Cognitive decline in Alzheimer's disease: elaborating on the nature of the longitudinal factor structure of the Mini-Mental State Examination

Effects of 6-month at-home transcranial direct current stimulation on cognition and cerebral glucose metabolism in Alzheimer's disease

BACKGROUND

Although single or multiple sessions of transcranial direct current stimulation (tDCS) on the prefrontal cortex over a few weeks improved cognition in patients with Alzheimer's disease (AD), effects of repeated tDCS over longer period and underlying neural correlates remain to be elucidated.

OBJECTIVE

This study investigated changes in cognitive performances and regional cerebral metabolic rate for glucose (rCMRglc) after administration of prefrontal tDCS over 6 months in early AD patients.

METHODS

Patients with early AD were randomized to receive either active (n = 11) or sham tDCS (n = 7) over the dorsolateral prefrontal cortex (DLPFC) at home every day for 6 months (anode F3/cathode F4, 2 mA for 30 min). All patients underwent neuropsychological tests and brain ¹⁸F-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) scans at baseline and 6-month follow-up. Changes in cognitive performances and rCMRglc were compared between the two groups.

RESULTS

Compared to sham tDCS, active tDCS improved global cognition measured with Mini-Mental State Examination (p for interaction = 0.02) and language function assessed by Boston Naming Test (p for interaction = 0.04), but not delayed recall performance. In addition, active tDCS prevented decreases in executive function at a marginal level (p for interaction < 0.10). rCMRglc in the left middle/inferior temporal gyrus was preserved in the active group, but decreased in the sham group (p for interaction < 0.001).

CONCLUSIONS

Daily tDCS over the DLPFC for 6 months may improve or stabilize cognition and rCMRglc in AD patients, suggesting the therapeutic potential of repeated at-home tDCS.

The effectiveness of diverse technology-based instructions in assisting people with Alzheimer's disease with medication management

Purpose: In patients with mild cognitive impairment and Alzheimer's disease (AD), faculties associated with instrumental activities of daily living (IADL) decline owing to reduced cognitive function. One type of IADL is medication behaviour. Medication management is critical for patients with AD. Previous studies have reported that presentations using speech and images are effective for facilitating IADL autonomy but there are few examinations of effective presentation methods. Therefore, we examined what kind of display methods are effective in helping patients with AD with medication management.Materials and methods: Ten healthy elderly and 9 patients with mild AD were asked to perform the task of taking out medicine bags from a case at a designated time. We gave 3 kinds of instructions and examined the differences in participants' reaction times. Task 1 included verbal instructions alone, Task 2 included verbal instructions and pictorial and written instructions, and Task 3 used a video conference system (presenting pictorial, written, and verbal instructions) at a designated time. Task 3 could be conducted remotely over the internet. The relationship between these results and neuropsychological tests was also explored.Results: Task 3 was an effective method for patients with mild AD. In addition, we found correlations between the methods of Tasks 1-3 and the Japanese version of the Mini-Mental State Examination (MMSE-J).Conclusions: The method of Task 3 may lead to home support for patients with AD. The MMSE-J could be used to identify changes in the adaptive functioning of patients exposed to distinct presentation methods.Implications for rehabilitationAppropriate transmission methods will increase the IADL autonomy of patients with mild AD who have memory impairment. While still images alone are not effective for patients with mild AD, when combined with verbal instructions, they prove effective for this group.The results of this study are useful for providing patients with mild AD with support in their IADLs, especially when methods that use images plus speech are employed. As participants were instructed via the internet, this study shows a way to help patients with mild AD even from a remote location.Until now, no studies have examined the adaptation criteria for instructive methods for patients with mild AD. This study shows that the MMSE could be used to determine the applicability of these instructive methods. The identification of cut-off values in future research could lead to more effective IADL support.

Principal components analysis of agitation outcomes in Alzheimer's disease

BACKGROUND

We developed a composite measure of agitation as a secondary outcome of change over time in the Citalopram for Agitation in Alzheimer's disease study (CitAD). CitAD demonstrated a positive effect of citalopram on agitation on the Neurobehavioral Rating Scale agitation subscale (NBRS-A). CitAD included additional agitation measures such as the Cohen-Mansfield Agitation Inventory and the Neuropsychiatric Inventory.

METHODS

We performed principal components analyses on change in individual item of these scales for the same, original CitAD subjects.

RESULTS

The first principal component accounted for 12.6% of the observed variance and was composed of items that appear to reflect agitation. The effect size for citalopram calculated using this component was 0.53 (95% CI 0.22-0.83) versus 0.32 for the NBRS-A (95% CI 0.01-0.62).

CONCLUSIONS

Results suggest that a composite measure of change in agitation might be more sensitive than change in a single primary agitation measure.

[Standardization of the Test Your Memory and evaluation of their concordance with the outcome of the psychometric examination]

OBJECTIVE

To explore the relationship between scores on the Test Your Memory (TYM) battery and findings from a more exhaustive neurocognitive assessment.

METHODS

The TYM and fourteen psychometric tests were administered to 84 subjects aged 50 or older who attended an outpatient neurology clinic due to cognitive symptoms. Each patient's cognitive state was determined independently from his/her score on the TYM (CDR 0, n=25; CDR 0.5, n=45; CDR 1, n=14). We analysed concurrent validity of TYM scores and results from the psychometric tests, as well as the degree of concordance between the two types of measurement, by contrasting normalised data from each instrument.

RESULTS

Although the intraclass correlation coefficient was 0.67 (confidence interval 95%, 0.53-0.77), analysis of the Bland-Altman plot and the curve on the survival-agreement plot (Luiz et al. method) demonstrates that the individual distances between the two methods exhibit excessive dispersion from a clinical viewpoint. TYM-based predictions of the mean z-score on psychometric tests differed substantially from real results in 30% of the subjects. Concordance of 95% can only be achieved by accepting absolute inter-instrument differences of up to 0.87 as identical values. Furthermore, the TYM underestimates cognitive performance for low values and overestimates it for high values.

CONCLUSIONS

The TYM is a cognitive screening test which should not be used to predict results on psychometric tests or to detect cognitive changes in clinical trials.

Predicting cognitive decline in Alzheimer's disease: an integrated analysis

BACKGROUND

Numerous patient- and disease-related factors increase the risk of rapid cognitive decline in patients with Alzheimer's disease (AD). The ability of pharmacological treatment to attenuate this risk remains undefined.

METHODS

Pooled data from 14 randomized clinical studies of donepezil in the treatment of AD (N = 3748) were analyzed to identify predictors of fast decline and determine the effect of donepezil on the risk of fast decline.

RESULTS

Young age and more severe baseline cognitive, global, or behavioral status were identified as independent predictors of faster decline in placebo-treated patients. Multivariate models indicated that donepezil treatment was associated with a 39% to 63% reduction in the risk of faster decline.

CONCLUSIONS

These results correspond with previous findings, indicating relationships between age or baseline disease severity and rates of cognitive decline. Furthermore, they suggest that symptomatic therapy for AD could reduce the likelihood of faster decline in treated patients.

Donepezil: A Review of Pharmacological Characteristics and Role in the Management of Alzheimer Disease

Donepezil is a potent, selective, noncompetitive, and rapidly reversible inhibitor of acetylcholinesterase (AChEI) licensed for the treatment of Alzheimer disease (AD); and is the first and only AChEI licensed for the treatment of severe AD. Its efficacy as monotherapy, or in combination with the NMDA-agonist, memantine, has been documented in several randomised double-blind, placebo-controlled, short-term clinical trials, as well as long-term extension trials and observational studies. Donepezil is a well tolerated drug that is generally safe as demonstrated even in patients with multiple co-morbidities receiving polypharmacy. It has been shown that donepezil improves cognition and global function in patients with mild-to-moderate AD; and long-term efficacy is maintained for up to 50 weeks. There is a dose-response relationship, with higher doses more likely to produce symptomatic benefit. Furthermore, donepezil-treated patients may improve cognitively and show global clinical improvement in all disease stages, including severe AD. Less consistent results in all disease stages were obtained on measures of function and behavior, and observations of mood. No effect on transition to AD has been found in long-term, randomized clinical trials in mild cognitive impairment (MCI). Cost-effectiveness of the treatment has been questioned by one long-term open-label societal study of 2-years duration. This study reported modest improvement of cognition but no statistically significant benefits during donepezil treatment as compared to placebo, in terms of rates of institutionalization and progression toward greater disability. However, there is a need for further research on clinically meaningful outcomes and treatment benefits favored by patients and caregivers, which are traditionally not defined as outcomes in clinical trials. Likewise, we need to know how to select responders, what is an optimal AChE inhibition particularly during the long-term treatment, in which patients the dosage should be increased for a sustained benefit, what is the optimal duration of treatment and when is meaningful to stop the treatment. After almost two decades of donepezil use in everyday clinical practice these issues are still unresolved.

The MMSE orientation for time domain is a strong predictor of subsequent cognitive decline in the elderly

BACKGROUND

The mini-mental state exam (MMSE) has been used to address questions such as determination of appropriate cutoff scores for differentiation of individuals with intact cognitive function from patients with dementia and rate of cognitive decline. However, little is known about the relationship of performance in specific cognitive domains to subsequent overall decline.

OBJECTIVE

To examine the specific and/or combined contribution of four MMSE domains (orientation for time, orientation for place, delayed recall, and attention) to prediction of overall cognitive decline on the MMSE.

METHODS

Linear mixed models were applied to 505 elderly nursing home residents (mean age = 85, > 12 years education = 27%; 79% F, mean follow-up = 3.20 years) to examine the relationship between baseline scores of these domains and total MMSE scores over time.

RESULTS

Orientation for time was the only domain significantly associated with MMSE decline over time. Combination of poor delayed recall with either attention or orientation for place was associated with significantly increased decline on the MMSE.

CONCLUSIONS

The MMSE orientation for time predicts overall decline on MMSE scores over time. A good functioning domain added to good functioning delayed recall was associated with slower rate of decline.

Donepezil in More Advanced Alzheimer's Disease

OBJECTIVE

Donepezil is currently approved for treatment of patients with mild to moderate Alzheimer's disease (AD). However, since cholinergic activity declines as AD progresses, increasing acetylcholine levels would be expected to provide benefits in severe AD. The primary objective of this article is to review the recent data demonstrating that patients with advanced AD can benefit from treatment with the cholinesterase inhibitor donepezil.

DATA SOURCES

A MEDLINE (PubMed) literature search was performed using the key words "donepezil" and "advanced AD."

STUDY SELECTION

The search yielded 13 articles, which were then further screened for the criterion: randomized, double-blind, placebo-controlled clinical study.

DATA EXTRACTION AND SYNTHESIS

Two studies were found that met these specific study criteria. In the first study, donepezil-treated patients with moderate to severe AD showed significant improvements in cognition and behavior, with preservation of activities of daily living compared with placebo-treated patients. Similar improvements in donepezil-treated patients were seen in the second study involving 27 nursing homes. In this study of older patients, donepezil treatment significantly improved cognition, function, and agitated and aggressive behaviors. Safety and tolerability findings of these two studies are further assessed. Considerations for drug therapy as well as a case study are presented to illustrate the benefits of donepezil treatment in patients with advanced AD.

CONCLUSION

. The decision to continue treating severe AD patients with donepezil is an opportunity for consultant pharmacists to decrease the burden of caregivers and to maximize a patient's quality of life for as long as possible.

Target symptoms and outcome measures: cognition

The Cognitive section of the Alzheimer's Disease Assessment Scale (ADAS-Cog) remains the most widely used cognitive measure in dementia trials although it does not assess attention, executive function, or agnosia. Designed for use in Alzheimer's disease (AD), it may not be ideal in assessing patients with other diagnoses. The ADAS-Cog differentiates between AD patients, patients with Mild Cognitive Impairment, and normal controls. It has been used in trials of drugs for vascular and mixed dementia and dementia with Lewy bodies. It is not clear that the ADAS-Cog is adequate for assessing cognition in frontotemporal dementia. Well-validated aphasia batteries, such as the Western Aphasia Battery, can be used to assess language. Brief tests of frontal function such as the Frontal Assessment Battery or the Executive Interview might be useful additions in frontotemporal dementia trials. The most widely used assessment tool for patients with advanced dementia is the Severe Impairment Battery. The domains tested are analogous to those assessed by the ADAS-Cog. The Mini-Mental State Exam and the Modified Mini-Mental State Examination are useful in stratifying patients for trial entry. Cognitive measures better tailored to the diseases in question are needed for non-Alzheimer dementias.

3-year study of donepezil therapy in Alzheimer's disease: effects of early and continuous therapy

Delays in the diagnosis of Alzheimer's disease, and, therefore, delays in treatment, may have a detrimental effect on a patient's long-term well-being. This study assessed the effects of postponing donepezil treatment for 1 year by comparing patients treated continuously for 3 years with those who received placebo for 1 year followed by open-label donepezil for 2 years. Patients (n = 286) with possible or probable Alzheimer's disease (according to DSM-IV, NINCDS-ADRDA, and Mini-Mental State Examination criteria; see text) were randomized to receive donepezil (5 mg/day for 4 weeks, 10 mg/day thereafter) or placebo (delayed-start group) for 1 year. Of the 192 completers, 157 began a 2-year, open-label phase of donepezil treatment. Outcome measures were the Gottfries-Bråne-Steen scale, the Mini-Mental State Examination, the Global Deterioration Scale, the Progressive Deterioration Scale, the Neuropsychiatric Inventory, and safety (adverse events). Mixed regression analysis was used to compare changes between the groups over 3 years on the efficacy measures. There was a trend for patients receiving continuous therapy to have less global deterioration (Gottfries-Bråne-Steen scale) than those who had delayed treatment (p = 0.056). Small but statistically significant differences between the groups were observed for the secondary measures of cognitive function (Mini-Mental State Examination; p = 0.004) and cognitive and functional abilities (Global Deterioration Scale; p = 0.0231) in favor of continuous donepezil therapy. Over 90% of the patients in both cohorts experienced one treatment-emergent adverse event; most were considered mild or moderate. In conclusion, patients in whom the start of treatment is delayed may demonstrate slightly reduced benefits as compared with those seen in patients starting donepezil therapy early in the course of Alzheimer's disease. These data support the long-term efficacy and safety of donepezil.

Clinical correlates of cognitive decline in vascular dementia

OBJECTIVE

To determine whether demographic data, dementia severity, functional status, whole brain volume (WBV), or subcortical hyperintensity volume (SH) predict subsequent cognitive decline in vascular dementia (VaD).

BACKGROUND

The identification of variables that accurately predict progressive cognitive decline in dementia has important clinical implications.

METHODS

A cohort of 30 patients with VaD completed neurologic and neuropsychologic examinations and magnetic resonance imaging of the brain at baseline and again after 12 months. All participants met clinical and research criteria for VaD according to standard guidelines. Change scores were computed for measures of verbal fluency, verbal learning, and visual learning. Potential correlates of cognitive change included age, education, score on the Hachinski scale, WBV, SH, and functional ability.

RESULTS

As a group, lower WBV and lower Hachinski score correlated with decline in verbal fluency and visual learning, whereas lower Hachinski score correlated with decline in verbal learning. However, when subdivided by disease type, this pattern held only for individuals with evidence of a cortical stroke at baseline. No clinical variables correlated with cognitive decline among individuals without a cortical infarction.

CONCLUSIONS

Assessment of cognitive decline in VaD should be guided by dementia subtype, with particular attention directed at severity of cerebral atrophy rather than classic symptoms of infarction.

Donepezil for Alzheimer's disease in clinical practice--The DONALD Study. A multicenter 24-week clinical trial in Germany

This multicenter open-label clinical trial was designed to investigate the safety and efficacy of donepezil, a selective acetylcholinesterase inhibitor, in the treatment of Alzheimer's disease (AD) in routine clinical practice in Germany. A total of 237 patients with mild-to-moderate AD were treated with donepezil for 24 weeks, 186 completed the study according to the protocol. In the completer group, mean MMSE score for efficacy showed an improvement from baseline of +1.6 points at week 12 (95% CI +1.1 to +2.1) and of +1.1 points at week 24 (95% CI +0.5 to +1.7). In more than 80% of the patients, global tolerability was rated to be very good or good. There were only insignificant effects on ECG parameters. This study confirms the results obtained in previous double-blind trials, which showed that donepezil is effective and well tolerated in patients with mild-to-moderately severe AD.

A randomized, double-blind, placebo-controlled study of the efficacy and safety of donepezil in patients with Alzheimer's disease in the nursing home setting

OBJECTIVES

To evaluate the safety and efficacy of donepezil in the management of patients with Alzheimer's disease (AD) residing in nursing home facilities.

DESIGN

Twenty-four-week, randomized, multicenter, parallel-group, double-blind, placebo-controlled trial.

SETTING

Twenty-seven nursing homes across the United States.

PARTICIPANTS

Two hundred eight nursing home patients with a diagnosis of probable or possible AD, or AD with cerebrovascular disease; mean Mini-Mental State Examination (MMSE) score 14.4; mean age 85.7.

MEASUREMENTS

The primary outcome measure was the Neuropsychiatric Inventory-Nursing Home Version (NPI-NH). Secondary efficacy measures were the Clinical Dementia Rating (Nursing Home Version)-Sum of the Boxes (CDR-SB), MMSE, and the Physical Self-Maintenance Scale (PSMS). Safety was monitored by physical examinations, vital signs, clinical laboratory tests, electrocardiograms (ECGs), and treatment-emergent adverse events (AEs).

RESULTS

Eighty-two percent of donepezil- and 74% of placebo-treated patients completed the trial. Eleven percent of donepezil- and 18% of placebo-treated patients withdrew because of AEs. Mean NPI-NH 12-item total scores improved relative to baseline for both groups, with no significant differences observed between the groups at any assessment. Mean change from baseline CDR-SB total score improved significantly with donepezil compared with placebo at Week 24 (P < .05). The change in CDR-SB total score was not influenced by age. Differences in mean change from baseline on the MMSE favored donepezil over placebo at Weeks 8, 16, and 20 (P < .05). No significant differences were observed between the groups on the PSMS. Overall rates of occurrence and severity of AEs were similar between the two groups (97% placebo, 96% donepezil). Gastrointestinal AEs occurred more frequently in donepezil-treated patients. In general, AEs were similar in older and younger donepezil-treated patients, with the majority of patients experiencing only AEs that were transient and mild or moderate in severity. Weight loss was reported as an AE more frequently in older patients, although a loss at last visit of >or=7% of screening weight occurred at the same rate in older and younger patients (9% of donepezil- and 6% of placebo-treated patients). No significant differences between groups in vital sign changes, bradycardia, or rates of clinically significant laboratory or ECG abnormalities were observed.

CONCLUSION

Patients treated with donepezil maintained or improved in cognition and overall dementia severity in contrast to placebo-treated patients who declined during the 6-month treatment period. The safety and tolerability profile was comparable with that reported in outpatient studies of donepezil. These findings also suggest that advanced age, comorbid illnesses, and high concomitant medication usage should not be barriers to donepezil treatment. Given the apparent improvement in behavior in the placebo group, and the high use of concomitant medications in both groups, the impact of donepezil on behavior in the nursing home setting is unresolved and merits further investigation. In summary, effects on cognition, overall dementia severity, and safety and tolerability findings are consistent with previous findings in outpatients and support the use of donepezil in patients with AD who reside in nursing homes.

A 1-year, randomized, placebo-controlled study of donepezil in patients with mild to moderate AD

OBJECTIVE

To evaluate the long-term clinical efficacy and safety of donepezil versus placebo over 1 year in patients with mild to moderate AD.

METHODS

Patients (n = 286; mean age, 72.5 years) with possible or probable AD from five Northern European countries were randomized to receive either donepezil (n = 142; 5 mg/day for 28 days, followed by 10 mg/day) or placebo (n = 144) for 1 year.

RESULTS

The study was completed by 66.9% of the donepezil- and 67.4% of the placebo-treated patients. The benefit of donepezil over placebo was demonstrated by the Gottfries-Bråne-Steen (a global assessment for rating dementia symptoms) total score at weeks 24, 36, and 52 (p < 0.05) and at the study end point (week 52, last observation carried forward; p = 0.054). Advantages of donepezil over placebo were also observed in cognition and activities of daily living (ADL) assessed by the Mini-Mental State Examination at weeks 24, 36, and 52, and the end point (p < 0.02) and by the Progressive Deterioration Scale at week 52 and the end point (p < 0.05). Adverse events (AE) were recorded for 81.7% of donepezil- and 75.7% of placebo-treated patients, with 7% of donepezil- and 6.3% of placebo-treated patients discontinuing because of AE. Treatment response to donepezil was not predicted by APOE genotype or sex in this population.

CONCLUSION

As the first 1-year, multinational, double-blinded, placebo-controlled study of a cholinesterase inhibitor in AD, these data support donepezil as a well tolerated and effective long-term treatment for patients with AD, with benefits over placebo on global assessment, cognition, and ADL.

The validity of informant report for grading the severity of Alzheimer's dementia

The validity of informant-based techniques has been established for the detection of dementia cases by non-pathological individuals, but is still controversial for the assessment of the severity of dementia. This study aimed at ascertaining whether informant-based evaluation (the so-called informant report) of the cognitive and behavioral impairment of a patient is valid for grading the severity of dementia, and consistent with objective assessment of the patient's cognitive and behavioral functioning. We enrolled 96 community-dwelling outpatients and 56 controls assessed at the Geriatric Evaluation Unit of the University of Modena, Italy. All patients scored lower than 27 on the MMSE, and met DSM-IV inclusion criteria for Alzheimer's dementia. Patients and controls were administered the CAMDEX interview, containing a section which collects participant (patient or control) and informant evaluations on dementia-related cognitive and behavioral deficits. The informant report resulted effective at MANOVA for grading the severity of dementia in 4 of its 5 measures (namely, memory, everyday activities, general mental functioning and depressed mood), and was correlated with the scores of several scales of the CAMDEX cognitive section (i.e., CAMCOG). Instead, the participant's (patient or control) report showed a lower capacity for grading dementia, and was poorly correlated with the psychometric outcomes of cognitive functioning. On the whole, the results corroborated the validity of the informant report in the diagnostic work-up for grading dementia, given its sensitivity to the severity of dementia, and its consistency with cognitive psychometric outcomes.

Modeling the time-course of Alzheimer dementia

Alzheimer's disease (AD) progresses from a preclinical period, through a middle phase of cognitive deterioration, to a late, profound state. The temporal progression of disability can be modeled with a horologic (time-based) function using "time-index" (TI) intervals (day- or year-units) to quantify an individual's disability across multiple cognitive and functional domains relative to a reference AD population. Clinicians and researchers can use TI quantification to assess dementia severity and initial therapy benefits. Rate of progression and confidence intervals require at least two successive measurements. Rate of progression measures can be used to support diagnosis and to investigate disease-course-modifying therapies.

Long-term efficacy and safety of donepezil in the treatment of Alzheimer's disease: final analysis of a US multicentre open-label study

This multicentre, open-label study evaluated the long-term efficacy and safety of donepezil in the treatment of patients with mild to moderately severe Alzheimer's disease (AD). The 133 patients who entered the study had previously completed a 14-week randomized, double-blind, placebo-controlled study with donepezil. In this open-label study, patients were treated initially with 3 mg per day donepezil, which could be increased to 5, 7 and 10 mg per day in a step-wise fashion. Patients attended the clinic for assessments at 3-week intervals for the first 12 weeks, then subsequently at 12-week intervals for up to 240 weeks (254 cumulative weeks). Efficacy was assessed using the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) and the Clinical Dementia Rating-Sum of the Boxes scale (CDR-SB), and data were compared with those predicted for historical untreated AD patients. During the first 6-9 months of the study, mean ADAS-cog and CDR-SB scores showed evidence of clinical improvement from baseline. After this time scores gradually deteriorated. Overall the decline was less than that estimated if this cohort of patients had not been treated. The most common adverse events were related to the nervous and digestive systems, and were generally mild and transient, resolving without the need for dose modifications. There was no evidence of hepatotoxicity. In conclusion, these data demonstrate that donepezil is a well-tolerated, realistic symptomatic treatment for AD over a period of up to 4.9 years. An interim report of the first 98 weeks of the study has been published previously.

Validation of the full and short forms of the CAMDEX interview for diagnosing dementia: evidence from a one-year follow-up study

The sensitivity and specificity of the two forms of the CAMDEX interview for dementia diagnosis were assessed in a 1-year follow-up study. At the beginning of the study, 60 patients (22 males and 38 females) who met DSM-IV criteria for dementia and 60 matched controls (15 males and 45 females), were administered the short form of the CAMDEX (short CAMDEX) 3 months after the full one (full CAMDEX). At the follow-up, all patients were administered both the full and short CAMDEX (again with a 3-month interval), whereas controls were administered either CAMDEX form (in any case, at a 12-month interval from initial testing). Upon initial testing, the sensitivity of the full CAMCOG proved to be significantly higher than that of the short CAMCOG, while the opposite trend was observed for specificity, that is the sensitivity of the full Organicity was lower than that of the short Organicity, with specificity remaining equal in the two forms. Upon follow-up, the specificity and sensitivity levels of the two forms did not significantly differ for the CAMCOG and Organicity indices. Moreover, in detecting mildly demented patients, the full CAMCOG proved to be more accurate than the short one, while the opposite trend was observed for Organicity. Among the dementia subjects, significant correlations were found between the homologous indices of the two forms for both test sessions. On the whole, the short CAMDEX appears to maintain most of the psychometric properties of the full version and therefore the two CAMDEX forms can be considered to be interchangeable.

Cognitive changes in very old persons with dementia: the influence of demographic, psychometric, and biological variables

Longitudinal changes in global cognitive functioning, indexed by the Mini-Mental State Examination (MMSE), in subjects with dementia (Alzheimer's disease and vascular dementia) were examined. The roles of several demographic, psychometric, and biological indices in predicting cognitive deterioration were also examined. The sample consisted of 36 very old (M age at entry = 83.0 years, range = 75-95) adults with dementia from a community-based study. Subjects were tested on two occasions separated by approximately 2.5 years. Results indicated significant longitudinal decline in MMSE scores over the retest interval; the average decline was estimated as 2.43 (SD = 1.81) points per year. Several factors were associated with cognitive deterioration. Higher initial MMSE scores were associated with greater deterioration, whereas superior forward digit span and Block Design at entry were associated with attenuated decline, once differences in baseline severity were accounted for. By contrast, a variety of other putatively important variables exhibited no relationship to decline, including age, gender, education, onset age, dementia type, backward digit span, as well as a number of biological parameters (e.g., vitamin B12, folic acid). The results suggest that although the magnitude of cognitive deterioration in dementia is highly variable, several indicators may be useful predictors of future changes in cognitive functioning.

Diagnosis of Alzheimer's disease: defining genetic profiles (genotype vs phenotype)

The early identification of Alzheimer's disease (AD) requires a multifactorial diagnostic approach. Components of a comprehensive assessment include a clinical examination, neuropsychological and psychometric evaluations, biochemical tests, cardiovascular and radiological examinations, neuroimaging, brain bioelectrical activity mapping, an evaluation of brain hemodynamics, and assessment of biological markers. Genetic testing should be incorporated into the diagnostic protocol only for research purposes and risk evaluation. The genetic characterization of familial AD genotypes (FAD-21, FAD-14, FAD-1, FAD-19, APP-21m) can help define the phenotypic profiles of AD clinical subtypes. The correlation of genotypic and phenotypic profiles might have a predictive value in terms of AD diagnosis and therapeutic responses to particular drugs. However, available genetic markers (APP-21m, APO-E) are not yet conclusive for diagnostic purposes. In contrast, AD-related Apo-E genotypes appear to correlate with defined AD phenotypes. The presence of an Apo-E4 allele seems to represent an important risk factor for dementia.

Longitudinal changes in cognitive functioning in adult day care participants

This study examines longitudinal changes in cognitive functioning over the course of 2 years in participants of adult day cae programs. Cognitive measures included the Brief Cognitive Rating Scale (BCRS) and the Mini-Mental State Examination (MMSE). Longitudinal data were available for five measurement points over 2 years for 82 participants (22 males and 60 females). Overall, results from this study suggest that there were significant cognitive declines on BCRS and MMSE, even after only 1 or 2 years in the study. The rates of impairment over the 2 years for BCRS and MMSE were highly correlated. Within each measure, the individual rates of decline were very heterogenous and were influenced by the presence, type, and prognosis of dementia. Participants with multi-infarct dementia had greater cognitive decline than did those with other types of dementias. Initial cognitive functioning and physician's prognosis of dementia trajectory were also significant predictors of change over time. Results suggest a floor effect in the BCRS.