Louis Verret

The Value of PET in Mild Cognitive Impairment, Typical and Atypical/Unclear Dementias: A Retrospective Memory Clinic Study

This retrospective study examined the role of [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) in the diagnosis of atypical/unclear dementias in a memory clinic setting. A total of 94 patients with a diagnosis of mild cognitive impairment (MCI) or dementia, who had a PET study within 2 months of their diagnosis, were reevaluated at 5 and 18 months. Results showed that PET was associated with a change in diagnosis in 29% of patients and a 64% increase in the use of cholinesterase inhibitors (ChEIs). PET significantly lowered the number of atypical/unclear diagnoses from 39.4% to 16% and nearly 30% of these were found to have a typical Alzheimer’s disease (AD) pattern of hypometabolism. In conclusion, the addition of PET to the investigation of atypical/unclear cases of dementia helped generating a more accurate diagnosis and initiating earlier treatment. PET was of limited contribution to typical AD and frontotemporal dementia (FTD) cases. This study provides guiding evidence about the true value of PET imaging in the day-to-day challenge of dementia diagnosis.

Cognitive estimation impairment in Alzheimer disease and mild cognitive impairment.

Intact executive functioning is believed to be required for performance on tasks requiring cognitive estimations. This study used a revised version of a cognitive estimations test (CET) to investigate whether patients with Alzheimers disease (AD) and mild cognitive impairment (MCI) were impaired on the CET compared with normal elderly controls (NECs). Neuropsychological tests were administered to determine the relationship between CET performance and other cognitive domains. AD patients displayed impaired CET performance when compared with NECs but MCI patients did not. Negative correlations between tests of working memory (WM) and semantic memory and the CET were found in NECs and AD patients, indicating that these cognitive domains were important for CET performance. Regression analysis suggests that AD patients were unable to maintain semantic information in WM to perform the task. The authors conclude that AD patients display deficits in working memory, semantic memory, and executive function, which are required for adequate CET performance.

The Relation Between Depressive Symptoms and Semantic Memory in Amnestic Mild Cognitive Impairment and in Late-Life Depression

Semantic deficits have been documented in the prodromal phase of Alzheimers disease, but it is unclear whether these deficits are associated with non-cognitive manifestations. For instance, recent evidence indicates that cognitive deficits in elders with amnestic mild cognitive impairment (aMCI) are modulated by concomitant depressive symptoms. The purposes of this study were to (i) investigate if semantic memory impairment in aMCI is modulated according to the presence (aMCI-D group) or absence (aMCI group) of depressive symptoms, and (ii) compare semantic memory performance of aMCI and aMCI-D groups to that of patients with late-life depression (LLD). Seventeen aMCI, 16 aMCI-D, 15 LLD, and 26 healthy control participants were administered a semantic questionnaire assessing famous person knowledge. Results showed that performance of aMCI-D patients was impaired compared to the control and LLD groups. However, in the aMCI group performance was comparable to that of all other groups. Overall, these findings suggest that semantic deficits in aMCI are somewhat associated with the presence of concomitant depressive symptoms. However, depression alone cannot account solely for the semantic deficits since LLD patients showed no semantic memory impairment in this study. Future studies should aim at clarifying the association between depression and semantic deficits in older adults meeting aMCI criteria. (JINS, 2011, 17, 865-874).

Semantic Memory Impairment for Biological and Man-Made Objects in Individuals With Amnestic Mild Cognitive Impairment or Late-Life Depression

Objective: Amnestic mild cognitive impairment (aMCI) and late-life depression (LLD) both increase the risk of developing Alzheimer disease (AD). Very little is known about the similarities and differences between these syndromes. The present study addresses this issue by examining the nature of semantic memory impairment (more precisely, object-based knowledge) in patients at risk of developing AD. Methods: Participants were 17 elderly patients with aMCI, 18 patients with aMCI plus depressive symptoms (aMCI/D+), 15 patients with LLD, and 29 healthy controls. All participants were aged 55 years or older and were administered a semantic battery designed to assess semantic knowledge for 16 biological and 16 man-made items. Results: Overall performance of aMCI/D+ participants was significantly worse than the 3 other groups, and performance for questions assessing knowledge for biological items was poorer than for questions relating to man-made items. Conclusion: This study is the first to show that aMCI/D+ is associated with object-based semantic memory impairment. These results support the view that semantic deficits in aMCI are associated with concomitant depressive symptoms. However, depressive symptoms alone do not account exclusively for semantic impairment, since patients with LLD showed no semantic memory deficit.

MCI progressors and non-progressors: Neuropsychological profiles fail to guarantee the prognosis

al., 2005). Objective(s): The purpose of this study was to use voxel-based morphometry (VBM) to assess regional gray matter atrophy related to judgment ability. We hypothesized that the neural basis for impaired judgment skills would involve prefrontal cortical regions. Methods: Participants (N 119) were euthymic older adults including patients with mild Alzheimer’s disease, patients with amnestic mild cognitive impairment, individuals with cognitive complaints but normal neuropsychological test performance, and demographically-matched healthy controls. Structural MR scanning included a T1-weighted 1.5mm coronal volume, acquired on a GE 1.5T LX scanner. For VBM, SPGR volumes were spatially normalized, segmented, smoothed, and gray matter images analyzed using the GLM approach implemented in SPM. We used SPM to identify brain areas where gray matter was correlated with DRJQ total scores in the entire sample. Results: Using a critical significance threshold of .001 at the voxel level and a minimum cluster size of 50 voxels (1.69 cm), results indicated that impaired judgment skills correlated with atrophy of bilateral frontal and temporal lobe regions. To control for the apparent relationship with memory in our sample of participants with memory complaints and/or dysfunction, we created an adjusted DRJQ score, factoring out the effects of memory performance (i.e., CVLT-II Total Learning score). Using a critical significance threshold of .005, the remaining correlation was with the right middle frontal gyrus (Figure 1). Conclusions: Results extendprevious validation of the DRJQ as a measure of judgment abilities in older adults by providing evidence of its selective relationship with frontal integrity. Longitudinal assessments are being performed to examine predictive validity of the DRJQ for cognitive progression in our clinical groups.

DÉ́PISTAGE COGNITIF DE QUÉBÉC (DCQ): VALIDATION AND NORMATIVE DATA FOR A NOVEL COGNITIVE SCREENING TOOL FOR ATYPICAL DEMENTIAS

Mental State Examination, the original version of the MoCA, and the quality of life scale CASP-19. A multiple regression analysis was performed to verify the influence of age and education and the predictive capacity of the original version of the test on its alternative version. Results: Cronbach’s alpha coefficient was .76. Elimination of any of the items of the 2 version of MoCA never reduces the reliability to below .73. Convergent validity was .65 (p<.001), and divergent validity was .03 (p1⁄40.79). Correlation between the 1 and the 2 version of MoCA was significant and high (r1⁄40.86). There was a negative effect of age (b 1⁄4–0.141, p < 0.01) and a positive effect of education (b 1⁄4–0.549, p < 0.001), but these two effects did not remained significant when the total score of the original form of MoCA was included in the regression model (b1⁄4–0.691, p < 0.001) (Figure1). Conclusions: Our preliminary results showed good psychometrical properties for the 2nd alternative form of the Spanish version and strong relations between forms. Further analyses are required in order to guarantee the use of the alternate Spanish version of the MoCA test in clinical follow-ups and longitudinal studies.

Clinical utility of amyloid PET in the differential diagnosis of atypical dementias and its impact on caregivers

not available. PL-04-02 BIOCHEMICALLY BASED QUANTITATIVE NEUROPATHOLOGY IN CLINICAL

Clinical utility of amyloid imaging in the differential diagnosis of atypical/unclear dementias and its impact on caregivers

Recent studies have supported a role for amyloid positron emission tomography (PET) imaging in distinguishing Alzheimer’s disease (AD) pathology from other pathological protein accumulations leading to dementia. We investigated the clinical utility of amyloid PET in the differential diagnosis of atypical dementia cases and its impact on caregivers. Using the amyloid tracer 18F-NAV4694, we prospectively scanned 28 patients (mean age 59.3 y, s.d. 5.8; mean MMSE 21.4, s.d. 6.0) with an atypical dementia syndrome. Following a comprehensive diagnostic workup (i.e., history taking, neurological examination, blood tests, neuropsychological evaluation, MRI, and FDG-PET), no certain diagnosis could be arrived at. Amyloid PET was then conducted and classified as positive or negative. Attending physicians were asked to evaluate whether this result led to a change in diagnosis or altered management. They also reported their degree of confidence in the diagnosis. Caregivers were met after disclosure of amyloid PET results and completed a questionnaire/interview to assess the impact of the scan. Our cohort was evenly divided between positive (14/28) and negative (14/28) 18F-NAV4694 cases. Amyloid PET resulted in a diagnostic change in 9/28 cases (32.1%: 17.8% changed from AD to non-AD, 14.3% from non-AD to AD). There was a 44% increase in diagnostic confidence. Altered management occurred in 71.4% (20/28) of cases. Knowledge of amyloid status improved caregivers’ outcomes in all domains (anxiety, depression, disease perception, future anticipation, and quality of life). This study suggests a useful additive role for amyloid PET in atypical cases with an unclear diagnosis beyond the extensive workup of a tertiary memory clinic. Amyloid PET increased diagnostic confidence and led to clinically significant alterations in management. The information gained from that test was well received by caregivers and encouraged spending quality time with their loved ones.

CIMA-Q: QUEBEC’S CONSORTIUM TO IDENTIFY PRODROMAL ALZHEIMER'S DISEASE

N 57 32 18 7 PRACTICE Drag & Drop (0-3) null Mean 3 3 3 3 SD 0 0 0 0 Random Button Success (0-3) null Mean 3 3 3 3 SD 0 0 0 0 Task Successful (Yes) null Freq 57 32 18 7 % 100 100 100 100 Time Elapsed (sec) <0.0001 Mean 24.89 21.72 26.84 34.35 SD 7.53 3.65 8.52 9.21 FACES Total Score (0-3) 0.05 Mean 2.49 2.72 2.17 2.29 SD 0.81 0.58 0.99 0.95 Task Successful (Yes) Freq 37 25 8 4 0.05 % 65 78 44 57 Time Elapsed (sec) 0.04 Mean 121.2 116.0 123.1 139.8 SD 23.0 FACES & NAMES Total Score (0-6) 0.04 Mean 4.09 4.47 3.56 3.71 SD 1.31 1.11 1.58 0.95 Task Successful (Yes) 0.41 Freq 8 6 2 0 % 14 18.8 11.1 0.0 Time elapsed (sec) 0.0003 Mean 153.17 148.21 154.34 172.80 b SD 15.59 11.42 17.93 9.95 ATM PIN Attempts 0.03 Mean 1.23 1.03 a 1.50 a 1.43 SD 0.66 0.18 0.86 1.13 PIN Time (sec) 0.002 Mean 17.29 10.58 24.56 29.27 SD 16.56 8.09 19.73 23.52 Time Elapsed (sec) 0.0002 Mean 113.6 96.10 125.6 163.2 SD 44.0 28.7 42.2 62.0 Task Successful (Yes) 0.004 Freq 36 25 10 1 % 63 78 56 14 PHONE Main Menu Visits 0.023 Mean 1.32 1.06 1.67 1.57 SD 0.81 0.25 1.08 1.27 Pharm Menu Visits 0.0017 Mean 0.96 1.03 1.00 0.57 SD 0.32 0.18 0.34 0.53 Refilled Rx (Yes) 0.0007 Freq 47 31 13 3 % 82 97 72 43 Rx Number Time (sec) 0.007 Mean 38.4 34.81 a 37.53 80.40 SD 24.6 21.2 19.8 46.6 Task Successful (Yes) 0.0007 Freq 47 31 13 3 % 82 97 72 43 Time Elapsed (sec) 0.039 Mean 127.8 113.7 143.9 151.2 SD 48.3 33.5 47.6 84.4 (Continued ) Table 1 (Continued )

Semantic memory for objects in individuals with mild cognitive impairment and depressive symptoms

INDIVIDUALS WITH MILD COGNITIVE IMPAIRMENTAND DEPRESSIVE SYMPTOMS Brandy Callahan, Sven Joubert, Jo€el Macoir, Sylvie Belleville, Francois Rousseau, Louis Verret, Marie-Jeanne Kergoat, Carol Hudon, Universit e Laval, Quebec, Quebec, Canada; Universit e de Montr eal, Montreal, Quebec, Canada; 3 Universit e Laval, Qu ebec, Quebec, Canada; ResearchCenter, Institut Universitaire de G eriatrie deMontr eal, Montreal, Quebec, Canada; Institut Universitaire en Sant e Mentale de Qu ebec, Quebec, Quebec, Canada; 6 Hôpital de l’Enfant-J esus du CHA de Qu ebec, Quebec, Quebec, Canada; 7 Centre de Recherche de l’Institut Universitaire de G eriatrie de Montr eal, Montreal, Quebec, Canada.