Measuring executive dysfunction in Parkinson's disease: Reliability and validity of the Spanish version of Frontal Assessment Battery (FAB-E)

The assessment of executive functions to test the integrity of the nigrostriatal network: A pilot study

Background

Parkinson’s disease (PD) is a chronic neurodegenerative disorder characterized by motor and non-motor symptoms. The latter mainly include affective, sleep, and cognitive deficits. Non-demented PD patients often demonstrate impairments in several executive domains following neuropsychological evaluation. The current pilot study aims at assessing the discriminatory power of the Frontal Assessment Battery-15 (FAB15) in differentiating (i) non-demented PD patients and healthy controls and (ii) PD patients with more and less pronounced motor symptoms.

Methods

Thirty-nine non-demented early-stage PD patients in the “on” dopamine state (26 females, mean age = 64.51 years, SD = 6.47, mean disease duration = 5.49 years, SD = 2.28) and 39 healthy participants (24 females, mean age = 62.60 years, SD = 5.51) were included in the study. All participants completed the FAB15. Motor symptoms of PD patients were quantified via the Unified Parkinson’s Disease Rating Scale-Part III (UPDRS-Part III) and Hoehn and Yahr staging scale (H&Y).

Results

The FAB15 score, adjusted according to normative data for sex, age, and education, proved to be sufficiently able to discriminate PD patients from healthy controls (AUC = 0.69 [95% CI 0.60–0.75], SE = 0.06, p = 0.04, optimal cutoff = 11.29). Conversely, the battery lacked sufficient discriminative capability to differentiate PD patients based on the severity of motor symptoms.

Conclusion

The FAB15 may be a valid tool for distinguishing PD patients from healthy controls. However, it might be less sensitive in identifying clinical phenotypes characterized by visuospatial impairments resulting from posteroparietal and/or temporal dysfunctions. In line with previous evidence, the battery demonstrated to be not expendable in the clinical practice for monitoring the severity of PD-related motor symptoms.

Coenzyme Q10 Levels Associated With Cognitive Functioning and Executive Function in Older Adults

Brain deterioration with age is associated with inflammation and oxidative stress that result in structural and functional changes. Recent studies have indicated that coenzyme Q10 (CoQ10) is associated with neurological oxidative stress and cognitive impairment. Studies with older people have shown a relationship between neurodegenerative diseases and CoQ10 levels. However, no studies have analyzed the relationship between CoQ10 and cognitive functioning in older adults. The aim of this study was to analyze the association between CoQ10 and cognitive functioning in an older adult sample, controlling for other factors that may influence aging, such as the level of physical activity and nutritional status. The sample consisted of 64 older adults aged 65-99 years (76.67 ± 8.16 years), among whom 48 were women (75%). The participants were recruited among those who attended community centers to voluntarily participate in leisure activities. According to previous studies, physical activity and nutritional status are positively associated with cognitive functioning. However, the main finding of this study was that plasma CoQ10, controlling for other measures, was significantly associated with cognitive functioning and executive function. The current findings suggest that a decline in cognitive capacities may be related to reduced antioxidant defenses, as reflected by low CoQ10 levels in older adults.

Psychometric properties of the Spanish version of the Frontal Assessment Battery (FAB-E) and normative values in a representative adult population sample

BACKGROUND

The Frontal Assessment Battery is a short bedside test used to assess executive functions (EF). The aims of the present study were, first, to evaluate the psychometric proprieties of the Spanish version of the FAB (FAB-E) in a representative sample, and second, to establish cut-off points for impairment in executive function according to age and education level.

METHODS

A sample of 798 healthy Spanish adult subjects aged 19 to 91 participated in this study. Neuropsychological assessment of participants was conducted using the FAB-E, Mini-Mental State Examination (MMSE) and Trail Making Test (TMT). We examined internal consistency, intraclass correlation, test-retest reliability, and concurrent and divergent validity. In addition, we established a cut-off point for detecting executive function impairment based on the 5th percentile by age group and education level.

RESULTS

The analysis of the psychometric properties of the FAB-E showed good internal consistency (Cronbach's α = 0.60), intraclass correlation (0.72), test-retest reliability (0.70) and concurrent and divergent validity between the TMT (r = -0.523), MMSE (r = 0.426) and the FAB-E. The cut-off points for each age group were 16 points for the ≤ 29 group, 15 points for the 30-39 group, 14 points for the 40-49 and 50-59 groups, 12 points for the 60-69 group, and 10 points for the ≥ 70 age group.

CONCLUSIONS

The psychometric analysis showed that the FAB-E has good validity and reliability. Thus, FAB-E may be a helpful tool to evaluate EF in a healthy Spanish population. In addition, this study provides information on reference data that will be very valuable for clinicians and researchers.

Objectively measured secondhand tobacco smoke and cognitive impairment in disability-free older adults

Previous studies have suggested that exposure to secondhand smoke (SHS) may be associated with greater risk of cognitive impairment. However, no longitudinal study has examined the association of serum cotinine (as objective measure of SHS exposure) and cognitive function in older adults. We used data from 2087 non-smoking adults aged≥65 years participating in the ENRICA-2 cohort and free from limitations in Instrumental Activities of Daily Living. Cognitive function was assessed through the Mini-Mental State Examination (MMSE), the Digit Span Backwards subtest (DSBT), the Luria's motor series subtest from the Frontal Assessment Battery, the Trail Making Test A (TMT-A), the Free and Cued Selective Reminding Test (FCSRT), and the Categorical Verbal Fluency Test (CFT) of the 7 min test. Cross-sectional analyses were performed using multivariable logistic and ordered logistic models, while analyses on changes in cognition over time used multivariable repeated-measures mixed-effects models. Compared to the unexposed, those in the highest exposure group (≥0.161 ng/ml) were more likely to have cognitive impairment (MMSE<24) (odds ratio [OR]:1.64; 95% confidence interval [CI]:1.04-2.60) and lower DSBT scores (OR:1.25; 95%CI:1.00-1.57), as well as a non-significant higher odds of a lower score in the Luria test (OR:1.23; 95%CI:0.92-1.64) or episodic memory impairment (FCSRT<12, OR:1.38; 95%CI:0.90-2.11). In longitudinal analyses, those with baseline cotinine ≥0.161 ng/ml showed an increased risk of cognitive impairment (MMSE<24,OR:2.23; 95%CI:1.14-4.33; p-trend across cotinine categories = 0.028) and decreased DSBT (OR:1.23; 95%CI:1.01-1.51; p-trend across cotinine categories = 0.046). Findings show an increased risk of global cognitive impairment and declines in working memory performance in older adults exposed to SHS. More efforts are needed to protect older adults from SHS in areas not covered by smoke-free legislation.

Functional Relationship between Inhibitory Control, Cognitive Flexibility, Psychomotor Speed and Obesity

In the last decades, it has been proposed that executive functions may be particularly vulnerable to weight-related issues. However, evidence on the matter is mixed, especially when the effects of sociodemographic variables are weighted. Thus, the current study aimed at further examining the relationship between executive functions and obesity. To this aim, we compared treatment-seeking overweight, obese, and morbidly obese patients with normal-weight control participants. We examined general executive functioning (Frontal Assessment Battery−15) and different executive subdomains (e.g., inhibitory control, verbal fluency, and psychomotor speed) in a clinical sample including 208 outpatients with different degrees of BMI (52 overweight, BMI 25−30, M age = 34.38; 76 obese, BMI 30−40, M age = 38.00; 80 morbidly obese, BMI > 40, M age = 36.20). Ninety-six normal-weight subjects served as controls. No difference on executive scores was detected when obese patients were compared with over- or normal-weight subjects. Morbidly obese patients reported lower performance on executive scores than obese, overweight, and normal-weight subjects. Between-group difference emerged also when relevant covariates were taken into account. Our results support the view that morbid obesity is associated with lower executive performance, also considering the critical role exerted by sociodemographic (i.e., sex, age, and education) variables. Our results support the view that executive functioning should be accounted into the management of the obese patient because of non-negligible clinical relevance in diagnostic, therapeutic, and prognostic terms.

Executive Functions in Overweight and Obese Treatment-Seeking Patients: Cross-Sectional Data and Longitudinal Perspectives

BACKGROUND

Recent evidence suggests that a higher body weight may be linked to cognitive impairment in different domains involving executive/frontal functioning. However, challenging results are also available. Accordingly, our study was designed to verify whether (i) poor executive functions are related to a higher body weight and (ii) executive functioning could contribute to weight loss in treatment-seeking overweight and obese patients.

METHODS

We examined general executive functioning, inhibitory control, verbal fluency, and psychomotor speed in a sample including 104 overweight and obese patients. Forty-eight normal-weight subjects participated in the study as controls.

RESULTS

Univariate Analysis of Variance showed that obese patients obtained lower scores than overweight and normal-weight subjects in all executive measures, except for errors in the Stroop test. However, when sociodemographic variables entered the model as covariates, no between-group difference was detected. Furthermore, an adjusted multiple linear regression model highlighted no relationship between weight loss and executive scores at baseline.

CONCLUSIONS

Our results provide further evidence for the lack of association between obesity and the executive domains investigated. Conflicting findings from previous literature may likely be due to the unchecked confounding effects exerted by sociodemographic variables and inclusion/exclusion criteria.

The ATENción Plena en Enfermedad de Alzheimer (ATENEA—Mindfulness in Alzheimer’s Disease) Program for Caregivers: Study Protocol for a Randomized Controlled Trial

A person affected by Alzheimer’s disease (AD) gradually loses the ability to perform activities of daily living and becomes dependent on caregivers, thereby having a negative impact on the caregivers’ quality of life. There is evidence that suggests that interventions aimed at caregivers, such as mindfulness, may be effective at reducing this burden and emotional issues, such as depression and anxiety, and improving their quality of life. However, there is a lack of consistency in the findings and conclusions remain tentative. In addition, as neuropsychiatric symptoms (NPSs) of AD are major determinants of the caregiver’s burden, these interventions should examine the relationship between these symptoms and caregiver outcomes. Importantly, to improve the design of therapeutic interventions for caregivers and complement the treatment of AD, aspects related to occupational performance and the participation of people with AD and their caregivers should also be considered. Therefore, this study will aim to examine first, the effects of a mindfulness-based program designed for caregivers on NPSs of AD and caregivers’ anxiety and depression; second, the effects of this program on patients’ functional capacity, cognitive performance, executive functions, and quality of life, and on caregivers’ burden, quality of life, occupational balance, executive functions, psychological wellbeing, and self-compassion. We believe that the findings of this study will have significant implications for future healthcare strategies focused on improving the quality of life and wellbeing of caregivers.

The effect of concomitant benzodiazepine use on neurocognition in stable, long-term patients with bipolar disorder

OBJECTIVE

Neurocognitive dysfunction is a common feature of bipolar disorder even in euthymia, and psychopharmacological treatment could have an effect on cognition. Long-term prescription of benzodiazepines in bipolar disorder is a common practice, and their effect on neurocognition has not been well studied in this population. The aim of this study was to evaluate the impact of concomitant benzodiazepine long-term use on neurocognitive function in stable euthymic bipolar disorder patients.

METHODS

Seventy-three euthymic bipolar disorder outpatients and 40 healthy individuals were assessed using a neurocognitive battery. Patients were classified in two groups according to the presence of benzodiazepines in their treatment: the benzodiazepine group (n = 34) and the non- benzodiazepine group (n = 39). Neurocognitive performance was compared between the groups using a multivariate analysis of covariance, considering age, number of depressive episodes, adjuvant antipsychotic drugs, Young Mania Rating Scale score and Hamilton Depression Rating Scale score as covariates.

RESULTS

Both bipolar disorder groups (benzodiazepine and non-benzodiazepine) showed an impairment in memory domains (Immediate Visual Memory [p = 0.013], Working Memory [p < 0.001], and Letter-Number Sequence [p < 0.001] from the Wechsler Memory Scale-Revised-III) and slower processing speed functions (Stroop Colour [p < 0.001]) relative to the control group. Nevertheless, the benzodiazepine group showed a greater impairment in executive functions (Conceptual Level Responses [p = 0.024] from the Wisconsin Card Sorting Test and Frontal Assessment Battery [p = 0.042]).

CONCLUSION

Although memory and processing speed impairments were found in bipolar disorder, regardless of their benzodiazepine treatment, benzodiazepine users presented additional neurocognitive impairments in terms of executive functioning. These findings support restricted prescription of benzodiazepines in individuals with bipolar disorder.

The Frontal Assessment Battery 20 years later: normative data for a shortened version (FAB15)

OBJECTIVE

The Frontal Assessment Battery (FAB) is a neuropsychological tool largely used to assess executive functions. Prior studies found a marked ceiling effect for the prehension behavior subtest (PBT) in healthy and clinical populations. Aims of the present study were (i) to examine the psychometric properties of the FAB without the contribution of PBT and (ii) to provide normative data for a revised version of the FAB after exclusion of PBT (FAB15).

METHODS

The normative sample included 1,187 healthy participants. PBT had near-zero variance, poor content validity, and no discrimination power. Internal consistency increased when PBT was excluded. We assessed the FAB15 factorial structure, interrater, and test-retest reliabilities. Normative data  for the FAB15 were extracted through a regression-based procedure according to sex, age, and education.

RESULTS

The principal component analysis revealed a single "executive factor" or alternatively a bifactorial solution reflecting the different degree of discriminative capability vs. difficulty of the subtests. The FAB15 demonstrated excellent interrater and test-retest reliabilities. Regression analysis showed that sex (lowly educated women < lowly educated men), higher age, and lower education affected FAB15 score. Accordingly, three grids for adjustment of raw scores (men, women, and both) were constructed. The cut-off was fixed at the non-parametric outer tolerance limit on the fifth centile (9.36, 95% CI).

CONCLUSION

The observation of a ceiling effect in healthy subjects makes PBT not suitable for inclusion in a neuropsychological battery. The FAB15 may successfully replace the conventional FAB as a more severe and valid short screening tool to assess executive functioning.

EEG-Derived Functional Connectivity Patterns Associated with Mild Cognitive Impairment in Parkinson's Disease

OBJECTIVE

To evaluate EEG-derived functional connectivity (FC) patterns associated with mild cognitive impairment (MCI) in Parkinson's disease (PD).

METHODS

A sample of 15 patients without cognitive impairment (PD-WCI), 15 with MCI (PD-MCI), and 26 healthy subjects were studied. The EEG was performed in the waking functional state with eyes closed, for the functional analysis it was used the synchronization likelihood (SL) and graph theory (GT).

RESULTS

PD-MCI patients showed decreased FC in frequencies alpha, in posterior regions, and delta with a generalized distribution. Patients, compared to the healthy people, presented a decrease in segregation (lower clustering coefficient in alpha p = 0.003 in PD-MCI patients) and increased integration (shorter mean path length in delta (p = 0.004) and theta (p = 0.002) in PD-MCI patients). There were no significant differences in the network topology between the parkinsonian groups. In PD-MCI patients, executive dysfunction correlated positively with global connectivity in beta (r = 0.47) and negatively with the mean path length at beta (r = -0.45); alterations in working memory were negatively correlated with the mean path length at beta r = -0.45.

CONCLUSIONS

PD patients present alterations in the FC in all frequencies, those with MCI show less connectivity in the alpha and delta frequencies. The neural networks of the patients show a random topology, with a similar organization between patients with and without MCI. In PD-MCI patients, alterations in executive function and working memory are related to beta integration.

Adaptation of the Spanish version of the Frontal Assessment Battery for detection of executive dysfunction

BACKGROUND

The Frontal Assessment Battery (FAB) evaluates executive dysfunctions; however, there is no culturally adapted version of this instrument for the Spanish population. The aim of this study was the translation and cross-cultural adaptation of the original version of the FAB into Spanish and to pilot test this version.

METHODS

The cross-cultural adaptation was conducted following standard procedures. The final Spanish version of the FAB (FAB-E) was pilot tested with 19 healthy Spanish individuals. Total and subtest FAB-E scores were analysed to verify that the test could be understood and that the items assessed what they were intended to assess.

RESULTS

The FAB-E revealed that items/instructions were culturally appropriate and written clearly. Pilot testing showed that most of the participants had scores ranging between 2 and 3 points in all the items. The mean of the total FAB-E was 15.8 (SD=1.3) and the values ranged from 13 to 18. Age and educational level seemed to indicate differences in FAB-E scores.

CONCLUSION

Our findings support that the FAB-E can be used to screen for executive dysfunctions in a Spanish-speaking population.

Clinical Characterization of Parkinson's Disease Patients With Cognitive Impairment

Background: Cognitive impairment is one of the most frequent and disabling non-motor symptoms in Parkinson disease (PD) and encompasses a continuum from mild cognitive impairment (PD-MCI) to dementia (PDD). The risk factors associated with them are not completely elucidated. Objective: To characterize the presence and clinical presentation of PD-MCI and PDD in patients with idiopathic PD, examining motor and non-motor features and determining factors associated with cognitive impairment. Methods: Multicenter, cross-sectional study in 298 PD patients who underwent clinical [Hoehn and Yahr (HY) staging and Clinical Impression of Severity Index for Parkinson Disease], neurological [Scales for Outcomes in Parkinson's Disease (SCOPA)-Motor], neuropsychological (Mini Mental State Examination, SCOPA-Cognition, Frontal Assessment Battery and Clinical Dementia Rating Scale), neuropsychiatric [SCOPA-Psychiatric complications, SCOPA-Psychosocial (SCOPA-PS), and Hospital Anxiety and Depression Scale (HADS)], and health-related quality of life [Parkinson Disease Questionnaire for quality of life (PDQ-8)] assessment. Movement Disorders Society criteria were applied to classify patients as normal cognition (NC), PD-MCI, and PDD. The association between variables was explored using multivariate binary and multinomial logistic regression models. Results: Seventy-two patients (24.2%) were classified as NC, 82 (27.5%) as PD-MCI, and 144 (48.3%) as PDD. These last two groups reported more psychosocial problems related with the disease (mean SCOPA-PS, 16.27 and 10.39, respectively), compared with NC (7.28) and lower quality-of-life outcomes (PDQ-8 48.98 and 28.42, respectively) compared to NC (19.05). The logistic regression analysis showed that both cognitive impaired groups had a more severe stage of PD measured by HY [odds ratio (OR) for MCI-PD, 2.45; 95% confidence interval (CI), 1.22-4.90; OR for PDD 2.64; 95% CI, 1.17-5.98]. Specifically, age (OR, 1.30; 95% CI, 1.16-1.47), years of education (OR, 0.91; 95% CI, 0.83-0.99), disease duration (OR, 1.19; 95% CI, 1.07-1.32), HADS-D (OR, 1.20; 95% CI, 1.06-1.35), and hallucinations (OR, 2.98; 95% CI, 1.16-7.69) were related to PDD. Conclusions: Cognitive impairment in PD is associated with more severe disease stage, resulting in a global, neuropsychiatric, psychosocial, and quality-of-life deterioration. This study provides a better understanding of the great impact that cognitive impairment has within the natural history of PD and its relationship with the rest of motor and non-motor symptoms in the disease.

SNCA rs11931074 polymorphism correlates with spontaneous brain activity and motor symptoms in Chinese patients with Parkinson's disease

The α-synuclein (SNCA) gene is thought to be involved in levels of α-synuclein and influence the susceptibility for the development of Parkinson's disease (PD). The aim of the present study is to explore the association among SNCA rs1193074 polymorphism, spontaneous brain activity and clinical symptoms in PD patients. 62 PD patients and 47 healthy controls (HC) were recruited and underwent resting-state functional magnetic resonance imaging (rs-fMRI) scans. Also blood sample of each participant was genotyped for rs11931074 polymorphism (PD: TT = 19, GT = 32, GG = 11; HC: TT = 10, GT = 25, GG = 12) and then examined to ascertain the influence of different genotypes on regional brain activity with amplitude low-frequency fluctuation analysis (ALFF). Furthermore, we evaluated the relationship among genotypes, interactive brain region and clinical symptoms in PD. Compared with HC subjects, PD patients showed decreased ALFF values in right lingual gyrus and increased ALFF values in right cerebellum posterior lobe. Significant interaction of ''groups × genotypes'' was found in the right angular gyrus, where there were higher ALFF values in TT genotype than in GT or GG genotype in the PD group and there was a contrary trend in the HC group. And further Spearman's correlative analyses revealed that ALFF values in right angular gyrus were negatively associated with unified Parkinson's disease rating scale (UPDRS) III score in PD-TT genotype. Our study shows for the first time that SNCA rs11931074 polymorphism might modulate brain functional alterations and correlate with motor symptoms in Chinese PD patients.