Alzheimer's Disease and Vascular Dementia: Neuropsychological Differentiation in Clinical Practice

Even when well-defined patient groups are studied, neuropsychological differentiation between Alzheimer's disease (dementia of the Alzheimer's type [DAT]) and vascular dementia (VaD) is far from clear. How useful are the results of these investigations when a differential diagnosis has to be established with non–pre-selected individual patients? In the present research we worked with a group of patients pre-diagnosed as having either DAT or VaD. Within the learning abilities, we focused on the status of the encoding system in each condition. Neuropsychological data were compared with PET data. We concluded that within certain limits a few neuropsychological data can contribute substantially to such differentiation, as long as they are contrasted with the rest of the relevant information available.     

Exceptional Parental Longevity Associated with Lower Risk of Alzheimer's Disease and Memory Decline

OBJECTIVES: To determine whether offspring of parents with exceptional longevity (OPEL) have a lower rate of dementia than offspring of parents with usual survival (OPUS). DESIGN: Community‐based prospective cohort study. SETTING: Bronx, New York. PARTICIPANTS: A volunteer sample of 424 community‐residing older adults without dementia aged 75 to 85 recruited from Bronx County starting in 1980 and followed for up to 23 years. MEASUREMENTS: Epidemiological, clinical, and neuropsychological assessments were completed every 12 to 18 months. OPEL were defined as having at least one parent who reached the age of at least 85. OPUS were those for whom neither parent reached the age of 85. Dementia was diagnosed according to case conference consensus based on Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised, criteria without access to information on parental longevity. Alzheimer's disease was diagnosed using established criteria. RESULTS: Of 424 subjects, 149 (35%) were OPEL, and 275 (65%) were OPUS. Mean age at entry for both groups was 79. The OPEL group had a lower incidence of Alzheimer's disease (hazard ratio=0.57, 95% confidence interval=0.35–0.93). After adjusting for sex, education, race, hypertension, myocardial infarction, diabetes mellitus, and stroke, results were essentially unchanged. OPEL also had a significantly lower rate of memory decline on the Selective Reminding Test (SRT) than OPUS (P=.03). CONCLUSION: OPEL develop dementia and Alzheimer's disease at a significantly lower rate than OPUS. Demographic and medical confounders do not explain this result. Factors associated with longevity may protect against dementia and Alzheimer's disease.     

Hospitalization in Community‐Dwelling Persons with Alzheimer's Disease: Frequency and Causes

OBJECTIVES: To examine the rates of and risk factors for acute hospitalization in a prospective cohort of older community‐dwelling patients with Alzheimer's disease (AD). DESIGN: Longitudinal patient registry. SETTING: AD research center. PARTICIPANTS: Eight hundred twenty‐seven older persons with AD. MEASUREMENTS: Acute hospitalization after AD research center visit was determined from a Medicare database. Risk factor variables included demographics, dementia‐related, comorbidity and diagnoses and were measured in interviews and according to Medicare data. RESULTS: Of the 827 eligible patients seen at the ADRC during 1991 to 2006 (median follow‐up 3.0 years), 542 (66%) were hospitalized at least once, and 389 (47%) were hospitalized two or more times, with a median of 3 days spent in the hospital per person‐year. Leading reasons for admission were syncope or falls (26%), ischemic heart disease (17%), gastrointestinal disease (9%), pneumonia (6%), and delirium (5%). Five significant independent risk factors for hospitalization were higher comorbidity (hazard ratio (HR)=1.87, 95% confidence interval (CI)=1.57–2.23), previous acute hospitalization (HR=1.65, 95% CI=1.37–1.99), older age (HR=1.51, 95% CI=1.26–1.81), male sex (HR=1.27, 95% CI=1.04–1.54), and shorter duration of dementia symptoms (HR=1.26, 95% CI=1.02–1.56). Cumulative risk of hospitalization increased with number of risk factors present at baseline: 38% with zero factors, 57% with one factor, 70% with two or three factors, and 85% with four or five factors (P_trend<.001). CONCLUSION: In a community‐dwelling population with generally mild AD, hospitalization is frequent, occurring in two‐thirds of participants over a median follow‐up time of 3 years. With these results, clinicians may be able to identify dementia patients at high risk for hospitalization.     

Early Diagnosis of Alzheimer's Disease: Clinical and Economic Benefits

An estimated four million individuals in the United States have Alzheimer's disease (AD). This number is expected to more than triple by mid-century. Primary care physicians have a key role in evaluating older patients for early signs of dementia and in initiating treatment that can significantly retard its progression over the maximum period of time. That role and its challenges will inevitably grow along with the expected increase in the population aged 65 and older. The tendency for physicians to dismiss memory complaints as normal aging must be replaced by awareness of the need to assess and possibly intervene. Early intervention is the optimal strategy, not only because the patient's level of function will be preserved for a longer period, but also because community-dwelling patients with AD incur less societal cost than those who require long-term institutional placement. Institutionalization contributes heavily to the annual cost of care for AD in the United States, which is estimated to be $100 billion annually.     

Misdiagnosis of Alzheimer's Disease: Case Studies in Capacity Assessment

The intense focus on Alzheimer's disease has led even experienced practitioners to misdiagnose older adults' cognitive impairment as Alzheimer's. The impact of misdiagnosis may be greatest in cases of capacity, especially conservatorship and testamentary capacity. Two case examples are presented, with an emphasis on diagnostic issues and the importance of accurate diagnosis in light of increasing cases of cognitive dysfunction in older adults. In the first case, issues of delirium and frailty were misdiagnosed as Alzheimer's disease, while in the second case, overreliance on family report and a lack of cultural competency caused a woman with mild cognitive impairment (executive functioning type) to be diagnosed with moderate Alzheimer's disease. As the older adult population grows, clinical gerontologists will continue to be called on to assess capacity, and accurate diagnosis is essential for accurate assessment.     

Differentiating Dementia with Lewy Bodies from Alzheimer's Disease Using the Fall Risk Evaluation Questionnaire

Objective Dementia with Lewy bodies (DLB) is the second-most common form of neurodegenerative dementia after Alzheimer''s disease (AD). Falls are a vital prognostic factor in patients with dementia and are a characteristic feature of DLB. This study investigated the screening potential of the fall risk evaluation for DLB and compared it with that of AD to facilitate an accurate diagnosis. Methods We enrolled patients diagnosed with DLB (n=410) and AD (n=2,683) and categorized the participants into 3 groups depending on their physical ability, age, cognitive function, and fall events. Using the Fall Risk Index-21 (FRI-21) questionnaire, we evaluated and comparatively analyzed the fall risk between DLB and AD patients in three defined groups of participants. Results The FRI-21 score was significantly higher in DLB patients than in AD patients in every group. Using this score, we were able to distinguish between DLB and AD patients in each group. Among the three groups, the group with a young age, relatively mild cognitive dysfunction, and no fall events exhibited the best specificity for DLB (0.895). Conclusions The FRI-21 is a useful tool for screening for DLB and differentiating it from AD. This questionnaire can be used at a relatively early stage of the disease in young patients with mild cognitive dysfunction and no history of falling. These preliminary results need to be validated in an interventional study to evaluate the effectiveness of rehabilitative measures and daily environmental changes carried out to prevent falls using this tool.     

Spaced-Retrieval with Probable Alzheimer's

Abstract

Four older adults with probable Alzheimer's disease (AD) were trained to recall everyday objects using the spaced-retrieval technique. Two persons who had participated in a previous spaced-retrieval training program were retested here to provide new evidence on the long-term effectiveness of the training. Two others who had not been tested previously served as controls. Spaced-retrieval training consisted of six-hour-long sessions given on alternate days over a two-week period. On each trial, participants selected a designated object from an array of items at increasingly longer retention intervals. All participants showed positive effects of spaced-retrieval training across sessions, as reflected in fewer errors per trial and longer retention duration across sessions. There was little evidence of long-term effects of spaced-retrieval training in that the original and control participants performed comparably. Implications of these results for the long-term maintenance of memory training programs are discussed.