Multicenter study of predictors of disease course in Alzheimer disease (the "predictors study"). II. Neurological, psychiatric, and demographic influences on baseline measures of disease severity

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.

Reduced Awareness of Memory Deficit is Associated With Increased Medicare Home Health Care Use in Dementia

OBJECTIVE

The objective of this study was to examine whether reduced awareness of memory deficits in individuals with dementia is associated with more frequent need for Medicare home health care services.

METHODS

Cross-sectional analyses were conducted in a multicenter, clinic-based cohort. In total, 192 participants diagnosed with dementia and their informants were independently asked whether or not the participant demonstrated cognitive symptoms of dementia related to memory and word-finding. Participant self-awareness was measured as the discrepancy between participant and caregiver report of these symptoms. Annual Medicare home health benefit use data was obtained from Medicare claims matched by year to the Predictors study visit.

RESULTS

Participants that used home health services had lower awareness scores than those who did not. Awareness remained independently associated with home health use in a logistic regression adjusted for age, gender, education, caregiver relationship, global cognition, dementia subtype, and medical comorbidities.

IMPLICATIONS

Reduced self-awareness of memory deficits in individuals with dementia is associated with more frequent use of Medicare home health services. The disproportionate use of in-home assistance as a function of awareness level may reflect dangers faced by patients, and challenges faced by caregivers, when patients have limited awareness of their memory deficits. Current results have implications for clinical care, caregiver education, and models of health care utilization.

Quantitative EEG Neurometric Analysis-Guided Neurofeedback Treatment in Dementia: 20 Cases. How Neurometric Analysis Is Important for the Treatment of Dementia and as a Biomarker?

Dementia is a debilitating degenerative disorder where the sufferer's cognitive abilities decline over time, depending on the type of dementia. The more common types of dementia include Alzheimer's disease and vascular or multi-infarct dementia. In this study, 20 subjects with dementia (9 of Alzheimer's type, and 11 with vascular dementia) were treated using qEEG-guided neurofeedback training. The Mini Mental Status Examination (MMSE) was used as the primary outcome measure. The results showed an increase of the MMSE scores for all subjects regardless of dementia type with an average MMSE score increase of 6 points, which was found to be significant. To our knowledge this is the first time the same modality was shown to be beneficial in both dementia groups.

Health-care use and cost in dementia caregivers: Longitudinal results from the Predictors Caregiver Study

OBJECTIVE

To examine the effects of caregiver and patient characteristics on caregivers' medical care use and cost.

METHODS

One hundred forty-seven caregiver/patient dyads were followed annually for 6 years in three academic Alzheimer's disease centers in the United States. Logistic, negative binomial, and generalized linear mixed models were used to examine overall effects of caregiver/patient characteristics on caregivers' hospitalizations, doctor visits, outpatient tests and procedures, and prescription and over-the-counter medications.

RESULTS

Patients' comorbid conditions and dependence were associated with increased health-care use and costs of caregivers. Increases in caregiver depressive symptoms are associated with increases in multiple domains of caregivers' health-care use and costs.

DISCUSSION

Findings suggest expanding our focus on dementia patients to include family caregivers to obtain a fuller picture of effects of caregiving. Primary care providers should integrate caregivers' needs in health-care planning and delivery. Clinical interventions that treat patients and caregivers as a whole will likely achieve the greatest beneficial effects.

Longitudinal medication usage in Alzheimer disease patients

This study examined in detail patterns of cholinesterase inhibitors (ChEIs) and memantine use and explored the relationship between patient characteristics and such use. Patients with probable Alzheimer disease AD (n=201) were recruited from the Predictors Study in 3 academic AD centers and followed from early disease stages for up to 6 years. Random effects logistic regressions were used to examine effects of patient characteristics on ChEIs/memantine use over time. Independent variables included measures of function, cognition, comorbidities, the presence of extrapyramidal signs, psychotic symptoms, age, sex, and patient's living situation at each interval. Control variables included assessment interval, year of study entry, and site. During a 6-year study period, rate of ChEIs use decreased (80.6% to 73.0%) whereas memantine use increased (2.0% to 45.9%). Random effects logistic regression analyses showed that ChEI use was associated with better function, no psychotic symptoms, and younger age. Memantine use was associated with better function, poorer cognition, living at home, later assessment interval, and later year of study entry. Results suggest that high rate of ChEI use and increasing memantine use over time are consistent with current practice guidelines of initiation of ChEIs in mild-to-moderate AD patients and initiation of memantine in moderate-to-severe patients.

Longitudinal relationships between Alzheimer disease progression and psychosis, depressed mood, and agitation/aggression

OBJECTIVES

Behavioral and psychological symptoms of dementia (BPSD) are prevalent in Alzheimer disease (AD) and are related to poor outcomes such as nursing home placement. No study has examined the impact of individual BPSD on dependence, a clinically important feature that reflects changing patient needs and their effect on caregivers. The current study characterized independent cross-sectional and longitudinal relationships between three BPSD (psychosis, depressed mood, and agitation/aggression), cognition, and dependence to better understand the interplay between these symptoms over time.

DESIGN

The Predictors Study measured changes in BPSD, cognition, and dependence every 6 months in patients with AD. Cross-sectional and longitudinal relationships between individual BPSD, cognition, and dependence over 6 years were characterized by using multivariate latent growth curve modeling. This approach characterizes independent changes in multiple outcome measures over time.

SETTING

Four memory clinics in the United States and Europe.

PARTICIPANTS

A total of 517 patients with probable AD.

MEASUREMENTS

Columbia University Scale for Psychopathology, modified Mini-Mental State Examination, and Dependence Scale.

RESULTS

Both psychosis and depressed mood at study entry were associated with worse subsequent cognitive decline. Independent of cognitive decline, initial psychosis was associated with worse subsequent increases in dependence. Rates of increase in agitation/aggression separately correlated with rates of declines in both cognition and independence.

CONCLUSIONS

Although purely observational, our findings support the poor prognosis associated with psychosis and depression in AD. Results also show that agitation/aggression tracks declines in cognition and independence independently over time. Targeted intervention for individual BPSD, particularly psychosis, could have broad effects not only on patient well-being but also on care costs and family burden.

Can Clinical Data Predict Progression to Dementia in Amnestic Mild Cognitive Impairment?

Background:

To determine whether clinical data obtained by history and physical examination can predict eventual progression to dementia in a cohort of elderly people with mild cognitive impairment.

Methods:

A prospective, longitudinal study of a cohort of elderly subjects with amnestic Mild Cognitive Impairment (MCI). Ninety subjects meeting the criteria for amnestic MCI were recruited and followed annually for an average of 3.3 years. Main outcome measure was the development of dementia determined by clinical assessment with confirmatory neuropsychological evaluation.

Results:

Fifty patients (56%) developed dementia on follow-up. They were older, had lower Mini-mental status exam (MMSE) scores and a shorter duration of symptoms at the time of first assessment. Multivariate logistic regression analysis identified age at symptom onset as the only clinical parameter which distinguished the group that deteriorated to dementia from the group that did not. The odds ratio for age was 1.1 (confidence interval 1.04 - 1.18).

Conclusions:

Patients presenting with amnestic MCI insufficient for the diagnosis of dementia are at high risk of developing dementia on follow-up. In our cohort, 56% were diagnosed with dementia over an average period of 5.9 years from symptom onset. The only clinical predictor for the eventual development of dementia was older age at symptom onset. Clinical features alone were insufficient to predict development of dementia.

Social cognition in Alzheimer's disease: a separate construct contributing to dependence

The extent to which social cognitive changes reflect a discrete constellation of symptoms dissociable from general cognitive changes in Alzheimer's disease (AD) is unclear. Moreover, whether social cognitive symptoms contribute to disease severity and progression is unknown. The current multicenter study investigated cross-sectional and longitudinal associations between social cognition measured with six items from the Blessed Dementia Rating Scale, general cognition, and dependence in 517 participants with probable AD. Participants were monitored every 6 months for 5.5 years. Results from multivariate latent growth curve models adjusted for sex, age, education, depression, and recruitment site revealed that social cognition and general cognition were unrelated cross-sectionally and throughout time. However, baseline levels of each were related independently to dependence, and change values of each were related independently to change in dependence. These findings highlight the separability of social and general cognition in AD. Results underscore the relevance of considering social cognition when modeling disease and estimating clinical outcomes related to patient disability.

Long-term associations between cholinesterase inhibitors and memantine use and health outcomes among patients with Alzheimer's disease

OBJECTIVES

To examine in an observational study (1) relationships between cholinesterase inhibitors (ChEI) and memantine use, and functional and cognitive end points and mortality in patients with Alzheimer's disease (AD); (2) relationships between other patient characteristics and these clinical end points; and (3) whether effects of the predictors change across time.

METHODS

The authors conducted a multicenter, natural history study that included three university-based AD centers in the United States. A total of 201 patients diagnosed with probable AD with modified Mini-Mental State Examination (MMSE) scores ≥ 30 at study entry were monitored annually for 6 years. Discrete-time hazard analyses were used to examine relationships between ChEI and memantine use during the previous 6 months reported at each assessment, and time to cognitive (MMSE score ≤ 10) and functional (Blessed Dementia Rating Scale score ≥ 10) end points and mortality. Analyses controlled for clinical characteristics, including baseline cognition, function, and comorbid conditions, and presence of extrapyramidal signs and psychiatric symptoms at each assessment interval. Demographic characteristics included baseline age, sex, education, and living arrangement at each assessment interval.

RESULTS

ChEI use was associated with delayed time in reaching the functional end point and death. Memantine use was associated with delayed time to death. Different patient characteristics were associated with different clinical end points.

CONCLUSIONS

Results suggest long-term beneficial effects of ChEI and memantine use on patient outcomes. As for all observational cohort studies, observed relationships should not be interpreted as causal effects.

Coupled cognitive and functional change in Alzheimer's disease and the influence of depressive symptoms

In Alzheimer's disease (AD), cognition and function are only moderately correlated in cross-sectional studies, and studies of their longitudinal association are less common. One potential non-cognitive contributor to function is depression, which has been associated with poorer clinical outcomes. The current study investigated longitudinal associations between functional abilities, cognitive status, and depressive symptoms in AD. 517 patients diagnosed with probable AD and enrolled in The Multicenter Study of Predictors of Disease Course in Alzheimer's Disease were included. Patients were followed at 6-month intervals over 5.5 years. Longitudinal changes in the Blessed Dementia Rating Scale, modified Mini-Mental State Exam, and the depression subscale of the Columbia University Scale for Psychopathology in AD were examined in a multivariate latent growth curve model that controlled for gender, age, education, and recruitment site. Results showed that cognition and function worsened over the study period, whereas depressive symptoms were largely stable. Rates of change in cognition and function were correlated across participants and coupled within participants, indicating that they travel together over time. Worse initial cognitive status was associated with faster subsequent functional decline, and vice versa. Higher level of depressive symptoms was associated with worse initial functioning and faster subsequent cognitive and functional decline. These findings highlight the importance of both cognitive and psychiatric assessment for functional prognosis. Targeting both cognitive and depressive symptoms in the clinical treatment of AD may have incremental benefit on functional abilities.

Utilization of antihypertensives, antidepressants, antipsychotics, and hormones in Alzheimer disease

This study explores the longitudinal relationship between patient characteristics and use of 4 drug classes (antihypertensives, antidepressants, antipsychotics, and hormones) that showed significant changes in use rates over time in patients with Alzheimer disease. Patient/caregiver-reported prescription medication usage was categorized by drug class for 201 patients from the Predictors Study. Patient characteristics included use of cholinesterase inhibitors and/or memantine, function, cognition, living situation, baseline age, and sex. Assessment interval, year of study entry, and site were controlled for. Before adjusting for covariates, useage increased for antihypertensives (47.8% to 62.2%), antipsychotics (3.5% to 27.0%), and antidepressants (32.3% to 40.5%); use of hormones decreased (19.4% to 5.4%). After controlling for patient characteristics, effects of time on the use of antidepressants were no longer significant. Antihypertensive use was associated with poorer functioning, concurrent use of memantine, and older age. Antipsychotic use was associated with poorer functioning and poorer cognition. Antidepressant use was associated with younger age, poorer functioning, and concurrent use of cholinesterase inhibitors and memantine. Hormone use was associated with being female and younger age. Findings suggest accurate modeling of the Alzheimer disease treatment paradigm for certain subgroups of patients should include antihypertensives and antipsychotics in addition to cholinesterase inhibitors and memantine.

Comparison of patient and caregiver reports of patient activity participation and its relationship to mental health in patients with Alzheimer's disease

The relationship between engagement in pleasant activities as rated by the patient and as rated by the caregiver from the patient's perspective was examined using structural equation modeling in a sample of patients (N = 277) diagnosed with mild to moderate Alzheimer's disease. The two activity participation ratings were only moderately related to one another. Furthermore, depression was the only significant predictor of the patient-rated activity participation, whereas severity of depression, degree of personality change, level of dependence, and cognition were all significant predictors of caregiver-rated activity participation. These findings suggest that caregivers consider a wider range of variables when evaluating the patient's engagement in activities than does the patient. Predictors of patient-rated activity participation did not differ as a function of age or cognition.

Evidence-based evaluation of diagnostic accuracy of resting EEG in dementia and mild cognitive impairment

Cognitive impairment is the most frequent chronic condition in the elderly, and dementia is the most disabling form of cognitive impairment in elderly. In the absence of specific and reliable markers of etiologically different dementia syndromes and their preclinical stages, diagnosis in living patients is probabilistic and based on standardized clinical diagnostic criteria. There is still not enough information on the validity of the EEG method in dementia work-up, and an updated evidence-based consensus on appropriateness of this method in the initial evaluation of patients with suspected cognitive disorder and dementia is missing. Using an evidence-based technique we searched for articles on diagnostic accuracy of spontaneous EEG in dementia disorders published from 1980 until June 2008. Inclusion criteria were: original article published in English with 10 or more subjects per diagnostic group, diagnosed according to the established consensus clinical diagnostic criteria used as a "gold standard." In addition, it should have been possible to calculate from the reported results indexes of diagnostic test accuracy: sensitivity, specificity, likelihood ratios and diagnostic odds ratios. Forty-six articles were retrieved that satisfied eligibility criteria. Thirty-four (74%) studies employed case-control design where study population was recruited from consecutive patients at specialist clinic settings, 12 (26%) were prospective in terms of reported clinical followup of study population. Four (9%) studies used population-based samples and 5 (11%) studies stated in methods the recruitment procedures for patients and healthy subjects. Number of patients included in diagnostic groups and healthy subjects varied in included studies between 10 and 180 and 10 and 171, respectively. Figures on sensitivity and specificity across the studies varied widely. Positive likelihood ratio in studies reporting classification accuracies between Alzheimer's disease and controls ranged between 2.3 and 38.5, and diagnostic odds ratios consequently showed large variations between 7 and 219. In conclusion, despite the wealth of published research and reported high indexes of diagnostic accuracy of EEG, and qEEG in particular, in individual studies, evidence of diagnostic utility of resting EEG in dementia and mild cognitive impairment (MCI) is still not sufficient to establish this method for the initial evaluation of subjects with cognitive impairment in the routine clinical practice. Joint effort of preferably multicenter studies using uniform standards should develop optimized methods, investigate added diagnostic value of EEG in clinically established dementia diagnosis and predictive utility of EEG in MCI and questionable dementia.

The relation of patient dependence to home health aide use in Alzheimer's disease

BACKGROUND

Although there has been much research devoted to understanding the predictors of nursing home placement (NHP) in Alzheimer's disease (AD) patients, there is currently a lack of research concerning the predictors of home health care. The objective of this study was to examine whether the Dependence Scale can predict home health aide (HHA) use.

METHODS

The sample is drawn from the Predictors Study, a large, multicenter cohort of patients with probable AD, prospectively followed annually for up to 7 years in three university-based AD centers in the United States. Markov analyses (n=75) were used to calculate annual transition probabilities for the "new onset" of HHA use (instances where an HHA was absent at the previous visit, but present at the next visit) as a function of HHA presence at the preceding year's visit and dependence level at that preceding year's visit.

RESULTS

The dependence level at the previous year's visit was a significant predictor of HHA use at the next year's visit. Three specific items of the Dependence Scale (needing household chores done for oneself, needing to be watched or kept company when awake, and needing to be escorted when outside) were significant predictors of the presence of an HHA.

CONCLUSION

The Dependence Scale is a valuable tool for predicting HHA use in AD patients. Obtaining a better understanding of home health care in AD patients may help delay NHP and have a positive impact on the health and well-being of both the caregiver and the patient.

Patient dependence and longitudinal changes in costs of care in Alzheimer's disease

BACKGROUND/AIMS

To examine the incremental effect of patients' dependence on others, on cost of medical and nonmedical care, and on informal caregiving hours over time.

METHODS

Data are obtained from 172 patients from the Predictors Study, a large, multicenter cohort of patients with probable Alzheimer disease (AD) followed annually for 4 years in 3 University-based AD centers in the USA. Enrollment required a modified Mini-Mental State Examination score >or=30. We examined the effects of patient dependence (measured by the Dependence Scale, DS) and function (measured by the Blessed Dementia Rating Scale, BDRS) on medical care cost, nonmedical care cost, and informal caregiving time using random effects regression models.

RESULTS

A one-point increase in DS score was associated with a 5.7% increase in medical cost, a 10.5% increase in nonmedical cost, and a 4.1% increase in caregiving time. A one-point increase in BDRS score was associated with a 7.6% increase in medical cost, a 3.9% increase in nonmedical cost and an 8.7% increase in caregiving time.

CONCLUSIONS

Both functional impairment and patient dependence were associated with higher costs of care and caregiving time. Measures of functional impairment and patient dependence provide unique and incremental information on the overall impact of AD on patients and their caregivers.

Measuring cerebral atrophy and white matter hyperintensity burden to predict the rate of cognitive decline in Alzheimer disease

OBJECTIVE

To determine if baseline measurements of cerebral atrophy and severity of white matter hyperintensity (WMH) predict the rate of future cognitive decline in patients with Alzheimer disease (AD).

DESIGN

Data were drawn from the Predictors Study, a longitudinal study that enrolls patients with mild AD and reassesses them every 6 months with use of the Columbia modified Mini-Mental State (mMMS) examination (score range, 0-57). Magnetic resonance images were analyzed to determine the severity of WMH, using the Scheltens scale, and the degree of atrophy, using the bicaudate ratio. Generalized estimating equations were used to determine whether severity of baseline magnetic resonance image measurements and their interaction predicted the rate of mMMS score decline at subsequent visits.

SETTING

Three university-based AD centers in the United States.

PARTICIPANTS

At baseline, 84 patients with AD from the Predictors Study received structural magnetic resonance imaging and were selected for analysis. They had a mean of 6 follow-up evaluations. Main Outcome Measure The mMMS score.

RESULTS

Generalized estimating equation models demonstrated that the degree of baseline atrophy (beta = -0.316; P = .04), the severity of WMH (beta = -0.173; P = .03), and their interaction (beta = -6.061; P = .02) predicted the rate of decline in mMMS scores.

CONCLUSIONS

Both degree of cerebral atrophy and severity of WMH are associated with the rapidity of cognitive decline in AD. Atrophy and WMH may have a synergistic effect on future decline in AD, such that patients with a high degree of both have a particularly precipitous cognitive course. These findings lend further support to the hypothesis that cerebrovascular pathological abnormalities contribute to the clinical syndrome of AD.

Distinct pools of beta-amyloid in Alzheimer disease-affected brain: a clinicopathologic study

OBJECTIVE

To determine whether beta-amyloid (Abeta) peptides segregated into distinct biochemical compartments would differentially correlate with clinical severity of Alzheimer disease (AD).

DESIGN

Clinicopathologic correlation study.

PARTICIPANTS

Twenty-seven patients from a longitudinal study of AD and 13 age- and sex-matched controls without a known history of cognitive impairment or dementia were included in this study.

INTERVENTIONS

Temporal and cingulate neocortex were processed using a 4-step extraction, yielding biochemical fractions that are hypothesized to be enriched with proteins from distinct anatomical compartments: TRIS (extracellular soluble), Triton (intracellular soluble), sodium dodecyl sulfate (SDS) (membrane associated), and formic acid (extracellular insoluble). Levels of Abeta(40) and Abeta(42) were quantified in each biochemical compartment by enzyme-linked immunosorbent assay.

RESULTS

The Abeta(42) level in all biochemical compartments was significantly elevated in patients with AD vs controls (P < .01). The Abeta(40) levels in the TRIS and formic acid fractions were elevated in patients with AD (temporal, P < .01; cingulate, P = .03); however, Triton and SDS Abeta(40) levels were similar in patients with AD and in controls. Functional impairment proximal to death correlated with Triton Abeta(42) (r = 0.48, P = .02) and SDS Abeta(42) (r = 0.41, P = .04) in the temporal cortex. Faster cognitive decline was associated with elevated temporal SDS Abeta(42) levels (P < .001), whereas slower decline was associated with elevated cingulate formic acid Abeta(42) and SDS Abeta(42) levels (P = .02 and P = .01, respectively).

CONCLUSION

Intracellular and membrane-associated Abeta, especially Abeta(42) in the temporal neocortex, may be more closely related to AD symptoms than other measured Abeta species.

The effects of patient function and dependence on costs of care in Alzheimer's disease

OBJECTIVES

To estimate incremental effects of patients' dependence and function on costs of care during the early stages of Alzheimer's disease (AD) and to compare strengths of their relationships with different cost components.

DESIGN

Multicenter, cross-sectional, observational study.

SETTING

Three university hospitals in the United States.

PARTICIPANTS

One hundred seventy-nine community-living patients with probable AD, with modified Mini-Mental State Examination scores of 30 or higher.

MEASUREMENTS

Patients' dependence was measured using the Dependence Scale (DS). Functional capacity was measured using the Blessed Dementia Rating Scale (BDRS). Total cost was measured by summing direct medical costs and informal costs. Direct medical costs included costs of hospitalization, outpatient treatment and procedures, assistive devices, and medications. Informal costs were estimated from time spent helping with basic and instrumental activities of daily living for up to three caregivers per patient using national average hourly earnings as wage rate.

RESULTS

DS and BDRS were associated with higher total cost; a 1-point increase in DS was associated with a $1,832 increase in total cost, and a 1-point increase in BDRS was associated with a $3,333 increase. Examining component costs separately identified potential differences between DS and BDRS. A 1-point increase in BDRS was associated with a $1,406 increase in direct medical cost. A 1-point increase in DS was associated with a $1,690 increase in informal cost.

CONCLUSION

Patients' dependence and function related differently to direct medical and informal cost, suggesting that measures of function and dependence provided unique information for explaining variations in cost of care for patients with AD, highlighting the value in measuring both constructs.

Home health and informal care utilization and costs over time in Alzheimer's disease

OBJECTIVES

To (1) compare home health and informal (unpaid) services utilization among patients with Alzheimer's disease (AD), (2) examine longitudinal changes in services use, and (3) estimate possible interdependence of home health and informal care utilization.

METHODS

The sample is drawn from the Predictors Study, a large, multicenter cohort of patients with probable AD, prospectively followed annually for up to 7 years in three university-based AD centers. Bivariate probit models estimated the effects of patient characteristics on home health and informal care utilization.

RESULTS

A large majority of the patients (80.6%) received informal care with a smaller proportion (18.6%) receiving home health services. Home health services utilization increased from 9.9% at baseline to 34.5% in year 4. Among users, number of days that services were provided in three-month recall increased from 21.9 to 56 days over time. Home health services utilization was significantly associated with function, depressive symptoms, being female, and not living with a spouse. Informal care utilization was significantly associated with cognition, function, comorbidities, and living with a spouse or child.

CONCLUSIONS

Home health and informal care utilization relate differently to patient characteristics. Utilization of home health care or informal care was not influenced by utilization of the other.

Comparison of costs of care between patients with Alzheimer's disease and dementia with Lewy bodies

BACKGROUND

The objective of this study was to compare total costs of care and its major components for community-living patients with Alzheimer's disease (AD) or dementia with Lewy bodies (DLB). This cross-sectional analysis of baseline data from the Predictors II Study took place in three university-based AD centers in the U.S.

METHODS

Community-living patients clinically diagnosed with probable AD (n = 170) or DLB (n = 25) with a modified Mini-Mental State examination (mMMS) score > or =30, equivalent to a score of approximately > or =16 on the Folstein Mini-Mental State Examination (MMSE), participated in this study. Patient and informant reported on patients' use of direct medical care, direct nonmedical care, and informal care. Patients' clinical and demographic characteristics included global cognitive status (measured by MMSE), functional capacity (measured by Blessed Dementia Rating Scale), psychotic symptoms, behavioral problems, depressive symptoms, extrapyramidal signs, comorbidities, age, and sex. Costs were compared by using covariate matching methods.

RESULTS

Unadjusted total costs and direct medical costs were not significantly different between AD and DLB patients. Compared with AD patients, unadjusted indirect costs were significantly higher and unadjusted direct nonmedical costs were significantly lower among DLB patients. After adjusting for age, sex, cognitive and functional status, differences in all cost components between DLB and AD patients were no longer statistically significant.

CONCLUSIONS

Apparent cost differences were largely attributed to differences in patients' cognitive and functional status. However, the small sample size for DLB patients might have limited power to detect statistically significant differences in costs of care between these groups.

The Cambridge Behavioral Inventory: validation and application in a memory clinic

The authors examined the validity of the Cambridge Behavioral Inventory (CBI), a questionnaire investigating broad neuropsychiatric symptoms and everyday functional ability in dementia. Test-retest reliability of the CBI was acceptable. Cross-validation with the Neuropsychiatric Inventory showed good concurrent validity of the CBI. The CBI reliably demonstrated that disinhibition, stereotypic behavior, elation, anxiety, poor self-care, and changes in eating habits occurred more commonly in patients with frontotemporal lobar degeneration than those with Alzheimer's disease. The authors concluded that the CBI is a reliable informant-based assessment of neuropsychiatric symptoms and everyday functioning and may be a suitable tool for use in general clinical practice settings.

Clinical characteristics and longitudinal changes of informal cost of Alzheimer's disease in the community

Most estimates of the cost of informal caregiving in patients with Alzheimer's disease (AD) remain cross-sectional. Longitudinal estimates of informal caregiving hours and costs are less frequent and are from assessments covering only short periods of time. The objectives of this study were to estimate long-term trajectories of the use and cost of informal caregiving for patients with AD and the effects of patient characteristics on the use and cost of informal caregiving. The sample is drawn from the Predictors Study, a large, multicenter cohort of patients with probable AD, prospectively followed annually for up to 7 years in three university-based AD centers in the United States (n=170). Generalized linear mixed models were used to estimate the effects of patient characteristics on use and cost of informal caregiving. Patients' clinical characteristics included cognitive status (Mini-Mental State Examination), functional capacity (Blessed Dementia Rating Scale (BDRS)), comorbidities, psychotic symptoms, behavioral problems, depressive symptoms, and extrapyramidal signs. Results show that rates of informal care use and caregiving hours (and costs) increased substantially over time but were related differently to patients' characteristics. Use of informal care was significantly associated with worse cognition, worse function, and higher comorbidities. Conditional on receiving informal care, informal caregiving hours (and costs) were mainly associated with worse function. Each additional point on the BDRS increased informal caregiving costs 5.4%. Average annual informal cost was estimated at $25,381 per patient, increasing from $20,589 at baseline to $43,030 in Year 4.

Depressive symptoms in Alzheimer's disease: natural course and temporal relation to function and cognitive status

OBJECTIVES

To examine the natural course of depressive symptoms in patients with probable Alzheimer's disease (AD), specifically, the temporal relationship between depressive symptoms, function, and cognitive status.

DESIGN

Multicenter cohort study with follow-up of up to 14 years.

SETTING

Patients from the two Multicenter Study of Predictors of Disease Course in Alzheimer's Disease (Predictors Study) cohorts were recruited at five sites in the United States and Europe.

PARTICIPANTS

Patients diagnosed with probable AD (n=536) enrolled in a longitudinal study (Predictors Study).

MEASUREMENTS

Depressive symptoms were evaluated at 6-month intervals using the Columbia Scale for Psychopathology in Alzheimer's Disease. The Modified Mini-Mental State (3MS) and Blessed Dementia Rating Scale (BDRS) were used to assess cognitive status and functional activity, respectively.

RESULTS

The prevalence of depressive symptoms was stable over the first 3 years of follow-up, at approximately 40%. There was a significant drop to 28% and 24% in the fourth and fifth years of follow-up, respectively. Time-dependent Cox analysis revealed that functional activity (BDRS) but not cognitive status (3MS) was a significant predictor of the first episode of depressive symptoms during follow-up. Generalized estimating equation analyses showed that AD duration and functional activity but not cognitive status were significantly related to depressive symptoms over the entire follow-up period.

CONCLUSION

Depressive symptoms are common in AD, but their prevalence decreases over time. Examination of the temporal relationship between depressive symptoms and risk factors suggests that decline in function but not in cognition precedes the first episode of depressive symptoms in patients with probable AD.

Psychopathological features in Alzheimer's disease: course and relationship with cognitive status

OBJECTIVES

To examine the course, clinical correlates, and relationship between cognitive status and psychopathological features in patients with probable Alzheimer's disease (AD) followed over a 5-year period.

DESIGN

Cohort study with follow-up of 5 years.

SETTING

Patients were recruited at three sites: 91 patients at Columbia Medical Center, 84 at Johns Hopkins School of Medicine, and 61 at Massachusetts General Hospital.

PARTICIPANTS

Patients diagnosed with probable AD (n = 236) enrolled in a longitudinal study (Predictors study).

MEASUREMENTS

Wandering/agitation, physical aggression, hallucinations, and delusions were evaluated at 6-month intervals using the Columbia Scale for Psychopathology in Alzheimer's Disease. Descriptive analyses were used to provide estimates of prevalence and course of psychopathological features. General estimating equations determined the odds of having any of the four psychopathological behaviors as a function of cognitive status. Markov analyses provided 6-month transition probabilities for psychopathological behaviors given patients' cognitive status and the presence or absence of such behaviors in the previous evaluation.

RESULTS

For wandering/agitation, prevalence (39-57%) and persistence increased as a function of time and decrement in cognitive status. Physical aggression was less prevalent (6-22%) and increased as a function of cognitive decline but tended to persist only in the more severely impaired patients. Delusions (34-49%) reached a peak at the second year and then declined. The odds of delusions were maximal with intermediate decline but remained persistent regardless of cognitive status. Hallucinations, despite some fluctuations, were relatively stable during the follow-up period (8-17%) and moderately persistent.

CONCLUSION

Psychopathological features, particularly wandering/agitation and delusions, in AD were common throughout the disease course. The natural history and persistence of the four psychopathological features varied. These findings provide important information to clinicians and caregivers regarding the course, predictability, and possible treatment of psychopathological behaviors in patients with probable AD.

Association between the APOE genotype and psychopathologic symptoms in Alzheimer's disease

BACKGROUND

Psychiatric symptoms occur frequently in the course of AD, are a frequent contributor to institutionalization, predict cognitive decline and death, and often require treatment with psychotropic medications. Previous studies investigating the association between APOE genotype and psychiatric symptomatology in AD have reported contradictory results.

OBJECTIVE

To determine whether APOE genotype predicts incident psychiatric symptomatology in patients with AD.

METHODS

Eighty-seven patients with AD at early stages and no psychiatric history were followed semiannually for up to 9.3 years (mean 5.5 years) for development of delusions, illusions, hallucinations, behavioral symptoms, and depression. Cox proportional hazards models were used to examine the relative risk for incident psychiatric symptomatology (outcome) in relation to APOE genotype (predictor).

RESULTS

The presence of one epsilon4 allele carried a 2.5-fold risk, whereas the presence of two epsilon4 alleles carried a 5.6-fold risk for development of delusions. The associations remained significant even when age, ethnicity, sex, education, duration of disease, and cognitive and functional performance were controlled for. The presence of two epsilon4 alleles was associated with reduced risk for developing hallucinations in the adjusted analysis only. No significant associations were detected between APOE genotype and the incidence of illusions, behavioral symptoms, or depression.

CONCLUSION

The presence of one or more epsilon4 alleles is a significant predictor for the incidence of delusions in the course of AD.

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.

Natural history of Alzheimer's disease

Alzheimer's disease (AD) is the principal cause of dementia in the elderly, and affects about 15 million people worldwide. The earliest symptom is usually an insidious impairment of memory. As the disease progresses, there is increasing impairment of language and other cognitive functions. Problems occur with naming and word-finding, and later with verbal and written comprehension and expression. Visuospatial, analytic and abstract reasoning abilities, judgment, and insight become affected. Behavioral changes may include delusions, hallucinations, irritability, agitation, verbal or physical aggression, wandering, and disinhibition. Ultimately, there is loss of self-hygiene, eating, dressing, and ambulatory abilities, and incontinence and motor dysfunction. Before diagnosis of AD, individuals may have memory complaints, which represent a period of mild cognitive impairment (MCI). Before MCI, there is a prodromal, ill-defined presymptomatic period of disease ('pre-MCI"). In this review, we particularly focus on these earliest stages. We also discuss the more advanced stages of AD, and address factors that may influence disease course. Understanding the natural history of AD will allow better targeting of the disease-modifying treatments that are on the horizon.

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.

Quality of life in patients with Alzheimer's disease as reported by patient proxies

OBJECTIVE

To measure behaviors indicative of quality of life (QOL) in patients with Alzheimer's disease and to examine correlates of patient QOL.

DESIGN

Cross-sectional investigation.

SETTING

Multi-center study.

PARTICIPANTS

Sample of 130 diagnosed patients. PRINCIPAL OUTCOME MEASURES: Proxy ratings of (1) the frequency, opportunity, and enjoyment of 15 non-ADL activities potentially within the capacity of a demented person, and (2) the frequency of a series of positive and negative affects, evident in clearly demarcated facial and bodily expressions.

RESULTS

QOL ratings were reliably elicited. Family and institutional caregivers differed only in reports of opportunity for patient activity. Frequency of activities declined with increasing severity of dementia. The frequency of negative affects increased and positive affects declined with increasing severity of dementia, but correlations were weak. High QOL, defined by frequent activity and positive affect, was evident in a quarter of the sample. In multivariate models, functional and cognitive status independently predicted QOL among community-resident older adults; only absence of antipsychotics was related to QOL among older people in nursing homes. Patient education, a marker of premorbid state, independently predicted some activity patterns.

CONCLUSIONS

Although the subjective world of the demented patient is not directly accessible, readily observable behaviors offer a basis for assessing QOL.

Risk of mortality and institutionalization in demented patients with delusions

Delusions are a common symptom during the course of dementia. Despite their clinical relevance, however, it is still unclear whether they are of prognostic value. This longitudinal study involving, at baseline, 99 demented Alzheimer disease (AD) and multi-infarct dementia (MID) patients, investigates the risk of mortality and institutionalization at 2 years after discharge from a dementia unit in patients with and without delusions at baseline. Results indicate that the presence of delusions is a significant predictor of future institutionalization (odds ratio 3.6, confidence interval 1.3-9.6), even when confounding factors such as age, educational level, and severity of cognitive and functional impairment are statistically controlled. No significant impact on survival was found.

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: diagnosis and evaluation

OBJECTIVE

To describe an approach to the diagnosis of dementia based on effective assessment methods.

DESIGN

We reviewed the literature and summarized the available diagnostic and prognostic studies of dementia that may be useful to the primary-care physician.

RESULTS

Although controversy exists about certain aspects of the diagnostic workup, exclusion of potentially reversible causes of dementia is essential. Laboratory studies (for example, for detection of underlying metabolic abnormalities) and neuroimaging of the brain may be useful. The pattern of onset and the temporal course of the disease may suggest a cause and help direct the investigation. Functional losses can substantially impair the patient's ability to live independently.

CONCLUSION

Dementia can be mistakenly considered as part of the normal aging process, and diagnosis necessitates a thorough, although not exhaustive, approach. Early identification of dementing illnesses improves the outcome for reversible disease and may also enhance the management of incurable dementias.

Progression and outcome of patients in a Canadian dementia clinic

Five hundred and fifty-three patients were referred to a Canadian dementia clinic for standardized evaluation. The majority (83.5%) had a dementia with Alzheimer's disease (AD) accounting for 89% of dementias. Patients with probable AD who were followed for five years had variable rates of progression, increased mortality (37.1%, 2.5 times the expected rate) and a high rate of institutionalization (79%). Simple demographic (age) and social factors (marital status) were strong predictors for institutionalization. It was extremely difficult at presentation to predict the rate of progression. The prevalence of AD in autopsied cases was 62.5%. Clinic patients were younger, had milder dementias, and were more likely to have AD than patients identified in the course of a contemporaneous population-based dementia prevalence study.