The relationship between objective and subjective executive function in Parkinson's disease.

INTRODUCTION: Difficulties in executive functioning (EF) are common in PD; however, the relationship between subjective and objective EF is unclear. Understanding this relationship could help guide clinical EF assessment. This study examined the relationship between subjective self-reported EF (SEF) and objective EF (OEF) and predictors of SEF-OEF discrepancies in PD. METHOD: One-hundred and sixteen non-demented PD participants completed measures of OEF (i.e. problem-solving, cognitive flexibility, inhibition, and working memory) and SEF (Frontal Systems Behavior Scale-Self Executive Dysfunction Subscale). Pearson bivariate correlations and linear regressions were performed to examine the relationship between SEF and OEF and the non-motor symptoms (e.g. mood, fatigue), demographic, and PD characteristic (e.g. MCI status) predictors of discrepancies between OEF and SEF (|OEF minus SEF scores|). Correlates of under-, over-, and accurate-reporting were also explored. RESULTS: Greater SEF complaints and worse OEF were significantly associated (ß =.200, p = .009) and 64% of participants accurately identified their level of OEF abilities. Fewer years of education and greater symptoms of depression, anxiety, and fatigue significantly correlated with greater discrepancies between OEF and SEF. Fatigue was the best predictor of EF discrepancy in the overall sample (ß = .281, p = .022). Exploratory analyses revealed apathy and fatigue associated with greater under-reporting, while anxiety associated with greater over-reporting. CONCLUSIONS: SEF and OEF are significantly related in PD. Approximately 64% of non-demented persons with PD accurately reported their EF skill level, while 28% under-reported and 8% over-reported. SEF-OEF discrepancies were predicted by fatigue in the overall sample. Preliminary evidence suggests reduced apathy and fatigue symptoms relate to more under-reporting, while anxiety relates to greater over-reporting. Given the prevalence of these non-motor symptoms in PD, it is important to carefully consider them when assessing EF in PD.

Prospective predictors of care partner burden and depression in Parkinson's disease.

OBJECTIVES: Care partners who provide informal care to individuals with Parkinson's disease (PD) report higher levels of burden and depression; however, longitudinal research on these symptoms is scarce. The current study assessed changes in care partner burden and depression, and patient and care partner predictors of these symptoms over time. Such knowledge may provide important information for assessment and treatment of depression and burden in care partners of individuals with PD. RESEARCH DESIGN AND METHODS: Participants were 88 PD patients without dementia and their self-identified care partner (n = 88). Care partners completed the Geriatric Depression Scale and Zarit Burden Interview. PD participants completed mood questionnaires and a motor exam at baseline and 2 year follow-up. Relationships among care partner burden and depression over time with patient and care partner predictors (i.e., demographic, mood, and disease characteristics) were assessed using correlations and regression analyses. RESULTS: Care partner burden and depression significantly increased over an approximate 2 year period. Greater baseline disease severity predicted worsening of care partner burden (p = 0.028), while baseline patient depression predicted worsening of care partner depression (p = 0.002). CONCLUSIONS: Results highlight differential impacts of specific PD symptoms on worsening care partner burden compared to depression; increased PD disease severity predicts increased burden, while patient mood predicts worsening of depression over time. Targeting PD disease severity and mood symptoms may prevent the progression of care partner burden and depression.

Changes in Self- and Informant-Reported Frontal Behaviors in Parkinson's Disease: A Longitudinal Study.

OBJECTIVE: Frontal behaviors (i.e., executive dysfunction, disinhibition, apathy) are common in Parkinson's disease (PD). However, it is unclear if patient and informant reports of patient frontal behaviors are in agreement over time. METHOD: Sixty-two PD patients without dementia and their informants (87% spouses/partners) completed the self- and informant-versions of the Frontal Systems Behavior Scale at baseline and 2-year follow-up. Dyad ratings were compared and predictors of behavior ratings were examined. RESULTS: Patient and informant reports at baseline and follow-up were in agreement, with significant increases in overall frontal behaviors, executive dysfunction, and apathy. Higher levels of baseline patient depression and caregiver burden predicted decrements in patient-reported executive function; worse patient cognition at baseline predicted worsening apathy as rated by informants. CONCLUSIONS: PD patients and their informants are concordant in their ratings of worsening frontal behaviors over time. Targeting patient depression, cognition, and caregiver burden may improve decrements in frontal behaviors (executive dysfunction and apathy) in PD.

Evaluation of ReminX as a Behavioral Intervention for Mild to Moderate Dementia.

Dementia is a growing global challenge that is difficult to treat. Pharmaceutical treatment approaches have had limited success, leading to an increased focus on nonpharmaceutical approaches to the treatment of dementia. A clinical pilot study was performed to evaluate whether ReminX digital therapeutic software, based on reminiscence therapy, has the potential to improve emotional functioning in patients with Alzheimer's disease and related dementias. ReminX allows the uploading of pictures and narration to create slideshow stories depicting important moments in the patient's life. Fourteen patients were evaluated in their home, and their emotional health was assessed both before and after using ReminX. Results indicated that patients reported significantly less anxiety, depression, and overall emotional distress after having viewed their story. Furthermore, patient's caregivers also reported that the patient appeared less emotionally distressed. The effect sizes for the significant results ranged from 0.76 to 0.91. These effect sizes, which were larger than anticipated, suggest that digitally-delivered reminiscence therapy can have an immediate and positive impact on emotional functioning in patients with dementia. In addition, the accessibility, scalability, and ease of use of the software platform suggests that this technology holds great promise as a product for use in both the home and senior care settings.

Does the Geriatric Depression Scale measure depression in Parkinson's disease?

The Geriatric Depression Scale (GDS) is recommended for screening depression in individuals with Parkinson's disease (PD). Empirical evidence, however, is limited regarding its validity and factor structure in PD. Thus, the current study sought to evaluate the convergent and divergent validity of the GDS, as well as the structure and validity of the derived factors. METHOD: Nondemented individuals with PD (n = 158) completed the GDS-30, and items were subjected to a principle component analysis. Geriatric Depression Scale total and factor scores were correlated with depression items from the Movement Disorder Society Unified Parkinson's disease Rating Scale (MDS-UPDRSd) and Hamilton Rating Scale for Depression (HAMDd), as well as with the Apathy Scale (AS), State-Trait Anxiety Inventory (STAI), Modified Fatigue Impact Scale (MFIS), Parkinson's disease Sleep Scale, and a Subjective Cognitive Function composite score. RESULTS: The GDS total score was strongly correlated with divergent neuropsychiatric measures (AS, r = 0.57; STAI, r = 0.66; MFIS, r = 0.60), while only moderately correlated with convergent measures (MDS-UPDRSd, r = 0.36; HAMDd, r = 0.32; Ps < 0.05). Linear regression analyses revealed standardized measures of anxiety, apathy, and fatigue independently predicted the GDS total score, while depression items (MDS-UPDRSd and HAMDd) failed to reach significance. Three independent factors were identified: Anxiety, Apathy, and Fatigue. These factors were significantly predicted by their respective convergent measures. CONCLUSIONS: Taken together, our findings suggest that the GDS and its subscales appear to primarily measure anxiety, apathy, and fatigue in PD, or alternatively, these symptom dimensions may be predominant in PD-depression. Future research with clinically diagnosed samples is needed to confirm these initial findings.

Anhedonia and individual differences in orbitofrontal cortex sulcogyral morphology.

Three types of orbitofrontal cortex (OFC) sulcogyral patterns that have been identified in the population, and the distribution of these three types in clinically diagnosed schizophrenic patients has been found to be distinct from the normal population. Schizophrenia is associated with increased levels of social and physical anhedonia. In this study, we asked whether variation in anhedonia in a neurologically normal population is associated with altered sulcogyral pattern frequency. OFC sulcogyral type was classified and anhedonia was measured in 58 normal young adults, and the relationship between OFC sulcogyral type and anhedonia was explored. In line with other studies conducted in chronic schizophrenia, individuals with higher levels of physical anhedonia demonstrated atypical sulcogyral patterns. Individuals with higher physical anhedonia showed a reduced incidence of Type I OFC and an increased incidence of Type II OFC in the left hemisphere compared to individuals with lower physical anhedonia. These findings support the notion that Type I OFC sulcogyral pattern is protective of anhedonia compared to Type II, even in individuals that are not schizophrenic. Overall, these results support the view that symptoms and neural indices typically associated with neuropsychiatric disorders actually reflect quantitative traits that are continuously distributed throughout the general population. Hum Brain Mapp 37:3873-3881, 2016. © 2016 Wiley Periodicals, Inc.