The APOE-E4 allele and the risk of functional decline in a community sample of African American and white older adults

BACKGROUND

Given previous findings of adverse health outcomes associated with the E4 allele, data from a biracial community sample of older adults were used to determine whether functional decline is associated with the apolipoprotein E (APOE) E4 allele.

METHODS

In 1986, a stratified random household sample of community residents 65 years of age and older (n = 4162) formed the Duke Established Populations for Epidemiologic Studies of the Elderly. Of those available 6 years later, 78.4% (n = 1999) were genotyped, providing "baseline" data at this time. The available survivors (n = 1529) provided longitudinal data 4 years later. Using longitudinal data from this sample, a combination of measures assessing self-care capability, instrumental activities of daily living (IADL), and mobility was obtained at baseline and 4 years later (n = 1529) to determine the extent to which the E4 allele affected change in functional status. Functional status was assessed using items from a modified Katz Activities of Daily Living (ADL) Scale, the Older American Resources and Services IADL scale, and the Rosow-Breslau physical health scale. Control measures included demographic characteristics, depression, health status, arthritis, and cognitive status. APOE was coded as E4 present versus absent.

RESULTS

APOE E4 was not associated with decline in functional status in either bivariate or multivariate analyses as a main effect. There were, however, statistically significant interactions of the E4 allele with gender and baseline functional status, with greater functional decline in women with the E4 allele, whereas those with poorer baseline functioning who had the E4 allele were less likely to decline. No significant racial differences were found.

CONCLUSIONS

Despite the documented association of the E4 allele of APOE with adverse health outcomes, the E4 allele was not associated with a decline in functional status as a main effect. Interactions of E4 with gender (being female) and baseline functional status, however, did predict functional decline.

Use and cost of outpatient visits of AD patients: CERAD XXII

OBJECTIVE

To determine the probability, frequency, and cost of outpatient visits of patients with AD in the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) as a function of stage of dementia and institutional status.

METHODS

Clinical information on 388 patients with AD enrolled in CERAD who had no serious comorbidities at baseline and for whom the stage of disease and institutional status were known, were linked to Health Care Financing Administration Physician/Supplier and Outpatient Standard Analytic (institutional outpatient) files for 1991 through 1995. None was registered in a health maintenance organization. Repeated measures regression models were used to examine the relationship of stage of disease to probability, frequency, and cost of outpatient visits for institutionalized and noninstitutionalized patients, with demographic characteristics and calendar time controlled.

RESULTS

The annual proportion of patients with AD and a Medicare-reimbursed outpatient visit ranged from 81% to 95% and was not related to stage of dementia or institutional status. Among those with at least one outpatient visit, however, those living at home had fewer visits than did those in institutions, but their number of visits increased as dementia worsened. Those in institutions had a larger number of outpatient visits, but these did not vary significantly by stage of dementia. Neither location of residence nor stage affected the cost of outpatient visits.

CONCLUSION

Among those with an outpatient visit, the frequency of visits and their relationship to stage of disease depends on institutional status.

Use and cost of hospitalization of patients with AD by stage and living arrangement: CERAD XXI

OBJECTIVE

To determine the probability, frequency, length of stay, and Medicare costs of hospitalization of institutionalized and noninstitutionalized patients with AD at various stages of dementia.

METHODS

The authors analyzed the 1991 to 1995 Medicare records of 420 CERAD patients with AD, a group which, at entry, had no serious comorbidities. They were geographically distributed across the United States and observed for a median of 2.5 years. Repeated measures logistic regression and generalized estimating equations were used to model the probability of hospitalization. Among those hospitalized, the general linear mixed model was used to determine number of admissions, length of stay, and Medicare cost. Demographic characteristics and calendar date were controlled in all analyses.

RESULTS

As dementia worsened, the probability of hospitalization increased among patients living at home, but decreased among those who were institutionalized. Number of admissions, length of stay, and cost also decreased significantly as stage worsened among the institutionalized patients, but the stage of dementia had no effect in non-institutionalized patients.

CONCLUSION

The hospitalization experience of patients with AD living at home differs from that of patients with AD living in institutions. Residential setting appears to be an important determinant of hospitalization in patients with AD.

Frequency and duration of hospitalization of patients with AD based on Medicare data: CERAD XX

Medicare records on 477 Consortium to Establish a Registry for Alzheimer's Disease patients with AD for 1991 through 1995 showed a hospitalization rate of 0.37/person-year with a length of stay of 3.7 days/ person-year (average of 10 days/hospitalization). Unmarried and less-educated patients with AD were admitted to the hospital more frequently, and, along with black patients, had a longer length of stay. Frequency and duration of hospitalization were greater in the patients with AD than in Medicare beneficiaries in general, but the rate of diagnostic/therapeutic procedures was lower.

Predictors of time to institutionalization of patients with Alzheimer's disease: the CERAD experience, part XVII

We studied the time to institutionalization (or death as the first event) in 727 white patients with Alzheimer's disease (AD) enrolled in the Consortium to Establish a Registry for Alzheimer's disease (CERAD). At the time of analysis, 417 patients had been admitted to nursing homes and 32 others had died without previous institutionalization. The major predictors of time to first event were sex, age, marital status (men only), and severity of dementia at entry into the study, as measured by activities of daily living, the Mini-Mental State Examination, and the Clinical Dementia Rating scale. The overall median time from enrollment in the study to first event was 3.1 years. For unmarried men, the median time was significantly less (2.1 years) than for either married men or for married or unmarried women, all of whom had medians greater than 3 years. In an analysis of survival time following institutionalization, we found that men survived a median of 2.1 years, compared with 4.5 years for women. This nationwide study of AD largely confirms earlier studies that reported on smaller numbers of cases from local catchment areas and included patients with various types of dementia.

Weight change in Alzheimer's disease

PURPOSE

To determine the natural history of weight change and the occurrence of clinically significant weight loss in subjects with Alzheimer's disease (AD).

PATIENTS AND METHODS

Subjects with AD and cognitively normal older controls were recruited from 21 U.S. university medical centers that were participating in the Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Annual assessments were performed. Subjects with AD (n = 362) and controls (n = 317) with two or more weight measurements taken a year or more apart were included in this analysis. The average period of follow-up was > 2 years for both subjects with AD and controls. Four variables describing different aspects of weight change were defined: >/= 5% weigh loss, percent weight change/year, maximum percent weight loss over 1 year, and standard deviation of measurements/subject.

RESULTS

Nearly twice as many subjects with AD experienced a weight loss of 5% or more when compared with controls (men P = .003 women P = .001). Surprisingly, a weight gain of 5% or more was also more common among AD cases. Overall, there was a tendency toward weight loss for both subjects with AD and controls, as measured by percent weight change/year. When other possible causes of weight loss were controlled using a multivariate model, a diagnosis of AD remained a significant predictor of >/= 5% weigh loss (P << .001), maximum percent weight loss over 1 year (P << .001), and standard deviation of measurements/subject (P << .001). A trend toward significance was noted for percent weight change/year (P = .07). Other than AD, very few of the possible confounders of this association remained significant predictors of weight change. In bivariate analysis, the severity of AD at entry correlated with percent weight change/year and standard deviation of measurements/subject. Additionally, the functional status of subjects with AD correlated with all four measures of weight change.

CONCLUSION

Clinically important weight loss occurs more frequently among patients with AD than among cognitively normal control subjects. Instances of weight gain, periods of acute weight loss, and greater fluctuations in weight suggest that the natural history of weight change in AD may be characterized by dysfunction in body weight regulation. Further analysis is warranted regarding the relationship of severity of dementia, functional status, and other specific aspects of AD to weight change.

The consortium to establish a registry for Alzheimer's disease (CERAD). Part XIV: Demographic and clinical predictors of survival in patients with Alzheimer's disease

We made follow-up observations on 1,036 Consortium to Establish a Registry for Alzheimer's Disease (CERAD) patients with Alzheimer's disease (AD) enrolled in 21 university medical centers in the United States. Evaluations were scheduled annually for as long as 7 years; at the time of analysis, there were 332 deaths. The median duration of survival from time of entry into CERAD was 5.9 years (95% CI; 5.6 to 6.4 years). Factors independently affecting survival were sex, age, and severity of dementia as measured by the Clinical Dementia Rating scale and the Blessed Scale for activities of daily living. The median survival after entry was 5.7 years for men, compared with 7.2 years for women. For men age 70, 75, and 80 years, median survival times were 6.5, 5.5, and 4.4 years, values notably less than those for the general population. Neither race, education, nor marital status significantly affect survival. This large nationwide study confirms the fact that AD is associated with shorter survival, particularly in men, subjects age 70 or older, patients with greater impairment in daily activities of living, and those with more severe dementia.

Clinical and neuropsychological differences between patients with earlier and later onset of Alzheimer's disease: A CERAD analysis, Part XII

To determine whether the age of the onset of Alzheimer's disease (AD) is related to the expression and rate of decline of this disorder, we examined the clinical and neuropsychological performance of 421 patients entered into the Consortium to Establish a Registry for Alzheimer's Disease and followed annually for up to 4 years. Statistical analyses were based on multivariable logistic regression analysis for dichotomous clinical measures and multivariable linear regression analysis for psychometric measures. All analyses examined the effect of age after controlling for gender, education, and stage of dementia. Clinical information obtained on entry into the study indicated that younger patients performed more poorly on measures of language and concentration, and older patients performed more poorly on measures of memory and orientation. On neuropsychological measures at entry, younger patients, performed more poorly on praxis and had significantly higher scores of confrontation naming. Younger age predicted a significantly faster rate of progression for all neuropsychological measures. These findings support the concept of age-related clinical subtypes of AD.

Neuropsychological test performance in African-American and white patients with Alzheimer's disease

Little information exists on the performance of black versus white patients with Alzheimer's disease on neuropsychological tests for dementia. In this study, we compared performance on the CERAD (Consortium to Establish a Registry for Alzheimer's Disease) neuropsychological battery between white (n = 830) and black (n = 158) patients with Alzheimer's disease enrolled in the CERAD study at 23 university medical centers in the United States. The black patients were older, had fewer years of formal education, and were more impaired in their activities of daily living than were the white patients. After controlling for these characteristics and for duration of the disease and severity of dementia, there were differences in the performance of black and white patients on several of the cognitive measures. Black patients scored lower than whites on tests of visual naming and constructional praxis and on the Mini-Mental State Examination. There were no statistical differences in performance on tests of fluency and word list memory. These findings suggest that cultural or experiential differences may modify performance on specific neuropsychological tests. These factors, in addition to age and educational background, should be considered when interpreting performance on neuropsychological tests in elderly black patients with dementia.

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Part IX. A prospective cliniconeuropathologic study of Parkinson's features in Alzheimer's disease

Although extrapyramidal signs such as rigidity, bradykinesia, and postural impairment frequently occur in patients with Alzheimer's disease (AD), the correlation of these parkinsonian manifestations with the neuropathologic changes of Parkinson's disease (PD) has not been well established. Previous clinicopathologic studies addressing this issue have been largely retrospective or have consisted of relatively small numbers of cases. We examined the neuropathologic correlates of clinical parkinsonism in 78 cases with autopsy-confirmed AD prospectively enrolled in the Consortium to Establish a Registry for Alzheimer's Disease. Sixteen (20.5%) of the 78 AD cases showed concomitant PD pathology (AD/PD) as evidenced by the presence of nigral degeneration and Lewy bodies at any site. There were neocortical Lewy bodies in eight of these 16 cases. Two or more clinical manifestations of extrapyramidal dysfunction were present in eight (50.0%) of the 16 cases of AD/PD versus 11 (17.7%) of the 62 cases of AD alone (p < 0.01). Although semiquantitative ratings of the frequency of neuritic plaques showed no differences between the two groups, neurofibrillary tangles in the AD/PD group were less frequent in the midfrontal (p < 0.001) and superior temporal cortex (p < 0.05). These findings support previous reports that AD/PD cases are more likely to manifest extrapyramidal dysfunction and show plaque predominance at autopsy.

Health services access and use among older adults in North Carolina: urban vs rural residents

OBJECTIVES

This study compared health service use and satisfaction with health care among older adults living in urban vs rural counties in North Carolina.

METHODS

A stratified random sample of 4162 residents of one urban and four rural counties of North Carolina was surveyed to determine urban/rural variation in inpatient and outpatient health service use, continuity of care and satisfaction with care, and barriers (transportation, cost) to care.

RESULTS

Inpatient and outpatient service use did not vary by residence in controlled analyses. Continuity of care was more frequent in rural counties. Transportation was not perceived as a barrier to health care more frequently in rural than in urban counties, but cost was a greater barrier to care among rural elderly people.

CONCLUSIONS

In this sample, older persons living in rural counties within reasonable driving distance of urban counties with major medical centers used health services as frequently and were as satisfied with their health care as persons in urban counties. Cost of care, however, was a significant and persistent barrier among rural elderly people, despite Medicare coverage.

The Behavior Rating Scale for Dementia of the Consortium to Establish a Registry for Alzheimer's Disease. The Behavioral Pathology Committee of the Consortium to Establish a Registry for Alzheimer's Disease

OBJECTIVE

The purpose of the study was to develop a standardized instrument, the Behavior Rating Scale for Dementia, for rating psychopathology in patients with probable Alzheimer's disease and to conduct a multicenter pilot study of this instrument.

METHOD

The rating scale was developed collaboratively on the basis of clinical experience and existing instruments. Items were scaled according to frequency of psychopathology and were administered to an informant who was familiar with the subject. The scale was administered in a standardized manner by trained examiners who had met predetermined certification standards. The study group consisted of 303 subjects with probable Alzheimer's disease who had undergone standardized clinical evaluations by the Consortium to Establish a Registry for Alzheimer's Disease.

RESULTS

Subjects had an average of 15 problems rated as present in the preceding month. Wide variability in the nature of disturbances was found, with a number of items rated as present since the illness began but not in the past month. Interrater agreement was high. Factor analysis suggested eight preliminary factors that mapped onto clinically relevant domains: depressive features, psychotic features, defective self-regulation, irritability/agitation, vegetative features, apathy, aggression, and affective lability.

CONCLUSIONS

The Behavior Rating Scale for Dementia provides a standardized, reliable measure that can be administered to caregivers of demented subjects. On the basis of the present study, the scale has been revised slightly. After additional studies in progress, the Behavior Rating Scale for Dementia will be available for general use in assessing a wide range of psychopathology in dementia.

Translation of clinical and neuropsychological instruments into French: the CERAD experience

The increasing number of international and epidemiological studies of Alzheimer's disease points to the need for linguistically equivalent translations of measures for identifying the presence, types, and severity of dementia in cross-cultural populations. In translating the CERAD (Consortium to Establish a Registry for Alzheimer's Disease) neuropsychological instruments into French, several linguistic issues have emerged such as semantic, phonetic, and word-frequency equivalences. In verbal memory tests, these problems, though minor in appearance, can be major pitfalls in studies comparing cognitive function in populations differing in language. Description of the translation procedure and examples of problems encountered are presented, with measures taken to resolve them.

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Part VI. Family history assessment: a multicenter study of first-degree relatives of Alzheimer's disease probands and nondemented spouse controls

Although familial factors in Alzheimer's disease (AD) are well established, uniform family-history assessment in genetic and epidemiologic studies of AD is needed to reconcile the divergent estimates of the cumulative risk of this illness among relatives of AD probands. To answer the need, the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) has developed a standardized Family History Assessment of AD to identify the presence of AD, Parkinson's disease (PD), and Down's syndrome (DS) in family members. This paper describes the use of this new assessment instrument in 118 patients with AD (estimated mean age at onset [+/- SD] = 64.5 +/- 7.7 years) and their nondemented spouses who were enrolled in 11 different CERAD sites in the U.S. The first-degree relatives of the probands with AD had a significantly greater cumulative risk (p < 0.005) of AD or primary progressive dementia (24.8%) than did the relatives of spouse controls (15.2%). Furthermore, the cumulative risk for this disorder among female relatives of probands was significantly greater than that among male relatives. There were no differences between the families of probands and controls for the numbers of affected first-degree relatives with PD or DS. This is the first reported multicenter family-history study of AD, and it supports earlier reports of familial factors in AD and indicates a higher risk to female relatives of AD probands. The CERAD Family History Assessment instrument may be useful for further multicenter and epidemiologic studies designed to delineate familial factors associated with AD.

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Part V. A normative study of the neuropsychological battery

The neuropsychological tests developed for the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) are currently used to measure cognitive impairments of Alzheimer's disease (AD) in clinical investigations of this disorder. This report presents the normative information for the CERAD battery, obtained in a large sample (n = 413) of control subjects (ages 50 to 89) who were enrolled in 23 university medical centers in the United States participating in the CERAD study from 1987 to 1992. We compared separately the performance of subjects with high (> or = 12) and low (< 12) years of formal education. For many of the individual cognitive measures in the highly educated group, we observed significant age and gender effects. Only the praxis measure showed a significant age effect in the low-education group. Delayed recall, when adjusted for amount of material acquired (savings), was relatively unaffected by age, gender, and level of education. Our findings suggest that the savings scores, in particular, may be useful in distinguishing between AD and normal aging.

Association of education with incidence of cognitive impairment in three established populations for epidemiologic studies of the elderly

We analyzed the association of education, occupation, and sex with incidence of cognitive impairment using data from three communities in the Established Populations for Epidemiologic Studies of the Elderly (EPESE) projects (New Haven, East Boston, and Iowa). Participants were initially interviewed in 1981-1983, with follow-up 3 and 6 years later. Incident cognitive impairment was defined on the basis of either: (1) increase in the number of errors in Short Portable Mental Status Questionnaire (SPMSQ) (i.e. from a baseline level below the cutoff value to a score above the cutoff), or (2) inability to respond to interview questions at a follow-up contact (requiring a proxy informant), or (3) death with a recorded diagnosis of a dementing illness. In multiple logistic regression models, the major factors predicting the development of cognitive impairment were advanced age, any errors on baseline SPMSQ, 8 or fewer years of education, and occupation. Education and occupation remained significant predictors after controlling for age, site, sex, stroke, and baseline SPMSQ score.

The consortium to establish a registry for Alzheimer's disease (CERAD). Part IV. Rates of cognitive change in the longitudinal assessment of probable Alzheimer's disease

Reliable information on rate of progression of cognitive impairment in probable Alzheimer's disease (AD) is important for evaluating possible beneficial effects of therapeutic agents and in planning long-term care for patients with this chronic illness. However, wide variability exists in published rates of change for psychometric measures of the dementing process, and there is need for an accurate analysis of large numbers of persons with the disorder studied over long periods. Utilizing the large, well-characterized sample of the Consortium to Establish a Registry for Alzheimer's Disease and employing a least squares regression method to adjust for different levels of impairment and periods of observation, we report rates of change on the Short Blessed Test, Mini-Mental State Examination, Blessed Dementia Scale, Clinical Dementia Rating, and other cognitive measures in 430 patients with probable AD (mean age at entry = 70.9 +/- 8.0 SD years) studied for up to 4 years. We found that rate-of-change determinations are less reliable when the observation period is 1 year or less, that dementia progression may be nonlinear when described by certain measures, and that simple change scores do not accurately characterize the rate of decline. We also found that rate of progression in AD is determined by the severity of cognitive impairment: the less severe the dementia, the slower the rate of decline.

Risk due to inactivity in physically capable older adults

OBJECTIVES

This study examined the association between recreational physical activity among physically capable older adults and functional status, incidence of selected chronic conditions, and mortality over 3 and 6 years.

METHODS

Data are from three sites of the Established Populations for Epidemiologic Studies of the Elderly.

RESULTS

A high level of recreational physical activity reduced the likelihood of mortality over both 3 and 6 years. Moderate to high activity reduced the risk of physical impairments over 3 years; this effect diminishes after 6 years. A consistent relationship between activity and new myocardial infarction or stroke or the incidence of diabetes or angina was not found after 3 or 6 years.

CONCLUSIONS

Findings suggest that physical activity offers benefits to physically capable older adults, primarily in reducing the risk of functional decline and mortality. Future work must use more objective and quantifiable measures of activity and assess changes in activity levels over time.

Estimated prevalence of dementia among elderly black and white community residents

A stratified random sample of 83 black and 81 white community residents aged 65 years and older in a five-county area in the Piedmont region of North Carolina was evaluated for dementia, using the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, and the National Institute of Neurological Disorders and Stroke--Alzheimer's Disease and Related Disorders Association criteria. Of 164 subjects, 26 were found to be demented, resulting in an estimated prevalence rate of dementia in the five-county area of 16% (95% confidence interval, 7.92 to 24.08) for blacks and 3.05% (95% confidence interval, 0 to 6.91) for whites. The estimated prevalence of dementia for white women (2.9%) was similar to that for white men (3.3%), but the rate for black women was distinctly higher than for black men (19.9% and 8.9%, respectively). Blacks were more likely than whites to have a history of stroke, hypertension, and other chronic disorders that might have contributed to the development of dementia. Apart from differences in rates of institutionalization, no other relevant factors were identified that might explain the difference in the prevalence of dementia in these black and white community residents.

Sensitivity and specificity of standardized screens of cognitive impairment and dementia among elderly black and white community residents

Six standardized published measures of cognitive function were evaluated as screens of dementia in a sample of 164 (83 black, 81 white) community residents aged 65 and over selected from the Duke University EPESE (Established Populations for Epidemiologic Studies of the Elderly), a biracial cohort of 4164 residents in a five county area of piedmont North Carolina. Of these 164 persons, 26 were subsequently diagnosed as demented. The weighted data from this sample represent the estimated performance of these measures among elderly blacks and whites in a five county area. The 6 measures evaluated in this study (specificity figures for blacks precede those for whites) were (1) Orientation-Memory-Concentration Test (38%, 79%), (2) Mental Status Questionnaire (71%, 96%), (3) Mini-Mental State (58%, 94%), (4) Storandt et al. Battery (42%, 69%), (5) Iowa Battery (26%, 69%) and (6) Kendrick Cognitive Tests (92%, 97%). All but the Kendrick Cognitive Tests showed substantial sensitivity (90-100%) in detecting the presence of dementia. The specificity of the tests was particularly poor for blacks. The briefer, simpler measures tended to have greater accuracy than the longer and more complex measures. With rare exceptions, the scores obtained on these screens correlated with race and education.

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Part I. Clinical and neuropsychological assessment of Alzheimer's disease

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) has developed brief, comprehensive, and reliable batteries of clinical and neuropsychological tests for assessment of patients with the clinical diagnosis of Alzheimer's disease (AD). We administered these batteries in a standardized manner to more than 350 subjects with a diagnosis of AD and 275 control subjects who were enrolled in a nationwide registry by a consortium of 16 university medical centers. The tests selected for this study measured the primary cognitive manifestations of AD across a range of severity of the disorder, and discriminated between normal subjects and those with mild and moderate dementia. The batteries also detected deterioration of language, memory, praxis, and general intellectual status in subjects returning for reassessment 1 year later. Interrater and test-retest reliabilities were substantial. Long-term observations of this cohort are in progress in an effort to validate the clinical and neuropsychological assessments and to confirm the diagnosis by postmortem examinations. Although information on validation is limited thus far, the CERAD batteries appear to fill a need for a standardized, easily administered, and reliable instrument for evaluating persons with AD in multicenter research studies as well as in clinical practice.

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Part I. Clinical and neuropsychological assessment of Alzheimer's disease

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) has developed brief, comprehensive, and reliable batteries of clinical and neuropsychological tests for assessment of patients with the clinical diagnosis of Alzheimer's disease (AD). We administered these batteries in a standardized manner to more than 350 subjects with a diagnosis of AD and 275 control subjects who were enrolled in a nationwide registry by a consortium of 16 university medical centers. The tests selected for this study measured the primary cognitive manifestations of AD across a range of severity of the disorder, and discriminated between normal subjects and those with mild and moderate dementia. The batteries also detected deterioration of language, memory, praxis, and general intellectual status in subjects returning for reassessment 1 year later. Interrater and test-retest reliabilities were substantial. Long-term observations of this cohort are in progress in an effort to validate the clinical and neuropsychological assessments and to confirm the diagnosis by postmortem examinations. Although information on validation is limited thus far, the CERAD batteries appear to fill a need for a standardized, easily administered, and reliable instrument for evaluating persons with AD in multicenter research studies as well as in clinical practice.