Clinical features distinguishing large cohorts with possible AD, probable AD, and mixed dementia

Acetyl-cholinesterase-inhibitors reconsidered. A narrative review of post-marketing studies on Alzheimer's disease

The real efficacy of Acetyl-cholinesterase-inhibitors (AChEI) has been questioned. In this narrative review we evaluated their effect on cognitive decline, measured by Mini Mental State Examination (MMSE), and on total mortality rates in patients with Alzheimer's disease (AD) recruited into post-marketing open/non-randomized/retrospective studies. In AD patients treated with AChEI, the mean MMSE loss ranged from 0.2 to 1.37 points/years, compared with 1.07-3.4 points/years in non-treated patients. Six studies also reported data about survival; a reduction in total mortality relative risk between 27% and 42% was observed, over a period of 2-8 years. The type of studies and the use of MMSE to assess cognitive decline, may have introduced several biases. However, the clinical effects of AChEI seem to be of the same order of magnitude as the drugs currently used in most common chronic disorders, as regards progression of the disease and total mortality. In the absence of long-term randomized trials on "standard" unselected AD outpatients, open/retrospective studies and health databases represent the best available evidence on the possible effect of AChEI in the real-word setting. Our data support the clinical benefit of AChEI in older patients affected by AD.

Neuropsychological differential diagnosis of Alzheimer's disease and vascular dementia: a systematic review with meta-regressions

Introduction

Diagnostic classification systems and guidelines posit distinguishing patterns of impairment in Alzheimer's (AD) and vascular dementia (VaD). In our study, we aim to identify which diagnostic instruments distinguish them.

Methods

We searched PubMed and PsychInfo for empirical studies published until December 2020, which investigated differences in cognitive, behavioral, psychiatric, and functional measures in patients older than 64 years and reported information on VaD subtype, age, education, dementia severity, and proportion of women. We systematically reviewed these studies and conducted Bayesian hierarchical meta-regressions to quantify the evidence for differences using the Bayes factor (BF). The risk of bias was assessed using the Newcastle-Ottawa-Scale and funnel plots.

Results

We identified 122 studies with 17,850 AD and 5,247 VaD patients. Methodological limitations of the included studies are low comparability of patient groups and an untransparent patient selection process. In the digit span backward task, AD patients were nine times more probable (BF = 9.38) to outperform VaD patients (β g = 0.33, 95% ETI = 0.12, 0.52). In the phonemic fluency task, AD patients outperformed subcortical VaD (sVaD) patients (β g = 0.51, 95% ETI = 0.22, 0.77, BF = 42.36). VaD patients, in contrast, outperformed AD patients in verbal (β g = -0.61, 95% ETI = -0.97, -0.26, BF = 22.71) and visual (β g = -0.85, 95% ETI = -1.29, -0.32, BF = 13.67) delayed recall. We found the greatest difference in verbal memory, showing that sVaD patients outperform AD patients (β g = -0.64, 95% ETI = -0.88, -0.36, BF = 72.97). Finally, AD patients performed worse than sVaD patients in recognition memory tasks (β g = -0.76, 95% ETI = -1.26, -0.26, BF = 11.50).

Conclusion

Our findings show inferior performance of AD in episodic memory and superior performance in working memory. We found little support for other differences proposed by diagnostic systems and diagnostic guidelines. The utility of cognitive, behavioral, psychiatric, and functional measures in differential diagnosis is limited and should be complemented by other information. Finally, we identify research areas and avenues, which could significantly improve the diagnostic value of cognitive measures.

Modifiable, Non-Modifiable, and Clinical Factors Associated with Progression of Alzheimer's Disease

There is an extensive literature relating to factors associated with the development of Alzheimer's disease (AD), but less is known about factors which may contribute to its progression. This review examined the literature with regard to 15 factors which were suggested by PubMed search to be positively associated with the cognitive and/or neuropathological progression of AD. The factors were grouped as potentially modifiable (vascular risk factors, comorbidities, malnutrition, educational level, inflammation, and oxidative stress), non-modifiable (age at clinical onset, family history of dementia, gender, Apolipoprotein E ɛ4, genetic variants, and altered gene regulation), and clinical (baseline cognitive level, neuropsychiatric symptoms, and extrapyramidal signs). Although conflicting results were found for the majority of factors, a positive association was found in nearly all studies which investigated the relationship of six factors to AD progression: malnutrition, genetic variants, altered gene regulation, baseline cognitive level, neuropsychiatric symptoms, and extrapyramidal signs. Whether these or other factors which have been suggested to be associated with AD progression actually influence the rate of decline of AD patients is unclear. Therapeutic approaches which include addressing of modifiable factors associated with AD progression should be considered.

Mixed dementia: Neglected clinical entity or nosographic artifice?

Clinical and pathological data show that Alzheimer's disease (AD) and vascular dementia (VaD) are the most prevalent types of dementia in the elderly. Medically speaking, mixed dementia (MxD) is a heterogenous disorder mostly referred to the coexistence of AD and VaD. The weight of vascular contribution to AD phenotype is nowadays matter of debate. Despite great efforts in the field of neurodegeneration and cerebrovascular disease, controversy over the exact nature of their relation still remains, hampering progress in the specialty and raising doubts about the MxD concept validity. Is MxD a neglected clinical entity or a nosographic artifice? Starting from the assumption that recent advances in dementia classification and diagnostic criteria make this a propitious time to set up preventive and therapeutic strategies, this narrative review and opinion paper summarizes the literature concerning the questioned etiopathogenic overlap between AD and VaD and challenges the traditional view of MxD as the mere co-occurrence of different pure forms of dementia.

Biomarker clusters are differentially associated with longitudinal cognitive decline in late midlife

The ability to detect preclinical Alzheimer's disease is of great importance, as this stage of the Alzheimer's continuum is believed to provide a key window for intervention and prevention. As Alzheimer's disease is characterized by multiple pathological changes, a biomarker panel reflecting co-occurring pathology will likely be most useful for early detection. Towards this end, 175 late middle-aged participants (mean age 55.9 ± 5.7 years at first cognitive assessment, 70% female) were recruited from two longitudinally followed cohorts to undergo magnetic resonance imaging and lumbar puncture. Cluster analysis was used to group individuals based on biomarkers of amyloid pathology (cerebrospinal fluid amyloid-β42/amyloid-β40 assay levels), magnetic resonance imaging-derived measures of neurodegeneration/atrophy (cerebrospinal fluid-to-brain volume ratio, and hippocampal volume), neurofibrillary tangles (cerebrospinal fluid phosphorylated tau181 assay levels), and a brain-based marker of vascular risk (total white matter hyperintensity lesion volume). Four biomarker clusters emerged consistent with preclinical features of (i) Alzheimer's disease; (ii) mixed Alzheimer's disease and vascular aetiology; (iii) suspected non-Alzheimer's disease aetiology; and (iv) healthy ageing. Cognitive decline was then analysed between clusters using longitudinal assessments of episodic memory, semantic memory, executive function, and global cognitive function with linear mixed effects modelling. Cluster 1 exhibited a higher intercept and greater rates of decline on tests of episodic memory. Cluster 2 had a lower intercept on a test of semantic memory and both Cluster 2 and Cluster 3 had steeper rates of decline on a test of global cognition. Additional analyses on Cluster 3, which had the smallest hippocampal volume, suggest that its biomarker profile is more likely due to hippocampal vulnerability and not to detectable specific volume loss exceeding the rate of normal ageing. Our results demonstrate that pathology, as indicated by biomarkers, in a preclinical timeframe is related to patterns of longitudinal cognitive decline. Such biomarker patterns may be useful for identifying at-risk populations to recruit for clinical trials.

Hypertension in patients with Alzheimer's disease--prevalence, characteristics, and impact on clinical outcome. Experience of one neurology center in Poland

The aim of the study was to evaluate hypertension (HT) prevalence, characteristics, and impact on clinical outcome in patients with Alzheimer's disease (AD). We evaluated 701 patients with AD (249 males, 452 females, and mean age 74.9 ± 7.5 years). As a group representing general population matched with regard to age, education level, and place of residence, we included 762 subjects (438 males, 324 females, and mean age 74.7 ± 4.4 years) from the Polish National Multicenter Health Survey (WOBASZ) studies. The patients with AD were characterized by lower systolic blood pressure (BP) and diastolic BP values (134 ± 21 vs. 151 ± 23 mm Hg, P < .001 and 77 ± 11 vs. 86 ± 12 mm Hg, P < .001, respectively) as well as lower HT prevalence (66% vs. 78.6%, P < .001) compared with the WOBASZ group. In long-term follow-up of AD group, HT and BP levels were not associated with the decline in cognitive functions nor the increased risk of death. Patients with AD were characterized by lower prevalence of HT and other vascular risk factors. BP levels and HT had no impact on clinical outcome.

Effects of co-existent cerebrovascular disease on rate of progression in Alzheimer's disease

Objective: The aim of this study was to determine whether patients with possible Alzheimer's disease (AD) who do not meet criteria for vascular dementia but who nonetheless have clinical or radiographic evidence of cerebrovascular disease (CVD), differ in presentation or rate of progression from patients with probable AD.

Method: Baseline cognitive and functional scores were obtained from 154 patients who had either possible or probable AD. Repeat data after a 12 month interval were obtained on 73 of these patients. Baseline data and rates of progression were compared for probable AD patients and possible AD patients with evidence of co-existent CVD.

Results: The diagnostic groups did not differ at baseline with a mean mini-mental state examination (MMSE) score of 18.1. Comparison of the longitudinal data showed a mean annual drop of 4.1 points on the MMSE in both groups.

Conclusions: The patients with and without evidence of co-existent CVD did not differ either at baseline or prognostically suggesting that evidence of CVD does not affect the rate of progression in AD. However, further longitudinal studies using neuropathological criteria are warranted to determine whether such data can be interpreted in favour of including possible AD cases in clinical trials of probable AD.

Follow-up of loci from the International Genomics of Alzheimer's Disease Project identifies TRIP4 as a novel susceptibility gene

To follow-up loci discovered by the International Genomics of Alzheimer's Disease Project, we attempted independent replication of 19 single nucleotide polymorphisms (SNPs) in a large Spanish sample (Fundació ACE data set; 1808 patients and 2564 controls). Our results corroborate association with four SNPs located in the genes INPP5D, MEF2C, ZCWPW1 and FERMT2, respectively. Of these, ZCWPW1 was the only SNP to withstand correction for multiple testing (P=0.000655). Furthermore, we identify TRIP4 (rs74615166) as a novel genome-wide significant locus for Alzheimer's disease risk (odds ratio=1.31; confidence interval 95% (1.19-1.44); P=9.74 × 10(-)(9)).

Clinicopathologic study of Alzheimer's disease: Alzheimer mimics

A definite diagnosis of Alzheimer's disease (AD) can only be made at autopsy. Even at expert research centers, diagnostic accuracy is relatively low. We conducted this study to examine the accuracy of clinical diagnosis of AD and present a list of clinical and neuropsychological findings that could render the clinical diagnosis difficult. Using the National Alzheimer's Coordinating Center database, the records of 533 patients who had been diagnosed clinically with AD, and later underwent autopsy, were reviewed retrospectively. Since the pathologic results of 119 subjects did not meet the criteria for definite AD, we labeled them as Alzheimer "mimics". The neuropathological diagnoses of Alzheimer mimics consisted of dementia with Lewy bodies (n = 35, 29%), insufficient AD (n = 22, 18%), vascular disease (n = 15, 13%), frontotemporal lobar degeneration (n = 14, 12%), and hippocampal sclerosis (n = 10, 8%). History of pacemaker insertion (10.92% versus 4.11%, p = 0.005), congestive heart failure (13.45% versus 6.04%, p = 0.007), hypertension (56.30% versus 47.83%, p = 0.037), and resting tremor (14.29% versus 10.87%, p = 0.170) was more prevalent in Alzheimer mimics. Clinical Dementia Rating score and frequency of Neuropsychiatric Inventory Questionnaire items reflecting delusions, agitation, depression, and motor disturbance were more severe in confirmed AD. In addition to Mini-Mental State Examination (16.97 ± 8.29 versus 12.74 ± 15.26, p < 0.001), Logical Memory, Animal Fluency, Boston Naming Test, and Digit Span scores showed more severe impairment in confirmed AD. Continuing systematic comparisons of the current criteria for the clinical and pathological dementia diagnoses are essential to clinical practice and research, and may also lead to further improvement of the diagnostic procedure.

Association between functional impairment, depression, and extrapyramidal signs in neuroleptic-free patients with Alzheimer disease

BACKGROUND

Extrapyramidal signs (EPSs) are commonly observed in patients with Alzheimer disease (AD). We report here the base rate of EPS in a large cohort of patients with AD who were not receiving neuroleptic drugs, and the associations of EPS with functional outcomes and depressive symptoms.

METHODS

In a consortium involving 56 clinics, we recruited 2614 patients with AD. We estimated basic activities of daily living (ADL) and instrumental ADL by the Barthel index and the Seoul-Instrumental Activities of Daily Living (S-IADL) scales, respectively. Depressive symptoms were assessed using the 15-item Geriatric Depression Scale (GDS-15). The EPS group was defined by the presence of at least 1 EPS based on a focused neurologic examination.

RESULTS

The prevalence of EPS-positive patients was 12%. These had lower Korean version of the Mini-Mental State Examination (K-MMSE) scores than the EPS-negative cases (P < .001). After controlling for demographic, medical, radiological, genetic, and cognitive (K-MMSE) factors, the proportion of patients with impaired ADL was significantly higher in the EPS group than in the non-EPS group (P < .001, odds ratio = 1.90, 95% confidence interval, 1.45-2.48, and logistic regression). The S-IADL scores were significantly higher in the EPS group than this in the non-EPS group (P < .001, regression coefficient = 3.19, and median regression). The GDS-15 scores were higher in the EPS group (P = .04, regression coefficient = 0.89, and median regression).

CONCLUSION

The presence of EPS in patients with AD who were not receiving neuroleptic drugs was associated with more impaired basic and instrumental ADL functioning and with greater depression symptoms.

Progression of cognitive, functional, and neuropsychiatric symptom domains in a population cohort with Alzheimer dementia: the Cache County Dementia Progression study

OBJECTIVES

Progression of Alzheimer dementia (AD) is highly variable. Most estimates derive from convenience samples from dementia clinics or research centers where there is substantial potential for survival bias and other distortions. In a population-based sample of incident AD cases, we examined progression of impairment in cognition, function, and neuropsychiatric symptoms, and the influence of selected variables on these domains.

DESIGN

Longitudinal, prospective cohort study.

SETTING

Cache County (Utah).

PARTICIPANTS

Three hundred twenty-eight persons with a diagnosis of possible/probable AD.

MEASUREMENTS

Mini-Mental State Exam (MMSE), Clinical Dementia Rating sum-of-boxes (CDR-sb), and Neuropsychiatric Inventory (NPI).

RESULTS

Over a mean follow-up of 3.80 (range: 0.07-12.90) years, the mean (SD) annual rates of change were -1.53 (2.69) scale points on the MMSE, 1.44 (1.82) on the CDR-sb, and 2.55 (5.37) on the NPI. Among surviving participants, 30% to 58% progressed less than 1 point per year on these measures, even 5 to 7 years after dementia onset. Rates of change were correlated between MMSE and CDR-sb (r = -0.62, df = 201, p < 0.001) and between the CDR-sb and NPI (r = 0.20, df = 206, p < 0.004). Female subjects (LR χ = 8.7, df = 2, p = 0.013) and those with younger onset (likelihood ratio [LR] χ = 5.7, df = 2, p = 0.058) declined faster on the MMSE. Although one or more apolipoprotein E ε 4 alleles and ever use of FDA-approved antidementia medications were associated with initial MMSE scores, neither was related to the rate of progression in any domain.

CONCLUSIONS

A significant proportion of persons with AD progresses slowly. The results underscore differences between population-based versus clinic-based samples and suggest ongoing need to identify factors that may slow the progression of AD.

Management of mixed dementia

Alzheimer's disease (AD) and vascular dementia (VaD) are the most common causes of dementia in the elderly. Although AD can be diagnosed with a considerable degree of accuracy, the distinction between isolated AD, VaD and mixed dementia (MD) [when both pathologies coexist in the same patient] remains a controversial issue and one of the most difficult diagnostic challenges. MD represents a very common pathology, especially in the elderly, as reported in neuropathological studies. Accurate diagnosis of MD is of crucial significance for epidemiological purposes and for preventive and therapeutic strategies. Until recently, pharmacological studies have generally focused on pure disease, either AD or VaD, and have provided few data on the best therapeutic approach to MD. There is only one original randomized clinical trial on (acetyl)cholinesterase inhibitor therapy (GAL-INT-6, galantamine) for MD; the other studies are post hoc analyses of AD trial subgroups (AD2000, donepezil) or of VaD trial subgroups (VantagE, rivastigmine). Cholinesterase inhibitors have reproducible beneficial effects on cognitive and functional outcomes in patients with MD. These benefits are of a similar magnitude to those previously reported for the treatment of AD. It is likely that the beneficial effects of memantine (an NMDA receptor antagonist) in AD may also apply to MD, but randomized controlled trials are still lacking. Treatment of cardiovascular risk factors, especially hypertension, may protect brain function and should be included in prevention strategies for MD.

Bias in Markov models of disease

We examine bias in Markov models of diseases, including both chronic and infectious diseases. We consider two common types of Markov disease models: ones where disease progression changes by severity of disease, and ones where progression of disease changes in time or by age. We find sufficient conditions for bias to exist in models with aggregated transition probabilities when compared to models with state/time dependent transition probabilities. We also find that when aggregating data to compute transition probabilities, bias increases with the degree of data aggregation. We illustrate by examining bias in Markov models of Hepatitis C, Alzheimer's disease, and lung cancer using medical data and find that the bias is significant depending on the method used to aggregate the data. A key implication is that by not incorporating state/time dependent transition probabilities, studies that use Markov models of diseases may be significantly overestimating or underestimating disease progression. This could potentially result in incorrect recommendations from cost-effectiveness studies and incorrect disease burden forecasts.

[Vascular dementia and mixed dementia]

The concept of vascular dementia has evolved over the past century to include multiple underlying pathophysiological mechanisms. Neuroimaging techniques offer new and better ways to identify the presence of cerebrovascular pathology, although they do not improve our ability to link these changes to the onset of clinical cognitive impairment. Clinical criteria for vascular dementia have also evolved but they remain imperfect. Most epidemiological studies define mixed dementia as the coexistence of Alzheimer's disease and vascular dementia. Clinicopathologic correlations show a clear association between the concomitant presence of vascular and Alzheimer lesions and the severity of cognitive impairment in mixed dementia and provide strong support for the validity of the mixed dementia concept. Mixed dementia is a very frequent disease that remains underdiagnosed, especially in the elderly. The diagnosis of vascular and mixed dementia remains a clinical challenge and cannot be improved without further studies of clinicopathological correlations and functional neuroimaging. Preventive therapeutic interventions include control of vascular risk factors and especially treatment of hypertension.

[Alzheimer's disease: cardiovascular risk factors must be assessed]

BACKGROUND

Dementia is nowadays of major importance in public health. Alzheimer's disease and vascular cognitive impairments are its main aetiology in the elderly. The cause of Alzheimer's disease remains unknown. The factor initiating the physiopathology of this neurodegenerative disease is source of controversy.

CURRENT KNOWLEDGE AND KEY POINTS

The theory of a neurotoxicity initiated by amyloid deposition is questioned. A growing number of data suggest a central role of cardiovascular risk factors and alteration of arterial walls, inducing chronic brain hypoperfusion, as the primary trigger in the physiopathology of the disease. These data are based on epidemiological, physiopathological, neuroimaging, neuropathological and pharmacological studies. However, the exact link between arteriosclerosis, vascular cognitive impairment and Alzheimer's disease remains controversial.

FUTURE PROSPECTS AND PROJECTS

These debates point out the crucial importance of the assessment of cardiovascular risk factors, as a preventable cause, either of cognitive decline, morbidity and mortality. In this aim, major targets could be different when primary or secondary prevention are at stake. These controversies also suggest new research directions towards Alzheimer's disease physiopathology, and for pharmacological interventions aimed on the prevention of cognitive decline or the curative treatment for this disease.

Motor signs predict poor outcomes in Alzheimer disease

OBJECTIVE

To examine whether the presence of motor signs has predictive value for important outcomes in Alzheimer disease (AD).

METHODS

A total of 533 patients with AD at early stages (mean Folstein Mini-Mental State Examination [MMSE] 21/30 at entry) were recruited and followed semiannually for up to 13.1 years (mean 3) in five University-based AD centers in the United States and European Union. Four outcomes, assessed every 6 months, were used in Cox models: cognitive endpoint (Columbia Mini-Mental State Examination < or = 20/57 [ approximately MMSE < or = 10/30]), functional endpoint (Blessed Dementia Rating Scale > or = 10), institutionalization equivalent index, and death. Using a standardized portion of the Unified PD Rating Scale (administered every 6 months for a total of 3,149 visit-assessments, average 5.9 per patient), the presence of motor signs, as well as of individual motor sign domains, was examined as time-dependent predictor. The models controlled for cohort, recruitment center, sex, age, education, a comorbidity index, and baseline cognitive and functional performance.

RESULTS

A total of 39% of the patients reached the cognitive, 41% the functional, 54% the institutionalization, and 47% the mortality endpoint. Motor signs were noted for 14% of patients at baseline and for 45% at any evaluation. Their presence was associated with increased risk for cognitive decline (RR, 1.72; 95% CI, 1.24 to 2.38), functional decline (1.80 [1.33 to 2.45]), institutionalization (1.68 [1.26 to 2.25]), and death (1.38 [1.05 to 1.82]). Tremor was associated with increased risk for reaching the cognitive and bradykinesia for reaching the functional endpoints. Postural-gait abnormalities carried increased risk for institutionalization and mortality. Faster rates of motor sign accumulation were associated with increased risk for all outcomes.

CONCLUSIONS

Motor signs predict cognitive and functional decline, institutionalization, and mortality in Alzheimer disease. Different motor sign domains predict different outcomes.

Delusions and hallucinations are associated with worse outcome in Alzheimer disease

BACKGROUND

Delusions and hallucinations are common in Alzheimer disease (AD) and there are conflicting reports regarding their ability to predict cognitive decline, functional decline, and institutionalization. According to all previous literature, they are not associated with mortality.

OBJECTIVE

To examine whether the presence of delusions or hallucinations has predictive value for important outcomes in AD.

DESIGN, SETTING, AND PARTICIPANTS

A total of 456 patients with AD at early stages (mean Folstein Mini-Mental State Examination [MMSE] score of 21 of 30 at entry) were recruited and followed up semiannually for up to 14 years (mean, 4.5 years) in 5 university-based AD centers in the United States and Europe. Using the Columbia University Scale for Psychopathology in AD (administered every 6 months, for a total of 3266 visit-assessments, average of 7.2 per patient), the presence of delusions and hallucinations was extracted and examined as time-dependent predictors in Cox models. The models controlled for cohort effect, recruitment center, informant status, sex, age, education, a comorbidity index, baseline cognitive and baseline functional performance, behavioral symptoms, and use of neuroleptics and cholinesterase inhibitors.

MAIN OUTCOME MEASURES

Cognitive (Columbia MMSE score of < or =20/57 [approximate Folstein MMSE score of < or =10/30]), functional (Blessed Dementia Rating Scale [parts I and II] score of > or =10), institutionalization equivalent index, and death.

RESULTS

During the full course of follow-up, 38% of patients reached the cognitive, 41% the functional, 54% the institutionalization, and 49% the mortality end point. Delusions were noted for 34% of patients at baseline and 70% at any evaluation. Their presence was associated with increased risk for cognitive (risk ratio [RR], 1.50; 95% confidence interval [CI], 1.07-2.08) and functional decline (RR, 1.41; 95% CI, 1.02-1.94). Hallucinations were present in 7% of patients at initial visit and in 33% at any visit. Their presence was associated with increased risk for cognitive decline (RR, 1.62; 95% CI, 1.06-2.47), functional decline (RR, 2.25; 95% CI, 1.54-2.27), institutionalization (RR, 1.60; 95% CI, 1.13-2.28), and death (RR, 1.49; 95% CI, 1.03-2.14).

CONCLUSIONS

Delusions and hallucinations are very common in AD and predict cognitive and functional decline. Presence of hallucinations is also associated with institutionalization and mortality.

Progress in clinical neurosciences: cognitive markers of progression in Alzheimer's disease

The objective of this review is to summarize the literature on Alzheimer's disease progression utilizing cognitive batteries to track change over time. Studies published in English and obtained through PubMed searches (1983-2004) were included (i) if they had a longitudinal design and followed probable Alzheimer's patients diagnosed by National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association or Diagnostic and Statistical Manual III/IV criteria, and (ii) if the techniques used for serial assessment were well-established in terms of validity and reliability. Longitudinal studies examining Alzheimer's disease progression report highly variable annual rates of change in decline rate. It remains unclear if this reflects disease subgroups or stage-related rate of decline. In conclusion a combination of stage-appropriate cognitive tests such as the Mattis Dementia Rating Scale and the Severe Impairment Battery, along with appropriate statistical methods to account for individual variability in decline rates, can capture the progression of Alzheimer disease and may be useful in further investigation.

[18F]FDG-PET in patients with Alzheimer's disease: marker of disease spread

BACKGROUND

It is not known yet whether temporoparietal glucose hypometabolism in patients with probable Alzheimer's disease (AD) reflects disease severity or different subtypes of patients.

METHODS

Twenty-five subjects with mild probable AD [NINCDS-ADRDA criteria; age 65.8 +/- 9.3 years (mean +/- SD); Mini-Mental State Examination (MMSE) 26.0 +/- 3.3] were investigated. [(18)F]FDG-PET data were analyzed visually with raters blinded to the diagnosis and with a quantitative analysis in the region of interest on individual anatomically normalized PET scans.

RESULTS

Thirteen of 25 patients showed temporoparietal hypometabolism on visual inspection (PET+; age 65.7 +/- 10.7), 12 patients had normal FDG-PET results (PET-; age 65.9 +/- 8.0; n.s.). The MMSE and immediate reproduction of the Wechsler Memory Scale (WMS-R-I) were 27.7 +/- 1.9 and 31.1 +/- 6.1 in the PET- vs. 24.5 +/- 3.6 (p = 0.012) and 22.0 +/- 7.4 (p = 0.006) in the PET+ group. Immediate and delayed recall in the California Verbal Learning Test and delayed reproduction in the Wechsler Memory Scale were alike. Regression analysis revealed a significant correlation of temporoparietal glucose metabolism with the block span (r = 0.60; p < 0.01) and the WMS-R-I (r = 0.68; p < 0.01) but not with measures of hippocampal function.

CONCLUSIONS

Temporoparietal glucose metabolism in patients with very mild AD is a sign of disease spread beyond the temporal lobe. This may aid in establishing objective parameters for future therapeutic studies.

Alzheimer's disease with and without cerebral infarcts

OBJECTIVE

To compare the clinical and pathological features of Alzheimer's disease (AD) patients with and without associated cerebral infarcts (CI).

METHODS

The consecutive records of 57 prospectively studied demented patients fulfilling the CERAD criteria for the pathological diagnosis of AD were reviewed. Cases with cortical Lewy bodies were excluded. CI were found in 22 cases (39%) (AD+CI group): large infarcts (5), lacunes (13) and/or hippocampal sclerosis (4), and were absent in 35 cases (AD group). Microscopic infarcts, cribiform change, amyloid angiopathy, and white matter rarefaction were not considered in this classification, but were quantified. Cortical atrophy, neurofibrillary tangle and senile plaque (diffuse and neuritic) load were also measured. Pathological evaluation was independent of clinical information. Clinical and pathological data were compared between both groups.

RESULTS

AD+CI cases were significantly older, more commonly female, less educated, and more often had blue collar occupations, sleep disturbances, frontal release signs, and EEG spikes than AD cases. Other differences found (acute/subacute onset, behavioral disturbances, and leukoaraiosis on CT scan) disappeared after controlling for age. The frequency of known vascular risk factors and focal motor and sensory signs did not differ between the groups, which showed remarkable clinical similarity overall. The only significant differences on pathological exam were hippocampal microinfarcts and white matter lesions, although there was a trend for lower neurodegenerative lesion load in the AD+CI group. The ischemic lesions were located in temporal lobe in 50% of AD+CI patients; these cases had a significantly lower neocortical neurodegenerative lesion load than those with CI in other sites.

CONCLUSIONS

The presence of CI in AD increases significantly with age, but has scarce influence on the clinical features, and cannot be predicted from common vascular risk factors. In spite of a trend, there are no major differences in neurodegenerative lesion load between AD and AD+CI groups, except when CI are located in the temporal lobe (including hippocampus), suggesting that this location may be important in the physiopathology of mixed vascular and AD dementia.

Improvement of weight and fat-free mass with oral nutritional supplementation in patients with Alzheimer's disease at risk of malnutrition: a prospective randomized study

OBJECTIVES

To study the effects of oral nutritional supplements (OS) on body weight, body composition, nutritional status, and cognition in elderly patients with Alzheimer's disease (AD).

DESIGN

Prospective, randomized, controlled study.

SETTING

Geriatric wards and day care centers in the Toulouse area, France.

PARTICIPANTS

Ninety-one subjects with AD aged 65 and older at risk of undernutrition as evaluated using the Mini Nutritional Assessment.

INTERVENTION

After randomization, 46 patients (intervention group) received 3-month OS. The other 45 patients (control group) received usual care.

MEASUREMENTS

Weight, body composition (evaluated using dual-energy x-ray absorptiometry), cognitive function, activities of daily living, eating behavior, and dietary intakes were evaluated at the beginning of the study and at 3 months and 6 months. Supplement compliance was recorded each day.

RESULTS

Between baseline and 3 months, energy and protein intakes significantly improved in the intervention group, resulting in a significant increase in weight and fat-free mass, but no significant changes were found for dependence, cognitive function, or biological markers. The nutritional benefit was maintained in the intervention group after discontinuation of OS at 3 months.

CONCLUSION

Three-month daily OS significantly improves body weight. It is practicable and effective, and the patients accepted it well. The improvement that was observed even in the control group showed that caregiver education is an important factor in maintaining the nutritional status of patients with AD. Moreover, regular courses of OS may help to maintain the increase in fat-free mass and improve the nutritional status of these patients.

Ovarian hormones and cognition in the aged female rat: I. Long-term, but not short-term, ovariectomy enhances spatial performance

Although research suggests that ovariectomy (ovx) is detrimental to spatial cognition in young rats, little work has evaluated the cognitive effects of ovx in aged rats. The authors investigated the effects of ovx in aged rats using the water radial-arm maze. In Study 1, young rats and aged rats receiving ovx 1.5 months before testing outperformed aged rats receiving sham surgery or ovx 21 days before testing. In Study 2, young rats and aged rats receiving ovx 2.0 or 6.0 months before testing outperformed aged sham rats. Aged rats exhibited estradiol and elevated progesterone levels comparable to those of young rats. The findings suggest that 1.5-6.0 months, but not 21 days, of ovx improves spatial memory in aged rats. The hypothesis that long-term ovarian hormone loss is detrimental to spatial memory in aged rats was not supported. The authors hypothesize that removal of elevated progesterone levels is related to the ovx-induced cognitive enhancement.

Mixed dementia: Alzheimer's and cerebrovascular disease

"Mixed dementia" is traditionally defined as Alzheimer's disease with cerebrovascular disease (CVD). Because the risks of both neurodegenerative dementias and cerebrovascular disease increase with age, the mixed dementias are likely the most common. In practice, patients with mixed dementia are diagnosed by one of two routes: Either they have evidence of a neurodegenerative dementia and CVD at the outset, or, they have a classical neurodegenerative presentation but are found to have ischemic lesions by neuroimaging. These facts have implications for the development of evidence-based diagnostic criteria.

Which factors influence cognitive decline in older adults suffering from dementing disorders?

BACKGROUND

Although extensive research has been done on dementing disorders in recent decades, their natural course and prognosis are not yet well understood. The aim of our study was to assess cognitive decline in a representative sample of demented elderly and to analyse the predictive value of a broad spectrum of sociodemographic, neurological and clinical variables.

METHODS

A random sample of elderly patients in primary care (n = 407) was drawn from a total of 3721 patients. The sample has been stratified according to the degree of cognitive impairment as assessed by their GPs. The patients were examined by means of a standardized research interview, including comprehensive cognitive testing (Hierarchic Dementia Scale) and the assessment of neurologic and physical impairments as well as of mental state (CAMDEX criteria). After a mean interval of 28 months, a follow-up study was conducted using essentially the same instruments.

RESULTS

At baseline, 117 of the 407 patients were identified as suffering from mild, moderate, or severe dementia. The two-year follow-up of those patients revealed high mortality rates (53/117). The surviving patients showed significant cognitive decline, although the rate varied considerably between individuals. The rate of progression was strongly related to the initial degree of severity, but also to the use of psychotropic medication, which was associated with a more rapid deterioration.

CONCLUSIONS

There are some prognostic indicators that can help to establish the prognosis for dementia patients. The best indicator for both--the rate of cognitive decline and the probability of survival--is the severity of dementia.

Volumetric MRI predicts rate of cognitive decline related to AD and cerebrovascular disease

OBJECTIVE

To examine volumetric MRI correlates of longitudinal cognitive decline in normal aging, AD, and subcortical cerebrovascular brain injury (SCVBI).

BACKGROUND

Previous cross-sectional studies examining the relationship between cognitive impairment and dementia have shown that hippocampal and cortical gray matter atrophy are the most important predictors of cognitive impairment, even in cases with SCVBI. The authors hypothesized that hippocampal and cortical gray matter volume also would best predict rate of cognitive decline in cases with and without SCVBI.

METHODS

Subjects were recruited for a multicenter study of contributions to dementia of AD and SCVBI. The sample (n = 120) included cognitively normal, cognitively impaired, and demented cases with and without lacunes identified by MRI. Cases with cortical strokes were excluded. Average length of follow-up was 3.0 years. Measures of hippocampal volume, volume of cortical gray matter, presence of subcortical lacunes, and volume of white matter hyperintensity were derived from MRI. Random effects modeling of longitudinal data was used to assess effects of baseline MRI variables on longitudinal change in a measure of global cognitive ability.

RESULTS

Cortical gray matter atrophy predicted cognitive decline regardless of whether lacunes were present. Hippocampal atrophy predicted decline only in those without lacunes. Neither lacunes nor white matter hyperintensity independently predicted decline.

CONCLUSIONS

Results suggest that cortical atrophy is an index of disease severity in both AD and subcortical cerebrovascular brain injury and consequently predicts faster progression. Hippocampal volume may index disease severity and predict progression in AD. The absence of this effect in cases with lacunes suggests that this group is etiologically heterogeneous and is not composed simply of cases of AD with incidental stroke.

Mixed dementia: epidemiology, diagnosis, and treatment

Alzheimer's disease (AD) and vascular dementia (VaD) are the most frequent causes of dementia in older people. Although AD can be diagnosed with a considerable degree of accuracy, the distinction between isolated AD, VaD, and mixed dementia (MD), where both pathologies coexist in the same patient, remains a controversial issue and one of the most difficult diagnostic challenges. Although MD represents a very frequent pathology, especially in older people, as reported in neuropathological studies, the respective importance of degenerative and vascular lesions, their interaction in the genesis of dementia, and the mere existence of MD are still debated. Accurate diagnosis of MD is of crucial significance for epidemiological purposes and for preventive and therapeutic strategies. Until recently, pharmacological studies have generally focused on pure disease, AD or VaD, and have provided little information on the best therapeutic approach to MD. This article provides an overview of MD in older people. A retrospective review of the recent literature on prevalence, incidence, course, risk factors, diagnosis, and treatment of MD was performed. The article also emphasizes the need for further studies, including neuropsychological and functional evaluations, and neuroimaging and clinicopathological correlations to develop a better understanding of MD, which appears to be one of the most common forms of dementia.

Optimization of techniques for the maximal detection and quantification of Alzheimer's-related neuropathology with digital imaging

Prior to undertaking quantitative neuropathological studies of Alzheimer's disease, methods for detecting plaques and tangles must be optimized. While suitable antibodies have been developed with great sensitivity, specificity, and reliability, there is no standard pre-treatment protocol for key AD-related pathology. It is well known that formic acid treatment enhances the detection of beta-amyloid. But what concentration of formic acid is best; can similar methods enhance the detection of tau-related pathology? This study compared multiple antigen retrieval techniques (e.g. boiling in citrate or glycine buffer, microwaves, formic acid concentrations), to develop an optimal, standardized protocol for quantitative digital microscopy. Free-floating (40 microm) and paraffin-embedded (12 microm) sections of formalin fixed frontal cortex from mild, moderate, and severe AD cases (n = 18) were pretreated with fifteen different protocols and stained with each of the following antibodies: beta42, PHF-1, MC-1 and AT8. Random fields were digitally captured and images were thresholded to select for positively stained areas versus background (e.g. "load"). As previously reported, high concentrations of formic acid were extremely effective in enhancing the detection of beta-amyloid; as much as a 2-fold enhancement in Abeta "load" values were observed. Surprisingly, tau-related pathology detection also increased significantly following pretreatment. Depending on the antibody, between a 3-fold and 6-fold enhancement was possible relative to no pretreatment. Comparable results were found in paraffin-embedded sections. Similar enhancements in the detection of pathology were obtained following 99% formic acid exposure, microwaving in citrate buffer (pH 9.0) or exposure to 99% formic acid then boiling in citrate buffer (pH 6.0). Because the latter treatments were often harsh on the tissue and more difficult to control, we recommend a standard tissue pretreatment of 99% formic acid for seven minutes for both beta-amyloid and tau-related pathology.

The effect of nutritional intervention in elderly subjects residing in group-living for the demented

OBJECTIVES

We studied the nutritional status and the effects of nutritional intervention on body weight, cognition and activities of daily life (ADL)-function in demented individuals.

DESIGN

Controlled non-randomised study.

SETTING

Group-living for demented elderly (GLD), ie community assisted housing.

SUBJECTS AND INTERVENTIONS

Twenty-two residents living in one of two units (GLD-I), received oral liquid supplements (1720 kJ/410 kcal/day) and the personnel of the GLD-I were given nutritional education. Fourteen residents in the other unit (GLD-C) served as controls. After 6 months 21 (83 (4) y, 81% women) and 12 (85 (4) y, 100% women) of the participants, respectively, were re-examined according to body mass index (BMI, kg/m2), cognitive function (Mini Mental State Examination (MMSE, 0-30 p) and Clinical Dementia Rating Scale (CDR) and the Katz' ADL index.

RESULTS

Body mass index (BMI) < or =20 was found in 19% of the participants and 44% had BMI< or =23. BMI correlated with MMSE (r=0.43, P<0.01). The weight of the residents in the intervention group increased by 3.4 (3) kg (P=0.001) at follow-up, whereas the weight remained unchanged in the control group. The cognitive function was low at the start in both groups, ie MMSE approximately 9 and no apparent positive effect of the nutritional intervention was seen. In addition, the ADL functions appeared to deteriorate in both groups.

CONCLUSIONS

Being underweight was common among demented elderly in group-living and was related to low cognitive capacity. Five months of oral supplementation, along with education of personnel, was followed by a weight gain. In this study the nutritional treatment did not affect the rate of decline in cognitive function or Katz' ADL index.

SPONSORSHIP

Supported by grants from the Swedish National Board of Health and Social Welfare. Semper Foods AB provided the liquid supplements.

Extrapyramidal symptoms and signs in Alzheimer's disease: prevalence and correlation with the first symptom

OBJECTIVES

To determine the prevalence and clinical correlates of extrapyramidal signs (EPS) in outpatients with probable Alzheimer's disease (AD); to examine the appearance of EPS in association with the first symptom that led the patient or family to ask for medical help; to examine the association of the prevalence of EPS with gender, age at onset of the disease, duration of the disease, severity of dementia, functional disability, and potential use of neuroleptics; and to address the issue of the possible role of EPS as a predictive factor for the clinical course of the disease.

PATIENTS AND METHODS

We examined 126 patients meeting NINCDS-ADRDA* criteria for probable AD and 29 healthy, nondementia controls of comparable age and gender. Thirteen of the patients taking neuroleptics at the time of the examination were excluded from the main study group and formed a separate subgroup of AD/neuroleptics-positive. Twenty-eight of the AD/neuroleptics-free patients were re-examined during an 18-month period in order to determine the possible role of EPS as a predictive factor of the clinical course of the disease.

RESULTS

Only 8 percent of the AD/neuroleptics-free patients were free of EPS, while the corresponding percentage in the control group was 61.5 percent. The most common types of EPS presented in the patient group were hypomimia ([facial mask] 60 percent), difficulty in talking (53.66 percent), bradykinesia (51.4 percent), postural instability (47.33 percent), abnormal gait (34.66), and rigidity (26 percent), respectively. No significant differences were found when examining for the presence of resting tremor, other tremors, dystonias, and dyskinesias. With regard to the presence of EPS and the first symptom, no significant difference was found among patients whose first complaint was memory disorder (probable AD) and patients with other symptoms. When examining the association between the prevalence of EPS and gender or age at onset of the disease, no special correlation was detected. However, such a correlation was found between the prevalence of EPS and duration of the disease, as indicated by the fact that EPS appear in 78.9 percent of the patients with a duration of illness less than two years, but in 97 percent of the patients with a corresponding duration of two years or more. The mean duration of the disease in patients appearing with EPS is found to be 2.68 +/- 1.98 years. The presence of EPS increases proportionally with the progression of the disease and cognitive and functional decline. Patients with poor results in the MMSE (score of less than 11) appear to present EPS at a greater percentage than those with better performance on the examination (MMSE scores greater than 11). With regard to the association between EPS and functional ability in AD, it seems that the presence of EPS imposes difficulties in daily activities, as seen by the fact that patients with EPS have lower FRSSD scores (mean +/- SD: 14.87 +/- 10.53) than patients without EPS (5 +/- 2.58). After controlling for duration of the disease, the use of neuroleptics is found to influence the appearance of EPS in patients with AD. Almost all of the patients AD/neuroleptics-positive patients presented EPS (100 percent), while 92 percent of the AD/neuroleptics-free patients manifested such symptoms. Finally, we re-evaluated 28 patients, who were part of the initial AD/neuroleptics-free group, in order to determine whether the appearance of EPS could have prognostic value for the clinical course of the disease. Patients who presented EPS at initial examination appeared to deteriorate faster, mainly cognitively, but also functionally. The mean decrease in MMSE scores in patients with EPS was found to be 2.65 +/- 3.46; while in patients without EPS at initial visit, MMSE scores were 0.63 +/- 3.88. The functional decline seems to be less influenced by the presence of EPS. The corresponding mean decrease in FRSSD scores of the two groups was 2.1 +/- 5.55 and 1.8 +/- 2.1, respectively.

Assessment of suspected dementia

At the Second Canadian Consensus Conference on Dementia (CCCD) (February, 1998), a group of neurologists, geriatricians, and psychiatrists met to consider guidelines for evaluation of dementia in Canada. This review paper formed a background paper for their discussion of dementia diagnosis. These experts from across the country concluded that diagnosis of suspected dementia cases continued to rest on skilled clinical assessment. Mental status exam, preferably in some quantifiable form, has become an essential part of the assessment. Selected laboratory tests are advisable in all cases (CBC, TSH, electrolytes, calcium, and glucose), but the CCCD continued to advise that CT scanning was mandatory only in selected cases where clinical findings pointed to another possibility besides Alzheimer's disease. The growing list of other diagnostic measures with potential usefulness in diagnosis of Alzheimer's disease or dementia in general was reviewed, but the evidence was judged as insufficient to support routine use of these tests by physicians. As new treatments for Alzheimer's disease become available, neurologists face new diagnostic challenges--differentiating Mild Cognitive Impairment, Frontotemporal dementias and Mixed dementias, and Lewy Body Dementia. Guidelines to aid in differential diagnosis are presented.

The role of routine laboratory studies and neuroimaging in the diagnosis of dementia: a clinicopathological study

OBJECTIVE

To determine the neuropathological diagnoses of longitudinally followed patients with potentially reversible causes of dementia and to examine the results of the "dementia work-up," especially neuroimaging, by comparison with the pathological diagnosis.

DESIGN

A neuropathologic series of 61 consecutive patients, with review of clinical, laboratory, neuroimaging, and pathological results.

RESULTS

Of the 61 patients, forty-eight (79%) had a clinical diagnosis of probable or possible Alzheimer's disease (AD). Compared with the pathological diagnosis, the sensitivity and specificity of the clinical diagnosis of AD were 96% and 79%, respectively. Of the 61 patients, 9 had abnormal laboratory tests, the correction of which did not improve the subsequent course. These patients were found to have AD8 and frontotemporal dementia on pathology. In two patients, neuroimaging was helpful in the clinical diagnoses of frontotemporal dementia and progressive supranuclear palsy (PSP). Neuroimaging revealed cerebrovascular disease in 18 patients, only two of whom were suspected clinically. Pathology confirmed AD in 17 and PSP in 1 of these patients. Sensitivity and specificity for the clinical diagnosis of cerebrovascular disease in comparison with pathology were 6% and 98%, respectively. With the added information from neuroimaging, that sensitivity increased to 59% and specificity decreased to 81%.

CONCLUSIONS

All cases with abnormal laboratory or neuroimaging results had AD or some other neurodegenerative disease on pathology. The "dementia work-up" did not reveal any reversible causes for dementia in this group of patients. Neuroimaging may have a role, especially in the diagnosis of possible AD with concomitant cerebrovascular disease.

Anxiety, depression and psychosis in vascular dementia: prevalence and associations

BACKGROUND

Little is known about psychiatric symptoms in Vascular dementia (VaD).

METHOD

92 patients with VaD, and 92 patients with Alzheimer's disease (AD) are reported. The evaluation included standardised measures of mood and psychosis.

RESULTS

72% of VaD patients and 38% of those with AD had two or more anxiety symptoms. VaD patients with severe dementia (94%) were the most likely to be anxious. Depression was also significantly more common in VaD patients (19% vs. 8%) whereas psychotic symptoms were prevalent in both dementias.

CONCLUSION

Psychiatric symptoms are common in VaD, especially in patients with moderate or severe dementia. Rigorous assessment of psychiatric symptoms in VaD should be part of good clinical practice.

Tracking cognitive decline in Alzheimer's disease using the mini-mental state examination: a meta-analysis

OBJECTIVES

To estimate the annual rate of change scores (ARC) on the Mini-Mental State Examination (MMSE) in Alzheimer's disease (AD) and to identify study or population characteristics that may affect the ARC estimation.

METHODS

MEDLINE was searched for articles published from January 1981 to November 1997 using the following keywords: AD and longitudinal study or prognosis or cognitive decline. The bibliographies of review articles and relevant papers were searched for additional references. All retrieved articles were screened to meet the following inclusion criteria: (a) original study; (b) addressed cognitive decline or prognosis or course of AD; (c) published in English; (d) study population included AD patients with ascertainable sample size; (e) used either clinical or pathological diagnostic criteria; (f) longitudinal study design; and (g) used the MMSE as one of the outcome measures. Data were systematically abstracted from the included studies, and a random effects regression model was employed to synthesize relevant data across studies and to evaluate the effects of study methodology on ARC estimation and its effect size.

RESULTS

Of the 439 studies screened, 43 met all the inclusion criteria. After 6 studies with inadequate or overlapping data were excluded, 37 studies involving 3,492 AD patients followed over an average of 2 years were included in the meta-analysis. The pooled estimate of ARC was 3.3 (95% confidence interval [CI]: 2.9-3.7). The observed variability in ARC across studies could not be explained with the covariates we studied, whereas part of the variability in the effect size of ARC could be explained by the minimum MMSE score at entry and number of assessments.

CONCLUSIONS

A pooled average estimate of ARC in AD patients was 3.3 points (95% CI: 2.9-3.7) on the MMSE. Significant heterogeneity of ARC estimates existed across the studies and cannot be explained by the study or population characteristics investigated. Effect size of ARC was related to the initial MMSE score of the study population and the number of assessments.

Natural history of Alzheimer's disease and other dementias: review of the literature in the light of the findings from the Kungsholmen Project

The elderly population is increasing more than any other sector of the population. Dementia, a prevalent condition in the elderly, increases disability, morbidity and mortality among older people. For these reasons the possibility of predicting progression and prognosis has enormous importance. Despite the fact that dementia has gained widespread recognition in the past few decades, the knowledge of its natural history, in terms of progression and prognosis are not yet completely understood. However, thanks to longitudinal research, which has only recently begun to proliferate, not only is better comprehension of the continuity of the cognitive decline possible, but also the identification of some prognostic factors.

Assessment of progression and prognosis in 'possible' and 'probable' Alzheimer's disease

OBJECTIVE

The objective of this study was to assess the rate of progression and clinical predictors of decline in subjects with possible and probable Alzheimer's disease (AD).

DESIGN/SETTING

The annual rate of change (ARC) for cognitive/functional scales was calculated for 95 subjects with AD attending a memory clinic. Two consecutive ARCs were calculated for a subgroup of 39 subjects.

RESULTS

The ARCs were relatively normally distributed; however, there was a large degree of variability. Neither age nor duration of symptoms at presentations were predictive of the rate of decline. However, the data suggested an effect of gender, with males having a greater rate of decline in cognition (p = 0.02). Finally, the rate of progression over the first year did not predict the subsequent ARC (p = 0.25).

CONCLUSIONS

The high variability in ARCs observed in this study and poor correlation between consecutive ARCs suggest that neither mean ARC values nor the previous rate of decline can be used to aid clinicians in the assessment of response to acetylcholinesterase inhibitors or other specific treatments for AD.

Prognostic factors in very old demented adults: a seven-year follow-up from a population-based survey in Stockholm

OBJECTIVE

To detect prognostic factors in very old demented subjects with Alzheimer's disease (AD), vascular dementia (VaD), and other types of dementia (OD).

DESIGN

Follow-up clinical examinations of dementia patients from a population-based study after 3- and 7-year intervals.

SETTING AND PARTICIPANTS

In an established population aged 75 years and older in Stockholm, Sweden, there were 133 cases of AD, 52 of VaD, and 38 of OD.

MAIN OUTCOME MEASURES

Predictors of survival at 3- and 7-year follow-up examinations were evaluated by Cox proportional hazard models. Progression was measured as the annual rate of change in Mini-Mental State Examination (MMSE) scores. Linear models were used to evaluate predictors of progression.

RESULTS

Older age, male gender, low education, comorbidity, and functional disability predicted shorter 7-year survival in the 223 prevalent dementia cases. Other factors, including type of dementia, dementia severity, and duration of the disease were not significant. The average rate of cognitive decline in the 81 mild to moderate demented subjects who survived 3 years was 2.4 MMSE points per year. Type of dementia (AD vs OD), higher baseline cognitive function, and greater functional disability predicted faster decline. Despite similar survival probability, predictors of death varied as a function of dementia type: Older age (for AD and VaD), comorbidity (for AD and OD), and functional dependency (for VaD). In AD, prognostic factors were similar to those described for the combined dementia groups, with the exception of an accelerated cognitive decline among women.

CONCLUSIONS

Although methodological difficulties exist, it is possible to identify demented subjects with worse prognoses (shorter survival and faster cognitive decline) by using clinical and demographic data. Clinicians and healthcare planners should be aware of the potential usefulness of functional dependence as a prognostic indicator. Finally, the need for careful clinical examinations of demented subjects is stressed by the increased mortality found among those demented who are also affected by other chronic conditions.

Impact of anesthesia on the cognitive functioning of the elderly

Exposure to general anesthesia has been suggested as a possible cause of long-term cognitive impairment in elderly subjects. The present study reviews the literature in this field in order to describe postoperative cognitive impairment in elderly populations, to determine to what extent this may be attributed to anesthetic agents, and to consider evidence of a causal relationship between anesthesia and onset of senile dementia. A systematic literature search was conducted using five bibliographic databases (PASCAL, Medline, Excerpta Medica, Psychological Abstracts, and Science Citation Index). Significant cognitive dysfunction was found to be common in elderly persons 1 to 3 days after surgery, but reports of longer-term impairment are inconsistent due to the heterogeneity of the procedures used and populations targeted in such studies. Incidence rates vary widely according to type of surgery, suggesting that factors other than anesthesia explain a significant proportion of the observed variance. Anesthesia appears to be associated with longerterm cognitive disorder and the acceleration of senile dementia, but only in a small number of cases, suggesting the existence of other interacting etiological factors.

Eligibility of Alzheimer's disease clinic patients for clinical trials

OBJECTIVES

To identify the percentage of patients with Alzheimer's disease (AD) in a general clinic population who would be provisionally eligible for randomized clinical trials and the extent to which these patients represent the overall clinic-based population.

BACKGROUND

Many randomized clinical trials have restricted enrollment criteria that may limit generalizability, i.e., AD patients who fulfill selection criteria for phase III clinical trials may not be representative of other AD patients in clinical settings.

DESIGN AND SETTING

Patients diagnosed as probable or possible AD from the nine clinical sites of the State of California's Alzheimer's Disease Diagnostic and Treatment Centers (ADDTC) were selected on the basis of their provisionally fulfilling the inclusion and exclusion criteria of two typical AD clinical trials at the time of their first visit (ECG and brain imaging criteria were not available).

RESULTS

From a sample of 3470 subjects with possible or probable AD, overall, only 4.4% or 7.9% would have been provisionally eligible for each of two trials. Patients provisionally eligible were younger, relatively underrepresented by women, better educated, wealthier, and more likely to be white than ineligible patients. The major independent demographic predictors for eligibility were (1) income greater than $15,000 per year, (2) male gender, and (3) college education. More than 60% of probable AD patients were excluded because of significant behavioral problems; approximately one-quarter each were excluded because of significant medical or neurological problems. Allowing patients with probable or possible AD to enroll would have resulted in 10.6% being eligible.

CONCLUSION

Selection criteria for AD clinical trials result in a demographically and clinically constrained subgroup that is not representative of the overall clinic population.

The clinical epidemiology of Alzheimer's disease

Alzheimer's disease is a more common and malignant illness than was appreciated just 2 decades ago. In addition to being a major cause of mortality, it is costly and uniquely distressing for patients and their families. All indications are that the problem will grow as elderly populations expand. Fatalism regarding AD is premature, however. Much has been learned about this disease in only a few years, and it is hoped that this rate of discovery can be maintained or even accelerated in the future.

Psychotic symptoms in Parkinson's disease patients with dementia

OBJECTIVE

To assess the prevalence of psychotic symptoms in a group of patients with Parkinson's disease (PD) and dementia and examine the association of psychotic symptoms with neuropsychiatric problems, the level of distress reported by caregivers, and cognitive and functional impairment.

DESIGN

The psychotic and nonpsychotic patients with PD dementia were compared on a series of demographic, neuropsychiatric, behavioral, caregiver complaint, and cognitive measures.

SETTING

The database from nine university-based State of California Alzheimer's Disease Diagnostic and Treatment Centers (ADDTCs).

PARTICIPANTS

101 patients diagnosed with PD.

RESULTS

A total of 36 of the 101 patients (35.6%) had either hallucinations, delusions, or both. The psychotic patients had significantly more insomnia, confusion, agitation, personality changes, and self-care problems and were noted by their caregivers to be significantly more unmanageable at home than their nonpsychotic counterparts. On cognitive scales, psychotic patients were significantly more impaired.

CONCLUSION

Many patients with PD and dementia experience psychosis. Psychotic symptoms in PD dementia patients are associated with major behavioral, cognitive, and functional problems.

Dementia and depression: Co-distribution and risk factors in a geriatric in- and outpatient sample

The results of a cross-sectional study on N = 212 elderly in- and outpatients are presented including sociodemographic data, physical findings, CAT-scan and EEG, as well as psychological tests for cognitive performance and affective symptoms. Forty-one percent of the patients showed mild and 13% severe cognitive deficits. Depression was diagnosed in 23% of the severely impaired and in 16% of the cognitively mildly impaired or unimpaired patients. Statistical analysis revealed that increasing age, female sex and low premorbid intellectual level were significantly associated with loss of cognitive function. Dementia and depression were not significantly associated with each other. The only risk factor for depression was a history of affective illness, but not cognitive deficits or social situation. CAT-scan and EEG were abnormal in 50% of the patients; however, this did not correlate with cognitive impairment or the presence of depression. From this study it is concluded that depression and dementia coincide frequently in elderly patients, but that they are associated with different risk factors It is suggested that dementia and depression are treated as two distinct disease entities.

Natural history of Alzheimer's disease: prognostic value of plateaux

The aim of this 7-year inception cohort study was to determine the prognostic value of plateaux in cognitive decline in the course of Alzheimer's disease (AD) as well as their impact on the rate of progression of cognitive impairment. From a consecutive sample of 106 outpatients participating in a longitudinal study on AD, we selected 31 with a mild degree of mental deficit at presentation and a disease duration of at least 3 years when included into the study. All underwent extensive clinico-neuropsychological testing about every 6 months and there were no drop-outs. Mean period of follow-up lasted 6.8 (SD 2.9) years. Nineteen patients displayed a plateau, where a plateau refers to a patient's remaining on a mild level of cognitive decline for more than two years. Survival curves (Kaplan-Meier method) showed that patients with plateaux reached several end-points--very severe functional or cognitive impairment, urinary incontinence, death--significantly later than patients without (p < 0.04). Patients with plateaux showed a smaller cognitive loss (p < 0.01) in terms of the mean annual rate of progression of mental decline. In conclusion plateaux in an early stage of Alzheimer's Disease served to identify patients with a more favourable course.