Cognitive function assessment in idiopathic Parkinson's disease

Cognitive profile of patients with and without speech impairment in Parkinson's disease

Cognitive functions have been the subject of studies evaluating the pathophysiological mechanism of speech control.

Objective

To compare the groups of patients with and without speech disorders with cognitive assessment, demographic, and clinical data (disease duration, functionality, and motor symptoms).

Methods

Retrospective, cross-sectional study. Patients were evaluated using the Addenbrooke's Cognitive Examination III and neuropsychological tests. The following speech subsystems were analyzed: articulation, phonation, resonance, and prosody, through auditory-perceptual evaluation (based on the Protocol for the Evaluation of Acquired Speech Disorders in Individuals with Parkinson's Disease - PADAF Protocol tests), observing aspects of speech programming and execution. The patients were distributed into three subgroups (normal cognition, mild cognitive impairment, and dementia). After speech evaluation, they were divided into two subgroups (with and without speech disorders).

Results

A total of 150 patients participated in this study, 104 men and 46 women, 63.58 (8.81) years of age, 11.03 (4.00) years of schooling, 6.61 (4.69) years of disease progression, and with the highest proportion of individuals in stage I-II of the Hoehn & Yarh (H&Y) scale (86, or 57.33%). Statistically significant differences were observed between subgroups with and without speech alteration. Worse performance was verified in the Trail Making Test (TMT) TMT-Δ and a tendency of difference in the TMT-B of the subgroup with speech disorders, in addition to worse severity of motor symptoms (H&Y) and cognitive complaints.

Conclusion

Individuals with speech disorders brought more frequent cognitive complaints and impairment below expected in tests assessing executive functions. Future studies, with stratification by type of speech disorder, are necessary to contribute to and validate these results.

Cognitive Function and Postural Control Strategies in Relation to Disease Progression in Patients with Parkinson's Disease

AIM

This study assessed the influence of performing an additional cognitive task on center of pressure (COP) displacement in the early and advanced stages of patients with Parkinson's disease (PD) compared to age-matched healthy controls (HCs).

METHODS

The study included 40 HCs and 62 patients with PD: early PD (n = 38) and advanced PD (n = 24). COP parameters were determined by static posturography during quiet standing with open eyes (ST, single task) and simultaneous performance of a cognitive task (DT, dual task). Cognitive functioning was examined with a Mini Mental State Examination, number-counting-backward test, and number of enunciated words during DT.

RESULTS

In the advanced-PD group, DT significantly reduced the sway radius (p = 0.009), area of stabilogram (p = 0.034), medio-lateral length (p = 0.027), and velocity (p = 0.033) compared to ST. In HCs, DT showed a significant increase in the sway radius (p = 0.006), total length (p = 0.039), sway velocity (p = 0.037), anterior-posterior length, and sway velocity. Both PD groups showed worse cognitive performance compared to HCs.

CONCLUSIONS

Both early and advanced patients with PD showed significant delay in cognitive performance associated with executive function compared to the HCs. During additional cognitive tasks, patients with advanced stages of PD may reduce stabilographic parameters in medio-lateral direction, and this is probably an adaptive strategy to restore balance.

Screening for cognitive dysfunction in Huntington's disease with the clock drawing test

BACKGROUND

The aim of the study is to investigate the performance of the clock drawing test as a screening tool for cognitive impairment in Huntington's disease (HD) mutation carriers.

METHODS

The performance of the clock drawing test was assessed in 65 mutation carriers using the Shulman and the Freund scoring systems. The mini-mental state examination, the Symbol Digit Modalities Test, the Verbal Fluency Test, and the Stroop tests were used as comparisons for the evaluation of cognitive functioning. Correlations of the clock drawing test with various cognitive tests (convergent validity), neuropsychiatric characteristics (divergent validity) and clinical characteristics were analysed using the Spearman's rank correlation coefficient. Receiver-operator characteristic analyses were performed for the clock drawing test against both the mini-mental state examination and against a composite variable for executive cognitive functioning to assess optimal cut-off scores.

RESULTS

Inter-rater reliability was high for both the Shulman and Freund scoring systems (ICC = 0.95 and ICC = 0.90 respectively). The clock drawing tests showed moderate to high correlations with the composite variable for executive cognitive functioning (mean ρ = 0.75) and weaker correlations with the mini-mental state examination (mean ρ = 0.62). Mean sensitivity of the clock drawing tests was 0.82 and mean specificity was 0.79, whereas the mean positive predictive value was 0.66 and the mean negative predictive value was 0.87.

CONCLUSION

The clock drawing test is a suitable screening instrument for cognitive dysfunction in HD, because it was shown to be accurate, particularly so with respect to executive cognitive functioning, and is easy and quick to use. Copyright © 2016 John Wiley & Sons, Ltd.

Multiple clock drawing scoring systems: simpler is better

OBJECTIVE

The clock drawing test (CDT) is a widely used cognitive screening tool that has been well accepted among clinicians and patients for its ease of use and short administration time. Although there is ample interest in the CDT as a screening instrument, there remains a range of CDT administration and scoring systems with no consensus on which system produces the most valid results while remaining user friendly. The aims of this review are to synthesize the available evidence on CDT scoring systems' effectiveness and to recommend which system is best suited for use at the clinical frontlines.

DESIGN

A Pubmed literature search was carried out from 2000 to 2013 including manual cross-referencing of bibliographies in order to capture studies published after Shulman's comprehensive review published in 2000. A brief summary of all original scoring systems is included, as well as a review of relevant comparative studies.

RESULTS

The consensus from multiple comparison studies suggests that increasing the complexity of CDT scoring systems does little to enhance the test's ability to identify significant cognitive impairment. Moreover, increased complexity in scoring adds to the administration time, thereby reducing the test's utility in clinical settings.

CONCLUSIONS

In comparing scoring systems, no system emerged as consistently superior in terms of predictive validity. The authors conclude that when scoring the CDT as a screening instrument in a primary/general medicine/community setting, simpler is better, and perhaps qualitative assessment of "normal" versus "abnormal" may be sufficient for screening purposes and the establishment of a baseline for follow-up.

Muscle strength and executive function as complementary parameters for the assessment of impairment in Parkinson's disease

OBJECTIVE

To evaluate the relationship between the quantitative results of functional and cognitive performance of patients with Parkinson's disease (PD) and disease severity; and to study the relationship between patients' functional and cognitive capacity and motor impairment (Unified Parkinson's Disease Rating Scale - UPDRS III).

METHOD

Twenty-nine subjects clinically diagnosed with PD were classified into three groups according to disease severity using the modified Hoehn and Yahr Scale (H&Y). They were submitted to functional (Senior Fitness Test) and neuropsychological tests. Stepwise regression analysis showed a significant association between H&Y and upper limb strength (r² =0.30; p=0.005) and executive function (r² =0.37; p=0.004). In relation to UPDRS III, there was a significant association between lower limb strength (r² =0.27; p=0.010) and global cognitive status (r² =0.24; p=0.024).

CONCLUSION

The implementation of simple tests of functional capacity associated with neuropsychological testing can help to assess disease severity and motor impairment, and can be used to monitor the response to treatment in PD.

Quantitative analysis of language production in Parkinson's disease using a cued sentence generation task

The present study examined language production skills in Parkinson's disease (PD) patients. A unique cued sentence generation task was created in order to reduce demands on memory and attention. Differences in sentence production abilities according to disease severity and cognitive impairments were assessed. Language samples were obtained from 20 PD patients and 20 healthy control participants matched for age, sex and educational level. In addition, a cognitive test for verbal memory and resistance to cognitive interference was administered. Statistical comparisons revealed significant language changes in an advanced stage of the disease. Advanced PD patients showed a reduction in lexical diversity in notional verbs, which was absent in nouns. Cognitive dysfunctions such as impaired verbal memory are suggested to contribute to the typical noun/verb dissociation in PD patients. In addition, advanced PD patients produced more semantic perseverations, which may be related to set-switching problems. In conclusion, whether language disturbances in PD are the result of non-linguistic cognitive dysfunctions or reflect pure language deficits exacerbated by cognitive impairments, remains a matter of debate. However, the negative impact of cognitive dysfunctions may be important.

Verbal fluency in Alzheimer's disease, Parkinson's disease, and major depression

OBJECTIVE

To compare verbal fluency among Alzheimer's disease, Parkinson's disease, and major depression and to assess the sociodemographic and clinical factors associated with the disease severity.

METHODS

Patients from an outpatient university center with a clinical diagnosis of Alzheimer's disease, Parkinson's disease or major depression were studied. Severity was staged using the Hoehn & Yahr scale, the Hamilton Depression scale and the Clinical Dementia Rating for Parkinson's disease, major depression, and Alzheimer's disease, respectively. All subjects were tested with the Mini-Mental State Examination, the digit span test, and the verbal fluency test (animals). We fit four types of regression models for the count variable: Poisson model, negative binomial model, zero-inflated Poisson model, and zero-inflated negative binomial model.

RESULTS

The mean digit span and verbal fluency scores were lower in patients with Alzheimer's disease (n = 34) than in patients with major depression (n = 52) or Parkinson's disease (n = 17) (p<0.001). The average number of words listed was much lower for Alzheimer's disease patients (7.2 words) compared to the patients presenting with major depression (14.6 words) or Parkinson's disease (15.7 words) (KW test = 32.4; p<0.01). Major depression and Parkinson's disease groups listed 44% (ROM = 1.44) and 48% (ROM = 1.48) more words, respectively, compared to those patients with Alzheimer's disease; these results were independent of age, education, disease severity and attention. Independently of diagnosis, age, and education, severe disease showed a 26% (ROM = 0.74) reduction in the number of words listed when compared to mild cases.

CONCLUSIONS

Verbal fluency provides a better characterization of Alzheimer's disease, major depression, and Parkinson's disease, even at later stages.

Clock drawing performance in a community-dwelling population: Normative data for Japanese subjects

OBJECTIVES

The Clock Drawing Test (CDT) is commonly used for cognitive screening. The purpose of this study is to develop normative data for the CDT for the Japanese community-dwelling population, using the method of Freedman. This study also investigates the effect of demographic factors on the performance of the subjects in this task.

METHODS

We administered the CDT and the Mini-Mental State Examination (MMSE) to 873 volunteers. Using a multiple linear regression analysis, we found a gender difference in the free-drawn condition.

RESULTS

A detrimental effect of age was observed in the free-drawn and pre-drawn conditions. The years of education affected the CDT in the examiner 2 condition. Correlations of the MMSE with each of the five conditions of the CDT were significant, further validating this test.

CONCLUSIONS

Our study provides preliminary normative data for the Japanese population stratified by the age and level of education. However, interpretation of our results was hampered by the large variability in the performance of the subjects and the possibility of a selection bias. Thus, additional studies will be necessary to further characterise the CDT scores for the Japanese community.

Depression in Parkinson's disease: clinical-epidemiological correlates and comparison with a controlled group of non-parkinsonian geriatric patients

OBJECTIVE

To evaluate and compare the frequency and severity of major depression in patients with Parkinson's disease and in individuals older than 60 years without neurological, rheumatological and/or oncological comorbidities.

METHOD

We studied 50 patients with Parkinson's disease older than 60 years and 50 geriatric patients. Subjects with scores of Mini Mental State Examination indicating cognitive impairment were excluded. We used Diagnostic Statistical Manual of Mental Diseases-IV criteria to diagnose major depression and the Hamilton Depression Scale and the Beck Depression Inventory to rate it. The Unified Parkinson's Disease Rating Scale part 3 and the Hoehn and Yahr Scale were used to evaluate the motor severity of Parkinson's disease.

RESULTS

Major depression was found in 42% of Parkinson's disease patients and in 10% of the geriatric patients (p < 0.001). The scores of the Hamilton Depression Scale and the Beck Depression Inventory were higher in Parkinson's disease patients (p < 0.001). Depressed Parkinson's disease patients had longer duration of Parkinson's disease (p = 0.020) and higher scores on the Unified Parkinson's Disease Rating Scale part 3 (p = 0.029) and the Yahr Scale (p = 0.027).

CONCLUSIONS

The frequency (42%) and severity of major depression were higher in Parkinson's disease patients. Longer duration of Parkinson's disease, higher scores on the Unified Parkinson's Disease Rating Scale part 3 and the Hoehn and Yahr Scale were significantly associated with major depression.

Age and educational level effects on the performance of normal elderly on category verbal fluency tasks

Cognitive decline, particularly executive dysfunction, is observed in normal aging. In Brazil, the elderly population presents broad educational diversity. Category verbal fluency tests are frequently used to detect cognitive impairment, assessing executive function, language and semantic memory.

Objective

To investigate the effects of age and education on category animal fluency task (CAF) in healthy elderly.

Methods

We evaluated 319 healthy elderly from outpatient care units of two university reference centers of Rio de Janeiro and São Paulo. The sample was divided into two age, and five schooling subgroups. To be included participants had to demonstrate preservation of global cognitive functioning, independence for activities of daily living and not fulfill diagnostic criteria for dementia. All participants were submitted to neurological and neuropsychological evaluations.

Results

There was a correlation between age and CAF performance (r= -0.26, p<0.01), which was not confirmed when years of education were included as a covariant in univariate ANCOVA. Significant differences were found in CAF performance among the different educational level groups on correlation analysis (r=0.42, p<0.01) and ANCOVA analysis (F=18.8, p<0.05). Illiteracy was associated with worst CAF performance, while university level was associated with best performance.

Conclusion

The best CAF performance was found in the first years of schooling (literacy learning process) compared to illiteracy, and when finishing high school and starting university courses compared to all other educational levels. These stages are associated with significant gains in semantic memory and executive function which are critical for verbal fluency performance.

Dementia with Parkinson disease: Clinical diagnosis, neuropsychological aspects and treatment

Dementia with Parkinson's disease represents a controversial issue in the complex group of alpha-synucleinopathies. The author acknowledges the concept of a "continuum" between Parkinson disease's (PD), Lewy body dementia (LBD), and dementia in Parkinson's disease (PDD). However, the practicing neurologist needs to identify the phenotypic signs of each dementia. The treatment and prognosis are different in spite of the overlaps between them. The main aim of this review was to characterize the clinical diagnoses of dementia associated with Parkinson's disease (PDD). Secondarily, the review discussed some epidemiological and neuropsychological issues. Selection of articles was not systematic and reflects the author's opinion, where the main text selected was the recommendations from the Movement Disorder Society Task Force for PDD diagnosis. The Pub Med, OVID, and Proquest data bases were used for the search.

Visuospatial cognitive tests for the evaluation of patients with Parkinson's disease

Parkinson's disease (PD) is a neurological disorder characterized by motor disturbances, neuropsychological symptoms and cognitive changes, including cases of dementia. The most frequently described cognitive changes in these patients involve executive and visuospatial functions, which are very important for the execution of daily life activities.

Objective

To compare different tests used to examine visuospatial functions in patients with PD.

Methods

Thirty-five patients (21 women) with PD symptoms (medicated and "on") and mean schooling of 5.5±4.2 years were examined using the following tests: Mini-Mental State Examination (MMSE), Dementia Rating Scale (DRS), Scales of Outcomes of Parkinson's Disease (SCOPA-COG), Hooper Visual Organization Test (HVOT), Judgment of Line Orientation, Form V (JLO), and Clock drawing task - CLOX (1 and 2).

Results

The mean MMSE score was 24.8±3.03and 54.8% of the patients performed correctly in the copy of a pentagon drawing, with a medium-level performance in most tests. Good correlations were detected between JLO versus SCOPA Assembling patterns (0.67), JLO versus HVOT (0.56), JLO versus CLOX2 (0.64), SCOPA Figure Composition versus HVOT (0.54), CLOX1 versus CLOX2 (0.43), and DRS Construction versus CLOX2 (0.42).

Discussion

Although correlations were detected, not all were strong, probably because the tests employed do not measure solely visuospatial functions, but also other skills such as attention, motor ability and executive functions. A limitation of the present study was the lack of a control group for the establishment of adequate standards for this population.