Dawn M. Schiehser

Complex activities of daily living vary by mild cognitive impairment subtype

There is increasing consensus regarding the importance of operationally defining and measuring functional decline in mild cognitive impairment (MCI). However, few studies have directly examined functional abilities in MCI or its presumed subtypes and, to date, reported findings have been discrepant. Nondemented older adults (n = 120) were administered a comprehensive cognitive battery measuring multiple domains as well as a performance-based functional ability measure. Participants were characterized as either cognitively normal, amnestic MCI, or non-amnestic MCI. MCI individuals demonstrated decrements in instrumental activities of daily living (IADL) relative to their cognitively normal counterparts. Specifically, participants with amnestic MCI demonstrated significant decrements in financial management, whereas those with non-amnestic MCI showed poorer performance in abilities related to health and safety. Moreover, decreased functional abilities were associated with decrements in global cognitive functioning but not memory or executive functions in the MCI participants. Finally, logistic regression demonstrated that functional abilities accurately predicted MCI subtype. Results support the need for better delineation of functional decline in MCI. Given the implications of functional status for MCI diagnosis and treatment, the direct assessment of functional abilities is recommended. Results further suggest performance-based IADL assessment may have utility in distinguishing MCI subtypes.

Specific Measures of Executive Function Predict Cognitive Decline in Older Adults

Decline in executive function has been noted in the prodromal stage of Alzheimers disease (AD) and may presage more global cognitive declines. In this prospective longitudinal study, five measures of executive function were used to predict subsequent global cognitive decline in initially nondemented older adults. Of 71 participants, 15 demonstrated significant decline over a 1-year period on the Dementia Rating Scale (Mattis, 1988) and the remaining participants remained stable. In the year before decline, the decline group performed significantly worse than the no-decline group on two measures of executive function: the Color-Word Interference Test (CWIT; inhibition/switching condition) and Verbal Fluency (VF; switching condition). In contrast, decliners and non-decliners performed similarly on measures of spatial fluency (Design Fluency switching condition), spatial planning (Tower Test), and number-letter switching (Trail Making Test switching condition). Furthermore, the CWIT inhibition-switching measure significantly improved the prediction of decline and no-decline group classification beyond that of learning and memory measures. These findings suggest that some executive function measures requiring inhibition and switching provide predictive utility of subsequent global cognitive decline independent of episodic memory and may further facilitate early detection of dementia.

Neuropsychological test performance in patients co-infected with hepatitis C virus and HIV.

Objective:To determine the effect of co-infection on neuropsychological performance in relatively healthy hepatitis C virus (HCV)-alone patients when compared with HCV/HIV-co-infected patients. Design:To test whether the burden of co-infection with HCV and HIV on the central nervous system results in increased cognitive deficits, we tested 47 HCV-alone and 29 HCV/HIV-co-infected patients on a neuropsychological screening battery of tests of attention, concentration and psychomotor speed. Methods:The neuropsychological test performance of HCV-alone and HCV/HIV-co-infected patients was compared with normative samples. The test performance between HCV-alone and HCV/HIV-co-infected patients was also assessed. Patients with chronic liver disease were divided on the basis of disease severity as determined by fibrosis stage, according to the METAVIR system. Neuropsychological test performance was correlated with fibrosis stage. Results:As previously reported, HCV patients independent of co-infection status demonstrated deficits on neuropsychological measures of attention, concentration and psychomotor speed. No significant differences were found between patients with HCV-alone and HCV/HIV-co-infected patients on the neuropsychological measures. There was a relationship between neuropsychological test performance and fibrosis stage. Conclusion:Relatively healthy patients with HCV (either alone or when co-infected with HIV) may have deficits in the domains of attention, concentration and psychomotor speed. In this study no significant differences were found between patients with HCV alone and HCV/HIV-co-infected patients on neuropsychological measures, but as previously demonstrated, greater fibrosis was associated with poorer performance.

White matter integrity in veterans with mild traumatic brain injury: Associations with executive function and loss of consciousness

Objective:We investigated using diffusion tensor imaging (DTI) and the association between white matter integrity and executive function (EF) performance in postacute mild traumatic brain injury (mTBI). In addition, we examined whether injury severity, as measured by loss of consciousness (LOC) versus alterations in consciousness (AOC), is related to white matter microstructural alterations and neuropsychological outcome. Participants:Thirty Iraq and Afghanistan War era veterans with a history of mTBI and 15 healthy veteran control participants. Results:There were no significant overall group differences between control and mTBI participants on DTI measures. However, a subgroup of mTBI participants with EF decrements (n = 13) demonstrated significantly decreased fractional anisotropy of prefrontal white matter, corpus callosum, and cingulum bundle structures compared with mTBI participants without EF decrements (n = 17) and control participants. Participants having mTBI with LOC were more likely to evidence reduced EF performances and disrupted ventral prefrontal white matter integrity when compared with either mTBI participants without LOC or control participants. Conclusions:Findings suggest that altered white matter integrity contributes to reduced EF in subgroups of veterans with a history of mTBI and that LOC may be a risk factor for reduced EF as well as associated changes to ventral prefrontal white matter.

Validation of the Modified Fatigue Impact Scale in Parkinson's disease

INTRODUCTION Fatigue is a common symptom in Parkinsons disease (PD); however, a multidimensional scale that measures the impact of fatigue on functioning has yet to be validated in this population. The aim of this study was to examine the validity of the Modified Fatigue Impact Scale (MFIS), a self-report measure that assesses the effects of fatigue on physical, cognitive, and psychosocial functioning, in a sample of nondemented PD patients. METHODS PD patients (N = 100) completed the MFIS, the Positive and Negative Affect Schedule (PANAS-X), and several additional measures of psychosocial, cognitive, and motor functioning. A Principal Component Analysis (PCA) and item analysis using Cronbachs alpha were conducted to determine structural validity and internal consistency of the MFIS. Correlational analyses were performed between the MFIS and the PANAS-X fatigue subscale to evaluate convergent validity and between the MFIS and measures of depression, anxiety, apathy, and disease-related symptoms to determine divergent validity. RESULTS The PCA identified two viable MFIS subscales: a cognitive subscale and a combination of the original scales physical and psychosocial subscales as one factor. Item analysis revealed high internal consistency of all 21 items and the items within the two subscales. The MFIS had strong convergent validity with the PANAS-X fatigue subscale and adequate divergent validity with measures of disease stage, motor function, and cognition. CONCLUSION Overall, this study demonstrates that the MFIS is a valid multidimensional measure that can be used to evaluate the impact of fatigue on cognitive and physical/social functioning in PD patients without dementia.

Executive functioning in older adults with hoarding disorder

Hoarding disorder (HD) is a chronic and debilitating psychiatric condition. Midlife HD patients have been found to have neurocognitive impairment, particularly in areas of executive functioning, but the extent to which this is due to comorbid psychiatric disorders has not been clear.

Instrumental activities of daily living are impaired in Parkinson’s disease patients with mild cognitive impairment.

OBJECTIVE Although it is well known that Parkinsons disease (PD) with dementia results in functional decline, little is known about the impact of mild cognitive impairment in PD (PD-MCI) on day-to-day functioning. METHOD Forty-one individuals with PD-MCI, 56 PD patients with normal cognition (PD-NC), and 47 healthy older adults were administered two performance-based measures of instrumental activities of daily living (IADLs) that evaluated medication and financial management. Informants of the PD patients were also administered an IADL questionnaire. RESULTS There were no significant differences between PD-NC and healthy older adults on the performance-based measures of medication and financial management. However, PD-MCI patients demonstrated significantly lower scores on the performance-based measures of medication and financial management compared with healthy older adults. PD-MCI patients were also impaired compared with PD-NC patients on performance-based medication management, but no difference between these groups was observed for ability to manage finances. Performance-based financial and medication management did not correlate with scores on neuropsychological measures in PD-MCI patients. PD-MCI and PD-NC patients showed comparable scores on the informant-based IADL questionnaire. CONCLUSIONS Performance-based measures of IADLs, particularly medication management ability, are sensitive to subtle functional declines in PD-MCI. Although impairment in performance-based measures is associated with cognitive status in PD, IADLs may be a separate domain of functioning from cognitive functioning in PD-MCI as these measures did not correlate with performance on the neuropsychological measures. Overall, performance-based assessment of IADLs may add to the clinical evaluation of PD-MCI.

The utility of the Mattis Dementia Rating Scale in Parkinson's disease mild cognitive impairment

BACKGROUND The Movement Disorders Society (MDS) recently proposed guidelines for diagnosis of mild cognitive impairment in Parkinsons disease (PD-MCI) that includes two assessment levels: abbreviated (Level I) and comprehensive (Level II). The aim of this study was to determine the utility of the Mattis Dementia Rating Scale (MDRS), a recommended Level I test, for detecting Level II PD-MCI diagnosis. METHODS The study sample included 30 patients diagnosed with PD-MCI based on Level II MDS criteria and 68 PD patients with normal cognition (PD-NC). Receiver operator curve (ROC) analyses were generated to measure the sensitivity and specificity of various MDRS cutoff scores. To examine the utility of the MDRS as a screening tool, the optimal cutoff point was defined as the lowest value providing ≥80% sensitivity. For use of the MDRS as a diagnostic tool, the optimal cutoff point was defined as the highest value providing ≥80% specificity. RESULTS ROC analyses showed that the optimal MDRS cutoff score for screening purposes and diagnostic purposes were ≤140 and ≤137, respectively. However, an examination of sensitivity/specificity values for the screening cutoff scores suggested that a total score of ≤139 for screening purposes yielded a better balance between sensitivity (77%) and specificity (65%). CONCLUSIONS In a clinical setting, in which detection of PD-MCI may be important, a total MDRS score of ≤139 can be used to detect PD-MCI. In research and other settings in which diagnostic certainty is more important, a score of ≤137 may be more useful.

Neuropsychological performance in treatment-seeking Operation Enduring Freedom/Operation Iraqi Freedom Veterans with a history of mild traumatic brain injury

Introduction: Clinical neuropsychological presentation of treatment-seeking Veterans with a remote history of mild traumatic brain injury (mTBI) is widely variable. This manuscript seeks to better characterize cognitive concerns in the post-acute phase following mTBI and to identify the neuropsychological profiles of a large sample of clinically referred Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn (OEF/OIF/OND) Veterans with a history of mTBI and current cognitive complaints. We hypothesized that a minority of cases would exhibit valid and widespread neuropsychological deficits. Method: Retrospective chart reviews of neuropsychological testing and mental health symptoms and diagnoses were conducted on 411 clinically referred OEF/OIF/OND Veterans with a history of mTBI. Groups were created based on scores on performance validity measures and based on overall neuropsychological performance. Results: A total of 29.9% of the sample performed below normative expectations on at least one performance validity test (PVT). Of those Veterans performing adequately on PVTs, 60% performed within normal limits on virtually all neuropsychological measures administered, leaving only 40% performing below expectations on two or more measures. Mood and neurobehavioral symptoms were significantly elevated in Veterans performing below cutoff on PVTs compared to Veterans who performed within normative expectations or those with valid deficits. Neurobehavioral symptoms were significantly correlated with mental health symptom reports but not with injury variables. Conclusions: In summary, in a large sample of clinically referred Veterans with persistent cognitive complaints after mild TBI, a third demonstrated invalid clinical neuropsychological testing, and, of those performing at or above cutoff on PVTs, over half performed within normative expectations across most neuropsychological tests administered. Results highlight the importance of objective assessment of cognitive functioning in this population as subjective reports do not correspond to objective assessment in the majority of cases.

The Relationship Between Postconcussive Symptoms and Quality of Life in Veterans With Mild to Moderate Traumatic Brain Injury

Objective:To assess the relationship between postconcussive symptoms and quality of life (QOL) in Veterans with mild to moderate traumatic brain injury (TBI). Methods:Sixty-one Operation Enduring Freedom/Operation Iraqi Freedom/Persian Gulf War Veterans with a history of mild or moderate TBI, more than 6 months postinjury, and 21 demographically matched Veteran controls were administered self-report measures of QOL (World Health Organization Quality of Life–BREF) and postconcussive symptom severity (Neurobehavioral Symptom Inventory). Results:Perceived QOL was significantly worse in Veterans with mild-moderate TBI than in controls. In the TBI group, QOL was predominantly associated with affective symptoms, and moderate to strong correlations with fatigue and depression were evident across all QOL areas. Multivariate analyses revealed depression and fatigue to be the best predictors of Psychological, Social, and Environmental QOL, whereas sleep difficulty best predicted Physical QOL in mild-moderate TBI. Conclusion:Veterans with post–acute mild-moderate TBI evidence worse QOL than demographically matched Veteran controls. Affective symptoms, and specifically those of fatigue, depression, and sleep difficulty, appear to be the most relevant postconcussive symptoms predicting QOL in this population. These findings underscore the importance of examining specific symptoms as they relate to post–acute TBI QOL and provide guidance for treatment and intervention studies.