A Novel Study Paradigm for Long-term Prevention Trials in Alzheimer Disease: The Placebo Group Simulation Approach (PGSA): Application to MCI data from the NACC database

INTRODUCTION

The PGSA (Placebo Group Simulation Approach) aims at avoiding problems of sample representativeness and ethical issues typical of placebo-controlled secondary prevention trials with MCI patients. The PGSA uses mathematical modeling to forecast the distribution of quantified outcomes of MCI patient groups based on their own baseline data established at the outset of clinical trials. These forecasted distributions are then compared with the distribution of actual outcomes observed on candidate treatments, thus substituting for a concomitant placebo group. Here we investigate whether a PGSA algorithm that was developed from the MCI population of ADNI 1*, can reliably simulate the distribution of composite neuropsychological outcomes from a larger, independently selected MCI subject sample.

METHODS

Data available from the National Alzheimer's Coordinating Center (NACC) were used. We included 1523 patients with single or multiple domain amnestic mild cognitive impairment (aMCI) and at least two follow-ups after baseline. In order to strengthen the analysis and to verify whether there was a drift over time in the neuropsychological outcomes, the NACC subject sample was split into 3 subsamples of similar size. The previously described PGSA algorithm for the trajectory of a composite neuropsychological test battery (NTB) score was adapted to the test battery used in NACC. Nine demographic, clinical, biological and neuropsychological candidate predictors were included in a mixed model; this model and its error terms were used to simulate trajectories of the adapted NTB.

RESULTS

The distributions of empirically observed and simulated data after 1, 2 and 3 years were very similar, with some over-estimation of decline in all 3 subgroups. The by far most important predictor of the NTB trajectories is the baseline NTB score. Other significant predictors are the MMSE baseline score and the interactions of time with ApoE4 and FAQ (functional abilities). These are essentially the same predictors as determined for the original NTB score.

CONCLUSION

An algorithm comprising a small number of baseline variables, notably cognitive performance at baseline, forecasts the group trajectory of cognitive decline in subsequent years with high accuracy. The current analysis of 3 independent subgroups of aMCI patients from the NACC database supports the validity of the PGSA longitudinal algorithm for a NTB. Use of the PGSA in long-term secondary AD prevention trials deserves consideration.

[Consensus 2012--diagnosis and treatment of patients with dementia in Switzerland]

The 2012 Swiss consensus paper on diagnosis and management of patients suffering from dementia resulted from the work of an expert panel who met on March 23d to 25th in Luzem. Based on a literature review, panel members wrote a first draft that was subsequently circulated among multiple dementia experts in Switzerland. After adaptation and revisions according to comments, all consulted dementia specialists and panel members fully endorse the consensus content. The conference was financed by the Swiss Alzheimer Forum.

[Consensus recommendations for the assessment of fitness to drive in cognitively impaired patients]

Memory Clinics provide evidence based diagnosis and treatment of dementia. Whenever a diagnosis of dementia is made, it is important to inform the patients about the possible impact of dementia on driving. Patients and their next of kin require competent advice whenever this difficult question is addressed and the mobility desire and the risks related to driving need to be carefully weight up. The time of diagnosis does not necessarily equate to the time when a person with dementia becomes an unsafe driver. The cause and severity of dementia, comorbidities and the current medication need to be carefully taken into account for this decision. On behalf of the association of the Swiss Memory Clinics, a group of experts has developed recommendations to assess fitness to drive in cognitively impaired older adults.

Turning principles into practice in Alzheimer's disease

The prevalence of dementia is reaching epidemic proportions globally, but there remain a number of issues that prevent people with dementia, their families and caregivers, from taking control of their condition. In 2008, Alzheimer's Disease International (ADI) launched a Global Alzheimer's Disease Charter, which comprises six principles that underscore the urgency for a more ambitious approach to diagnosis, treatment and care. This review highlights some of the most important aspects and challenges of dementia diagnosis and treatment. These issues are reviewed in light of the six principles of the recent ADI Charter: promoting dementia awareness and understanding; respecting human rights; recognizing the key role of families and caregivers; providing access to health and social care; stressing the importance of optimal diagnosis and treatment; and preventing dementia through improvements in public health. The authors continue to hope that, one day, a cure for Alzheimer's disease will be found. Meanwhile, healthcare professionals need to unite in rising to the challenge of managing all cases of dementia, using the tools available to us now to work toward improved patient care.

Neuropsychological dysfunction, depression, physical disability, and coping processes in families with a parent affected by multiple sclerosis

Background

Families with a parent suffering from multiple sclerosis (MS) must cope with the unpredictable course of the disease. Most studies analyzing factors that influence coping abilities in families with a member affected with MS used questionnaires to assess this ability.

Methods

On the contrary, the present study used a semi-structured psychiatric interview and used the resulting information to calculate a general measure of coping ability (coping index [CI]). We administered this interview to 44 MS patients, their partners and offspring and conducted a neuropsychological and physical evaluation of the patients to determine the impact of physical disability, cognitive dysfunction, and depression on the process of coping by the patient, the healthy partner, and children.

Results

The CI of patients was best predicted by measures of their depressive symptoms, divided attention, and estimated verbal intelligence. None of the patient variables predicted the CI of healthy partners or their offspring. We found an association between the CI of the healthy partner and the children.

Conclusions

These findings suggest that MS patients’ emotional and neuropsychological functions are associated with their ability to cope with the disease. These should be carefully assessed at the beginning of treatment so that those factors known to negatively influence patient coping are targeted in the treatment plan if necessary. Comprehensive care of a patient with MS should include support of coping abilities of the family members.

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.

Weight change and cognitive performance

OBJECTIVE

To investigate whether under- or overweight and weight change is associated with cognitive performance of elderly citizens.

DESIGN

Explorative analysis out of the Basel Study cohort.

SUBJECTS

In all, 531 healthy subjects (445 men/86 women) were assessed with the Consortium to Establish a Registry for Alzheimer's Disease-Neuropsychological Assessment Battery (CERAD-NAB) in 2000 (age: 69.4+/-7.8 y) and weight measurements obtained in 1990 (body mass index (BMI): 25.2+/-3.1 kg/m(2)) and in 2000 (BMI: 25.6+/-3.4 kg/m(2)).

METHODS

The predictive power of the annual change in BMI with cognitive performance was investigated by a binary logistic regression analysis (backward) using sex, age, BMI 1990, BMI 2000, diastolic blood pressure, diabetes status, and optimal health status as additional predictors.

RESULTS

In the last step, the following variables remained in the model: annual change in BMI (quadratic term; P<0.01); ApoE genotype (P<0.05); and optimal health status (P<0.01).

CONCLUSION

The association between the extent of weight change and poorer cognitive performance could be either a consequence of cognitive impairment or an early symptom of neurodegenerative decline.

Normal ranges of neuropsychological tests for the diagnosis of Alzheimer's disease

The diagnosis of early stage dementia is a highly complex process involving not only a somatic examination but also a neuropsychological assessment of the patient's cognitive capability. The American 'Consortium to Establish a Registry for Alzheimer's Disease' (CERAD) has proposed a set of tests in English which has been translated into German. This paper presents the statistical methodology applied to determine normal ranges adjusted for demographic variables for the German CERAD neuropsychological assessment battery (CERAD-NAB). The study population consists of participants of the Basel Study on the Elderly (Project BASEL) which aims at identifying preclinical markers of Alzheimer's disease. The normative sample has been defined by carefully excluding potentially relevant medical history and concomitant diseases and consists of 617 participants which are between 53 and 92 years old. Test results should be adjusted for gender, age, and years of education. For this purpose, a set of linear models including these predictors and subsets of their interactions and squares was evaluated for all 11 test scores derived from the CERAD-NAB battery. Model selection was based on the PRESS (predicted residual sum of squares) statistic. Although a strict application of this criterion selected 6 different models, a slight compromise allowed to fit all test scores by two models. In several tests of the CERAD-NAB many participants achieve maximal scores. Residuals of such test scores are heavily skewed. An arcsine transformation has been tuned to the data, so that residuals are close to a normal distribution, at least for residuals in the lower quartile which is relevant in diagnosing cognitive impairment. Test results are finally presented as z-scores which can be easily compared to a standard normal distribution. The evaluation of the CERAD-NAB is implemented on the Internet and in an Excel application.

Assessment of dementia in elderly outpatients: a comparative study of European centers and consensus statement

Large numbers of elderly patients, suspected of having dementia, need medical evaluation, often in early phases of their illness. A complete outpatient assessment clearly could be advantageous. Thirty-five centers from 15 European countries, known to their scientific gerontological and geriatric societies to have experience in outpatient care for elderly patients with dementia, participated in an effort to develop a consensus statement for the assessment needs of these patients. The comparison of the centers showed that a wide variety of approaches was currently in practice. Differences appeared to be mainly based on local facilities and organization. A consensus for diagnostic outpatient assessment was easily reached. Diagnosis should be based on DSM-IV criteria, which requires a standardized assessment (including neuropsychological, functional and technical evaluation) and should be multidisciplinary. An assessment of dementia of elderly outpatients appears to be very feasible - a consensus approach with minimum diagnostic requirements is presented.

Pflegende Familienangehörige von Demenzpatienten

Zusammenfassung: Zweiundsiebzig Angehörige (AG) von Demenzpatienten wurden über ihre Belastung und ihre Bedürfnisse befragt. Angst, Depression sowie subjektive Belastung traten häufiger in späteren Demenzstadien auf und waren ausgeprägter, je beeinträchtigter das Alltagsverhalten (Nurses' Observation Scale for Geriatric Patients «NOGER», Spiegel et al., 1991 ) des Patienten und je schlechter die eigene subjektive Gesundheit beurteilt wurde. Im multivariaten Regressionsmodell konnten 66 % der subjektiven Belastung durch die Angst der AG, die Hilfe durch die Familie/Freunde sowie durch die NOSGER-Dimensionen «Selbstpflege» und «störendes Verhalten» erklärt werden (F 4,71) = 32.2, p < .0001). Die Bedürfnisse betrafen v. a. den Wunsch nach Information über und den Umgang mit der Krankheit sowie Betreuungsmöglichkeiten. Entlastende Unterstützungsangebote würden den AG ermöglichen, ihre Patienten länger zuhause zu betreuen.

[Argyrophilic grain disease: differentiation from Alzheimer disease]

Argyrophilic grain disease (AgD) constitutes one cause of late onset dementia and is histologically characterized by the presence of abundant argyrophilic grains and coiled bodies. Both abnormalities are found mainly in limbic structures, among them the sector CA1 of the hippocampus, the entorhinal cortex, and the amygdala. Using appropriate silver staining techniques, they are easily detectable and can easily be distinguished from neurofibrillary lesions of Alzheimer's disease (i.e., tangles and threads). Although the histopathology of AgD is well characterized, the nosological status is still unclear because most cases of AgD are associated with Alzheimer-type changes. For some authors, therefore, AgD is considered a variant of Alzheimer's disease rather than a distinct disease entity. The present review is aimed at presenting argyrophilic grain disease to a larger readership than just neuropathologists who are interested in neurodegenerative disorders. In this review we summarize morphological, immunohistochemical, clinico-pathological and genetic data obtained in more than 90 subjects with AgD. The main conclusions of this review are that AgD represents one of the most frequent, dementing disorders of old age and that it has to be clearly distinguished from Alzheimer's disease.

Apolipoprotein E allele frequencies in argyrophilic grain disease

Apolipoprotein E (ApoE) genotypes were analyzed in 35 subjects with argyrophilic grain diseases (AgD). Neuropathologically, all cases were characterized by abundant argyrophilic grains in the hippocampus and in the entorhinal or parahippocampal cortex. We found an ApoE epsilon4 allele frequency of 0.007 in AgD patients, which is significantly different from the epsilon4 allele frequencies reported in age-matched Alzheimer's disease (AD) patients (0.24), but not from age-matched controls (0.09). We conclude that the ApoE epsilon4 allele does not constitute a risk factor for the development of AgD. Our results further suggest that AgD is a progressive disorder differentiated from AD by morphological and genetic criteria.

Memory Clinics in Switzerland. Collaborative Group of Swiss Memory Clinics

Currently, eleven Memory Clinics (MC) in Switzerland offer their services to patients, caregivers and family doctors. Their primary goal is the early diagnosis and management of dementia in elderly outpatients. Special emphasis is put on the detection of reversible causes of dementing disorders. Diagnoses and medical, pharmacological, neuropsychological and social treatment recommendations are established in a multidisciplinary consensus conference and communicated back to the referring physicians. The psychosocial therapies and supportive activities include counseling, memory training for patients, neuropsychological rehabilitation, caregiver groups, relaxation and biofeedback training, day care centers, Alzheimer's Tanzcafé, and special vacations for dementia patients. These activities vary from MC to MC according to the availability of resources. Research activities are an integral part of all MCs and range from the attempt to identify preclinical markers of Alzheimer's disease to studies of neuropathological correlates of cognitive disturbances. Moreover, patients are encouraged to participate in studies investigating new medications. MCs play an important role in the education and training of health care professionals and in raising awareness and support in the general population.

Early diagnosis of dementia via a two-step screening and diagnostic procedure

We propose a two-step process for the assessment of dementia using standardized instruments. The family physician performs a screening consisting of taking a medical history, gathering information from relatives and friends of the patient, and administering the combined Mini-Mental State Examination (MMSE) and Clock Drawing Test (CDT). Specialists examine patients with suspected dementia to confirm the diagnosis of dementia and, after a thorough differential diagnostic process, provide the family physician with recommendations for treatment. Specialists should perform neurological and psychiatric examinations, imaging (computer-assisted tomography [CT], magnetic resonance imaging [MRI]), and laboratory work-up. The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) core neuropsychological battery is proposed to serve as a minimal data set that is internationally compatible. In addition, we recommend the Nurses' Observation Scale for Geriatric Patients (NOSGER) as a standard tool for functional assessment.

Argyrophilic grain disease: distribution of grains in patients with and without dementia

In a previous study we reported on a late onset dementia which occurred in only half of the patients with argyrophilic grain disease (AgD) investigated. To find a correlation between the distribution of argyrophilic grains (ArG) and the occurrence of a late onset dementia, we examined the limbic area in 35 subjects who had ArG as the main neuropathological finding. A retrospective clinical analysis was performed by collecting information from hospital charts supplemented by standardized interviews based on DSM IV criteria for dementia. Sections from the rostral and caudal hippocampal regions, including the entorhinal/transentorhinal and parahippocampal cortex on both sides, were strained by the Gallays method. Nineteen subjects were diagnosed as demented according to these criteria; 16 were considered to have been cognitively normal. High numbers of ArG were observed in the anterior part of the CA1 subfield in all cases. However, the posterior half of CA1 was involved significantly more often and more severely in demented than in non-demented individuals (P < 0.01). Moreover, the distribution of ArG in the entorhinal/transentorhinal and parahippocampal cortex was more widespread in the group of demented patients (P < 0.05). These results show that the intellectual status of patients with AgD was related to the extension of ArG in the limbic area. We suggest that AgD is a progressive neurodegenerative disorder with early subclincial lesions in the anterior part of the hippocampal formation. To provide a more accurate clinicopathological correlation, the rostrocaudal extension of ArG in the limbic area should be evaluated in AgD cases.

[Neuropsychological examination in evaluating dementia]

Neuropsychological assessment of dementia should be obtained using a two-step procedure: 1) a family physician performs a mental screening; 2) specialists determine the diagnosis after a thorough differential diagnostic process. This second step includes the quantitative neuropsychological assessment of the patients' cognitive functions which has the following purposes: a) to contribute to the differential diagnostic process; b) to aid in diagnosing patients at the earliest stage of dementia; c) to document disease progression and therapy outcomes; and, d) to identify relatively intact areas of cognition to serve as a basis for cognitive therapy. A Swiss consensus to utilize the Consortium to Establish a Registry for Alzheimer's disease (CERAD) Neuropsychological Battery as a minimal standard assessment instrument is introduced.

Category fluency is also predominantly affected in Swiss Alzheimer's disease patients

OBJECTIVES

To establish the comparative efficacy to differentiate between Swiss patients with dementia of the Alzheimer type (DAT) and elderly normal control subjects (NC) on two different verbal fluency tasks: category fluency and letter fluency.

MATERIAL AND METHODS

Fifty Swiss German DAT patients in the early stages of the disease and 50 matched normal control subjects were compared on letter and category fluency tasks.

RESULTS

DAT patients exhibited an overproportional impairment on category fluency as compared with letter fluency. Receiver operating characteristic curves (ROC) showed that category fluency correctly classified a significantly higher number of DAT patients and NC subjects (84%) than letter fluency (70%).

CONCLUSION

As similar findings have been described for English-speaking DAT patients, we conclude that deficiencies in category fluency are a general phenomenon, reflecting impaired structures of semantic knowledge occurring early in the course of Alzheimer's disease.

Random number generation in dementia of the Alzheimer type: a test of frontal executive functions

The quality of attempts at generating a random sequence of the numbers 1-6 was studied in 30 patients with dementia of the Alzheimer type (DAT) and 30 elderly normal control (NC) subjects. Three main findings emerged: (1) DAT patients' subjective random sequences were more streotyped (contained fewer digit combinations) than those of NC subjects. (2) This difference in response stereotypy was due to patients' enhanced tendency to arrange consecutive numbers in an ascending series ('counting bias'). (3) In the patient group, degree of sequential nonrandomness was positively correlated with overall severity of dementia and with the extent to which performance on neuropsychological tests specifically assessing executive functions (fluency, naming, error monitoring) was impaired. These results illustrate a loss of behavioral complexity in the course of dementia and are interpreted as reflecting a frontal dysexecutive syndrome in DAT.

Screening for dementia of the alzheimer type in the community: the utility of the Clock Drawing Test

This study reports the sensitivity and specificity of the Clock Drawing Test (CDT) for detecting dementia of the Alzheimer type in a community-dwelling sample of elderly subjects. Forty-two patients with clinically diagnosed Alzheimer's disease and 237 cognitively intact subjects were administered the CDT as part of an epidemiological study of aging and dementia. Three individual measures of clock drawing performance (quantitative score, qualitative score, and combined quantitative and qualitative score) were determined for each participant. When qualitative elements such as errors and strategies were incorporated into the CDT score, the sensitivity was 84% and the specificity was 72%. The findings suggest that a CDT score which evaluates qualitative and quantitative features provides reasonably good discrimination between normal elderly individuals and DAT patients. However, the CDT appears to have limited utility as a single screening instrument in the community. Instruments such as the Dementia Rating Scale (Mattis, 1976) provide better discrimination of DAT, indicating that functions such as memory and verbal fluency need to be assessed during screening.

Repetitive behavior and repetition avoidance: the role of the right hemisphere

Based on clinical observations of patients suffering from brain damage, a recent model assumes a right hemisphere dominance for the suppression of repetitive behavior. This study set out to test whether or not the well-known effect of repetition avoidance in sequential response production is likewise mediated by the right hemisphere. It was found that, in 40 healthy subjects, avoidance of repetitions in a random number-generation task correlated positively with a relative superiority for design as compared to letter fluency. Since design fluency is predominantly mediated by the right frontal lobe and letter fluency by the left, this finding supports the notion of a right hemisphere dominance for the avoidance of repetitive responses. This study illustrates the usefulness of a neurobehavioral approach to repetition behavior in the randomization of response. In particular, it demonstrates that the phenomenon of repetition avoidance may be better accounted for in terms of a control mechanism preventing perservation than by referring to human subjects' "generally biased concept of randomness."

Episodic memory changes are associated with the APOE-epsilon 4 allele in nondemented older adults

OBJECTIVE

To compare the memory performances of nondemented older adults with and without the epsilon 4 allele of the apolipoprotein E (APOE-epsilon 4).

BACKGROUND

Few studies have examined the cognitive status of subjects at high risk for the development of dementia of the Alzheimer type (DAT). A newly reported risk factor for DAT allows for an examination of the cognitive performances of nondemented subjects who are at risk by virtue of being either heterozygous or homozygous for the APOE-epsilon 4 allele.

METHODS

The California Verbal Learning Test (CVLT) was administered to 52 nondemented older adults. Subjects were divided into two groups on the basis of the presence (n = 17) or absence (n = 35) of one or two APOE-epsilon 4 alleles.

RESULTS

APOE- epsilon 4 and non-epsilon 4 groups did not significantly differ in demographic, mental status, and functional characteristics. APOE-epsilon 4 subjects demonstrated significantly poorer mean performances than non-epsilon 4 subjects on nine CVLT variables. Seven group differences remained significant, and three approached significance (0.05 < p < 0.10), after the effects of age and gender were taken into account. Six of the 14 APOE-epsilon 4 subjects who completed annual follow-up evaluations developed either DAT or questionable DAT, whereas none of the 26 non-epsilon 4 subjects who received follow-up demonstrated any cognitive decline.

CONCLUSIONS

Results suggest that episodic memory changes in older adults are associated with APOE-epsilon 4 allele; sensitive cognitive markers such as those of the CVLT may precede the subsequent development of DAT.

Clinical validity of the Mattis Dementia Rating Scale in detecting Dementia of the Alzheimer type. A double cross-validation and application to a community-dwelling sample

OBJECTIVE

To assess the clinical validity of the Dementia Rating Scale (DRS) in detecting patients with dementia of the Alzheimer type (DAT).

BACKGROUND

The DRS is widely used to evaluate cognitive functioning in older adults. Adequate normative data are unavailable; studies addressing the clinical validity of the DRS are limited by small sample sizes.

DESIGN AND METHODS

Administered the DRS to 254 outpatients with DAT and 105 healthy elderly subjects. Performed (1) multiple regressions of demographic factors on the DRS and its subscales; (2) derivation of optimal DRS cutoff scores using receiver operating characteristic curves; (3) double cross-validation with stepwise logistic regressions; and (4) application of results to a community-dwelling sample.

RESULTS

Age- and education-adjusted DRS scores were computed. The optimal DRS cutoff score for DAT of 129 or less revealed a sensitivity of 98% and a specificity of 97%. The logistic regressions resulted in a combination of the Memory and Initiation/Perseveration subscales that correctly classified 98% of all subjects, 92% of a subsample of 76 patients with mild DAT, and 100% of the 51 patients with autopsy-confirmed DAT. The resultant equation was then applied to a community-dwelling sample (238 healthy elderly subjects and 44 patients with DAT): 91% of patients and 93% of normal subjects were correctly classified. Of an additional 77 individuals with questionable DAT, 43 were classified as demented and 34 were classified as nondemented.

CONCLUSIONS

The DRS is a clinically valid psychometric test for the detection of DAT. The Memory and Initiation/Perseveration subscales are its best discriminative indexes for an abbreviated version.

Improving the diagnostic accuracy of the Mini-Mental State Examination

INTRODUCTION

We determined the diagnostic accuracy of the Mini-Mental State Examination (MMSE) for dementia of the Alzheimer type (DAT) in an outpatient geriatric referral center in Switzerland.

MATERIAL & METHODS

DAT patients and elderly controls were assigned to two groups: a validation sample (70 DAT patients; 50 controls) and a cross-validation sample (133 DAT patients; 43 controls). A Receiver Operating Characteristic curve was generated to derive the optimal MMSE cut-off score in the validation sample.

RESULTS

The optimal MMSE cut-off was < 26/30 (sensitivity of 74%, specificity of 100%). Adjustments for age and education were necessary. The cross-validation confirmed these findings.

CONCLUSION

iN A clinical setting the MMSE cut-off should be increased to < 26/30. A thorough neurobehavioral assessment is still necessary for a complete evaluation.

Unawareness of smell loss in normal aging and Alzheimer's disease: discrepancy between self-reported and diagnosed smell sensitivity

Awareness of loss in smell sensitivity was assessed in 80 normal elderly subjects, 80 patients with probable Alzheimer's disease (AD), and 80 patients with sinusitis by comparing measured smell sensitivity to questionnaire-based, self-reported sensitivity. Both AD patients and sinusitis patients had significantly poorer diagnosed smell sensitivity than the normal elderly. Both patient groups had thresholds which on average were about nine times more concentrated than those of the normal elderly. However, 74% of the AD patients and 77% of the normal elderly with smell loss reported normal smell sensitivity. In contrast, only 8% of the sinusitis patients with loss reported normal smell sensitivity.

Folstein vs modified Mini-Mental State Examination in geriatric stroke. Stability, validity, and screening utility

OBJECTIVE

Two studies were conducted with the Folstein Mini-Mental State Examination (MMS) and the Modified Mini-Mental State Examination (3MS) to examine whether the expanded version is a more useful screening tool in stroke populations.

DESIGN

Clinical utility of screening tests (MMS and 3MS) was evaluated in reference to neuropsychological performance and functional outcome in rehabilitation.

SETTING

Medical rehabilitation unit of university-affiliated hospital.

PATIENTS

Two groups (n = 77, and n = 70) of patients who were admitted consecutively.

MAIN OUTCOME MEASURES

Neuropsychological performance and functional outcome (functional independence measure).

RESULTS

The reliability, stability, and validity of the 3MS were established in the stroke population. Classification accuracy did not differ between the MMS and 3MS, although the 3MS had higher sensitivity. In detecting cognitive impairment when compared with the extended neuropsychological battery, both instruments were adequate in patients with left-sided cerebrovascular accidents and were ineffective in patients with right-sided cerebrovascular accidents. The 3MS correlated with some cognitive domains missed by the MMS, thus adding useful clinical information. Finally, the 3MS was a significantly better predictor of functional outcome than the MMS.

CONCLUSIONS

The 3MS was found to be a reliable, valid, and stable cognitive screening instrument in the stroke population. Classification accuracy indicates that both screening instruments are not strong in their ability to detect cognitive impairment in patients with stroke, especially in right-sided cerebrovascular accidents. The 3MS does have some advantages over the MMS; the expanded version of the screen not only provides additional cognitive information but also allows for better predicting of functional outcome.

Neuropsychological studies of asymptomatic human immunodeficiency virus-type-1 infected individuals. The HNRC Group. HIV Neurobehavioral Research Center

The current review was conducted to address the ongoing debate regarding the presence or absence of neuropsychological impairment in asymptomatic HIV-Type 1 (HIV-1) seropositive individuals. Results were summarized from 57 studies that compared the performances of seropositive asymptomatic and seronegative individuals. Overall, the differences observed between median rates of impairment for asymptomatic (35%) and seronegative (12%) groups provided the clearest indication of deficits in asymptomatics. In addition, five variables were examined as possible contributors to inconsistencies found in the literature: mode of infection, test battery type, test battery size, sample size, and method of data analysis. Of these variables, only mode of infection and test battery size appeared to substantially influence the outcome of the studies reviewed with regard to identifying neuropsychological impairment in asymptomatics.

Discrimination of cortical from subcortical dementias on the basis of memory and problem-solving tests

This study compared the discriminative utility of problem-solving and memory tasks in patients with Alzheimer's and Huntington's disease and in age-, education-, and gender-matched normal control subjects. Problem-solving was assessed with a modified version of the Wisconsin Card Sorting Test. Memory was measured with a 10-item, 6-trial version of the Buschke Selective Reminding Test. Receiver Operating Characteristic curves were plotted to determine which measure provided the highest sensitivity (i.e., hit rate) and specificity (i.e., correct rejection rate). Both tests provided excellent detection of dementia (88 to 98% classification accuracy), but were less robust in differentiating between dementia groups. Findings underscore the suitability of both measures to detect mild dementia, but emphasize the importance of specific memory measures to differentiate between cortical and subcortical dementia.

Comparisons of verbal fluency tasks in the detection of dementia of the Alzheimer type

The performances of 89 patients with dementia of the Alzheimer type (DAT) and 53 demographically matched elderly normal control subjects were compared on four verbal fluency measures (category, letter, first names, and supermarket fluency). Receiver operating characteristic curves were plotted to determine each fluency tasks' sensitivity (ie, true-positive rate) and specificity (ie, true-negative rate). Category fluency demonstrated the greatest degree of discrimination between patients with DAT and normal control subjects (sensitivity, 100%; specificity, 92.5%); letter fluency was the least accurate (sensitivity, 89%; specificity, 85%). Separation of patients with DAT by gender revealed similar findings. In further analyses with a subgroup of 21 mildly impaired patients with DAT, category fluency lost none of its discriminative capabilities, whereas all other fluency measures showed marked reductions in discriminability. We conclude that this superiority of category fluency is due to its dependence on the structure of semantic knowledge, which deteriorates in the early stages of DAT.

Safety and effectiveness of low-dose clozapine in psychogeriatric patients: a preliminary study

The short- and long-term treatment tolerance of low-dose clozapine was retrospectively investigated in 18 psychogeriatric patients. Discontinued use of the drug because of side effects or inefficiency was required for only four patients. In the long-term treatment group leukopenia was not observed, and disturbances of liver function appeared to be very infrequent. A second group of seven severely demented psychogeriatric inpatients who were currently being treated with low-dose clozapine underwent a withdrawal study in order to evaluate the therapeutic efficacy of the drug, measured by the NOSIE and the SCAG scales. The results indicate that for patients such as these, with paranoid or socially disturbing behavior who also tend to develop severe neurological side effects with classical neuroleptics, a low-dose administration of clozapine is an acceptable alternative treatment.