Hindawi Behavioural Neurology Volume 2020, Article ID 5232184, 6 pages https://doi.org/10.1155/2020/5232184 Research Article Personality Factors and Subjective Cognitive Decline: The FACEHBI Cohort Nathalia Muñoz,1 Montserrat Gomà-i-Freixanet,2 Sergi Valero ,1,3 Octavio Rodríguez-Gómez,1,3 Angela Sanabria,1,3 Alba Pérez-Cordón,1 Isabel Hernández,1,3 Marta Marquié,1,3 Iolao Mir,2 Elvira Martín,1 Alba Benaque,1 Agustín Ruiz,1,3 Lluís Tarraga,1,3 Mercè Boada,1,3 Montserrat Alegret ,1,3 and on behalf of the FACEHBI study1 1 Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya, Barcelona, Spain 2 Department of Clinical and Health Psychology, Universitat Autònoma de Barcelona, 08193 Barcelona, Catalonia, Spain 3 Networking Research Center on Neurodegenerative Diseases (CIBERNED), Instituto de Salud Carlos III, 28029 Madrid, Spain Correspondence should be addressed to Sergi Valero; svalero@fundacioace.org Received 4 June 2019; Revised 28 October 2019; Accepted 2 December 2019; Published 19 February 2020 Academic Editor: Enzo Emanuele Copyright © 2020 Nathalia Muñoz et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Individuals with subjective cognitive decline (SCD) have the perception of memory problems without showing impairment on standardized cognitive tests. SCD has been associated with an increased risk of developing Alzheimer’s disease (AD). Neuroticism and openness personality dimensions have also been associated with SCD and AD. From the aforementioned, we aimed to ascertain whether the dimensions and traits defined by the Zuckerman-Kuhlman Personality Questionnaire (ZKPQ) differentiate between individuals with SCD and the general population (GP). A total of 187 participants with SCD and mild affective symptomatology recruited from the Fundació ACE Health Brain Initiative (FACEHBI) project completed the ZKPQ. Each SCD participant was matched by sex and age to an individual from the GP. Both samples included 71 men and 116 women with a mean age of 65.9 years. Results indicated that the SCD group scored significantly lower in Neuroticism-Anxiety and Activity than the GP group. Only Activity remained statistically significant in a multivariate analysis. These findings suggest that individuals with SCD have a low energy level and a dislike for an active and busy life. From the obtained results and knowing additional physical activities may delay the conversion from normal aging to cognitive impairment, we encourage promoting this lifestyle in daily routine. The assessment of personality may result in an SCD plus feature, which may serve as an upgrading strategy for future research. 1. Introduction only genetic and environmental factors but also individual differences in personality [3, 5, 7] that could influence Subjective cognitive decline (SCD) refers to the perception of the vulnerability of cognitive decline [9]. Increasing the suffering from memory or other cognitive problems without knowledge of these factors might enhance the detection objective impairment on standardized cognitive tests [1, 2]. of early signs of cognitive decline and further research Longitudinal studies have shown that elderly individuals especially in cases with Mild Cognitive Impairment (MCI) referring SCD have an increased risk of progression to or AD development. cognitive impairment and display functional deficits and Specific personality factors could be an early sign of higher prevalence of postmortem Alzheimer’s disease (AD) cognitive decline. A meta-analysis with 5,054 cognitively pathology compared to those who do not perceive cognitive healthy individuals showed that those with scores in the top problems [3–8]. Determinants of SCD in aging include not quartile of neuroticism or in the lowest quartile of 2 Behavioural Neurology conscientiousness had a threefold increased risk of develop- Clinical Dementia Rating (CDR) Scale [26], (e) a perfor- ing AD [10]. Moreover, a recent study has also reported an mance within the average range expected for age and educa- association between SCD and brain amyloid-β burden spe- tional level on the Fundació ACE Neuropsychological cifically among individuals with high, but not low, neuroti- Battery (NBACE) [27, 28], (f) were literate, and (g) had com- cism [11]. Cross-sectional studies have also found SCD to pleted the self-administered questionnaire ZKPQ. be associated with AD biomarkers [1, 12–14] and with The exclusion criteria for the SCD group were (a) having affective symptomatology, such as depression and anxiety a score of ≥11 in either of the two scales of the HADS [22], [12, 15]. Consequently, the cooccurrence of preclinical AD (b) having a history of alcoholism, epilepsy, or current signs and affective symptomatology may affect the scores serious medical or psychiatric illness, (c) displaying auditory obtained from personality questionnaires, but we do not or visual impairments interfering with neuropsychological know yet how they interact. Thus, studies on personality assessment, and (d) evidencing functional impairment due and SCD ought to control for depressive and anxiety symp- to cognitive decline, with a score higher than 3 on the Blessed toms [1, 15]. Nonetheless, most of the previously mentioned Dementia Rating Scale (BDRS) [29, 30]. Further description studies have only excluded participants with severe psychiat- of inclusion and exclusion criteria is provided in ric symptomatology, i.e., displaying active major depression Rodríguez-Gómez et al. [20]. or been hospitalized for depression within the last year Participants constituting the GP sample were extracted [11, 16, 17], but not those with affective symptomatology. from a broader study of a total of 1,678 participants [23]. The objective of our study has been addressed to As this population was intended to obtain the Spanish determine whether the major dimensions/traits of person- norms, no inclusion/exclusion criteria were applied. ality as defined by the alternative five factor (AFF) [18] The final total sample consisted of 187 participants model––Neuroticism-Anxiety, Activity, Sociability, Impul- (71 men, 116 women) meeting criteria for SCD and 187 sive Sensation-Seeking, and Aggression-Hostility––would participants from the GP sample, matched by sex and age. differentiate individuals with SCD from those of the The mean age of the total sample was 65.89 (SD = 7:29). general population (GP) using the Zuckerman-Kuhlman With regard to the level of education of the SCD and GP Personality Questionnaire (ZKPQ) [19]. samples, 21.9% and 40.1% completed elementary school, The SCD sample was drawn from a cohort of participants 27.8% and 20.9% high school, and 50.3% and 39% a bache- [20] from the Fundació ACE Healthy Brain Initiative lor’s degree, respectively. In the present study, we did not (FACEHBI), a longitudinal study comprising the assessment exclude any participant due to the scores on the Infrequency of biomarkers, risk factors, lifestyle, and cognition in individ- scale and all were Caucasian. uals with SCD aged older than 49 years. This cohort has shown APOE ε4 (apolipoprotein with polymorphic alleles 2.2. Measures are the main genetic determinants of AD) enrichment, sug- gesting that a pool of potential AD patients could probably 2.2.1. Psychological Assessments. Personality was assessed by be nested in this sample [21]. the ZKPQ [23], a questionnaire designed to measure normal To ensure that memory complaints were not due to personality and not psychological abnormalities. The ZKPQ affective symptomatology but to subjective perception of consists of 99 items in a “true-false” answering format. This cognitive decline, participants scoring over the Spanish cut- questionnaire evaluates five major personality factors and off on the Hospital Anxiety and Depression Scale (HADS) includes an Infrequency scale that allows eliminating subjects [22] were not included in the study. The GP sample was part with careless responding. This scale ensures that none of the of a broader study designed to obtain the Spanish norms of responses is affected by set bias and it controls inaccurate the ZKPQ [23]. The present study deepens the knowledge responding. This Infrequency scale (10 items) detects inat- on the characteristics of individuals with SCD and explores tention to the task and can be used as a validity measure for the relationship between personality and SCD. the individual test taker. The items in this scale are mostly exaggerated, true scored, socially desirable, but unlikely to 2. Materials and Methods be completely true statements about anyone. This scale is highly skewed, with most scores around 0 or 1. 2.1. Participants. Participants with SCD were recruited from The five scales can be described as follows: (1) the FACEHBI project [20], which consisted of 200 individ- Neuroticism-Anxiety (N-Anx, 19 items) items describe fre- uals. For the purpose of the present study, only those having quent emotional upset, tension, worry, fearfulness, indecision, completed the ZKPQ were included in the SCD group lack of self-confidence, and sensitivity to criticism. (2) Activity (n = 187). Comparing those who have responded the ZKPQ (Act, 17 items) items describe the need for general activity, an with those who have not responded it, both groups did not inability to relax and do nothing when the opportunity arises, differ on the Mini-Mental State Examination (MMSE) [24] and a preference for hard and challenging work, an active, busy (Mann–Whitney U test, p = :241), age (Mann–Whitney U life, and a high energy level. (3) Sociability (Sy, 17 items) items test, p = :655), and sex (Fisher exact test, p = :379). describe outgoingness at parties, the number of friends one has SCD was defined as (a) age older than 49 years, (b) a score and the amount of time spent with them, and a preference for of ≥8 on the Spanish modified questionnaire of Memory being with others as opposed to being alone and engaging in Failures of Everyday (MFE-30) [25], (c) a score of ≥27 on solitary activities. (4) Impulsive Sensation-Seeking (ImpSS, the Spanish version of the MMSE, (d) a score of 0 on the 19 items) items involve a lack of planning and the tendency Behavioural Neurology 3 to act impulsively without thinking and the seeking for Participants for the GP sample were contacted from very excitement, novel experiences, and the willingness to take different sites (classroom, home, while waiting for a yearly risks for these types of experiences. These items are expressed health check, leisure associations, etc.) and asked to answer in a general manner and do not describe specific activities the ZKPQ questionnaire. The questionnaire was provided such as drinking or sex. (5) Aggression-Hostility (Agg-Host, with written instructions and an introductory letter explain- 17 items) items describe a readiness to express verbal aggres- ing globally the goal of the study (“the study you will collab- sion; rude, thoughtless, or antisocial behavior; vengefulness orate in attempts to evaluate the functioning of an American and spitefulness; having a quick temper and impatience questionnaire in our culture”). Most of the questionnaires towards others. This test has shown good psychometric were administered in a group situation and others individu- properties in Spanish samples, with internal consistency ally. In this latter situation, the subject also received a prepaid alpha coefficients ranging from 0.70 to 0.85 [31] and high envelope, which had to be posted. consensual validity parameters [32]. The factorial structure Participation in the FACEHBI and the GP group was has also been replicated in Spanish samples with congruence both voluntary and without remuneration. Questionnaires coefficients to USA samples, ranging from 0.84 to 0.96 [23]. of the SCD group were signed and keep confidential. Ques- tionnaires of the GP group were obtained anonymously. 2.2.2. Blood Sampling, APOE Genotyping. As detailed else- where [21], in the SCD sample, blood samples after fasting 2.4. Statistical Analysis. To assess differences between SCD have been obtained in all the visits for standard biochemical and GP groups on the ZKPQ factors, we performed a two- analysis, determination of blood amyloid species, APOE tailed independent Student’s t-test and calculated Cohen’s d. genotyping, and DNA banking. In a second step, we executed a logistic regression analysis Genomic DNA was extracted from 200 μl of human and as predictors we introduced the personality variables that whole blood using Maxwell® 16 Blood DNA purification kit previously obtained a significant effect in the bivariate analy- (Promega) according to the manufacturer’s instructions. sis. Educational level was incorporated in the model (as APOE rs7412 and rs42358 markers were genotyped using dummy variable) because it was heterogeneously distributed real-time PCR. PCR reactions were performed in a final in both groups. As both samples were matched by age and volume of 5 μl, using 11 ng of genomic DNA, 0.3 μM of each sex, these two variables were not considered as covariates. amplification primer, and 2.65 μl of 2X SYBR Fast Master A conditional entrance strategy was applied to select the final Mix (Kapa Biosystems). We used an initial denaturation step significant personality model. The dichotomous status of at 95°C for 2 min, followed by 33 cycles at 95°C for 10 s, and at participants (coded as 1 = SCD, 0 = GP) was the dependent 69°C for 30 s. Melting curves were 95°C for 15 s (ramping rate factor. We used the SPSS v20, and the alpha risk assumed 5.5°Cs), 45°C for 15 s (ramping rate of 5.5°Cs−1), and 95°C was 5%. for 15 s (ramping rate of 5.5°Cs−1). In the last step of each melting curve, a continuous fluorimetric register was per- 3. Results formed by the system at one acquisition register per each degree Celsius. Melting peaks and genotype calls were Table 1 shows means, standard deviations, and alphas for the obtained using the Eco Real-Time PCR system (Illumina). SCD and GP groups. Group comparisons showed differences between groups on the Neuroticism-Anxiety and Activity 2.3. Procedure. Data from participants with SCD were scales, with the SCD group scoring significantly lower on obtained from the FACEHBI project. Participants were both scales. referred by their general health practitioner to Fundació Table 2 shows correlations between ZKPQ scales for both ACE in order to be assessed for possible cognitive impair- groups. While several statistically significant correlations ment, or approached Fundació ACE through an Open House were found in the GP group, in the SCD group, only Agg- Initiative in which any citizen can sign up for free cognitive Host with N-Anx and ImpSS showed a statistically signifi- screening without the need of medical referral. This initiative cant and positive association (.38 and .14, respectively). encompasses a community service and a recruitment strategy With regard to the SCD group, comparing APOE ε4 car- for research studies. A neuropsychologist administered the riers with noncarriers, results indicated that they did not dif- NBACE, HADS, MFE-30, and the ZKPQ, and a neurologist fer in any of the ZKPQ personality variables (for all administered the MMSE and the neurological exploration. comparisons p > :23). A nurse performed blood extraction for amyloid. Both proce- To determine the specific contribution of Neuroticism- dures were performed at Fundació ACE. The SCD partici- Anxiety and Activity scales to discriminate between SCD pants gave written consent and research protocol was and GP groups, we conducted a logistic regression analysis. approved by the ethics committee of the Hospital Clinic i Since both groups differed in educational level (χ2 = 14:62, Provincial (Barcelona, Spain) (EudraCT: 2014-000798-38). p = :001), we included this variable in the multivariate analy- Data from the GP sample were obtained from a broader sis as an adjustment factor. The educational level was classi- study designed to obtain the Spanish norms of the ZKPQ fied into three categories; hence, we created two dummy [23]. This sample consisted of a total 1,678 participants, variables that were introduced into the model. The Activity 741 males (44.2%) and 937 females (55.8%). From the GP scale was the only variable that remained statistically signifi- sample, 187 participants were randomly extracted and cant in the final model (Wald = 5:50, p = :019, OR = 1:08, matched by sex and age to participants of FACEHBI study. 95%CI = 1:01‐1:15). 4 Behavioural Neurology Table 1: Comparison of the ZKPQ scale scores between the SCD and control groups, Cronbach’s alphas, and effect sizes. SCD group (n = 187) GP group (n = 187) ZKPQ scale α α t p Cohen’s d Mean SD Mean SD N-Anx 7.05 4.40 .84 8.06 4.68 .83 2.41 .033∗ .22 Act 7.67 3.50 .74 8.56 3.25 .76 2.55 .011∗ .26 Sy 6.68 3.57 .76 6.84 3.29 .76 .45 .652 .05 ImpSS 6.46 4.09 .82 6.97 3.70 .87 1.25 .214 .13 Agg-Host 6.20 3.20 .74 6.30 3.13 .77 .33 .744 .03 Inf 2.85 2.20 — 3.09 1.95 — 1.09 .275 .11 Note: SCD: subjective cognitive decline; GP: general population; N-Anx: Neuroticism-Anxiety; Act: Activity; Sy: Sociability; ImpSS: Impulsivity Sensation- Seeking; Agg-Host: Aggression-Hostility; Inf: Infrequency. ∗ p < :05. Table 2: Correlations between ZKPQ scales by group. Consequently, the cross-sectional design of our study is a limitation and further longitudinal studies are needed to ZKPQ N-Anx Act Sy ImpSS Agg-Host determine whether individuals with SCD and scoring low N-Anx -.02 -.02 .07 .38∗∗ on the activity personality trait may have an increased risk Act .09 .08 -.06 .06 for developing future cognitive decline and AD. However, the strengths of the present study must also be Sy -.06 .13 -.05 .05 mentioned. First, all participants underwent an extensive ImpSS .19∗∗ .32∗∗ .25∗∗ .14∗ neuropsychological protocol to ensure that they had a Agg-Host .28∗∗ .24∗∗ .06 .29∗∗ neuropsychological preserved performance, and subjective Note: up-diagonal correlations in the FACEHBI group. Below-diagonal cognitive complaints assessed through a standardized ques- correlations in the GP group. N-Anx: Neuroticism-Anxiety; Act: tionnaire. Second, each participant from the SCD group Activity; Sy: Sociability; ImpSS: Impulsivity Sensation-Seeking; Agg-Host: was matched by age and sex to a participant from the GP. Aggression-Hostility. ∗ p < :05; ∗∗ p < :005. Third, the major dimensions of personality were assessed within the alternative five factor model in which the scale 4. Discussion level analyses of the ZKPQ [19, 36] allowed to examine which specific trait of the personality dimensions was most strongly The SCD has been established as a risk factor for develop- related to AD. ing AD and it has been identified as a potential early stage Studies on lifestyle risk factors for developing AD have of the disease [1]. To our knowledge, this is the first study shown that decreased general activity is an important risk that has analyzed the relationship between SCD and per- factor as they are low educational level, diabetes, smoking, sonality assessed by the ZKPQ by comparing individuals midlife obesity, hypertension, and depression [10]. Further- referring SCD with a general population sample matched more, the recent WHO guidelines for prevention of dementia by sex and age. states that physical activity should be recommended to adults The results of the present study revealed that participants with normal cognition in order to reduce the risk of cognitive with SCD scored lower on the Neuroticism-Anxiety and decline. It is important to take into account the potential risk Activity scales than the GP sample. Furthermore, when we factors, which would help in the prevention of dementia, as determined the specific contribution of these two scales in well as interventions that delay the cognitive decline [37]. discriminating between both groups, only the Activity scale The results of the present study suggest that personality remained in the model, indicating that individuals with traits might help to characterize individuals with SCD; hence, SCD refer a low energy level and a dislike for an active and including the assessment of personality in SCD protocols busy life. would be welcomed. Studies provide support for that physi- Our results indicate that those participants referring cal activity [38] and cognitive activities [39] offer some SCD have lower levels of general activity, including doing reduction in AD. Clinicians would prescribe modifying ther- things when the opportunity arises, a dislike for hard and apies, such as personalized physical exercise [40] or cognitive challenging work, for an active and busy life, and display a stimulation, to delay the onset of cognitive impairment or low energy level. A longitudinal study would help to dis- dementia. Early care programs might introduce actions to entangle the question whether this low physical activity encourage people to increase their cognitive and physical is due to personality characteristics per se or, in contrast, activities. it is an incipient preclinical sign of AD [33], as lower activity can be consistent with changes intrinsic to the dis- 5. Conclusions ease process itself [34]. Overall, it becomes difficult to determine which complaints underlie AD, because there The present study showed that compared to the general pop- is a close relationship between SCD complaints and other ulation, Activity trait is lower in individuals with SCD, indi- variables such as personality traits [35]. cating lower preference for an active and busy life, and lower Behavioural Neurology 5 energy level. Personality test may be helpful in characterizing [3] M. I. Geerlings, C. Jonker, L. M. Bouter, H. J. Ader, and persons with SCD. The assessment of personality may result B. Schmand, “Association between memory complaints and in an SCD plus feature, which may serve as an upgrading incident Alzheimer’s disease in elderly people with normal strategy for future research. baseline cognition,” American Journal of Psychiatry, vol. 156, no. 4, pp. 531–537, 1999. [4] C. Jonker, L. J. Launer, C. Hooijer, and J. 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