Cut-off score of the Mattis Dementia Rating Scale for screening dementia in Parkinson's disease

Executive functions deficit in Parkinson's disease with amnestic mild cognitive impairment

Recent studies suggest that onset of dementia in Parkinson's disease (PD) is preceded by a phase known as mild cognitive impairment (MCI). Different clinical subtypes of MCI in PD were found. The objective of this study was to investigate whether patients with PD diagnosed with amnestic MCI (aPD-MCI) have also subtle deficits in other cognitive domains and especially in attention/executive functions and, therefore to clarify whether all subcomponents of executive control are equally affected in aPD-MCI. We investigated 23 patients with aPD-MCI (modified Petersen's criteria) and 25 normal controls. Relative to controls, the aPD-MCI group showed significant deficits with reference to tasks that encompass various aspects of attention/executive functions, including Trail Making Test, Stroop test, Modified Card Sorting Test, and digit span backward, as well as phonemic and semantic verbal fluency. This suggests that executive dysfunction is consistently presented in PD with MCI, even in ''amnestic'' PD-MCI due to cortical-subcortical dysfunction.

Impaired emotion recognition in music in Parkinson's disease

Music has the potential to evoke strong emotions and plays a significant role in the lives of many people. Music might therefore be an ideal medium to assess emotion recognition. We investigated emotion recognition in music in 20 patients with idiopathic Parkinson's disease (PD) and 20 matched healthy volunteers. The role of cognitive dysfunction and other disease characteristics in emotion recognition was also evaluated. We used 32 musical excerpts that expressed happiness, sadness, fear or anger. PD patients were impaired in recognizing fear and anger in music. Fear recognition was associated with executive functions in PD patients and in healthy controls, but the emotion recognition impairments of PD patients persisted after adjusting for executive functioning. We found no differences in the recognition of happy or sad music. Emotion recognition was not related to depressive symptoms, disease duration or severity of motor symptoms. We conclude that PD patients are impaired in recognizing complex emotions in music. Although this impairment is related to executive dysfunction, our findings most likely reflect an additional primary deficit in emotional processing.

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.

[Parkinson's disease dementia: correlations between clinical, neuropsychological and neuropathological features]

INTRODUCTION

Cognitive disorders such as deficit of attention and executive and visuoconstructive dysfunctions occur in Parkinson's disease dementia (PDD). Memory impairment is not an early feature and statement not well delimited.

CASE REPORT

A 78-year-old man with PDD underwent neuropsychological assessment and moreover demonstrated memory decline. After death, pathology examination of the brain and immunohistochemy analysis confirmed PD and showed Lewy body pathology (LBP) in the insula, limbic and especially in CA3 hippocampus areas. Hippocampus and gyrus parahippocampic also exhibited neurofibrillary tangles. Lack of senile plaque and lack of beta A4 amyloid deposition were noticeable in the whole brain examination.

CONCLUSION

Severe executive dysfunctions are probably related to LBP and dysfunction in memory process may be related to DNF lesions in medial temporal area.

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.