The detection of dementia and cognitive impairment in a community population of elderly people with Parkinson's disease by use of the CAMCOG neuropsychological test

Profiles of Motor-Cognitive Interference in Parkinson's Disease-The Trail-Walking-Test to Discriminate between Motor Phenotypes

Background and Aims. Most research on Parkinson’s disease (PD) focuses on describing symptoms and movement characteristics. Studies rarely focus on the early detection of PD and the search for suitable markers of a prodromal stage. Early detection is important, so treatments that may potentially change the course of the disease can be attempted early on. While gait disturbances are less pronounced in the early stages of the disease, the prevalence, and severity increase with disease progression. Therefore, postural instability and gait difficulties could be identified as sensitive biomarkers. The aim was to evaluate the discriminatory power of the Trail-Walking Test (TWT; Schott, 2015) as a potential diagnostic instrument to improve the predictive power of the clinical evaluation concerning the severity of the disease and record the different aspects of walking. Methods. A total of 20 older healthy (M = 72.4 years, SD = 5.53) adults and 43 older adults with PD and the motor phenotypes postural instability/gait difficulty (PIGD; M = 69.7 years, SD = 8.68) and tremor dominant (TD; M = 68.2 years, SD = 8.94) participated in the study. The participants performed a motor-cognitive dual task (DT) of increasing cognitive difficulty in which they had to walk a given path (condition 1), walk to numbers in ascending order (condition 2), and walk to numbers and letters alternately and in ascending order (condition 3). Results. With an increase in the cognitive load, the time to complete the tasks (seconds) became longer in all groups, F(1.23, 73.5) = 121, p < 0.001, ɳ2p = 0.670. PIGD showed the longest times in all conditions of the TWT, F(2, 60) = 8.15, p < 0.001, ɳ2p = 0.214. Mutual interferences in the cognitive and motor domain can be observed. However, clear group-specific patterns cannot be identified. A differentiation between the motor phenotypes of PD is especially feasible with the purely motor condition (TWT-M; AUC = 0.685, p = 0.44). Conclusions. PD patients with PIGD must be identified by valid, well-evaluated clinical tests that allow for a precise assessment of the disease’s individual fall risk, the severity of the disease, and the prognosis of progression. The TWT covers various aspects of mobility, examines the relationship between cognitive functions and walking, and enables differentiation of the motor phenotypes of PD.

Dementia-Free Survival and Risk Factors for Dementia in a Hospital-Based Korean Parkinson's Disease Cohort

Background and Purpose

Few studies of dementia in Parkinson's disease (PD) have had long-term follow-ups. Moreover, information on the duration from the onset to the development of dementia in patients with PD is lacking. The aim of this study was to determine the median dementia-free survival time from the onset of PD to the development of dementia.

Methods

In total, 1,193 Korean patients with PD were recruited and assessed at regular intervals of 3–6 months. We interviewed the patients and other informants to identify impairments in the activities of daily living. The Hoehn and Yahr stage and scores on the Unified Parkinson's Disease Rating Scale and Mini Mental State Examination were evaluated annually. We used Kaplan-Meier survival analysis to estimate the cumulative proportion of dementia-free patients over time. Risk factors predicting dementia were also evaluated using Cox proportional-hazards regression models.

Results

The median dementia-free survival time in the Korean PD population was 19.9 years. Among the 119 patients who subsequently developed dementia, the mean duration from the onset of PD to the development of dementia was 10.6 years. A multivariate analysis identified age at onset and education period as the significant predictors of dementia.

Conclusions

This is the first report on dementia-free survival in patients with PD based on longitudinal data analysis from the disease onset. The median dementia-free survival time in Korean PD patients was found to be longer than expected.

Higher Plasma LDL-Cholesterol is Associated with Preserved Executive and Fine Motor Functions in Parkinson's Disease

Plasma low density lipoprotein (LDL) cholesterol has been associated both with risk of Parkinson's disease (PD) and with age-related changes in cognitive function. This prospective study examined the relationship between baseline plasma LDL-cholesterol and cognitive changes in PD and matched Controls. Fasting plasma LDL-cholesterol levels were obtained at baseline from 64 non-demented PD subjects (62.7 ± 7.9 y) and 64 Controls (61.3 ± 6.8 y). Subjects underwent comprehensive neuropsychological testing at baseline, 18-, and 36-months. Linear mixed-effects modeling was used to assess the relationships between baseline LDL-cholesterol levels and longitudinal cognitive changes. At baseline, PD patients had lower scores of fine motor (p<0.0001), executive set shifting (p=0.018), and mental processing speed (p=0.049) compared to Controls. Longitudinally, Controls demonstrated improved fine motor and memory test scores (p=0.044, and p=0.003), whereas PD patients demonstrated significantly accelerated loss in fine motor skill (p=0.002) compared to Controls. Within the PD group, however, higher LDL-cholesterol levels were associated with improved executive set shifting (β=0.003, p<0.001) and fine motor scores (β=0.002, p=0.030) over time. These associations were absent in Controls (p>0.7). The cholesterol - executive set shifting association differed significantly between PDs and Controls (interaction p=0.005), whereas the cholesterol - fine motor association difference did not reach significance (interaction, p=0.104). In summary, higher plasma LDL-cholesterol levels were associated with better executive function and fine motor performance over time in PD, both of which may reflect an effect on nigrostriatal mediation. Confirmation of these results and elucidation of involved mechanisms are warranted, and might lead to feasible therapeutic strategies.

History of smoking and olfaction in Parkinson's disease

OBJECTIVE

Olfactory dysfunction is the most common pre-motor symptom in Parkinson's disease (PD), and smoking is known to be associated with lower risk of PD. This study tested the hypothesis that smoking is associated with better olfaction in PD.

METHODS

Smoking history was obtained from 76 PD subjects (22 with a history of smoking [smokers], 54 who never smoked [nonsmokers]), and 70 controls (17 smokers, 53 nonsmokers). Olfaction was assessed using the 40-item University of Pennsylvania Smell Identification Test (UPSIT). The olfactory scores between groups and subgroups were compared using analysis of covariance with adjustment for age, gender, and monoamine oxidase B (MAO-B) inhibitor usage.

RESULTS

Overall the olfactory score was lower in PD compared with controls (olfactory scores: 21.5 vs. 33.5, P < 0.0001). Among controls, there was no significant difference in olfaction between smokers and nonsmokers (olfactory scores, 33.2 vs. 34.2; P = 0.95). Among PD subjects, however, smokers scored significantly better regarding olfaction compared with nonsmokers (olfactory scores: 24.4 vs. 19.9, P = 0.02).

CONCLUSIONS

These data suggest that a history of smoking is associated with better olfaction among PD patients. The finding may be related to why smoking may be protective against PD. Further studies are needed to confirm this finding and investigate the underlying mechanisms.

A pilot evaluation of a brief non-verbal executive function assessment in Parkinson's disease

OBJECTIVE

Screening for cognitive impairment in the clinical or community setting is often hampered by the lack of a suitable assessment that is not overburdened with complex administration and scoring methods. We have developed non-verbal cognitive screening instrument: the Weigl Token Test (WTT) from two existing instruments, the Weigl's Colour-Form Sorting Test (WCFST) and the Token Test. The aim of this investigation is to compare the modified WTT with a battery of 'Gold Standard' cognitive assessments, to determine its utility, sensitivity and specificity as a brief cognitive screen in a cohort of Parkinson's disease (PD) patients.

METHODS

A total of 50 PD patients consented to participate in this investigation. All participants were assessed with a battery of cognitive screening instruments including the WCFST, Mini Mental Status Examination, Addenbrooke's Cognitive Examination--Revised and Delis Kaplan Executive Function Systems. The sensitivity and specificity of the WTT to detect cognitive impairment were based upon psychiatric interview, neuropsychological assessment and application of DSM-IV criteria.

RESULTS

The optimal cut-point of the WTT was 116/120, and its sensitivity and specificity to detect cognitive impairment were 88% and 89%, respectively. The diagnostic accuracy of the WTT as calculated by the area under the receiver operating curve was 0.83 (95% CI 0.76-0.95), suggesting that this instrument has acceptable psychometric properties to discriminate between case and non-cases of cognitive impairment.

CONCLUSIONS

The WTT demonstrated excellent concurrent validity with existing 'Gold Standard' assessments of cognitive impairment. We believe that this instrument will prove to be a valuable additional screening assessment in epidemiological, primary care, specialist mental health or clinical investigations.

Addenbrooke's Cognitive Examination-Revised is accurate for detecting dementia in Parkinson's disease patients with low educational level

Diagnosis of Parkinson's disease dementia is a challenge in clinical settings. A comprehensive neuropsychological evaluation is time-consuming and expensive; brief instruments for cognitive evaluation must be easier to administer and provide a reliable classification.

Objective

To study the validity of the Brazilian version of Addenbrooke's Cognitive Examination-Revised (ACE-R) for the cognitive assessment of Parkinson's disease (PD) patients with heterogeneous educational level.

Methods

Patients were evaluated according to the diagnostic procedures recommended by the Movement Disorder Society (MDS) as the gold standard for the diagnosis of dementia in PD.

Results

We studied 70 idiopathic PD patients, with a mean (SD) age of 64.1 (9.3) years and mean disease duration of 7.7 (5.3) years and educational level of 5.9 years, matched for education and age to controls. Twenty-seven patients fulfilled MDS clinical criteria for PD dementia. Mean scores on the ACE-R were 54.7 (12.8) points for patients with PD dementia, 76 (9.9) for PD patients without dementia and 79.7 (1.8) points for healthy controls. The area under the receiver operating curve, taking the MDS diagnostic procedures as a reference, was 0.93 [95% CI, 0.87-0.98; p<0.001] for ACE-R. The optimal cut-off value for ACE-R was ≤72 points [sensitivity 90%; specificity 85%; Kappa concordance (K) 0.79].

Conclusion

ACE-R appears to be a valid tool for dementia evaluation in PD patients with heterogeneous educational level, displaying good correlation with clinical criteria and diagnostic procedures of the MDS.

Process mining for individualized behavior modeling using wireless tracking in nursing homes

The analysis of human behavior patterns is increasingly used for several research fields. The individualized modeling of behavior using classical techniques requires too much time and resources to be effective. A possible solution would be the use of pattern recognition techniques to automatically infer models to allow experts to understand individual behavior. However, traditional pattern recognition algorithms infer models that are not readily understood by human experts. This limits the capacity to benefit from the inferred models. Process mining technologies can infer models as workflows, specifically designed to be understood by experts, enabling them to detect specific behavior patterns in users. In this paper, the eMotiva process mining algorithms are presented. These algorithms filter, infer and visualize workflows. The workflows are inferred from the samples produced by an indoor location system that stores the location of a resident in a nursing home. The visualization tool is able to compare and highlight behavior patterns in order to facilitate expert understanding of human behavior. This tool was tested with nine real users that were monitored for a 25-week period. The results achieved suggest that the behavior of users is continuously evolving and changing and that this change can be measured, allowing for behavioral change detection.

Striatal shape in Parkinson's disease

Parkinson's disease (PD) is marked pathologically by nigrostriatal dopaminergic terminal loss. Histopathological and in vivo labeling studies demonstrate that this loss occurs most extensively in the caudal putamen and caudate head. Previous structural studies have suggested reduced striatal volume and atrophy of the caudate head in PD subjects. The spatial distribution of atrophy in the putamen, however, has not been characterized. We aimed to delineate the specific locations of atrophy in both of these striatal structures. T1- and T2-weighted brain MR (3T) images were obtained from 40 PD and 40 control subjects having no dementia and similar age and gender distributions. Shape analysis was performed using doubly segmented regions of interest. Compared to controls, PD subjects had lower putamen (p = 0.0003) and caudate (p = 0.0003) volumes. Surface contraction magnitudes were greatest on the caudal putamen (p ≤ 0.005) and head and dorsal body of the caudate (p ≤ 0.005). This spatial distribution of striatal atrophy is consistent with the known pattern of dopamine depletion in PD and may reflect global consequences of known cellular remodeling phenomena.

Applications of technology in neuropsychological assessment

Most neuropsychological assessments include at least one measure that is administered, scored, or interpreted by computers or other technologies. Despite supportive findings for these technology-based assessments, there is resistance in the field of neuropsychology to adopt additional measures that incorporate technology components. This literature review addresses the research findings of technology-based neuropsychological assessments, including computer- and virtual reality-based measures of cognitive and functional abilities. We evaluate the strengths and limitations of each approach, and examine the utility of technology-based assessments to obtain supplemental cognitive and behavioral information that may be otherwise undetected by traditional paper-and-pencil measures. We argue that the potential of technology use in neuropsychological assessment has not yet been realized, and continued adoption of new technologies could result in more comprehensive assessment of cognitive dysfunction and in turn, better informed diagnosis and treatments. Recommendations for future research are also provided.

Neuropsychology, neuroimaging or motor phenotype in diagnosis of Parkinson's disease-dementia: which matters most?

Parkinson's disease (PD) is a neurodegenerative disorder affecting not only the motor system but also the cognitive and behavioral domains. Although there are many studies addressing the issue of cognition, a universally recognized method to diagnose patients with dementia is still lacking. The aim of this study was to determine which neuropsychological test is the most reliable in the diagnosis of dementia in PD and to establish if mini mental state examination (MMSE) is enough to detect this condition. We studied 200 consecutive PD patients through an extensive neuropsychological battery, clinical evaluation and brain magnetic resonance imaging over a period of 4 years. A logistic regression model was used to evaluate the interplay between possible risk factors and the accuracy of different neuropsychological tests. PD patients with dementia performed significantly worse in all the tests as compared to patients with PD alone: phonological verbal fluency, attentional matrices, Rey auditory verbal learning test and digit span were the most useful tools. Age and disease duration were correlated with cognitive impairment. No relevant differences were detected in phenotype, affected body side at onset, levodopa equivalent daily dose or neuroimaging findings (except for the occurrence of atrophy). Despite reasonable accuracy of MMSE (90%), its positive predictive value is only 74%. Using at least 3 neuropsychological tests, among those more significant detected with logistic regression analysis, the positive predictive value rises to 91%. In conclusion, the use of an extensive neuropsychological battery is still recommended in the diagnosis of dementia in PD.

Early-stage cognitive impairment in Parkinson's disease and the influence of dopamine replacement therapy

BACKGROUND AND PURPOSE

The aim of this study was to establish the cognitive profile of newly diagnosed untreated (de novo) patients with Parkinson's disease (PD) and more advanced, treated patients, and to determine the effects of dopamine (DA) replacement therapy.

METHODS

A cohort of 23 de novo patients, 55 mild to moderately advanced, medicated PD patients and 21 healthy controls participated. Cognitive tests included the Cambridge Examination for Mental Disorders and a battery of neuropsychological tests taken from the Cambridge Neuropsychological Test Automated Battery and the Vienna Test System.

RESULTS

De novo patients with PD were more impaired in working memory strategy use than healthy controls and treated patients with PD. Furthermore, the generation of random motor behaviour was more impaired in both de novo and treated PD patients than in healthy controls. Correlation analysis revealed that in treated patients with PD, ascending doses of dopaminergic medication were associated with poorer performance on a pattern recognition task.

CONCLUSION

Selective impairments in strategy use and the generation of random motor behaviour are a very early feature of PD and might be of predictive value in further frontal cognitive deterioration. Furthermore, DA replacement therapy seems to improve frontal lobe function (strategy use) and worsen temporal lobe function (visual memory).

A review of dual-task walking deficits in people with Parkinson's disease: motor and cognitive contributions, mechanisms, and clinical implications

Gait impairments in Parkinson's disease (PD) are exacerbated under dual-task conditions requiring the simultaneous performance of cognitive or motor tasks. Dual-task walking deficits impact functional mobility, which often requires walking while performing concurrent tasks such as talking or carrying an object. The consequences of gait impairments in PD are significant and include increased disability, increased fall risk, and reduced quality of life. However, effective therapeutic interventions for dual-task walking deficits are limited. The goals of this narrative review are to describe dual-task walking deficits in people with PD, to discuss motor and cognitive factors that may contribute to these deficits, to review potential mechanisms underlying dual-task deficits, and to discuss the effect of therapeutic interventions on dual-task walking deficits in persons with PD.

Cognitive impairment in nondemented Parkinson's disease

A substantial percentage of patients with newly diagnosed Parkinson's disease without dementia are reported to be affected by cognitive impairment (CI). In practice, however, CI is underrecognized, as the signs may not be apparent in early-stage disease and many routine assessment tools lack the sensitivity to detect subtle cognitive dysfunction. Patients with PD and mild CI (MCI) may have a higher risk of developing dementia than cognitively intact PD patients; however, it is not currently known which patients with CI are at increased risk of developing dementia. This review summarizes current knowledge about CI in nondemented PD; it discusses the structural and functional changes associated with CI and addresses areas of unmet needs. We focus on questions that should be addressed in future studies to achieve consensus on its characteristics and definition, pathophysiology, epidemiology, diagnosis and assessment, and treatment and management.

MDS Task Force on mild cognitive impairment in Parkinson's disease: critical review of PD-MCI

There is controversy regarding the definition and characteristics of mild cognitive impairment in Parkinson's disease. The Movement Disorder Society commissioned a Task Force to critically evaluate the literature and determine the frequency and characteristics of Parkinson's disease-mild cognitive impairment and its association with dementia. A comprehensive PubMed literature review was conducted using systematic inclusion and exclusion criteria. A mean of 26.7% (range, 18.9%-38.2%) of nondemented patients with Parkinson's disease have mild cognitive impairment. The frequency of Parkinson's disease-mild cognitive impairment increases with age, disease duration, and disease severity. Impairments occur in a range of cognitive domains, but single domain impairment is more common than multiple domain impairment, and within single domain impairment, nonamnestic is more common than amnestic impairment. A high proportion of patients with Parkinson's disease-mild cognitive impairment progress to dementia in a relatively short period of time. The primary conclusions of the Task Force are that: (1) Parkinson's disease-mild cognitive impairment is common, (2) there is significant heterogeneity within Parkinson's disease-mild cognitive impairment in the number and types of cognitive domain impairments, (3) Parkinson's disease-mild cognitive impairment appears to place patients at risk of progressing to dementia, and (4) formal diagnostic criteria for Parkinson's disease-mild cognitive impairment are needed.

A recommended scale for cognitive screening in clinical trials of Parkinson's disease

Cognitive impairment is common in Parkinson's disease (PD). There is a critical need for a brief, standard cognitive screening measure for use in PD trials whose primary focus is not on cognition. The Parkinson Study Group (PSG) Cognitive/Psychiatric Working Group formed a Task Force to make recommendations for a cognitive scale that could screen for dementia and mild cognitive impairment in clinical trials of PD where cognition is not the primary outcome. This Task Force conducted a systematic literature search for cognitive assessments previously used in a PD population. Scales were then evaluated for their appropriateness to screen for cognitive deficits in clinical trials, including brief administration time (<15 minutes), assessment of the major cognitive domains, and potential to detect subtle cognitive impairment in PD. Five scales of global cognition met the predetermined screening criteria and were considered for review. Based on the Task Force's evaluation criteria the Montreal Cognitive Assessment (MoCA), appeared to be the most suitable measure. This Task Force recommends consideration of the MoCA as a minimum cognitive screening measure in clinical trials of PD where cognitive performance is not the primary outcome measure. The MoCA still requires further study of its diagnostic utility in PD populations but appears to be the most appropriate measure among the currently available brief cognitive assessments. Widespread adoption of a single instrument such as the MoCA in clinical trials can improve comparability between research studies on PD.

Utility of the NeuroTrax computerized battery for cognitive screening in Parkinson's disease: comparison with the MMSE and the MoCA

To determine the utility of a computerized assessment in Parkinson's disease (PD), we compared the cognitive performance of 50 PD patients on the NeuroTrax computerized battery relative to the mini-mental state examination (MMSE) and the Montreal Cognitive Assessment (MoCA). The results revealed fair agreement between impairment on the NeuroTrax and the MMSE (kappa=.291, p=.031) but only slight agreement between the NeuroTrax and the MoCA (kappa=.138, p = .054) and between the MoCA and the MMSE (kappa = .168, p = .069). The NeuroTrax identified 52% of the sample as average or above, 40% as below average, and 8% as impaired. The MoCA identified 54% of the sample as impaired (28% average or above and 18% below average), while the MMSE identified 66% as average or above (20% below average and 14% impaired). Several stepwise regressions revealed that executive and verbal functions were the best predictors of cognitive functioning on the NeuroTrax, while memory recall, serial sevens, naming, and abstraction were the best predictors on the MoCA. These results suggest that although the NeuroTrax may be useful in identifying executive cognitive deficits in PD, similar to the MMSE the NeuroTrax may lack optimal sensitivity. While the MoCA is sensitive, it may be too stringent in overclassifying PD patients as impaired.

Parkinson's disease dementia

Dementia associated with Parkinson's disease (PDD) is a common problem and one that is associated with significant morbidity and mortality. Over the past decade, increasing research efforts and funding have been directed toward an improved understanding of PDD. Despite these efforts, fundamental gaps remain in our knowledge. Consequently, therapeutic progress has been frustratingly slow and incomplete. To significantly affect PDD, novel "disease-modifying" agents, rather than more traditional neurotransmitter replacement approaches, likely will be required.

Using evidence-based medicine in neurology

Given the rising costs of health care, the rational use of resources is a necessity. Evidence-based medicine assists physicians in providing the right care to the right patient at the right time. Familiarity with scientific literature and clinical experience are also important in decision making. This article covers the basics of critical appraisal and an introduction to statistics that will help clinicians, patients, and policymakers make sense of scientific evidence.

The diagnostic accuracy of dementia-screening instruments with an administration time of 10 to 45 minutes for use in secondary care: a systematic review

Early screening for dementia is crucial for identifying reversible causes as well as managing, counseling, and other therapeutic interventions. Many reviews have compared the suitability of very brief screening instruments for use in primary care, but reviews on more extensive instruments in secondary care are scarce. In addition, results on diagnostic accuracy are often biased due to methodological shortcomings, differences in the spectrum of patients or reporting. This systematic review reports the diagnostic accuracy of dementia-screening instruments with an administration time of 10 to 45 minutes, validated in secondary care, restricted to mild dementia and validation studies of ''high quality.'' Characteristics such as cognitive domains and reliability figures are also highlighted.

Prion-like mechanisms in neurodegenerative diseases

Many non-infectious neurodegenerative diseases are associated with the accumulation of fibrillar proteins. These diseases all exhibit features that are reminiscent of those of prionopathies, including phenotypic diversity and the propagation of pathology. Furthermore, emerging studies of amyloid-beta, alpha-synuclein and tau--proteins implicated in common neurodegenerative diseases--suggest that they share key biophysical and biochemical characteristics with prions. Propagation of protein misfolding in these diseases may therefore occur through mechanisms similar to those that underlie prion pathogenesis. If this hypothesis is verified in vivo, it will suggest new therapeutic strategies to block propagation of protein misfolding throughout the brain.

Validity of the MoCA and MMSE in the detection of MCI and dementia in Parkinson disease

BACKGROUND

Due to the high prevalence of mild cognitive impairment (MCI) and dementia in Parkinson disease (PD), routine cognitive screening is important for the optimal management of patients with PD. The Montreal Cognitive Assessment (MoCA) is more sensitive than the commonly used Mini-Mental State Examination (MMSE) in detecting MCI and dementia in patients without PD, but its validity in PD has not been established.

METHODS

A representative sample of 132 patients with PD at 2 movement disorders centers was administered the MoCA, MMSE, and a neuropsychological battery with operationalized criteria for deficits. MCI and PD dementia (PDD) criteria were applied by an investigator blinded to the MoCA and MMSE results. The discriminant validity of the MoCA and MMSE as screening and diagnostic instruments was ascertained.

RESULTS

Approximately one third of the sample met diagnostic criteria for a cognitive disorder (12.9% PDD and 17.4% MCI). Mean (SD) MoCA and MMSE scores were 25.0 (3.8) and 28.1 (2.0). The overall discriminant validity for detection of any cognitive disorder was similar for the MoCA and the MMSE (receiver operating characteristic area under the curve [95% confidence interval]): MoCA (0.79 [0.72, 0.87]) and MMSE (0.76 [0.67, 0.85]), but as a screening instrument the MoCA (optimal cutoff point = 26/27, 64% correctly diagnosed, lack of ceiling effect) was superior to the MMSE (optimal cutoff point = 29/30, 54% correctly diagnosed, presence of ceiling effect).

CONCLUSIONS

The Montreal Cognitive Assessment, but not the Mini-Mental State Examination, has adequate psychometric properties as a screening instrument for the detection of mild cognitive impairment or dementia in Parkinson disease. However, a positive screen using either instrument requires additional assessment due to suboptimal specificity at the recommended screening cutoff point.

The morbid anatomy of dementia in Parkinson's disease

Dementia in Parkinson's disease (PD/PDD) is a common complication with a prevalence of up to 50%, but the specific changes underlying the cognitive decline remain undefined. Neuronal degeneration resulting in the dysfunction of multiple subcortical neurochemical projection systems has been described along with Lewy body-type pathology in cortical and limbic regions. Advanced alpha-synuclein (alphaSyn) pathology is not necessarily sufficient for producing dementia and concomitant Alzheimer's disease (AD) change has also been proposed as a possible substrate of PDD. A lack of consensus in the extant literature likely stems from clinical heterogeneity and variable reliability in clinical characterisation as well as other historical and methodological issues. The concurrent presence of abnormally deposited alphaSyn, amyloid-beta and tau proteins in the PDD brain and the interaction of these molecules in a linked pathological cascade of AD and PD-related mechanisms may prove important in determining the underlying pathological process for the development of dementia in PD and this concept of combined pathologies awaits further investigation.

Cognitive impairment in Parkinson's disease: tools for diagnosis and assessment

Cognitive impairment (CI) and dementia are frequent and debilitating features associated with Parkinson's disease (PD). Formal neuropsychological examination is required to ascertain the degree and pattern of CI over the course of the disease. The use of different tools may explain heterogeneous data obtained from studies to date. Normative data for extensively used scales [Mattis Dementia Rating Scale (MDRS), Mini-Mental State Examination (MMSE)] is incomplete in PD populations. According to sample characteristics, statistical analyses, and methodological quality, 33 studies using scales not specific to PD (MDRS, MMSE, Cambridge Cognitive Assessment, FAB) or PD-specific scales (Mini-Mental Parkinson, Scales for Outcomes of Parkinson's disease-Cognition, Parkinson's Disease-Cognitive Rating Scale, and Parkinson Neuropsychometric Dementia Assessment) were eligible for the critical analysis of their appropriateness to assess cognition in PD. Of the four scales specifically designed for PD, the SCOPA-COG and the PD-CRS have undergone extensive and rigorous validation processes. While the SCOPA-COG mainly assesses "frontal-subcortical" cognitive defects, the PD-CRS also assesses "instrumental-cortical" functions, allowing better characterization of the different patterns of CI that may be present in PD from the earliest stages. The MMP and PANDA scales were designed as brief screening tests for CI and have not yet been subjected to extensive clinimetric evaluations. Further research on PD-specific tools seems mandatory to help establish accurate cut-off scores for the diagnosis of mild PDD, detect cognitive profiles more prone to the future development of dementia, and allow comparisons between different descriptive or interventional studies.

Montreal cognitive assessment performance in patients with Parkinson's disease with "normal" global cognition according to mini-mental state examination score

OBJECTIVES

To examine Montreal Cognitive Assessment (MoCA) performance in patients with Parkinson's disease (PD) with "normal" global cognition according to Mini-Mental State Examination (MMSE) score.

DESIGN

A cross-sectional comparison of the MoCA and the MMSE.

SETTING

Two movement disorders centers at the University of Pennsylvania and the Philadelphia Veterans Affairs Medical Center.

PARTICIPANTS

A convenience sample of 131 patients with idiopathic PD who were screened for cognitive and psychiatric complications.

MEASUREMENTS

Subjects were administered the MoCA and MMSE, and only subjects defined as having a normal age- and education-adjusted MMSE score were included in the analyses (N=100). As previously recommended in patients without PD, a MoCA score less than 26 was used to indicate the presence of at least mild cognitive impairment (MCI).

RESULTS

Mean MMSE and MoCA scores+/-standard deviation were 28.8+/-1.1 and 24.9+/-3.1, respectively. More than half (52.0%) of subjects with normal MMSE scores had cognitive impairment according to their MoCA score. Impairments were seen in numerous cognitive domains, including memory, visuospatial and executive abilities, attention, and language. Predictors of cognitive impairment on the MoCA using univariate analyses were male sex, older age, lower educational level, and greater disease severity; older age was the only predictor in a multivariate model.

CONCLUSION

Approximately half of patients with PD with a normal MMSE score have cognitive impairment based on the recommended MoCA cutoff score. These results suggest that MCI is common in PD and that the MoCA is a more sensitive instrument than the MMSE for its detection.

Addenbrooke's Cognitive Examination validation in Parkinson's disease

BACKGROUND

There is a clear need for brief, sensitive and specific cognitive screening instruments in Parkinson's disease (PD).

OBJECTIVES

To study Addenbrooke's Cognitive Examination (ACE) validity for cognitive assessment of PD patient's using the Mattis Dementia Rating Scale (MDRS) as reference method. A specific scale for cognitive evaluation in PD, in this instance the Scales for Outcomes of Parkinson's disease-Cognition (SCOPA-COG), as well as a general use scale the Mini-mental state examination (MMSE) were also studied for further correlation.

METHODS

Forty-four PD patients were studied, of these 27 were males (61%), with a mean (SD) age of 69.5 (11.8) years, mean (SD) disease duration of 7.6 (6.4) years (range 1-25), mean (SD) total Unified Parkinson's Disease Rating Scale (UPDRS) score 37 (24) points, UPDRS III 16.5 (11.3) points. MDRS, ACE and SCOPA-COG scales were administered in random order. All patients remained in on-state during the study.

RESULTS

Addenbrooke's Cognitive Examination correlated with SCOPA-COG (r = 0.93, P < 0.0001), and MDRS (r = 0.91 P < 0.0001) and also with MMSE (r = 0.84, P < 0.001). Area under the receiver-operating curve, taking MDRS as the reference test, was 0.97 [95% confidence interval (CI): 0.92-1.00] for ACE, 0.92 (95% CI: 0.83-1.00) for SCOPA-COG and 0.91 (95% CI: 0.83-1.00) for MMSE. Best cut-off value for ACE was 83 points [Sensitivity (Se) = 92%; Specificity (Sp) = 91%; Kappa concordance (K) = 0.79], 20 points for the SCOPA-COG (Se = 92%; Sp = 87%; K = 0.74) and 26 points for MMSE (Se = 61%; Sp = 100%; K = 0.69).

CONCLUSION

Addenbrooke's Cognitive Examination appears to be a valid tool for dementia evaluation in PD, with a cut-off point which should probably be set at 83 points, displaying good correlation with both the scale specifically designed for cognitive deficits in PD namely SCOPA-COG, as well as with less specific tests such as MMSE.

CAMcog as a screening tool for diagnosis of mild cognitive impairment and dementia in a Brazilian clinical sample of moderate to high education

BACKGROUND

The CAMCOG is a brief neuropsychological battery designed to assess global cognitive function and ascertain the impairments that are required for the diagnosis of dementia. To date, the cut-off scores for mild cognitive impairment (MCI) have not been determined. Given the need for an earlier diagnosis of mild dementia, new cut-off values are also necessary, taking into account cultural and educational effects.

METHODS

One hundred and fifty-seven older adults (mean age: 69.6 +/- 7.4 years) with 8 or more years of formal education (mean years of schooling 14.2 +/- 3.8) attending a memory clinic at the Institute of Psychiatry University of Sao Paulo were included. Subjects were divided into three groups according to their cognitive status, established through clinical and neuropsychological assessment: normal controls, n = 62; MCI, n = 65; and mild or moderate dementia, n = 30. ROC curve analyses were performed for dementia vs controls, MCI vs controls and MCI vs dementia.

RESULTS

The cut-off values were: 92/93 for dementia vs controls (AUC = 0.99: sensitivity: 100%, specificity: 95%); 95/96 for MCI vs controls (AUC = 0.83, sensitivity: 64%, specificity: 88%), and 85/86 for MCI vs dementia (AUC = 0.91, sensitivity: 81%, specificity: 88%). The total CAMCOG score was more accurate than its subtests Mini-mental State Examination, Verbal Fluency Test and Clock Drawing Test when used separately.

CONCLUSIONS

The CAMCOG discriminated controls and MCI from demented patients, but was less accurate to discriminate MCI from controls. The best cut-off value to differentiate controls and demented was higher than suggested in the original publication, probably because only cases of mild to moderate dementia were included. This is important given the need for a diagnostic at earlier stages of Alzheimer's disease.

Dementia and functional decline in patients with Parkinson's disease

Functional decline in Parkinson's disease (PD), characterized by reduced ability to carry out activities of daily living, usually results from typical motor impairment and may be aggravated by concomitant cognitive impairment.

Objective

To compare the functional decline in Parkinson's disease between patients with dementia and cognitively preserved patients.

Methods

From an original sample composed of 50 patients with a clinical diagnosis of idiopathic PD seen in a consecutive series, 33 non-depressed patients were selected comprising 13 with dementia and 20 cognitively preserved individuals. All patients enrolled in this study were drawn from a public outpatient clinic, specialized in movement disorders. The clinical stage of PD was determined by the Hoehn & Yahr scale, and the functional capacity was verified using the Unified Parkinson's Disease Rating Scale UPDRS ADL (subscale II: activities of daily living) and the Schwab & England scale. The two last scales measure the functional degree of independence in activities of daily living. The neuropsychological assessment was performed using The Cambridge Examination for Mental Disorders of the Elderly - CAMCOG, Cognitive Section and the Stroop Color Word Test.

Results

As expected, in comparison with cognitively preserved patients, the group with dementia presented significantly lower scores throughout the neuropsychological evaluation. The patients with dementia were found to have a longer period of disease, a more advanced clinical staging according to the Hoehn & Yahr, and greater functional decline according both to the UPDRS ADL and Schwab & England, with statistically significant difference between the groups.

Conclusion

Patients with dementia were at a more advanced clinical stage of Parkinson's disease and evidenced greater functional decline in comparison with patients without dementia.

Everyday cognitive failures and memory problems in Parkinson's patients without dementia

There is growing evidence that Parkinson's disease patients without dementia exhibit cognitive deficits in some executive, memory and selective attention tasks. However, the impact of these deficits on their everyday cognitive functioning remains largely unknown. This issue was explored using self-report questionnaires. Twenty-four Parkinson's patients and 24 age-matched controls rated how frequently they make particular cognitive errors, such as forgetting what they were about to say. In addition, a partner or significant other also rated each participant's propensity for making cognitive errors. Rather than simply rating themselves as making more of all types of errors, these results indicate that PD patients make more of specific types of error. Further analysis suggests that some of these errors are related to attentional processes (being more distractible) whereas others are related to retrieval processes (being unable to recall important details from the previous day).

Increased cortico-cortical functional connectivity in early-stage Parkinson's disease: an MEG study

We set out to determine whether changes in resting-state cortico-cortical functional connectivity are a feature of early-stage Parkinson's disease (PD), explore how functional coupling might evolve over the course of the disease and establish its relationship with clinical deficits. Whole-head magnetoencephalography was performed in an eyes-closed resting-state condition in 70 PD patients with varying disease duration (including 18 recently diagnosed, drug-naive patients) in an "OFF" medication state and 21 controls. Neuropsychological testing was performed in all subjects. Data analysis involved calculation of three synchronization likelihood (SL, a general measure of linear and non-linear temporal correlations between time series) measures which reflect functional connectivity within (local) and between (intrahemispheric and interhemispheric) ten major cortical regions in five frequency bands. Recently diagnosed, drug-naive patients showed an overall increase in alpha1 SL relative to controls. Cross-sectional analysis in all patients revealed that disease duration was positively associated with alpha2 and beta SL measures, while severity of parkinsonism was positively associated with theta and beta SL measures. Moderately advanced patients had increases in theta, alpha1, alpha2 and beta SL, particularly with regard to local SL. In recently diagnosed patients, cognitive perseveration was associated with increased interhemispheric alpha1 SL. Increased resting-state cortico-cortical functional connectivity in the 8-10 Hz alpha range is a feature of PD from the earliest clinical stages onward. With disease progression, neighboring frequency bands become increasingly involved. These findings suggest that changes in functional coupling over the course of PD may be linked to the topographical progression of pathology over the brain.

Resistance training with creatine monohydrate improves upper-body strength in patients with Parkinson disease: a randomized trial

BACKGROUND

Persons with Parkinson disease (PD) exhibit decreased muscular fitness including decreased muscle mass, muscle strength, bioenergetic capabilities and increased fatigability.

OBJECTIVE

This purpose of this investigation was to evaluate the therapeutic effects of resistance training with and without creatine supplementation in patients with mild to moderate PD.

METHODS

Twenty patients with idiopathic PD were randomized to receive creatine monohydrate supplementation plus resistance training (CRE) or placebo (lactose monohydrate) plus resistance training (PLA), using a double-blind procedure. Creatine and placebo supplementation consisted of 20 g/d for the first 5 days and 5 g/d thereafter. Both groups participated in progressive resistance training (24 sessions, 2 times per week, 1 set of 8-12 repetitions, 9 exercises). Participants performed 1-repetition maximum (1-RM) for chest press, leg extension, and biceps curl. Muscular endurance was evaluated for chest press and leg extension as the number of repetitions to failure using 60% of baseline 1-RM. Functional performance was evaluated as the time to perform 3 consecutive chair rises.

RESULTS

Statistical analyses (ANOVA) revealed significant Group x Time interactions for chest press strength and biceps curl strength, and post hoc testing revealed that the improvement was significantly greater for CRE. Chair rise performance significantly improved only for CRE (12%, P=.03). Both PLA and CRE significantly improved 1-RM for leg extension (PLA: 16%; CRE: 18%). Muscular endurance improved significantly for both groups.

CONCLUSIONS

These findings demonstrate that creatine supplementation can enhance the benefits of resistance training in patients with PD.

The sensitivity and specificity of the Middlesex Elderly Assessment of Mental State (MEAMS) for detecting cognitive impairment after stroke

The aim of the study was to assess the sensitivity and specificity of the MEAMS (Golding, 1989) for detecting cognitive impairment after stroke. Stroke patients admitted to hospital received a cognitive screening assessment, the MEAMS, and a detailed cognitive assessment. The information obtained from the detailed assessment was summarised in a structured written report. From the conclusions in these reports, patients were classified as "impaired" or "not impaired" in perception, memory, executive function and language. The sensitivity and specificity of the MEAMS subtests and the overall number of tests passed were determined in relation to the presence of impairment, as given in the overall conclusion of the written reports. There were 30 stroke patients, aged 58 to 92 (mean 75.80, SD 7.94) years. Of these, 17 were men and 13 were women. The sensitivity of the MEAMS subtests ranged from 11% to 100% and the specificity ranged from 69% to 100%. The sensitivity of the overall MEAMS score was 52% and the specificity was 100%, using a cut-off score of 3 or more fails to indicate impairment. Three subtests, Orientation, Naming and Unusual views had 81% sensitivity and 50% specificity for detecting problems in language, perception or memory. The MEAMS was not a sensitive screen for overall cognitive impairment or for memory, perceptual, language, or executive function problems after stroke, but it was specific. Although screening for cognitive impairment is important, the MEAMS is not recommended as the sole method, as it produces an unacceptably high false negative rate. Three subtests (Orientation, Naming and Unusual views) had 81% sensitivity and 50% specificity for detecting cognitive problems in language, perception or memory after stroke.

Differential attrition in a caregiver skill training trial

Participant attrition in randomized trials can reduce statistical power and bias outcomes. However, elective withdrawals are seldom discussed in trial reports. We examined factors associated with elective withdrawals for the first 131 Alzheimer's disease (AD) and Parkinson's disease (PD) caregiver participants that entered Project ASSIST (Assistance, Support and Self-health Initiated through Skill Training), an on-going trial of caregiver skill training interventions. After 20 months of recruitment, 14 (11%) of the 131 ASSIST participants had electively withdrawn before completing the final assessment. Survival analysis demonstrated AD caregivers and non-spousal caregivers dropped out earlier than PD and spousal caregivers, even after controlling for selected baseline covariates. Findings suggest caregiver trial contact strategies may need to be tailored to retain different caregiver groups.

Demonstration of cognitive decline in Parkinson's disease using the Cambridge Cognitive Assessment (Revised) (CAMCOG-R)

BACKGROUND

Cognitive impairment is well recognised in Parkinson's Disease (PD) but few studies have examined cognitive decline over time in such subjects. Standard clinical assessments of cognitive function, such as the MMSE, do not measure all cognitive domains and often have a ceiling effect. CAMCOG-R provides a more comprehensive cognitive assessment allowing several different domains of cognition to be compared. It also features the ability to test 'executive function'. CAMCOG-R has only been reported on one previous occasion in PD subjects and this is the first study to report a follow-up CAMCOG-R to assess cognitive decline.

METHODS

In a previously published study CAMCOG-R was administered to a prevalent community-based population of 94 subjects with PD with a MMSE of 25 or above. In this subsequent study 85 of the subjects (two declined and seven were deceased) underwent a follow-up CAMCOG-R after a mean delay of 13.1 months.

RESULTS

The initial, and follow-up mean total CAMCOG-R scores were 88.65/104 and 84.75/104 respectively, demonstrating a significant decline (p < 0.05). Significant cognitive decline (p < 0.05) was also seen across every CAMCOG-R cognitive domain and in the executive function scores.

CONCLUSIONS

A wide range of cognitive ability was again demonstrated using CAMCOG-R in this PD population. The decline of 3.9 CAMCOG-R points over the 13-month period compares to other previous studies showing an annual decline of 1.6 CAMCOG points in normal elderly individuals and 12 CAMCOG points annually in those with established dementia. This study suggests that CAMCOG-R is a useful and appropriate tool for use in follow-up cognitive screening in PD subjects.

Cognitive deficits and psychosis in Parkinson's disease: a review of pathophysiology and therapeutic options

Parkinson's disease is a neurodegenerative disorder causing not only motor dysfunction but also cognitive, psychiatric, autonomic and sensory disturbances. Symptoms of dementia and psychosis are common: longitudinal studies suggest that up to 75% of patients with Parkinson's disease may eventually develop dementia, and the prevalence of hallucinations ranges from 16-17% in population-based surveys to 30-40% in hospital-based series. These cognitive and behavioural features are important in terms of prognosis, nursing home placement and mortality. The pattern of cognitive deficits in Parkinson's disease is variable, but often includes executive impairment similar to that seen in patients with frontal lesions, as well as episodic memory impairment, visuospatial dysfunction and impaired verbal fluency. The most common manifestation of psychosis in Parkinson's disease is visual hallucinations, but delusions, paranoid beliefs, agitation and florid psychosis can also occur. An understanding of the pathophysiology underlying these symptoms is essential to the development of targeted therapeutic strategies. Post-mortem studies suggest an association between Lewy body deposition and dementia in Parkinson's disease, and indeed Parkinson's disease and dementia with Lewy bodies may form part of the same disease spectrum. Whether Lewy bodies actually play a causative role in cognitive dysfunction, however, is unknown. Deficits in neurotransmitter systems provide more obvious therapeutic targets and dysfunction of dopaminergic, cholinergic, noradrenergic and serotonergic systems have all been implicated; these may each underlie different features of Parkinson's disease dementia, perhaps explaining some of the heterogeneity of the syndrome. Psychosis has traditionally been considered as a dopaminergic drug-induced phenomenon, but factors intrinsic to the disease process itself also cause hallucinations and delusions. These factors may include Lewy body deposition in the limbic system, cholinergic deficits and impairments of primary visual processing. Therapeutic intervention for cognitive and behavioural symptoms in Parkinson's disease currently focuses on two main groups of drugs: cholinesterase inhibitors and atypical antipsychotics. A recent large, randomised, controlled trial suggests that cholinesterase inhibitors can produce a modest improvement in cognitive function, as well as psychotic symptoms, generally without an adverse effect on motor function. Certain atypical antipsychotics allow hallucinations, delusions and behavioural problems to be brought under control with minimal deleterious effects on motor function and cognition, but their safety in elderly patients has recently been called into question. Deep brain stimulation does not appear to be a useful treatment for cognitive and psychiatric dysfunction in patients with Parkinson's disease. Modafinil improves alertness in Parkinson's disease and warrants further investigation to establish its effects on cognitive performance.

Phenomenology and management of cognitive and behavioral disorders in Parkinson's disease. Rise and logic of dementia in Parkinson's disease

An overview of studies on the issue of dementia in Parkinson's disease shows that, over time, there has been an evolution in the perception of the magnitude of the problem and of its nature. Dementia seems today to be part of the disease. This change in the understanding of the disease can be accounted for by various methodological problems and by difficulties, on one hand, in the definition of dementia and its differentiation from other conditions, and, on the other hand, in the diagnosis of the disease itself in individual cases. Optimal therapeutic strategies are also examined, either based on cholinesterase inhibitors or antiparkinsonian drugs and symptomatic measures.

Motor subtype and cognitive decline in Parkinson's disease, Parkinson's disease with dementia, and dementia with Lewy bodies

BACKGROUND

A previous cross sectional study found over-representation of a postural instability gait difficulty (PIGD) motor subtype in Parkinson's disease patients with dementia (PDD) and dementia with Lewy bodies (DLB), compared with Parkinson's disease (PD).

AIMS

(1) To examine rates of cognitive and motor decline over two years in PD (n=40), PDD (n=42) and DLB (n=41) subjects, compared with age matched controls (n=41), (2) to record whether motor phenotypes of PD, PDD, and DLB subjects changed during the study, (3) to find out if cognitive and motor decline in PD was associated with baseline motor subtype, and (4) to report the incidence of dementia in PD patients in relation to baseline motor subtype.

RESULTS

Most of PDD and DLB participants were PIGD subtype at baseline assessment. In the non-demented PD group, tremor dominant (TD) and PIGD subtypes were more evenly represented. Cognitive decline over two years was greater in PDD and DLB groups (mean decline in MMSE -4.5 and -3.9, respectively), compared with PD (-0.2) and controls (-0.3). There was an association between PIGD subtype and increased rate of cognitive decline within the PD group. Of 40 PD patients, 25% of the 16 PIGD subtype developed dementia over two years, compared with none of the 18 TD or six indeterminate phenotype cases (chi2=6.7, Fisher's exact test p<0.05).

CONCLUSION

A PIGD motor subtype is associated with a faster rate of cognitive decline in PD and may be considered a risk factor for incident dementia in PD.

Medicine-taking behavior: implications of suboptimal compliance in Parkinson's disease

Management of Parkinson's disease (PD) depends primarily on oral medication. There are several drug classes and multiple doses and formulations, which make optimizing therapy complex. Variable drug absorption and the short half-life of most antiparkinson treatments, especially levodopa, are a main focus in understanding complications and have encouraged alternative delivery systems to limit fluctuation and dyskinesia at later stages. Comparatively little attention is paid to the way patients take their oral medication. Variable medicine-taking behavior can affect the clinician's understanding of the diagnosis and rate of progression, and further prescription of PD medication. Medicine overuse in later stage PD is well documented and causes psychiatric disturbance and increases motor complications, but evidence of undertreatment and erratic intake is emerging, which is likely to affect motor control and quality of life adversely. Methods of quantifying compliance are compared for accuracy and limitations. Understanding medicine-taking behavior is a first step in optimizing therapy and requires consideration of a patient's personal beliefs about their medicines. Although the benefits of regularizing oral medicine-taking in a practical, achievable way in PD remain untested, such an approach might prolong and smooth the benefits of oral medication and is worthy of further research.

Deep brain stimulation: Preoperative issues

Numerous factors need to be taken into account in deciding whether a patient with Parkinson's disease (PD) is a candidate for deep brain stimulation. Patient-related personal factors including age and the presence of other comorbid disorders need to be considered. Neuropsychological and neuropsychiatric concerns relate both to the presurgical status of the patient and to the potential for surgery to result in new problems postoperatively. A number of factors related to the underlying PD need to be considered, including the specific parkinsonian motor indications (e.g., tremor, bradykinesia, gait dysfunction), previous medical therapies, including benefit from current therapy and adverse effects, and past surgical treatments. Definable causes of Parkinsonism, particularly atypical Parkinsonisms, should be considered. Finally, methods of evaluating outcomes should be defined and formalized. This is a report from the Consensus on Deep Brain Stimulation for Parkinson's Disease, a project commissioned by the Congress of Neurological Surgeons and the Movement Disorder Society (MDS). The report has been endorsed by the Scientific Issues Committee of the MDS and the American Society of Stereotactic and Functional Neurosurgery. It outlines answers to a series of questions developed to address all aspects of deep brain stimulation preoperative decision-making.

Management of Parkinson???s Disease Dementia

Parkinson's disease dementia (PDD) ultimately develops in about 80% of patients with Parkinson's disease (PD), and cross-sectional studies have found that some 30% of these patients will experience neuropsychiatric symptoms, such as visual hallucinations and psychosis. The most consistently reported risk factors for dementia in PD are age, severe parkinsonism and mild cognitive impairment. In PDD, both subcortical cognitive and cortical cognitive profiles are described. Specific disorders of sleep, such as rapid eye movement sleep behaviour disorder, excessive daytime sleepiness and sleep attacks, occur frequently. Alzheimer and Lewy body pathology coexist, but the Lewy body pathology in limbic and cortical areas seems to be the main cause of dementia. Neurochemical changes in the biogenic amines and acetylcholine are common, and magnetic resonance imaging studies have shown cortical atrophy in wide cortical areas, including the hippocampus. All PD patients should be screened for mild cognitive impairment and dementia. A large randomised clinical trial showed that the cholinesterase inhibitor rivastigmine has desirable effects on cognition and neuropsychiatric symptoms in PDD patients. Atypical antipsychotic agents may improve psychosis in PDD, but the evidence for this is poor and adverse effects from such therapy are common and may be severe. Non-pharmacological interventions can also be effective but require further study.

Caring for family with Alzheimer's disease and Parkinson's disease: needs, challenges and satisfaction

A convenience sample of 40 family members caring for an individual with either Alzheimer's disease (AD) or Parkinson's disease (PD) completed the Caregiver Assistance Measure (CAM) to identify the types of assistance that would be most helpful in caring for a family member at home. The CAM measures three categories or types of assistance: care knowledge and skills, self-care, and resource acquisition. Caregivers also completed open-ended questions about the difficulties and the satisfactions of caregiving. The PD and AD caregivers agreed on the importance of 75% of the assistance items on the CAM. In addition, both groups of caregivers identified issues related to care knowledge and skills and selfcare as the most difficult aspects of caregiving. These findings suggest many caregiver needs may be common across chronic illness populations and provide initial support for the development and testing of standardized interventions for caregivers.

Clinical and genetic study of a large SPG4 Italian family

A novel SPG4 906delT frame-shift mutation in exon 6 was identified in a large Italian family with an autosomal dominant form of hereditary spastic paraplegia (ADHSP). Intrafamilial phenotypic variations observed in the pedigree included spasticity and additional clinical features, such as peripheral sensory-motor neuropathy, cognitive impairment, and urological dysfunction. Severe clinical features were found predominantly in the men who were affected, and there was no statistically significant correlation of disability and time since onset of symptoms, suggesting the existence of other genetic/nongenetic modifier(s), including gender.

Risk and incidence of dementia in a cohort of older subjects with Parkinson's disease in the United Kingdom

To determine the incidence and possible risk factors for dementia in patients with clinically probable Parkinson's disease (PD), a cohort (n = 86) of nondemented patients over 65 years of age with PD fulfilling the PD Brain Bank clinical diagnostic criteria were determined from community records. A similarly aged group of control subjects (n = 102) were recruited from the same area. Both groups were assessed at baseline and approximately 4 years later for cognition, mood, and motor function (PD patients only). The presence and severity of cognitive impairments was based on subject and informant interview, neuropsychological assessment based on the Cambridge Cognitive Examination (CAMCOG) and the application of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV). At 4 years, 51 (59%) of the PD and 72 (71%) of the control cohort were available for reassessment. Of the PD cohort, 18 (35.3%) had developed dementia and 5 (9.4%) had evidence of mild cognitive impairments. In the control group, 5 (7%) had developed dementia. The incidence of dementia per 1,000 person-years in the PD cohort was 107.1 (95% confidence interval [CI], 59.9-159.8) and in the control group was 17.9 (95% CI, 5.8-31.9). The relative risk of patients developing dementia was 5.1 times that of the controls (95% CI, 2.1-12.5). Increasing age, later age of onset of PD, longer duration of PD symptoms, the presence of hallucinations, and impairment of memory and language function were all predictive factors for the development of dementia (P < 0.05). Dementia was also found to be a significant predictor for institutional placement in the PD group. Compared with similarly aged controls, patients with clinically probable PD have a fivefold-increased risk of developing dementia. This finding has significant implications for successful clinical management of this condition.

Sydney multicenter study of Parkinson's disease: Non‐ L ‐dopa–responsive problems dominate at 15 years

One-third of the 149 people recruited 15 to 18 years ago in the Sydney Multicenter Study of Parkinson's disease have survived. The original study compared low-dose levodopa with low-dose bromocriptine. We now report the problems experienced by people who survive 15 years from diagnosis. The standardized mortality ratio is significantly elevated at 1.86 and is not significantly different between treatment arms. Falls occur in 81% of patients, and 23% sustained fractures. Cognitive decline is present in 84%, and 48% fulfill the criteria for dementia. Hallucinations and depression are experienced by 50%. Choking has occurred in 50%, symptomatic postural hypotension in 35%, and urinary incontinence in 41%. No patient is still employed, and 40% of patients live in aged care facilities. Although approximately 95% have experienced L-dopa-induced dyskinesia/dystonia and end of dose failure of medication, in the majority, these symptoms are not disabling. Dyskinesia and dystonia were delayed by early use of bromocriptine, but end-of-dose failure appeared at a similar time once L-dopa was added. The rate of disease progression is similar in both arms of the study. We conclude that the most disabling long-term problems of Parkinson's disease relate to the emergence of symptoms that are not improved by L-dopa. Neuroprotective interventions in Parkinson's disease should be judged by their ability to improve non-L-dopa-responsive aspects of the disease, rather than just by their capacity to delay the introduction of L-dopa or reduce its associated side effects.

What causes mental dysfunction in Parkinson's disease?

Parkinson's disease (PD) is frequently associated with mental dysfunction. Domain-specific cognitive deficits are ubiquitous, and although they may not be clinically apparent in all patients, they are demonstrable by neuropsychological testing. Dementia is less frequent but is present significantly more in PD patients than in controls, with a cumulative prevalence rate up to 40% and up to six-fold increased incidence. Cognitive impairment mainly involves executive and visuospatial functions; memory is secondarily impaired with relatively preserved recognition. Qualitatively, the neuropsychological profile of dementia encompasses the same type of deficits found in nondemented PD patients. The dementia seen in PD, therefore, can be described as a dysexecutive syndrome combined with visuospatial dysfunction and behavioural symptoms. Dopaminergic, noradrenergic, serotoninergic, and cholinergic deficits have all been described as the underlying neurochemical impairment, but the strongest evidence exists for a cholinergic dysfunction. Involvement of brainstem nuclei, limbic structures, and cerebral cortex have been suggested as the site, and Lewy body (LB) degeneration and Alzheimer-type changes as the type of pathology underlying the mental dysfunction in PD. Although there is still some controversy as to the site and type of pathology, recent evidence suggests that LB-type degeneration in limbic structures and cerebral cortex, with consequent synaptic and cell loss, is the main pathological state associated with dementia in PD.

The cognitive ability of an incident cohort of Parkinson's patients in the UK. The CamPaIGN study

We have used multiple sources to identify a population-representative cohort of newly diagnosed patients with parkinsonism and Parkinson's disease in the UK over a 2-year period. All patients have been invited to participate in a detailed clinical assessment either at home or in an outpatient clinic. These assessments have been used to refine clinical diagnoses of parkinsonism using established criteria, and describe some of the phenotypic variability of Parkinson's disease at the time of diagnosis. The crude incidence of Parkinson's disease was 13.6/10(5yr-1) [confidence interval (CI) 11.8-15.6 and of parkinsonism was 20.9/10(5yr-1) (CI 18.7-23.3). Age-standardized to the 1991 European population, the incidence figures become 10.8/10(5yr-1) (CI 9.4-12.4) for Parkinson's disease and 16.6/10(5yr-1) (CI 14.8-18.6) for parkinsonism. Thirty-six per cent of the Parkinson's disease patients had evidence of cognitive impairment based on their performance in the Mini-Mental State Examination, a pattern recognition task, and the Tower of London task. The pattern of cognitive deficits seen among these patients using these and further cognitive tasks suggests that sub-groups of patients based on cognitive ability might be identifiable even in the early stages of disease, which may reflect regional differences in the underlying neuropathological processes.

Stability and change in patterns of coping with Parkinson's disease

This study examined how Parkinson's disease patients cope with disease-related stressors over time. Of interest was whether patterns of coping would support a dispositional model of coping (i.e., stability) or a contextual model of coping (i.e., change). The influence of stability and change in coping on mental and physical health outcomes was also examined. As expected, results showed that as the disease progressed, severity and distress increased and quality of life decreased. There was no change overall in the symptoms perceived as most stressful or the coping strategies employed to manage them. However, stability within individuals was associated with poorer mental and physical outcomes, whereas change in coping strategies was associated with more optimal outcomes. Evidence supporting both models of coping was found, and the potential applications of these findings for psychosocial intervention are discussed.