Trajectories of Personality Traits Preceding Dementia Diagnosis

Disease trajectory of high neuroticism and the relevance to psychiatric disorders: A retro-prospective cohort study

BACKGROUND

Neuroticism is a psychological personality trait that has a significant impact on public health and is also a potential predisposing factor for adverse disease outcomes; however, comprehensive studies of the subsequently developed conditions are lacking. The starting point of disease trajectory in terms of genetic variation remains unclear.

METHOD

Our study included 344,609 adult participants from the UK Biobank cohort who were virtually followed up from January 1, 1997. Neuroticism levels were assessed using 12 items from the Eysenck Personality Questionnaire. We performed a phenome-wide association analysis of neuroticism and subsequent diseases. Binomial tests and logistic regression models were used to test the temporal directionality and association between disease pairs to construct disease trajectories. We also investigated the association between polygenic risk scores (PRSs) for five psychiatric traits and high neuroticism.

RESULTS

The risk for 59 diseases was significantly associated with high neuroticism. Depression, anxiety, irritable bowel syndrome, migraine, spondylosis, and sleep disorders were the most likely to develop, with hazard ratios of 6.13, 3.66, 2.28, 1.74, 1.74, and 1.71, respectively. The disease trajectory network revealed two major disease clusters: cardiometabolic and chronic inflammatory diseases. Medium/high genetic risk groups stratified by the PRSs of four psychiatric traits were associated with an elevated risk of high neuroticism. We further identified eight complete phenotypic trajectory clusters of medium or high genetic risk for psychotic, anxiety-, depression-, and stress-related disorders.

CONCLUSION

Neuroticism plays an important role in the development of somatic and mental disorders. The full picture of disease trajectories from the genetic risk of psychiatric traits and neuroticism in early life to a series of diseases later provides evidence for future research to explore the etiological mechanisms and precision management.

Are trajectories of personality and socioeconomic factors prospectively associated with midlife cognitive function? Findings from a 12-year longitudinal study of Mexican-origin adults

Problems with memory, executive function, and language are a significant public health concern, especially when they begin during midlife. However, there is relatively little work on risk and protective factors for cognitive function in middle adulthood. Using data from 883 Mexican-origin adults assessed up to 6 times across 12 years (Mage at Time 1 = 38.2 years; range = 27-63 years), the present study examined whether developmental trajectories (levels and slopes) of Big Five personality domains and socioeconomic factors (per capita income, economic stress) were prospectively associated with cognitive function (memory, mental status, verbal fluency) at the final assessment. We found that individuals with higher levels of, and smaller decreases in, Neuroticism had worse cognitive function 12 years later. Further, individuals with higher initial Conscientiousness had better subsequent memory, mental status, and verbal fluency, and individuals with higher Openness and Extraversion had better subsequent verbal fluency (but not memory or mental status). The trajectories of per capita income and economic stress were robustly associated with cognitive function, such that higher initial levels and greater increases in socioeconomic resources had protective associations, whereas higher levels and greater increases in economic stress had deleterious associations with cognitive function. Higher education level was associated with better cognitive function 12 years later. These findings suggest that changes in personality and socioeconomic factors across adulthood are associated with cognitive function, which may be informative for interventions to support healthier cognitive aging starting at least as early as midlife. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

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.

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.

Physical activity is associated with lower cerebral beta-amyloid and cognitive function benefits from lifetime experience-a study in exceptional aging

BACKGROUND

Exceptional agers (85+ years) are characterized by preserved cognition presumably due to high cognitive reserve. In the current study, we examined whether personality, risk and protective factors for dementia as well as quality of life are associated with core features of Alzheimer's disease (amyloid-deposition and hippocampal volume) as well as cognition in exceptional aging.

METHODS

We studied 49 exceptional agers (average 87.8 years, range 84-94 years), with preserved activities of daily living and absence of dementia. All participants received a detailed clinical and neuropsychological examination. We used established questionnaires to measure lifetime experience, personality, recent physical and cognitive activity as well as quality of life. Cerebral amyloid-deposition was estimated by 18-[F]-Flutemetamol-PET and manual hippocampal volumetry was performed on 3D T1 MRI images.

RESULTS

In this sample of exceptional agers with preserved activities of daily living, we found intact cognitive performance in the subjects with the highest amyloid-load in the brain, but a lower quality of life with respect to autonomy as well as higher neuroticism. Higher self-reported physical activity in the last twelve months went with a lower amyloid load. Higher self-reported leisure-time/ not work-related activity went with better executive functioning at older age.

CONCLUSION

Even in exceptional aging, high amyloid load may subtly influence personality and quality of life. Our findings support a close relationship between high physical activity and low amyloid-deposition and underscore the importance of extracurricular activities for executive functions. As executive functions are known to be a central resource for everyday functioning in fostering extracurricular activities may be effective in delaying the onset of dementia.

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.

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.

Increases in Neuroticism May Be an Early Indicator of Dementia: A Coordinated Analysis

OBJECTIVES

Although personality change is typically considered a symptom of dementia, some studies suggest that personality change may be an early indication of dementia. One prospective study found increases in neuroticism preceding dementia diagnosis (Yoneda, T., Rush, J., Berg, A. I., Johansson, B., & Piccinin, A. M. (2017). Trajectories of personality traits preceding dementia diagnosis. The Journals of Gerontology. Series B, Psychological Sciences and Social Sciences, 72, 922-931. doi:10.1093/geronb/gbw006). This study extends this research by examining trajectories of personality traits in additional longitudinal studies of aging.

METHODS

Three independent series of latent growth curve models were fitted to data from the Longitudinal Aging Study Amsterdam and Einstein Aging Study to estimate trajectories of personality traits in individuals with incident dementia diagnosis (total N = 210), in individuals with incident Mild Cognitive Impairment (N = 135), and in individuals who did not receive a diagnosis during follow-up periods (total N = 1740).

RESULTS

Controlling for sex, age, education, depressive symptoms, and the interaction between age and education, growth curve analyses consistently revealed significant linear increases in neuroticism preceding dementia diagnosis in both datasets and in individuals with mild cognitive impairment. Analyses examining individuals without a diagnosis revealed nonsignificant change in neuroticism overtime.

DISCUSSION

Replication of our previous work in 2 additional datasets provides compelling evidence that increases in neuroticism may be early indication of dementia, which can facilitate development of screening assessments.

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).

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.