Diagnosis of dementia in a heterogeneous population. A comparison of paradigm-based diagnosis and physician's diagnosis.

Each of 430 subjects received a diagnosis using two independent methods: a test-based quantitative paradigm and a semistructured neurological examination by a physician. The paradigm diagnosis was based on a battery of tests that assessed short- and long-term verbal memory and short-term nonverbal memory, orientation, construction, abstract reasoning, and language. The subjects came from a community in Manhattan County, in New York City, and were characterized by diversity with respect to both ethnicity (29.1% black, 33.4% Hispanic) and educational level (23.5% with 6 or fewer years of education, 25.6% college educated). Based on the paradigm, 10.5% of subjects received diagnoses of dementia, 29.1% of cognitive impairment, and 60.5% of normal. Based on the physician's diagnosis, 9.8% were demented, 21.6% cognitively impaired, and 68.6% normal. There was agreement between the two diagnostic methods for 71.8% of subjects. Diagnostic disagreement (n = 121) was in most cases between normal and cognitively impaired (71.0%) or between cognitively impaired and demented (21.5%). There were only nine cases (7.5%) in which a subject was judged demented by one method and normal by the other. The reliability of each method with respect to the other was moderate (intraclass correlation coefficient, .62), while the reliability of a composite diagnosis based on both methods was much higher (.77). The paradigm was more likely than the physician to give the diagnosis of dementia to patients with low educational levels. The physician's diagnosis was strongly influenced by measures of functioning and by the mental status test administered in the semistructured neurological examination. Race and diagnosis were not related when the effect of education was controlled.(ABSTRACT TRUNCATED AT 250 WORDS)     

Several neuropsychological tests to assist dementia diagnosis in low education elderly population

Objective: ScnsitMty and specificity of several psychometric tests were evaluated to provide practical instruments tor dementia diagnosis in low educational population. Method: A total of 3244 residents aged 55 ycars and over were drawn through a stratified multiple cluster sampling, 62 percent were illiterate or have elementary education. Door to door screening to all participants were conducted in phase 1 using Chinese version of Mini-Mental State Examination (CMMSE), then followed up and identified dementia through a set of diagnostic examination in phase Il . Cases were ascertained by DSM-Ⅳ criteria for dementia. 457 subjects1 had competed more than one of these psychometric tests, including Fuld Object-Memory Evaluation (FOM), Rapid Verbal Retreve(RVR), Block Design (BD), and Digit Span (DS). 145 cases were divided into 3 subgroup, illiterate group (48.28%), elementary education group (26.2 l%), and high education group (25.54%). Result: Specificity of FOM and RVR were more than 94% in all groups while Sensitivity were between 52-78%. Specificity of BD and DS were between 72-85% and 78-98% respectively. Specificity of BD and DS have tendency to increasing while sensitivity of BD and DS declined obviously with increasing of educationievel. Specificity of series test was more than 97% except for BD and DS. Conclusion: Sensitivity and specificity of FOM amd RVR were good in different education group. BD and DS were good in low educational group. So the four psychometric tests were suitable instruments tor low education level population in our country.     

神经心理测验对痴呆诊断的贡献与误区

目的：评价神经心理测验（NPT）对痴呆诊断的作用及局限性。方法：痴呆组270例，非痴呆组617名，进行简易精神状态检查、Fuld物体记忆测验、言语流畅性测验、数字广度测验和积木测验。结果：痴呆和非痴呆组NPT得分差异有显著意义。4个测验特异性高在72％－99％之间，敏感性在22％－90％之间，随文化水平的增高而降低。在筛查的基础上加用NPT，诊断准确性由68％提高到80％－89％。文化、年龄、性别对NPT有显著影响。结论：NPT可提高痴呆诊断的准确性。本组NPT适合于我国低文化老人的痴呆调查，对高文化轻度痴呆应采用更敏感的测验。     

A brief neuropsychological assessment for the differential diagnosis between frontotemporal dementia and Alzheimer's disease

The neuropsychological performance (including measures of language, semantic memory, visual and spatial perception and executive functions) of a group of 14 patients with the clinical diagnosis of probable frontotemporal dementia was compared with that of a group of 14 patients with a clinical diagnosis of probable Alzheimer's disease. The aim was to identify a specific cognitive profile of frontotemporal dementia, which could be used to select a sensitive, short evaluation for the differential diagnosis with Alzheimer's disease. Both groups were severely impaired in most tasks, including those 'frontal lobe' tests which have been suggested to play an important role in differential diagnosis. Significant differences were found only for a minority of tests (oral praxis, visual-spatial perception, and verbal fluency). A logistic regression showed that a shortened testing procedure based on four tests (Rey-Osterreith complex figure test recall, phonemic fluency, oral apraxia, and cube analysis) achieved a 70% sensitivity and 80% specificity for the correct classification of patients in the frontotemporal dementia or Alzheimer's disease group. In conclusion, a brief neuropsychological evaluation including these four tests, as well as other measures sensitive to the frontal impairment, can be useful in the differential diagnosis between the two pathologies, along with the clinical data.     

Prevalence of dementia in an elderly rural population: effects of age, sex, and education.

OBJECTIVES--To estimate the prevalence of dementia in an elderly rural population and to determine the effects of age, sex, and education. METHODS--To obtain prevalence estimates of both cognitive impairment and dementia a door to door two phase population survey was carried out in three rural villages in central Italy. Of 1147 inhabitants older than 64, 968 (84.4%) completed the protocol. RESULTS--The prevalence rates (cases per 100 population over 64) were 8.0 for dementia and 27.3 for cognitive impairment. The prevalence rate for dementia did not differ between men and women (7.9 v 8.2), but increased with age (from 1.1 at age 65-69 to 34.8 at age 90-96). Subjects with less than three years of schooling had a significantly higher prevalence of dementia (14.6; 95% confidence interval (95% CI) 10.2-19.1) than subjects with three or more years of schooling (5.9; 95% CI 4.2-7.7). At the multivariate logistic analysis, the risk related with a low level of education was still present after adjustment for age and sex (OR = 2.0; 95% CI 1.2-3.3). Alzheimer's disease was diagnosed in 64% of the 78 demented patients, vascular dementia in 27%, and other dementing diseases in 9%. CONCLUSIONS--In both Alzheimer and vascular dementia subtypes, the prevalence rates did not differ between men and women, but increased with age and were higher in subjects with a low level of education.     

Effectiveness of a clinical pathway for the diagnosis and treatment of dementia and for the education of families

AIMS: Clinical pathways (CPs) are rarely used in the treatment of dementia. We established a CP for a series of medical practices (diagnosis, treatment, establishment of a care system, and caregiver education) for patients with dementia hospitalized for a three-week period, and evaluated its usefulness. METHODS: The length of hospital stay and hospital costs were compared between 23 consecutive patients with dementia hospitalized and treated using a CP and 20 controls treated by conventional medical practice without using a CP in a special ward for dementia patients. In the CP group, at the time of discharge, primary caregivers, physicians, and nurses were given a questionnaire to obtain their comments about the impression of treatment with the CP. RESULTS: The questionnaire survey indicated that the CP deepened the caregiver's understanding of the sequence of medical practices for the inpatient, the disorders of the inpatient, the treatment methods, and the methods for coping with the disorder. The CP was also useful for facilitating inpatient medical practice and promoting the establishment of a care system after discharge. The use of the CP significantly shortened the length of hospital stay and decreased hospital costs during hospitalization but increased the amount of work per day and made the medical staff feel that their freedom to choose medical procedures had been restricted. CONCLUSIONS: The CP was useful for execution of inpatient medical practices for patients with dementia.     

Simple standardised neuropsychological assessments aid in the differential diagnosis of dementia with Lewy bodies from Alzheimer's disease and vascular dementia

Consecutive patients from a dementia case register received a standardised evaluation which incorporated a neuropsychological assessment with the Cambridge Assessment for disorders in the elderly (CAMCOG). Operationalised clinical diagnoses were made (consensus criteria for dementia with Lewy bodies, DLB; NINCDS- ADRDA for Alzheimer's disease, AD, NINCDS AIRENS for vascular dementia, VaD). Two-hundred and twenty-eight patients were studied (DLB 54, AD102, VaD 72). DLB patients had significantly better performance on recent memory than AD patients, but more impaired visuospatial praxis. DLB patients also had significantly better recent memory than those with VaD. Optimal cut-off points for the recent memory:praxis ratio achieved good discrimination between DLB and both other dementias.     

Vascular dementia and Alzheimer's disease: the unsolved problem of clinical and neuropsychological differential diagnosis

The definition of clinical criteria for differential diagnosis of Vascular Dementia (VaD) and Alzheimer's disease (AD) remains controversial. A large group of patients selected was affected by chronic cerebrovascular disease classified as VaD or not (VND), according to DSM IV criteria. Neuropsychological performances of VaD patients were compared with a group of patients affected by probable AD, matched for age, education, and severity of disease. The comparison of performances did not reach statistical significance in single neuropsychological tasks. The results suggest that neuropsychological examination might not clearly differentiate between VaD and AD patients; the similar pattern of cognitive impairment is probably indicative of several common pathogenetic mechanisms.     

Frontotemporal dementia, semantic dementia, and Alzheimer's disease: the contribution of standard neuropsychological tests to differential diagnosis

CERAD-NAB (Consortium to Establish a Registry for Alzheimer's Disease-Neuropsychological Assessment Battery) data were compared between 51 patients with frontotemporal dementia, 13 with semantic dementia, and 69 with Alzheimer's disease. There were statistically significant differences between the 3 groups. Compared with patients with Alzheimer's disease, patients with frontotemporal dementia were more impaired on Animal Fluency but not on any other CERAD-NAB subtest. Patients with semantic dementia performed worse in Animal Fluency and Boston Naming Test compared with frontotemporal dementia and Alzheimer's disease. Multiple logistic regression analysis revealed that in the differentiation between frontotemporal dementia and Alzheimer's disease, the combination of Animal Fluency and Boston Naming Test correctly classified 90.5% of patients. In segregating semantic dementia and Alzheimer's disease, the combination of Boston Naming Test and Mini Mental State Examination resulted in a correct classification of 96.3%. These findings demonstrate that the Mini Mental State Examination and the language subtests of the CERAD-NAB are valuable clinical instruments for the differential diagnosis between early frontotemporal dementia, semantic dementia, and Alzheimer's disease.     

Prediction of all-cause dementia using neuropsychological tests within 10 and 5 years of diagnosis in a community-based sample

While neuropsychological tests have been identified for the early prediction of Alzheimer's disease, this has not been established for prediction of all-cause dementia. This would be helpful for clinicians concerned about the risk of progression to dementia in patients who may present with a variety of medical and neurological conditions. We wanted to determine whether neuropsychological tests could accurately predict incident dementia within 10 and five years of diagnosis in a community-based sample. The Canadian Study of Health and Aging was conducted in three waves over a 10-year period (1991-2002). We studied 1472 non-demented participants who completed neuropsychological testing in 1991 and received a diagnostic assessment for dementia in 2001 (n = 284). We also studied 1231 non-demented participants who completed neuropsychological testing in 1996 and received a diagnostic assessment in 2001 (n = 634). Diagnosticians were blinded to performance on the predictive tests. Age, education, and sex were included as covariates in all regression analysis. Ten-year prediction: 2 tests, Rey Auditory Verbal Learning Test (RAVLT) short delayed verbal recall and Wechsler Adult Intelligence Test Revised (WAIS-R) Digit Symbol, were significant predictors of dementia (sensitivity = 78%, specificity = 72%, positive likelihood ratio = 2.81). Five-year prediction: 4 tests, Wechsler Memory Scale Information, RAVLT short delayed verbal recall, animal fluency, and WAIS-R Digit Symbol, significantly predicted incident dementia (sensitivity = 75%, specificity = 74%, positive likelihood ratio = 2.90). Regression models were supported with bootstrapping estimates. Neuropsychological tests can accurately predict progression to all-cause dementia within 10 years of diagnosis in a large community-based sample of non-demented participants.     

White-matter hyperintensity and neuropsychological functions in dementia and healthy aging.

The relationship between quantitative measurements of brain white-matter hyperintensity (WMH), assessed by magnetic resonance imaging and neuropsychological functions, was explored in demented patients and healthy aged individuals with and without WMH in 12 brain regions. The prevalence of WMH was significantly higher in vascular dementia compared with Alzheimer's disease, especially in posterior periventricular regions. Results showed no difference in any neuropsychological measurement between healthy aged adults with and without WMH. The demented patients with WMH were more impaired in tests of visuoconstruction, attention, finger-motor speed, and latency of tactile identification of objects compared with patients without WMH. These impairments were related mainly to posterior periventricular WMH. There was no relationship between WMH and global cognitive functioning in the demented patients. The degree of WMH was related to age and blood pressure. The data suggest that specific regional WMH may result in specific neuropsychological impairments.     

Cognitive Assessment and Reference Diagnosis System: development of a neuropsychological and clinical examination for clinic and population use

Background: Recent therapeutic advances to delay the progression of dementia have renewed calls to improve the early detection and management of individuals with dementia. A new computerized neuropsychological interview and clinical examination, the Cognitive Assessment and Reference Diagnosis System (CARDS) was developed to incorporate in a single instrument all the information required to make an accurate clinical diagnosis of dementia (its subtype, depression and delirium), to present reference diagnoses following the completion of tests and to detect early dementia. This study aims to verify the validity and reliability of CARDS. Methods: The CARDS was administered to 70 dementia patients (51 Alzheimer's disease, 19 vascular dementia) and 34 healthy (control) subjects. Three aspects of reliability (internal consistency reliability, inter‐rater and test–retest reliability) were tested. Correlations with the Alzheimer's Disease Assessment Scale, Korean version (ADAS‐K), the Cambridge Cognitive Examination, Korean version (CAMCOG‐K) and the Mini‐Mental State Examination, Korean version (MMSE‐K) were used to estimate the concurrent validity of CARDS. To evaluate the sensitivity of CARDS, mean scores from CARDS, ADAS‐K, CAMCOG‐K and MMSE‐K were compared between dementia patients and control subjects. Results: The CARDS demonstrated high levels of reliability. Mean CARDS scores for dementia patients were significantly different from the control group (P < 0.001). Furthermore, CARDS was significantly correlated with other tests and scales (P < 0.01). Conclusion: We demonstrated that CARDS is a reliable and valid instrument not only for dementia diagnosis, but also for the evaluation of impaired cognitive domains. A regression equation, derived from nationwide population surveys for norm data from CARDS, will be applied for individualized cutoff scores of five domains of dementia to eliminate the influence of age, sex and educational attainment on test scores.     

Sharpening the boundaries of Parkinson-associated dementia: recommendation for a neuropsychological diagnostic procedure

Older adults suffering from Parkinson’s disease (PD) frequently present with an additional form of severe neurodegenerative and/or vascular pathology. Findings of differential clinical manifestations of cognitive impairment, depending on presence and nature of such coexisting brain pathology, raise the question for neuropsychological procedures that are capable not only of distinguishing between non-demented PD patients and patients with Parkinson-associated dementia (PDD), but also of detecting other types of cognitive decline, most likely Alzheimer’s disease (AD) or vascular dementia (VD), superimposing PD. The aim of this article is to review the literature on neuropsychological processes at risk in developing PDD, to introduce comorbid causes of cognitive decline in the presence of PD, to discuss the scope of the “cortical versus subcortical dementia”-concept in view of its capability of differentiating dementias, and to scrutinize existing diagnostic criteria concerning the toleration of comorbidity. Additionally, we derive an evidence-based neuropsychological diagnostic procedure for assessing PDD under special consideration of these comorbid aspects.     

Interrater reliability of the INTERMED in a heterogeneous somatic population.

The INTERMED has been developed to score biopsychosocial case complexity and care needs. In this study, the interrater reliability of the INTERMED was assessed by calculating the agreement of two independent raters, based on the same information. Forty-three in- and outpatients with varying somatic complaints were double scored by a psychologist and a psychiatric C-L nurse. Correlations between total scores of the two raters were ranging from 0.91-0.96. On item level, in 83% there were no differences between the raters, in 16% there was a 1-point difference and in 1% a 2-point difference. Based on a cut-off score of 20/21, a constant k of 0.85 was found. We concluded that the two experienced raters had a high agreement, and that after sufficient training the INTERMED can be reliably scored. Its utility in improving health care delivery for patients with complex biopsychosocial care needs still has to be demonstrated.     

Population-based dementia screening program in Kuopio: the effect of education, age, and sex on brief neuropsychological tests.

A neuropsychological screening battery including the Mini-Mental State Examination and four other brief cognitive tests (Russell's Adaptation of the Visual Reproduction Test, Trail Making Test, Verbal Fluency Tests on letters and category, and the Buschke Selective Reminding Test) was administered to a randomly selected population sample of 403 subjects aged 68 to 77 years to evaluate the effect of education, age, and sex on test scores. The difference in neuropsychological screening tests between various education groups (3 years or less, 4 to 6 years, 7 years or more) was statistically highly significant, even after the adjustment for the effect of age. The subscores and total scores were lowest in the minimal education group on every neuropsychological test. Education correlated more strongly than age with all neuropsychological test scores and subscores. The effect of sex on test results was seen only in some subscores of brief neuropsychological tests but not in a single item of the Mini-Mental State Examination. On the basis of our results, the effects of education, age, and sex have to be evaluated before using brief neuropsychological tests in population-based dementia screening.     

Clock drawing errors in dementia: neuropsychological and neuroanatomical considerations.

OBJECTIVES: A clock drawing test scoring system is presented to explore the neuropsychological/neuroanatomic components underlying clock drawing in patients initially diagnosed with Alzheimer disease, ischemic vascular dementia associated with white matter alterations, and Parkinson disease. METHODS: Fourteen clock drawing test errors were scored to create 4 clock drawing test subscales that assess different underlying cognitive operations. RESULTS: In the command condition, errors on the Time subscale were correlated with impairment on executive control measures. In the copy condition, errors on the Perseveration/Pull to Stimulus subscale was also correlated with executive control measures. Patients presenting with mild (low) magnetic resonance imaging white matter alterations, significant (high) white matter alterations, and Parkinson disease were compared. In the command condition, the low white matter alterations group made fewer total errors than the Parkinson disease group. In the copy condition, the low white matter alterations group made fewer errors on the Time, Spatial Layout, and Perseveration/Pull to Stimulus clock drawing test subscales than the high white matter alterations or Parkinson disease groups. Few differences were noted between the high white matter alterations and Parkinson disease groups. DISCUSSION: Our data suggest that heavy demands on executive control associated with the interruption of large-scale cortical-subcortical neural networks underlie impairment in clock drawing in mild dementia.     

Patterns of neuropsychological impairment in mild dementia: a comparison between Alzheimer's disease and multi-infarct dementia

The objective was to investigate the clinical and psychometric differences between patients with dementia of Alzheimer type (DAT) and patients with multi-infarct dementia (MID), matched for age, sex, education, and severity. Sixteen patients with DAT, 16 patients with MID, and 30 healthy individuals, were drawn from a longitudinal study on aging and dementia. Subjects with medical or previous mental disorders were excluded. DAT and controls with focal brain abnormalities on magnetic resonance imaging (MRI) were excluded. Diagnosis of dementia was carried out according to DSM-III-R criteria. Dementia severity was staged using the Clinical Dementia Rating (CDR) scale, and only patients with a score of 0.5-1 on CDR were studied. The main outcome measures were quantitative clinical scales of the assessment of global mental status, depression and anxiety, as well as a wide battery of neuropsychological tests for the evaluation of executive/conceptual functions and memory, as well as attention verbal ability, and visuospatial skill functions. The performance of demented patients compared to normal controls was affected on all measurements except for depression and anxiety. DAT patients showed compared to MID patients a greater extent of impairment on tasks assessing verbal comprehension and memory while MID patients were more significantly impaired on measures of frontal lobe functioning. Clinically matched DAT and MID patients show a differential pattern of neuropsychological impairment when studied in an early stage of dementia and with a mild degree of severity. Such patterns might be of value for the development of clinical diagnostic criteria.