Education-corrected CERAD identifies MCI and dementia in Parkinson's disease.

OBJECTIVES: This study examined whether controlling for educational background in the CERAD cognitive screening battery would affect the likelihood of patients with Parkinson's disease to fulfill criteria for mild cognitive impairment (PD-MCI) and dementia (PDD). MATERIALS & METHODS: One-hundred seventeen patients with PD were studied. Cognitive impairment was determined as two subtest scores falling below either the standard cutoff scores or education-corrected cutoff scores. The presence of dementia was determined by clinical interview or Clinical Dementia Rating. Patients were then classified as PD-MCI and PDD according to cognitive test performance and presence/absence of dementia. RESULTS: The number of cognitively impaired patients (PD-MCI or PDD) was significantly higher when education-controlled cutoff scores were used (62.5% vs 38%). Correspondingly, the number of false negatives (demented PD patients performing normally in CERAD) was significantly lower when education-corrected cutoff scores were used (4% vs 10%). CONCLUSIONS: Controlling for education increases the sensitivity of the CERAD for PD-MCI and PDD.

CERAD test performance and cognitive impairment in Parkinson's disease.

OBJECTIVES: Many patients with Parkinson's disease (PD) develop mild cognitive impairment (PD-MCI) and dementia (PDD). The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neurocognitive test battery was originally developed to identify early Alzheimer's disease, but it has become a widely used screening instrument also for other types of dementia. The aim of the study was to examine differences in CERAD test performances between cognitively intact and impaired PD patients. MATERIALS AND METHODS: Eighty-eight PD patients participating in a rehabilitation course were studied. The Clinical Dementia Rating (CDR) was used to assess cognitive impairment. Sixty-six patients were cognitively intact and 22 had cognitive impairment (≥1 in two or more domains or a sum of boxes score of ≥3). The Finnish CERAD test battery was used to measure cognitive functions in seven different domains (language functions, verbal learning, visuospatial functions, delayed recall, memory consolidation, recognition memory, and executive functions). RESULTS: There were significant differences between the cognitively intact and impaired patients in six CERAD subtests (wordlist learning sum, wordlist delayed recall, constructional praxis recall, clock drawing, verbal fluency and constructional praxis copy) when controlling for covariates (disease duration, motor symptoms, age, and education). No differences were observed in memory consolidation scores. CONCLUSIONS: The results indicate that mild cognitive impairment in PD is related to deficits in memory, executive functions, and visuospatial functions. The memory deficit is non-amnestic and does not entail accelerated forgetting. CERAD shows promise in identifying PD patients with cognitive impairment and increased risk of dementia.

Apathy is associated with activities of daily living ability in Parkinson's disease.

BACKGROUND: Neuropsychiatric symptoms and impairment in performing activities of daily living (ADL) in patients with Parkinson's disease (PD) are strong predictors of the overall caregiver burden and they increase the risk for nursing home admission of the patients. The purpose of the present study was to assess the association of neuropsychiatric symptoms and ADL functions in PD. METHODS: A total of 73 community-dwelling PD patients were studied. The mean age of the patient group was 65 years and the mean disease duration was 9 years. The Neuropsychiatric Inventory was used to measure neuropsychiatric symptoms, and ADL abilities were measured by the Alzheimer's Disease Cooperative Study-Activities of Daily Living Inventory. RESULTS: The prevalence of neuropsychiatric symptoms in patients with PD was 73%. The most common symptoms were depression, anxiety, irritability, apathy and agitation. ADL ability correlated significantly with apathy (p < 0.002) even when adjusted for motor symptoms. CONCLUSION: Apathy was significantly associated with ADL in PD. The result indicates that more attention should be paid to identifying apathy and targeting therapeutic interventions.

Visual object recognition in early Alzheimer's disease: deficits in semantic processing.

OBJECTIVES: The purpose of the present study was to divide visual object recognition into different stages and to reveal which of these stages are impaired in early Alzheimer's disease (AD). METHODS: Performance in object detection, familiarity detection, semantic name and word categorization, and identification with naming were studied by using two-choice reaction-time tasks. Ten patients with newly diagnosed AD and 14 healthy subjects were studied. RESULTS: Patients with early AD had impairments in several stages of the object recognition process. After controlling for the basic visuomotor slowness, they were as fast and as accurate as the controls in object detection, but had difficulties in all stages that required semantic processing. CONCLUSIONS: Semantic memory impairments contribute to the deficits in visual object recognition in early AD. Thus, the semantic memory deficit may be manifested in several ways in the difficulties that AD patients experience in everyday life.

Visual object recognition in multiple sclerosis.

Deficits in tasks measuring visual processing have been earlier reported in studies of MS. Yet, the nature and severity of visual-processing deficits in MS remains unclear. We used a new method in order to measure the different stages of visual processing in object recognition: shape recognition, familiarity recognition, semantic categorization, and identification with naming. Six two-choice reaction-time tasks were presented to 30 MS patients and 15 healthy controls. The patients were divided into cognitively preserved and cognitively deteriorated study groups according to their cognitive status. The purpose was to find out whether deficits at specific stages of visual processing can be found in cognitively deteriorated MS patients. Cognitively deteriorated MS patients did not perform as well as cognitively preserved MS patients or healthy controls. They were slower already at the early stage of visual processing where discrimination of whole objects from scrambled ones was required. They also had higher error rates in tasks requiring object familiarity detection and object identification with naming. Thus, cognitively deteriorated MS patients had difficulties in visual shape recognition and semantic-lexical processing. However, variation of performances was large within both of the patient groups indicating that even patients without a generalized cognitive decline may have deficits in some stages of the visual processing. We suggest that because of the heterogeneity of the patients, every single case needs to be examined separately in order to identify the possible deficits in visual processing.

Impairment of semantic knowledge in Parkinson disease.

BACKGROUND: Parkinson disease (PD) is commonly characterized by cognitive deterioration, but it is still unclear whether PD is associated with semantic impairments. OBJECTIVE: To evaluate semantic knowledge of concepts in patients with idiopathic PD, addressing concrete and abstract concepts, conceptual attributes, and conceptual relations. METHODS: Twelve patients with preserved cognitive status, 12 patients with mildly deteriorated cognitive status, and 12 control subjects were studied. The cognitive status of patients and controls was determined using detailed cognitive testing. Patients were participants in a university-based movement disorder program, and their PD diagnoses were clinically confirmed during long-term follow-up. The 2 patient groups were similar in age, level of education, disease duration, and parkinsonian disability. Patients were required to produce verbal descriptions of concrete and abstract concepts, to give ratings of the importance of concept attributes, and to assess and construct conceptual hierarchies. The description tasks included guiding questions, which were used if the spontaneous productions of the patients lacked any essentials expected in the answers. RESULTS: Patients with mild cognitive deterioration performed less well than the other groups in defining concrete and abstract concepts (P<.001 for both). External guidance did not help them markedly improve their performance. They also had difficulties in tasks calling for knowledge of the importance of given attributes to the concepts and in tasks demanding evaluation of hierarchical semantic relations between concepts (P<.001 for both). CONCLUSION: Semantic disruption is implied in idiopathic PD in association with incipient cognitive impairment.

Sematic memory deficit in multiple sclerosis; impaired understanding of conceptual meanings.

The aim of the present study was to determine whether a cognitive decline, related to multiple sclerosis (MS), also involves deficits in semantic memory. Semantic memory function was evaluated by studying the conscious understanding of conceptual meanings. A group of MS patients with cognitive decline was presented with four tasks concerning concepts, their attributes and relationships to other concepts. The tasks were designed to measure spontaneous, cued and recognition performance separately. The patients had difficulties in understanding conceptual meanings. Easing the retrieval demands of the tasks did not help them to improve their performance which was poorer than the control group's on every task used. The results indicate a retrieval deficit combined with an underlying storage deficit in the semantic memory of MS patients with cognitive decline.

Knowledge of concept meanings in Alzheimer's disease.

The present study focuses on semantic deficits in Alzheimer's disease (AD). We distinguish three different levels of semantic knowledge: (1) lexical, (2) semantic-conceptual, (3) conscious understanding. We devised methods that tap levels (2) and (3). Our aim was to determine how much guidance AD patients need to consciously access a given semantic-conceptual field and how well they can understand the meanings of concepts and semantic relations. Four different tasks were used to tap different kinds of concepts, the relationships between concepts and their attributes, and the hierarchical structure among different concepts. The retrieval demands of the tasks were eased by presenting guiding questions. The results revealed that AD patients have deficient voluntary access to semantic-conceptual representations. The deficits persist even in passive recognition and forced-choice tasks. We conclude that AD patients have a generalized access deficit, although some aspects of the results are suggestive of storage deficit.