Cândida H. P. Camargo

Relation between medial temporal atrophy and functional brain activity during memory processing in Alzheimer’s disease: a combined MRI and SPECT study

Objective: To investigate the relation between atrophy of the hippocampal region and brain functional patterns during episodic memory processing in Alzheimer’s disease. Patients and methods: Whole brain structural magnetic resonance imaging (MRI) data and single photon emission computed tomography (SPECT) measures of regional cerebral blood flow (rCBF) were obtained during a verbal recognition memory task in nine subjects with mild Alzheimer’s disease and 10 elderly healthy controls. Using the statistical parametric mapping approach, voxel based comparisons were made on the MRI data to identify clusters of significantly reduced grey matter concentrations in the hippocampal region in the Alzheimer patients relative to the controls. The mean grey matter density in the voxel cluster of greatest hippocampal atrophy was extracted for each Alzheimer subject. This measure was used to investigate, on a voxel by voxel basis, the presence of significant correlations between the degree of hippocampal atrophy and the rCBF SPECT measures obtained during the memory task. Results: Direct correlations were detected between the hippocampal grey matter density and rCBF values in voxel clusters located bilaterally in the temporal neocortex, in the left medial temporal region, and in the left posterior cingulate cortex during the memory task in the Alzheimer’s disease group (p < 0.001). Conversely, measures of hippocampal atrophy were negatively correlated with rCBF values in voxel clusters located in the frontal lobes, involving the right and left inferior frontal gyri and the insula (p < 0.001). Conclusions: Hippocampal atrophic changes in Alzheimer’s disease are associated with reduced functional activity in limbic and associative temporal regions during episodic memory processing, but with increased activity in frontal areas, possibly on a compensatory basis.

The short cognitive performance test (SKT) : a preliminary study of its psychometric properties in Brazil

BACKGROUND Most instruments designed to detect dementia can lack appropriate sensitivity in the early stages of Alzheimers disease (AD), and are subject to educational bias. The Short Cognitive Performance Test (Syndrom-Kurztest, SKT) is considered a suitable instrument to measure cognitive decline as it assesses memory, attention, and related cognitive functions, taking into account the speed of information processing. OBJECTIVES The aim of this study was to examine the psychometric characteristics of the SKT as a dementia screening instrument in a Brazilian population sample, as compared to the Mini-mental State Examination (MMSE) and the Clock-Drawing Test (CDT). The effect of educational level on performance in the three screening tests was also verified. METHODS Fifty-one elderly subjects were assessed. Consensus diagnoses were established by an expert multidisciplinary team, considering clinical, neuropsychological and neuroimaging data. Subjects were further classified into those with (1) mild and moderate AD, (2) non-Alzheimers dementia, (3) mild cognitive impairment, and (4) controls, according to National Institute for Communicative Disorders and Stroke--Alzheimers Disease and Related Disorders Association (NINCDS-ADRDA) criteria. RESULTS Statistical analyses revealed high internal consistency for the SKT (Cronbachs alpha = 0.80) and significant correlations between the total score and the SKT subscores separately (p < 0.01). Comparison of the three tests revealed strong correlations between the SKT and the MMSE (r = -0.66, p < 0.0001) and between the SKT and the CDT (r = -0.57, p < 0.0001). The SKT, MMSE and CDT scores were correlated with education. CONCLUSIONS The Brazilian version of the SKT maintains its original psychometric properties and displays significant correlation with previously validated screening tools for dementia. Like other dementia screening tests, the SKT is subject to educational bias.

Development of an adapted version of the Boston Naming Test for Portuguese speakers

OBJECTIVE To present the development of an adapted version of the Boston Naming Test for Portuguese speakers, and to investigate the effects of age, education and gender on both the original and the adapted Boston Naming Test in respect of Brazilian Portuguese speakers. METHOD Eighty items, including the 60 original ones and 20 adapted items were administered to 739 healthy Brazilian subjects aged between 6 and 77 years who received 0 to 17 years of education. RESULTS The coefficients of the General Linear Model estimation suggested that both age and education were statistically significant to predict total scores. In addition, score variances, justified by such predictors, were 41.20% in the original Boston Naming Test against 25.84% in the adapted Boston Naming Test. These results suggest that the scores from the original BNT are more dependent on age and education than those from the adapted Boston Naming Test. CONCLUSION These findings demonstrated the suitability of the adapted Boston Naming Test version for the Brazilian population and described provisional norms for the original and adapted Boston Naming Test for Portuguese speakers.

P3-050: Preliminary analyses of the psychometric characteristics of the Rivermead Behavioural Memory Test (RBMT) as an early detection instrument for AD in Brazil

Test, more difficulties in the resolution of more complex tasks were observed (Part B .052). Conclusions: The course of the Cognitive Aging (CA) during the time seems to behave in a heterogeneous way; however, a bigger cognitive deterioration in some abilities does exist involving learning, especially when it depends on executive functions. A bias to develop a delay and a fatigue in similar tasks through repeated times also exist, mainly when those tasks involve cognitive flexibility. Other functions such as language, semantic memory, and attention (in its simple form), have remained steady or scored better in T2, indicating possible practice effect.

Assessment of memory complainers in São Paulo, Brazil Three-year results of a memory clinic

Memory clinics were established in the USA and European countries as services to attend patients who complain of cognitive deficits, referred by primary care doctors, specialists and other hospitals. Objective We aimed to describe the clinical and cognitive profile of consecutively evaluated subjects during the initial three years of service of a memory clinic from a university hospital. Methods Subjects were submitted to a clinical work-up for dementia, which included laboratory exams, cranial computerized tomography, cognitive tests, and a comprehensive neuropsychological battery. Diagnosis was made according to ICD-10 criteria. Results We evaluated 104 subjects (67.3% females and 32.7% males), with mean age of 59.1 years, 88.8% aged 50 years or above. Mean schooling was 9.9 years. Patients were classified into 10 different primary diagnostic categories, namely Depression (26.9%), Alzheimer’s disease (17.3%), Memory complaints without objective impairment (17.3%), Mild Cognitive Disorder – MCD (14.4%), and Anxiety (12.5%) the most frequent diagnosis. Comparing patients with dementia, MCD, Depression or Anxiety and Memory complainers, by age (below and above 60 years), dementia was more commonly diagnosed in older subjects, while a higher frequency of memory complainers was found in the younger group. Conclusions This preliminary report from an outpatient group of referred patients with cognitive complaints showed a higher frequency of psychiatric disorders in this sample. The memory clinic approach should be considered as a model of service which can evaluate subjects with cognitive complaints effectively and improve the quality of care delivered to this patient group.