to reduce mortality in dementia.

The role of loneliness in the development of depressive symptoms among partnered dementia caregivers: Evidence from the English Longitudinal Study of Aging

Background

Depressive symptoms are highly prevalent among partnered dementia caregivers, but the mechanisms are unclear. This study examined the mediating role of loneliness in the association between dementia and other types of care on subsequent depressive symptoms.

Methods

Prospective data from partnered caregivers were drawn from the English Longitudinal Study of Aging. The sample consisted of 4,672 partnered adults aged 50–70 living in England and Wales, followed up between 2006–2007 and 2014–2015. Caregiving was assessed across waves 3 (2006–2007), 4 (2008–2009), and 5 (2010–2011), loneliness at wave 6 (2012–2013), and subsequent depressive symptoms at wave 7 (2014–15). Multivariable logistic regression models were used to assess the association between caregiving for dementia and depressive symptoms compared to caregiving for other illnesses (e.g., diabetes, coronary heart disease (CHD), cancer, and stroke). Binary mediation analysis was used to estimate the indirect effects of caregiving on depressive symptoms via loneliness.

Results

Care for a partner with dementia was associated with higher odds of depressive symptoms at follow-up compared to those not caring for a partner at all (odds ratio [OR] = 2.6, 95% confidence intervals [CI]: 1.4, 5.1). This association was partially mediated by loneliness (34%). Care for a partner with other conditions was also associated with higher odds of depressive symptoms compared to non-caregiving partners (OR = 1.7, 95% CI: 1.2, 2.5), but there was no evidence of an indirect pathway via loneliness.

Conclusion

Loneliness represents an important contributor to the relationship between dementia caregiving and subsequent depressive symptoms; therefore, interventions to reduce loneliness among partnered dementia caregivers should be considered.

Interactions between Personality, Depression, Anxiety and Cognition to Understand Early Stage of Alzheimer's Disease

The multifaceted nature of Alzheimer's disease (AD) and Mild cognitive impairment (MCI) can lead to wide inter-individual differences in disease manifestation in terms of brain pathology and cognition. The lack of understanding of phenotypic diversity in AD arises from a difficulty in understanding the integration of different levels of network organization (i.e. genes, neurons, synapses, anatomical regions, functions) and in inclusion of other information such as neuropsychiatric characteristics, personal history, information regarding general health or subjective cognitive complaints in a coherent model. Non-cognitive factors, such as personality traits and behavioral and psychiatric symptoms, can be informative markers of early disease stage. It is known that personality can affect cognition and behavioral symptoms. The aim of the paper is to review the different types of interactions existing between personality, depression/anxiety, and cognition and cognitive disorders at behavioral and brain/genetic levels.

Challenges related to providing care for parents with dementia across borders: A qualitative study on transnational carers in Oslo

Migration requires people to re-define their caring roles, develop new caring strategies and negotiate the scope of care with the family in the country of origin. The main aim of this paper is to identify and describe challenges related to transnational care provided for people with dementia. Transnational caring itself poses many challenges for families but caring for a person living with dementia can be especially difficult. The qualitative data presented in this article was collected in 2018 as part of a larger study focusing on understandings, experiences and responses to age-related cognitive impairment among families with minority ethnic backgrounds. The data includes seven semi-structured in-depth interviews with migrants in Oslo who were engaged in transnational caring activities for their parents living with dementia. The participants in our study experienced numerous challenges related to providing care across borders to their parents. Some of the challenges were typical for transnational caring and were associated with care regimes in the countries of parents' and participants' residence, motives for providing care, participants' socio-economic situation and family relations. The other challenges were due to specific care needs of people living with dementia.

Personality determinants of subjective executive function in older adults

Objectives: Problems in subjective executive function, the perceived cognitive control of mental processes for goal-directed behavior, may indicate cognitive impairment in older adulthood. Although, previous studies highlight the importance of personality on objective cognitive performance, no studies clarify their role with subjective executive function. To inform methods of early identification of cognitive impairment, this study explored how temperament and personality traits account for problems in subjective executive function.Method: The current project examined the associations between temperament and personality on subjective executive function across two samples of community-dwelling older adults (65+ years, n₁ = 25, n₂ = 50). Both studies measured subjective executive function (Behavioral Rating Inventory of Executive Function-Adult) and separately administered scales on temperament (Adult Temperament Questionnaire) and personality (Big Five Inventory).Results: Concerning temperament, older adults higher in negative affect endorsed greater difficulty in subjective executive function. Regarding personality traits, older adults with higher neuroticism and lower conscientiousness reported higher difficulty in subjective executive function.Conclusion: Findings enhance our understanding of subtle cognitive changes and may aid in early detection. In particular, distressful inclinations were associated with more reported problems in executive function whereas problem-solving tendencies were inversely related. Future work should examine if enhanced negativity coupled with analytical disengagement predicts problems in subjective executive function over time.

MicroRNA-338-5p alleviates neuronal apoptosis via directly targeting BCL2L11 in APP/PS1 mice

MicroRNAs have become pivotal modulators in the pathogenesis of Alzheimer’s disease. MiR-338-5p is associated with neuronal differentiation and neurogenesis, and expressed aberrantly in patients with cognitive dysfunction. However, its role and potential mechanism involved in Alzheimer’s disease remain to be elucidated. Herein, we showed that the expression of miR-338-5p decreased in APP/PS1 mice, accompanied by the elevation in the expression level of amyloid β, which indicated a reverse relationship between Alzheimer’s disease progression and miR-338-5p. In addition, lentiviral overexpression of miR-338-5p through intrahippocampal injection mitigated the amyloid plaque deposition and cognitive dysfunction in APP/PS1 mice, suggesting a protecting role of miR-338-5p against the development of Alzheimer’s disease. Moreover, miR-338-5p decelerated apoptotic loss of neurons in APP/PS1 mice. MiR-338-5p decreased neuronal apoptosis in vitro induced by amyloid β accumulation, which was attributed to the negative regulation of BCL2L11 by miR-338-5p, since the restoration of BCL2L11 eliminated the protective role of miR-338-5p against neuronal apoptosis. Taken together, all of these results may indicate miR-338-5p as an innovative modulator in the pathogenesis of Alzheimer’s disease, and also suggest that the protective effect of miR-338-5p on neuronal apoptosis may underlie its beneficial effect on APP/PS1 mice.

Personality as a Resource for Labor Market Participation among Individuals with Chronic Health Conditions

Background: The link between personality traits and employment status in individuals with chronic health conditions (CHCs) is largely unexplored. In this study, we examined this association among 21,173 individuals with CHCs and whether this association differs between individuals suffering from a heart disease, depression, anxiety, cancer, chronic obstructive pulmonary disease, musculoskeletal disease (MSD) and type 2 diabetes mellitus (T2DM). Methods: This study was conducted using baseline data from the Lifelines Cohort Study. Employment status and the presence of CHCs were determined by questionnaire data. The Revised Neuroticism-Extroversion-Openness Personality Inventory (NEO-PI-R) was used to measure eight personality facet traits. We conducted disease-generic and disease-specific logistic regression analyses. Results: Workers with higher scores on self-consciousness (OR: 1.02; 95% CI: 1.01-1.02), impulsivity (1.03; 1.02-1.04), excitement seeking (1.02; 1.01-1.02), competence (1.08; 1.07-1.10) and self-discipline (1.04; 1.03-1.05) were more often employed. Adults with higher scores on anger-hostility (0.97; 0.97-0.98), vulnerability (0.98; 0.97-0.99), and deliberation (0.96; 0.95-0.97) were least often employed. Personality facets were associated strongest with employment status among individuals suffering from MSD and weakest in individuals with T2DM. Conclusions: Personality might be a key resource to continue working despite having a CHC. This may be relevant for the development of targeted personality-focused interventions.

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.

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.

Personality factors and cerebral glucose metabolism in community-dwelling older adults

Personality factors have been associated with Alzheimer's disease (AD) and dementia, but they have not been examined against markers of regional brain glucose metabolism (a primary measure of brain functioning) in older adults without clinically diagnosed cognitive impairment. The relationship between personality factors derived from the five-factor model and cerebral glucose metabolism determined using positron emission tomography (PET) with [18F]-2-fluoro-2-deoxy-D-glucose (18F-FDG-PET) was examined in a cohort of 237 non-demented, community-dwelling older adults aged 60-89 years (M ± SD = 73.76 ± 6.73). Higher neuroticism and lower scores on extraversion and conscientiousness were significantly associated with decreased glucose metabolism in brain regions typically affected by AD neuropathological processes, including the hippocampus and entorhinal cortex. Furthermore, while there were significant differences between apolipoprotein E (APOE) ε4 allele carriers and non-carriers on ¹⁸F-FDG-PET results in the neocortex and other brain regions (p < 0.05), there was no significant difference between carriers and non-carriers on personality factors and no significant interactions were found between APOE ε4 carriage and personality factors on brain glucose metabolism. In conclusion, we found significant relationships between personality factors and glucose metabolism in neural regions more susceptible to AD neuropathology in older adults without clinically significant cognitive impairment. These findings support the need for longitudinal research into the potential mechanisms underlying the relationship between personality and dementia risk, including measurement of change in other AD biomarkers (amyloid and tau imaging) and how they correspond to change in personality factors. Future research is also warranted to determine whether timely psychological interventions aimed at personality facets (specific aspects or characteristics of personality factors) can affect imaging or other biomarkers of AD resulting in delay or ideally preventing the onset of the cognitive impairment.

Personality of late- and early-onset elderly suicide attempters

OBJECTIVES

While suicidal behavior often manifests in adolescence and early adulthood, some people first attempt suicide in late life, often with remarkable lethal intent and determination. Given these individuals' more adaptive functioning earlier in life, they may possess traits that hinder adjustment to aging, such as high conscientiousness, rather than impulsive-aggressive traits associated with suicidal behavior in younger adults.

METHODS

A cross-sectional case-control study was conducted in older adults aged ≥50 (mean: 65), divided into early- and late-onset attempters (age at first attempt ≤ or >50, mean: 31 vs 61), suicide ideators as well as non-suicidal depressed and healthy controls. Personality was assessed in terms of the five-factor model (FFM, n = 200) and five DSM personality disorders analyzed on the trait level as continuous scores (PDs, n = 160). Given our starting hypothesis about late-onset attempters, the FFM dimension conscientiousness was further tested on the subcomponent level.

RESULTS

All clinical groups displayed more maladaptive profiles than healthy subjects. Compared to depressed controls, higher neuroticism, and borderline traits characterized both suicide ideators and early-onset attempters, while only early-onset attempters further displayed lower extraversion and higher antisocial traits. Late-onset attempters were similar to depressed controls on most measures, but scored higher than them on orderliness, a conscientiousness subcomponent.

CONCLUSIONS

While neuroticism, introversion, and cluster B traits are prominent in early-onset suicidal behavior, late-onset cases generally lack these features. In contrast, higher levels of orderliness in late-onset suicidal behavior are compatible with the age-selective maladjustment hypothesis. Key points Personality of elderly attempters differed between those with early- and late-onset first attempts. Early-onset attempters possessed personality traits generally found in younger suicidal populations (high neuroticism, low extraversion, antisocial, and borderline PD traits), supporting that constitutional suicide risk factors persist into late life in some individuals. Late-onset suicide attempters had higher levels of orderliness than non-suicidal depressed participants, suggesting that this generally adaptive trait may facilitate suicidal behavior in a subset of depressed elderly.

The predictive power of personality through psychopathology in Alzheimer's disease: a control study of self-report and baseline retrospective assessment

Although there is a growing body of literature on the Alzheimer's disease (AD) personality changes, its relationships with personality disorders are still largely understudied. The relationships between the Five-Factor Model and the Axis II personality disorders were explored in the context of current and baseline personality in AD. The study was conducted with four groups who were administered the NEO-FFI and the PDQ-4+, mainly in interview sessions. Self-report measurement: AD Group, 40 female participants (M = 81.48 years); Control Group, 47 female participants from the population at large (M = 76.81 years). Baseline retrospective measurement: AD Group Informants (n = 40); Control Group Informants (n = 47). Three logistic regressions were computed. The baseline Neuroticism moderates the Neuroticism in the current clinical state. High Neuroticism, low Openness, high Cluster B, and baseline high Neuroticism, predicted the presence of AD diagnosis, accounting for 85% of the variance. In order to increase sensitivity towards an earlier diagnosis in AD, future empirically-based research should take into account an assessment set of structural personality variables.

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.

Association Between High School Personality Phenotype and Dementia 54 Years Later in Results From a National US Sample

IMPORTANCE

Personality phenotype has been associated with subsequent dementia in studies of older adults. However, neuropathologic changes often precede cognitive symptoms by many years and may affect personality itself. Therefore, it is unclear whether supposed dementia-prone personality profiles (high neuroticism and low conscientiousness) are true risk factors or merely reflections of preexisting disease.

OBJECTIVES

To examine whether personality during adolescence-a time when preclinical dementia pathology is unlikely to be present-confers risk of dementia in later life and to test whether associations could be accounted for by health factors in adolescence or differed across socioeconomic status (SES).

DESIGN, SETTING, AND PARTICIPANTS

Cohort study in the United States. Participants were members of Project Talent, a national sample of high school students in 1960. Individuals were identified who received a dementia-associated International Classification of Diseases, Ninth Revision (ICD-9) diagnosis code during any year between 2011 and 2013. The dates of our analysis were March 2018 to May 2019.

EXPOSURES

Ten personality traits were measured by the 150-item Project Talent Personality Inventory. Socioeconomic status was measured by a composite based on parental educational level, income, occupation, and property ownership. Participants were also surveyed on demographic factors and height and weight.

MAIN OUTCOMES AND MEASURES

Medicare records were collected, with dementia diagnoses in the period of 2011 to 2013 classified according to the US Centers for Medicare & Medicaid Services ICD-9-based algorithm. Cox proportional hazards regression models estimated the relative risk of dementia based on the 10 personality traits, testing interactions with SES and adjusting for demographic confounders.

RESULTS

The sample of 82 232 participants was 50.1% female, with a mean (SD) age of 15.8 (1.7) years at baseline and 69.5 (1.2) years at follow-up. Lower risk of dementia was associated with higher levels of vigor (hazard ratio for 1 SD, 0.93; 95% CI, 0.90-0.97; P < .001). Calm and maturity showed protective associations with later dementia that increased with SES. At 1 SD of SES, calm showed a hazard ratio of 0.89 (95% CI, 0.84-0.95; P < .001 for the interaction) and maturity showed a hazard ratio of 0.90 (95% CI, 0.85-0.96; P = .001 for the interaction).

CONCLUSIONS AND RELEVANCE

This study's findings suggest that the adolescent personality traits associated with later-life dementia are similar to those observed in studies of older persons. Moreover, the reduction in dementia risk associated with a calm and mature adolescent phenotype may be greater at higher levels of SES. Personality phenotype may be a true independent risk factor for dementia by age 70 years, preceding it by almost 5 decades and interacting with adolescent socioeconomic conditions.

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.

Mental Disorders in Young Adults from Families with the Presenilin-1 Gene Mutation E280A in the Preclinical Stage of Alzheimer's Disease

BACKGROUND

There are forms of Alzheimer's disease (AD) that have an autosomal dominant inheritance pattern; one of them is caused by the E280A mutation in the gene that codes for Presenilin-1 (PSEN1). Studying families of people with this mutation allows the evaluation of characteristics of the subjects before cognitive decline begins.

OBJECTIVE

To determine whether having the mutation E280A in PSEN1 increases the risk of presenting mental disorders in adults under 30 years old who are in the preclinical stage of AD and may be eligible for primary prevention studies of AD.

METHODS

A psychiatric evaluation was made to 120 people belonging to families with a history of early onset AD. Of these, 62 carried the E280A mutation in PSEN1. The occurrence of mental disorders between carriers and non-carriers of the mutation was compared.

RESULTS

No statistically significant differences were found in the frequency of any mental disorder between the group of carriers and non-carriers of the mutation (Hazard Ratio: 0.80, 95% CI 0.49 to 1.31); nor were differences observed when evaluating specific disorders.

CONCLUSION

The E280A mutation does not increase the risk of mental disorders before the age of 30 in the relatives of people affected by familial AD. Studies with larger sample sizes are required to assess the risk of low incidence mental disorders.

WITHDRAWN: Mental Disorders in Young Adults from Families with the Presenilin-1 Gene Mutation E280A in the Preclinical Stage of Alzheimer's Disease

Ahead of Print article withdrawn by publisher.

Proteomic analysis reveals the potential neuroprotective effects of tetramethylpyrazine dimer in neuro2a/APPswe cells

Alzheimer's disease (AD) is a common neurodegenerative disease characterized by pathological processes, including abnormal amyloid deposits and filament tangles, oxidative stress, neuroinflammation, and neurotrophic insufficiency, leading to chronic and prolonged neuronal loss and cognitive deficits. Tetramethylpyrazine (TMP) is one of the main active components of Ligusticum wallichii, a traditional Chinese medicine widely used for brain related disease. Here, we synthesized the TMP derivative tetramethylpyrazine dimer (DTMP), and evaluated the potential mechanisms underlying its potential neuroprotective effects using the murine neuron-like cells (N2a) transfected with the human "Swedish" mutant amyloid precursor protein (N2aAPP). ELISA results indicated that DTMP reduced the levels of Aβ1-40 and Aβ1-42 in N2aAPP. Then through proteomic analysis we identified a total of 208 differentially expressed proteins in N2aAPP cells compared to the wild-type N2a cells (N2aWT), including 144 increased and 64 decreased proteins. 449 differentially expressed proteins were revealed in N2aAPP cells on DTMP treatment with 69 increased and 380 decreased proteins. Bioinformatic analysis suggested that these proteins are enriched in mitochondrial function, the electronic transmission chain, ATP binding, oxidative phosphorylation, GTPase function, the transcriptional translation process, amino acid metabolism, nucleotide binding and others. Given the vital role of mitochondria in the pathogenesis of AD, we selected the electron transport chain pathway-related molecules to further validate these findings. Western-blot analysis demonstrated that DTMP significantly increased the levels of complex I (NDUAA), complex II (SDHB), complex III (UCRI), complex IV (COX5A) and complex V (ATP5A) in N2aAPP cells. The modulation of dysregulated proteins implicated in AD pathogenesis implies the pharmacological mechanisms of DTMP and its potential as a novel therapeutic choice in AD.

Stress and Alzheimer's disease

Alzheimer's disease (AD) is the leading cause of dementia worldwide. Due to demographic change in higher income countries and rising life expectancy in middle- and low-income countries, the prevalence of AD will increase significantly in the coming years. In the search for effective AD prevention, the role of stress in the development of AD has come into focus. There is increasing evidence that chronic exposure to stress is a risk factor for AD and may also adversely affect the course of the disease. In our review, we present the current literature on the association of specific personality traits and the risk of developing AD. We also report on findings on dementia risk in patients with posttraumatic stress disorder. Furthermore, we describe the role of anxiety symptoms in AD and give a brief overview over the biological mechanisms behind the association of stress and AD.

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.

Personality Changes With Dementia From the Informant Perspective: New Data and Meta-Analysis

OBJECTIVE

To examine changes in personality in individuals with mild cognitive impairment (MCI) or dementia as observed by family members using both new data and a meta-analysis with the published literature.

DESIGN

Current and retrospective personality assessments of individuals with dementia by family informants. PubMed was searched for studies with a similar design and a forward citation tracking was conducted using Google Scholar in June 2018. Results from a new sample and from published studies were combined in a random effect meta-analysis.

SETTING AND PARTICIPANTS

Family members of older adults with MCI or dementia.

MEASURES

The 5 major dimensions (neuroticism, extraversion, openness, agreeableness, and conscientiousness) and facets of personality were assessed with NEO Personality Inventory questionnaires.

RESULTS

The new sample (n = 50) and meta-analysis (18 samples; n = 542) found consistent shifts in personality from the premorbid to current state in patients with cognitive impairment. The largest changes (>1 standard deviation) were declines in conscientiousness (particularly for the facets of self-discipline and competence) and extraversion (decreased energy and assertiveness), as well as increases in neuroticism (increased vulnerability to stress). The new sample suggested that personality changes were larger in individuals taking cognition-enhancing medications (cholinesterase inhibitors or memantine). More recent studies and those that examined individuals with MCI found smaller effects.

CONCLUSIONS AND IMPLICATIONS

Consistent with the clinical criteria for the diagnosis of dementia, the new study and meta-analysis found replicable evidence for large changes in personality among individuals with dementia. Future research should examine whether there are different patterns of personality changes across etiologies of dementia to inform differential diagnosis and treatments. Prospective, repeated assessments of personality using both self- and informant-reports are essential to clarify the temporal evolution of personality change across the preclinical, prodromal, and clinical phases of dementia.

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.

[Premorbid personality as a risk factor in the appearance of psychological and behavioural symptoms of dementia: Systematic review]

The aetiology of behavioural and psychological symptoms of dementia (BPSD) is defined by a diversity of factors, and recent studies suggest that premorbid personality could be a risk factor for BPSD. This study aimed to review studies on the relationship between premorbid personality and BPSD. Studies were identified using PsycInfo, MedLine, and PubMed. The searches combined terms for premorbid personality, dementia and BPSD. Ten studies have been included in this review. Eight out of ten studies show a relationship between premorbid personality and BPSD. Neuroticism is associated with behavioural disturbances and anxiety. Extraversion is associated with wandering. Low agreeableness is associated with affective disturbance and aggression-related behaviours and high agreeableness is associated with wandering. The studies found no congruent results for openness and conscientiousness. In conclusion, premorbid personality may increase the risk of developing BPSD during the course of the disease. Even so, the relationship between personality and BPSD is complex due to multifactorial aetiology.

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 Across the Life Span

Trait stability and maturation are fundamental principles of contemporary personality psychology and have been shown to hold across many cultures. However, it has proven difficult to move beyond these general findings to a detailed account of trait development. There are pervasive and unexplained inconsistencies across studies that may be due to ( a) insufficient attention to measurement error, ( b) subtle but age-sensitive differences in alternative measures of the same trait, or ( c) different perspectives reflected in self-reports and observer ratings. Multiscale, multimethod-and ideally multinational-studies are needed. Several hypotheses have been proposed to account for trait stability and change, but supporting evidence is currently weak or indirect; trait development is a fertile if sometimes frustrating field for theory and research. Beyond traits, there are approaches to personality development that are of interest to students of adult development, and these may be fruitfully addressed from a trait perspective.

Chronic ghrelin administration restores hippocampal long-term potentiation and ameliorates memory impairment in rat model of Alzheimer's disease

Alzheimer's disease (AD), as a common age-related dementia, is a progressive manifestation of cognitive decline following synaptic failure resulted majorly by senile plaques composed of deposits of amyloid beta (Aβ). Ghrelin is a multifunctional peptide hormone with receptors present in various brain tissues including hippocampus and has been associated with neuroprotection, neuromodulation, and memory processing. Here, we investigated the neuroprotective and therapeutic effects of intracerebroventricular (icv) ghrelin infusion for 2 weeks on passive avoidance learning (PAL), memory retention, and synaptic plasticity in the hippocampal dentate gyrus (DG) and CA1 of both normal rats and Aβ1-42-induced neurotoxicity in AD model. Male Wistar rats were evaluated for their passive memory performance using a shuttle box while some groups had already received Aβ1-42 and/or chronic ghrelin. Using field potential recording, the induction of short- and long-term potentiation (STP and LTP) was studied in DG granule cells along with the LTP changes in CA1 pyramidal neurons through stimulation of the medial perforant path (mPP) and Schaffer collaterals (SCs), respectively. Our results demonstrated that chronic ghrelin treatment not only improved memory processing and retrieval in normal rats during the PAL task, but also promoted memory retention and alleviated memory loss by amelioration of Aβ1-42-induced synaptic plasticity impairment in AD subjects through augmentation of field excitatory postsynaptic potential (fEPSP) slope that led to LTP restitution in both the mPP-DG and the CA3-CA1 synapses. Meanwhile, STP was not significantly changed, meaning that although ghrelin enhanced postsynaptic excitability in DG, it did not change presynaptic transmitter release significantly. This suggests the involvement of postsynaptic mechanisms in long-term ghrelin-enhanced memory. In conclusion, it can be inferred that chronic ghrelin administration has an auspicious therapeutic value for impaired cognitive performance and memory deficits in AD-like neuropathology.

A Five-Factor Theory Perspective on Causal Analysis

Five-Factor Theory (FFT) provides a broad but largely blank template for causal personality research. Within FFT, there are three major categories of questions: (1) How do biological structures and functions lead to trait levels? (2) how do traits and the environment give rise to acquired psychological institutions? and (3) how do personality characteristics interact with specific situations to determine behaviors and reactions? Both practical and ethical issues complicate the search for the causes of trait change. Causal explanations of the development of characteristic adaptations are likely to be incomplete, because there are many different ways in which the same adaptation may be acquired. Studies of the determinants of behavior are usually left to social, educational, or clinical psychologists-although personality psychologists may make distinctive contributions by emphasizing the role of the individual in selecting and creating situations. A causal understanding of the functioning of the personality system is possible through the integration of many lines of evidence, but it is likely to take a very long time. In the meanwhile, personality psychologists may fruitfully pursue the identification of practical causes by which individuals with a given set of traits can optimize their adaptation. If we require truth in any strict sense, we must confine ourselves to one entire state of the world. This will be the cause, and the next entire state will be the effect. There is much truth in this conclusion, but it remains indefensible.F. H. Bradley, 1893/1966, p. 48.

Sphingolipid Metabolism: A New Therapeutic Opportunity for Brain Degenerative Disorders

Neurodegenerative diseases represent a class of fatal brain disorders for which the number of effective therapeutic options remains limited with only symptomatic treatment accessible. Multiple studies show that defects in sphingolipid pathways are shared among different brain disorders including neurodegenerative diseases and may contribute to their complex pathogenesis. In this mini review, we discuss the hypothesis that modulation of sphingolipid metabolism and their related signaling pathways may represent a potential therapeutic approach for those devastating conditions. The plausible “druggability” of sphingolipid pathways is greatly promising and represent a relevant feature that brings real advantage to the development of new therapeutic options for these conditions. Indeed, several molecules that selectively target sphingolipds are already available and many of them currently in clinical trial for human diseases. A deeper understanding of the “sphingolipid scenario” in neurodegenerative disorders would certainly enhance therapeutic perspectives for these conditions, by taking advantage from the already available molecules and by promoting the development of new ones.

Cognitive Impairment, Dementia, and Personality Stability Among Older Adults

There is contrasting evidence on personality stability in advanced age, and limited knowledge on the impact of cognitive impairment and dementia on trait stability. Group- and individual-level longitudinal analyses of the five major dimensions of personality assessed twice over 4 years ( N = 9,935) suggest that rank-order stability was progressively lower with advancing age (from rtt = 0.68 for age 50 to 60 years to rtt = 0.58 for age >80 years). Stability was low in the dementia group ( rtt = 0.43), and this was not simply due to lower reliability given that internal consistency remained adequate in the dementia group. Among individuals with no cognitive impairment or dementia, there was no association between stability and age ( rtt = 0.70 even for age >80 years). These results suggest that the lower personality stability in older adults is not due to age but cognitive impairment and dementia.

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.

Longitudinal personality change associated with cognitive decline in multiple sclerosis

We previously reported that personality and cognition were stable over 3 years in patients with multiple sclerosis (MS). This study examined whether a longer duration would reveal evidence of emerging personality dysfunction. The NEO Five-Factor Inventory and Brief International Cognitive Assessment for MS was used to assess personality and cognition, respectively. Patients were classified as "Cog Stable" or "Cog Decline" based on cognitive deterioration over 5 years. Extraversion and Conscientiousness declined across pooled groups. Follow-up of a group by time interaction found that decline in these traits was more evident in the Cog Decline group, demonstrating a link between personality and cognitive change.

Personality Change in the Preclinical Phase of Alzheimer Disease

IMPORTANCE

Changes in behavior and personality are 1 criterion for the diagnosis of dementia. It is unclear, however, whether such changes begin before the clinical onset of the disease.

OBJECTIVE

To determine whether increases in neuroticism, declines in conscientiousness, and changes in other personality traits occur before the onset of mild cognitive impairment or dementia.

DESIGN, SETTING, AND PARTICIPANTS

A cohort of 2046 community-dwelling older adults who volunteered to participate in the Baltimore Longitudinal Study of Aging were included. The study examined personality and clinical assessments obtained between 1980 and July 13, 2016, from participants with no cognitive impairment at first assessment who were followed up for as long as 36 years (mean [SD], 12.05 [9.54] years). The self-report personality scales were not considered during consensus diagnostic conferences.

MAIN OUTCOMES AND MEASURES

Change in self-rated personality traits assessed in the preclinical phase of Alzheimer disease and other dementias with the Revised NEO Personality Inventory, a 240-item questionnaire that assesses 30 facets, 6 for each of the 5 major dimensions: neuroticism, extraversion, openness, agreeableness, and conscientiousness.

RESULTS

Of the 2046 participants, 931 [45.5%] were women; mean (SD) age at first assessment was 62.56 (14.63) years. During 24 569 person-years, mild cognitive impairment was diagnosed in 104 (5.1%) individuals, and all-cause dementia was diagnosed in 255 (12.5%) participants, including 194 (9.5%) with Alzheimer disease. Multilevel modeling that accounted for age, sex, race, and educational level found significant differences on the intercept of several traits: individuals who developed dementia scored higher on neuroticism (β = 2.83; 95% CI, 1.44 to 4.22; P < .001) and lower on conscientiousness (β = -3.34; 95% CI, -4.93 to -1.75; P < .001) and extraversion (β = -1.74; 95% CI, -3.23 to -0.25; P = .02). Change in personality (ie, slope), however, was not significantly different between the nonimpaired and the Alzheimer disease groups (eg, neuroticism: β = 0.00; 95% CI, -0.08 to 0.08; P = .91; conscientiousness: β = -0.06; 95% CI, -0.16 to 0.04; P = .24). Slopes for individuals who developed mild cognitive impairment (eg, neuroticism: β = 0.00; 95% CI, -0.12 to 0.12; P = .98; conscientiousness: β = -0.09; 95% CI, -0.23 to 0.05; P = .18) and all-cause dementia (eg, neuroticism: β = 0.02; 95% CI, -0.06 to 0.10; P = .49; conscientiousness: β = -0.08; 95% CI, -0.16 to 0.00; P = .07) were also similar to those for nonimpaired participants.

CONCLUSIONS AND RELEVANCE

No evidence for preclinical change in personality before the onset of mild cognitive impairment or dementia was identified. These findings provide evidence against the reverse causality hypothesis and strengthen evidence for personality traits as a risk factor for dementia.